Dedicated to spreading the Good News of Basic and Applied Science at great research institutions world wide. Good science is a collaborative process. The rule here: Science Never Sleeps.
I am telling the reader this story in the hope of impelling him or her to find their own story and start a wordpress blog. We all have a story. Find yours.
The oldest post I can find for this blog is From FermiLab Today: Tevatron is Done at the End of 2011 (but I am not sure if that is the first post, just the oldest I could find.)
But the origin goes back to 1985, Timothy Ferris Creation of the Universe PBS, November 20, 1985, available in different videos on YouTube; The Atom Smashers, PBS Frontline November 25, 2008, centered at Fermilab, not available on YouTube; and The Big Bang Machine, with Sir Brian Cox of U Manchester and the ATLAS project at the LHC at CERN.
In 1993, our idiot Congress pulled the plug on The Superconducting Super Collider, a particle accelerator complex under construction in the vicinity of Waxahachie, Texas. Its planned ring circumference was 87.1 kilometers (54.1 mi) with an energy of 20 Tev per proton and was set to be the world’s largest and most energetic. It would have greatly surpassed the current record held by the Large Hadron Collider, which has ring circumference 27 km (17 mi) and energy of 13 TeV per proton.
If this project had been built, most probably the Higgs Boson would have been found there, not in Europe, to which the USA had ceded High Energy Physics.
(We have not really left High Energy Physics. Most of the magnets used in The LHC are built in three U.S. DOE labs: Lawrence Berkeley National Laboratory; Fermi National Accelerator Laboratory; and Brookhaven National Laboratory. Also, see below. the LHC based U.S. scientists at Fermilab and Brookhaven Lab.)
I have recently been told that the loss of support in Congress was caused by California pulling out followed by several other states because California wanted the collider built there.
The project’s director was Roy Schwitters, a physicist at the University of Texas at Austin. Dr. Louis Ianniello served as its first Project Director for 15 months. The project was cancelled in 1993 due to budget problems, cited as having no immediate economic value.
Some where I learned that fully 30% of the scientists working at CERN were U.S. citizens. The ATLAS project had 600 people at Brookhaven Lab. The CMS project had 1,000 people at Fermilab. There were many scientists which had “gigs” at both sites.
I started digging around in CERN web sites and found Quantum Diaries, a “blog” from before there were blogs, where different scientists could post articles. I commented on a few and my dismay about the lack of U.S recognition in the press.
Those guys at Quantum Diaries, gave me access to the Greybook, the list of every institution in the world in several tiers processing data for CERN. I collected all of their social media and was off to the races for CERN and other great basic and applied science.
Since then I have expanded the list of sites that I cover from all over the world. I build .html templates for each institution I cover and plop their articles, complete with all attributions and graphics into the template and post it to the blog. I am not a scientist and I am not qualified to write anything or answer scientific questions. The only thing I might add is graphics where the origin graphics are weak. I have a monster graphics library. Any science questions are referred back to the writer who is told to seek his answer from the real scientists in the project.
The blog has to date 900 followers on the blog, its Facebook Fan page and Twitter. I get my material from email lists and RSS feeds. I do not use Facebook or Twitter, which are both loaded with garbage in the physical sciences.
Authors: J. C. Mather, E. S. Cheng, D. A. Cottingham, R. E. Eplee Jr., D. J. Fixsen, T. Hewagama, R. B. Isaacman, K. A. Jensen, S. S. Meyer, P. D. Noerdlinger, S. M. Read, L. P. Rosen, R. A. Shafer, E. L. Wright, C. L. Bennett, N. W. Boggess, M. G. Hauser, T. Kelsall, S. H. Moseley Jr., R. F. Silverberg, G. F. Smoot, R. Weiss, and D. T. Wilkinson
First Author’s Institution: NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
Status: published in ApJ [open access]
Back in the mid-20th century, there were two competing theories about the origin of the Universe. Scientists, including Edwin Hubble and Georges Lemaître, had already established that space was expanding.
Some argued that if you run this expansion back in time, it implies a beginning when everything must have been compressed into a hot, dense singularity, exploding outward from that point in a “Big Bang”. Other astronomers, however, were uncomfortable with the idea that the Universe even had an origin at all. These scientists, most notably Fred Hoyle, argued instead for a cosmology in which the Universe had always existed and had always been expanding, with new galaxies springing up periodically to fill in the gaps. This picture of our Universe is referred to as the “Steady State Theory”.
These two theories predict fundamentally different things about the background temperature of the Universe. If matter in the Universe does not originate from a single point, as in the Steady State picture, then we would expect the background radiation to be chaotic in nature; there would be no reason for different unconnected regions of spacetime to look the same as each other.
However, if everything in the Universe comes from the same initial conditions, then everything should be roughly the same temperature. This can also be expressed as the idea that the Universe should be in thermodynamic equilibrium on large scales, and that if you measure the intensity of background radiation at all frequencies, you should see a blackbody spectrum—the characteristic spectrum of an object in equilibrium, dependent only on the object’s temperature. Thus, a key prediction of the Big Bang theory is that the temperature should be nearly constant over the entire sky, with the differences (called anisotropies) from this constant average temperature being extremely small—around one part in 100,000!
COBE comes to the rescue
Big Bang cosmologists in the 1960s believed that the peak of the Universe’s blackbody spectrum should be in the microwave frequency range, defined as between 300 MHz and 300 GHz. This would be expected from a massive explosion of energy at the Big Bang, the light from which would have been redshifted into the microwave range as it traveled through the expanding universe. So, if the Big Bang theory is true, we should expect to see a constant source of background radiation coming from all directions in the microwave sky: a so-called Cosmic Microwave Background, or CMB.
The detection of this CMB radiation in 1965 by Arno Penzias and Robert Woodrow Wilson, as well as the cosmological interpretation of that detection by Robert Dicke, Jim Peebles, Peter Roll, and David Wilkinson, laid the groundwork for modern cosmology, and was the beginning of the end for the idea that the Universe had no origin.
However, Penzias and Wilson’s discovery was not an accurate measurement of the CMB’s temperature or spectrum. No anisotropies had been detected, and there was still debate over whether or not the CMB spectrum was truly a blackbody. The goal of the Cosmic Background Explorer (COBE) satellite, launched by NASA in 1989, was to answer these lingering questions.
COBE was split into three instruments: the Differential Microwave Radiometer (DMR), the Far-InfraRed Absolute Spectrophotometer (FIRAS), and the Diffuse Infrared Background Experiment (DIRBE). DMR measured the CMB anisotropies, while DIRBE mapped infrared radiation from foreground dust.
igure 1: A diagram of the FIRAS instrument, taken from Figure 1a of Mather et. al. (1999).
FIRAS, meanwhile, was designed to measure the CMB spectrum. It scanned the entire sky multiple times in order to minimize errors, and measured the temperature over a wide range of frequencies between 30 and FIRAS, meanwhile, was designed to measure the CMB spectrum. It scanned the entire sky multiple times in order to minimize errors and measured the temperature over a wide range of frequencies between 30 and nearly 3000 GHz. After eliminating known sources of interference such as cosmic rays, as well as subtracting the effects of light from the Milky Way galaxy and of the Doppler shift caused by the movement of the Earth through space, these scans were then averaged together to create direct measurements of the CMB intensity at various frequencies.
Figure 2: The cosmic microwave background spectrum, as measured by FIRAS. It shows a near-perfect blackbody, with any deviations from total thermodynamic equilibrium being much too small to see. This plot is taken from Figure 4 of Fixsen et al. (1996), which notes that “uncertainties are a small fraction of the line thickness.”line thickness.”
The authors found that the background radiation in our universe is in fact extremely close to being a perfect bThe authors of today’s paper found that the background radiation in our Universe is in fact extremely close to being a perfect blackbody! The final temperature found by FIRAS was reported by Mather et al. (1999) to be 2.725 K, with an uncertainty of just 0.002 K! This is an incredibly high-precision measurement and represents the final nail in the coffin for cosmologies other than the Big Bang. John C. Mather received the Nobel Prize in 2006 for his work as FIRAS’s project lead.
Figure 3: A comparison of the abilities of the COBE [above], WMAP, and Planck satellites to resolve tiny fluctuations in the CMB temperature, called anisotropies. Image: NASA/JPL-Caltech/ESA (Wikimedia Commons)
Today, cosmologists use the CMB and its anisotropies to characterize the early history of the universe, find galaxy clusters in the later universe, and even look for new physics! The COBE measurements represented the dawn of a new era in cosmology, and laid the groundwork for modern CMB measurements. The science we do toToday, cosmologists use the CMB and its anisotropies to characterize the early history of the Universe, find galaxy clusters in the later Universe, and even look for new physics! Later full-sky measurements taken by the Wilkinson Microwave Anisotropy Probe (WMAP) and the Planck satellite added never-before-seen levels of precision to our ability to study the structure and content of the Universe, and future missions like LiteBIRD will continue to improve our ability to study the CMB even more closely, building on COBE’s groundbreaking data. These experiments still rely upon the CMB temperature established by FIRAS, which remains the definitive result even 23 years after its publication.
In physical cosmology, cosmic inflation, cosmological inflation is a theory of exponential expansion of space in the early universe. The inflationary epoch lasted from 10^−36 seconds after the conjectured Big Bang singularity to some time between 10^−33 and 10^−32 seconds after the singularity. Following the inflationary period, the universe continued to expand, but at a slower rate. The acceleration of this expansion due to dark energy began after the universe was already over 7.7 billion years old (5.4 billion years ago).
Inflation theory was developed in the late 1970s and early 80s, with notable contributions by several theoretical physicists, including Alexei Starobinsky at Landau Institute for Theoretical Physics, Alan Guth at Cornell University, and Andrei Linde at Lebedev Physical Institute. Alexei Starobinsky, Alan Guth, and Andrei Linde won the 2014 Kavli Prize “for pioneering the theory of cosmic inflation.” It was developed further in the early 1980s. It explains the origin of the large-scale structure of the cosmos. Quantum fluctuations in the microscopic inflationary region, magnified to cosmic size, become the seeds for the growth of structure in the Universe. Many physicists also believe that inflation explains why the universe appears to be the same in all directions (isotropic), why the cosmic microwave background radiation is distributed evenly, why the universe is flat, and why no magnetic monopoles have been observed.
The detailed particle physics mechanism responsible for inflation is unknown. The basic inflationary paradigm is accepted by most physicists, as a number of inflation model predictions have been confirmed by observation; however, a substantial minority of scientists dissent from this position. The hypothetical field thought to be responsible for inflation is called the inflaton.
In 2002 three of the original architects of the theory were recognized for their major contributions; physicists Alan Guth of M.I.T., Andrei Linde of Stanford, and Paul Steinhardt of Princeton shared the prestigious Dirac Prize “for development of the concept of inflation in cosmology”. In 2012 Guth and Linde were awarded the Breakthrough Prize in Fundamental Physics for their invention and development of inflationary cosmology.
Alan Guth, from M.I.T., who first proposed Cosmic Inflation.
“Some say the world will end in fire, some say in ice…” *
What will be the final destiny of the Universe? Probably it will end in ice, if we are to believe this year’s Nobel Laureates in Physics. They have studied several dozen exploding stars, called supernovae, and discovered that the Universe is expanding at an ever-accelerating rate. The discovery came as a complete surprise even to the Laureates themselves.
In 1998, cosmology was shaken at its foundations as two research teams presented their findings. Headed by Saul Perlmutter, one of the teams had set to work in 1988. Brian Schmidt headed another team, launched at the end of 1994, where Adam Riess was to play a crucial role.
The research teams raced to map the Universe by locating the most distant supernovae. More sophisticated telescopes on the ground and in space, as well as more powerful computers and new digital imaging sensors (CCD, Nobel Prize in Physics in 2009), opened the possibility in the 1990s to add more pieces to the cosmological puzzle.
The teams used a particular kind of supernova, called Type 1a supernova. It is an explosion of an old compact star that is as heavy as the Sun but as small as the Earth. A single such supernova can emit as much light as a whole galaxy. All in all, the two research teams found over 50 distant supernovae whose light was weaker than expected – this was a sign that the expansion of the Universe was accelerating. The potential pitfalls had been numerous, and the scientists found reassurance in the fact that both groups had reached the same astonishing conclusion.
For almost a century, the Universe has been known to be expanding as a consequence of the Big Bang about 14 billion years ago. However, the discovery that this expansion is accelerating is astounding. If the expansion will continue to speed up the Universe will end in ice.
The acceleration is thought to be driven by dark energy, but what that dark energy is remains an enigma – perhaps the greatest in physics today. What is known is that dark energy constitutes about three quarters of the Universe. Therefore the findings of the 2011 Nobel Laureates in Physics have helped to unveil a Universe that to a large extent is unknown to science. And everything is possible again.
*Robert Frost, Fire and Ice, 1920
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Astrobites is a daily astrophysical literature journal written by graduate students in astronomy. Our goal is to present one interesting paper per day in a brief format that is accessible to undergraduate students in the physical sciences who are interested in active research.
Why read Astrobites?
Reading a technical paper from an unfamiliar subfield is intimidating. It may not be obvious how the techniques used by the researchers really work or what role the new research plays in answering the bigger questions motivating that field, not to mention the obscure jargon! For most people, it takes years for scientific papers to become meaningful.
Our goal is to solve this problem, one paper at a time. In 5 minutes a day reading Astrobites, you should not only learn about one interesting piece of current work, but also get a peek at the broader picture of research in a new area of astronomy.
Great to hear from you. I just spoke on the phone at length with Gail. My Facebook page has been ruined by Facebook, presenting to me only “Suggested for you” and leaving no blank box in which to write. I do see your posts via email and am able to respond to them, but I cannot originate anything. This is a find a wide spread problem with solution or option to remove. zi learned that one can try on a different browser and I did and it worked for a while but then also presented only ” Suggested for you”. Facebook was my connection to you and the Silver Springs relatives since I do not travel. I am hoping this will end. Thanks a lot, Facebook.
Redevelopment plans could threaten the “Holmdel Horn”, the instrument that detected the “hiss” of background radiation from the Big Bang.
The “Holmdel Horn”, the microwave antenna that Arno Penzias and Robert Wilson used to detect the Cosmic Microwave Background [CMB] radiation that provided irrefutable evidence of the Big Bang, is under threat.
The antenna was designated a National Historic Landmark in 1989, and the American Physical Society lists it as a “historic physics site.” But new plans to build up the area could see the horn lost.
Arthur B. Crawford designed the Horn to support Project Echo, a NASA communications program. Echo satellites were inflated mylar spheres 100 feet (30 meters) across that orbited between 600 and 800 miles (1,000 and 1,300 km) above Earth. NASA made these simple passive microwave reflectors for intercontinental telephone, radio, and television transmission. Actively transmitting satellites rapidly made the Echo system obsolete, and the last Echo deorbited in 1968.
The Holmdel antenna itself is 50 feet long, with an opening 20 feet wide. The reflecting surface is parabolic, with incoming radiation coming to a focus at the small end of the horn, which houses a cryogenic receiver. The mount tracks in altitude and azimuth.
During their work with the antenna in the 1950s and 1960s, Penzias and Wilson encountered a persistent hissing noise. Modeling it as thermal emission, they initially estimated a blackbody temperature to be 4.2 kelvin. After meticulously checking the antenna and receiver, and even scrubbing the interior free of pigeon droppings, the noise persisted. They had no idea where it came from until MIT physicist Bernard F. Burke put Penzias and Wilson in touch with Princeton physicist Robert Dicke.
Dicke’s group had been working out whether evidence could be found to support the idea that the universe that began in a tiny, dense, hot state, and has been expanding ever since. In fact, they were about to build their own antenna. When the Princeton and Holmdel groups met, they realized that each had solved the other’s problems.
A pair of short papers appeared in The Astrophysical Journal Letters [below] in July 1965 announcing the findings, first Dicke’s theoretical treatment (with coauthors James Peebles, Peter Roll, and David Wilkinson) and then Penzias and Wilson’s observational findings, each paper acknowledging the other. The competing steady state theory, advanced by Hoyle, Gold, and Bondi in 1948, had no satisfactory explanation for the radiation, and faded into irrelevance.
Plaques at the site detail the history of the Holmdel Horn. Credit: Lawrence Faltz.
The antenna is located in Holmdel, New Jersey, just 27 miles as the crow flies from Times Square in Manhattan. The 43-acre site includes a 50,000 square-foot research building, now shuttered, at the base of Crawford Hill, which is the highest point in Monmouth County. At the top of the hill, the Horn is set in a field among a few other derelict structures built for communications research. The views across to Holmdel High School and out to Raritan Bay and Manhattan are dramatic.
The horn itself is intact, if a little weather worn. The property was originally owned by Bell Labs, the research arm of the Bell system until an anti-trust finding broke it up in 1983. Among its many inventions, Bell Labs created the transistor, CCDs, the solar cell, the UNIX operating system, and the C++ programming language. Nine Nobel prizes were awarded for Bell Labs inventions. In 2016, Nokia acquired what remained of Bell Labs after many transformations. The small building on the Crawford Hill site was shuttered, and the road to the top of the hill, where the antenna is located, was fenced off. It is now off-limits to visitors. In 2021, the site was sold to a developer, who is apparently interested in building high-end residences. Holmdel is one of New Jersey’s most affluent communities.
At a meeting on November 22nd, the Holmdel Township Committee passed a resolution asking the town’s Planning Board to determine if the Crawford Hill Horn Antenna site should be designated “an area in need of redevelopment.” If the town permits development of the site, most likely to build high-end residences, the Horn could be removed or even destroyed. The fact that it is a National Historic Landmark does not protect it. The horn is on private property and receives no Federal funds for its upkeep.
Three local organizations — Citizens for Informed Land Use, Friends of Holmdel Open Space, and Preserve Holmdel — have organized a petition and advocacy campaign that asks the town of Holmdel to not permit development but instead to create a park on Crawford Hill and preserve the Horn.
Sky & Telescope, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.
Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.
Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.
“Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”
With CMB-S4, scientists hope to connect a sandy desert with a polar desert—and revolutionize our understanding of the early universe.
In the 1960s, an anomalous, faint electromagnetic glow was observed across the entire sky. Physicists later determined that the light came from the very early universe, released when the first atoms formed shortly after the Big Bang.
“The fantastic thing about these [photons] is they have experienced the entire history of the universe,” says Julian Borrill, a senior scientist at the DOE’s Lawrence Berkeley National Laboratory. “And everything that has ever happened in the universe has left a tiny imprint on those photons; it’s changed their distribution and their energies slightly in all kinds of subtle ways.
“If we can measure them with enough precision and understand their statistics, we can tease out the entire history of the universe.”
Many experiments, both space- and ground-based, are already studying the CMB. Now scientists are developing plans for an ambitious project that would multiply by 10 the sensitivity of all these searches combined.
Called Cosmic Microwave Background-Stage 4, the project would comprise an array of small- and large-aperture telescopes deployed in Chile and at the South Pole. Building it would require unprecedented cooperation between two funding agencies and three scientific communities: astronomy, particle physics and polar science.
If scientists can pull it off, CMB-S4 will connect a sandy desert with a polar desert to address major astronomical questions.
“We’re going back to look for physics from the dawn of time and test the model for how our whole universe was created,” says John Carlstrom, a CMB-S4 project scientist and professor at the University of Chicago. “From that, we also learn a great deal about what’s in the universe, how it evolved from these quantum fluctuations to all the structure we see.
“We’re developing the full story of the universe from its infancy and creation to the present day.”
The science goals
For many of the over 400 scientists across 121 worldwide institutions who are part of the CMB-S4 collaboration, the most intriguing goal of the experiment is its search for evidence of cosmic inflation.
___________________________________________________________________ Cosmic Inflation Theory
In physical cosmology, cosmic inflation, cosmological inflation is a theory of exponential expansion of space in the early universe. The inflationary epoch lasted from 10^−36 seconds after the conjectured Big Bang singularity to some time between 10^−33 and 10^−32 seconds after the singularity. Following the inflationary period, the universe continued to expand, but at a slower rate. The acceleration of this expansion due to dark energy began after the universe was already over 7.7 billion years old (5.4 billion years ago).
Inflation theory was developed in the late 1970s and early 80s, with notable contributions by several theoretical physicists, including Alexei Starobinsky at Landau Institute for Theoretical Physics, Alan Guth at Cornell University, and Andrei Linde at Lebedev Physical Institute. Alexei Starobinsky, Alan Guth, and Andrei Linde won the 2014 Kavli Prize “for pioneering the theory of cosmic inflation.” It was developed further in the early 1980s. It explains the origin of the large-scale structure of the cosmos. Quantum fluctuations in the microscopic inflationary region, magnified to cosmic size, become the seeds for the growth of structure in the Universe. Many physicists also believe that inflation explains why the universe appears to be the same in all directions (isotropic), why the cosmic microwave background radiation is distributed evenly, why the universe is flat, and why no magnetic monopoles have been observed.
The detailed particle physics mechanism responsible for inflation is unknown. The basic inflationary paradigm is accepted by most physicists, as a number of inflation model predictions have been confirmed by observation;[a] however, a substantial minority of scientists dissent from this position. The hypothetical field thought to be responsible for inflation is called the inflaton.
In 2002 three of the original architects of the theory were recognized for their major contributions; physicists Alan Guth of M.I.T., Andrei Linde of Stanford, and Paul Steinhardt of Princeton shared the prestigious Dirac Prize “for development of the concept of inflation in cosmology”. In 2012 Guth and Linde were awarded the Breakthrough Prize in Fundamental Physics for their invention and development of inflationary cosmology.
Alan Guth, from M.I.T., who first proposed Cosmic Inflation.
Alan Guth’s notes: Alan Guth’s original notes on inflation.
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Cosmic inflation is a hypothetical event in which the universe rapidly expanded. “We think that inflation is one of the many hints for resolving the inconsistency between our two great theories of physics,” General Relativity and Quantum Mechanics, says Borrill, who serves as the CMB-S4 project data scientist.
Cosmic inflation would also explain, among other things, why areas of the universe that otherwise should not have ever been close enough together to affect one another still seem suspiciously similar.
The inflation process should have released gravitational waves, fluctuations in space-time that CMB-S4 is designed to detect.
Either detecting or ruling out the presence of primordial gravitational waves “would be a huge advance for our knowledge of the universe,” says Jeff McMahon, an associate professor at the University of Chicago and co-spokesperson for the CMB-S4 collaboration.
But an experiment of this scale and sensitivity would have the potential to do much more, including discover unknown subatomic particles from the early universe, explore the nature of dark matter and dark energy, map the matter in the cosmos, and capture transient phenomena in the microwave sky.
“I think the richness of the dataset means that it’s going to lead us in new directions, and those directions could be something new and exciting,” McMahon says. “I think there’s room for surprises.”
The telescopes
CMB-S4 is planning to place an array of microwave telescopes at two sites that have been vetted for their scientific value: the Atacama Plateau in Chile and the South Pole. The Simons Observatory, under construction in Chile, and the South Pole Observatory, operating in Antarctica, are among precursor “Stage-3” CMB experiments that could provide a solid basis for the development of CMB-S4.
To fulfill some of CMB-S4’s scientific goals, scientists will need to look at the same patch of sky for a long time, and the South Pole is conveniently oriented for this, as its view of the sky changes very little over the course of the year. Scientists plan to host at least 9 small-aperture telescopes 0.5 meters in diameter and one 5-meter large-aperture telescope at CMB-S4’s South Pole site to conduct an ultra-deep survey of 3% of the sky.
Other goals require scientists to collect data from a very large area of sky; the Chile site is well suited for this. At the CMB-S4 site in the Chilean Atacama Desert, scientists plan to use two 6-meter large-aperture telescopes to conduct a deep and wide survey of 70% of the sky.
The CMB-S4 collaboration plans to use hundreds of thousands of superconducting bolometers as their detectors. “The thing that makes these experiments sensitive is the number of detectors that they have in their focal plane,” says Kevin Huffenberger, a professor at Florida State University and co-spokesperson for the CMB-S4 collaboration. “[Even with] a better detector, you’re still looking through the same atmosphere, so it doesn’t really help… You have to build more detectors so that you can average down the atmosphere over more detectors.”
The design for CMB-S4, he says, offers “a big step up in the sensitivity, which allows it to do things that the other experiments couldn’t.”
Progress and planning
Three major studies have endorsed CMB-S4. It was recommended in 2014 by the Particle Physics Project Prioritization Panel, which outlines priorities for US particle physics; in 2015 by the National Academies report A Strategic Vision for NSF Investments in Antarctic and Southern Ocean Research, which defines the goals for the National Science Foundation Office of Polar Programs; and in November 2021 by the National Academies report Pathways to Discovery in Astronomy and Astrophysics, which outlines priorities for US astronomy and astrophysics in the coming decade.
The CMB-S4 team is planning for the project to be a partnership between the National Science Foundation and the US Department of Energy. In 2019, DOE formally established the scientific need for CMB-S4, and in 2020 it designated The DOE’s Lawrence Berkeley National Lab as the host laboratory. The funding agencies require additional reviews before approving the start of construction.
The seemingly slow progress is not unusual for an endeavor of this size, according to those involved. It’s a big project, and it takes a lot of time for the agencies to ensure that the project is well justified, says Huffenberger.
Marcelle Soares-Santos, an assistant professor at the University of Michigan and a convener of the group that focused on astrophysics at Snowmass2021, is also not surprised at the pace. “We all would like it to go faster, but I think it’s not unexpected to be at this stage,” she says. “There’s a reason why it requires support from the entire community—because it requires knowledge and expertise and resources that come from different corners of the community.”
The CMB-S4 team must also consider the allocation of the limited resources available at the NSF-managed South Pole Station, which due to its remoteness and the extreme cold, is only accessible for a few months a year. To optimally match the capabilities of CMB-S4 to the logistical constraints of deploying and operating the telescopes at the South Pole, the balance between the number of telescopes placed at each site is currently being reexamined through an “analysis of alternatives,” one of the many agency requirements before considering and approving the project for construction.
“We’re going over the different changes to the instrument configurations we could make that would still meet our instrument requirements [in order] to understand what fits best within the logistical footprint—for the South Pole Station especially, but also the project overall,” McMahon says.
That process should wrap up this year, he says, “then we should be ready to seek funding to move forward toward the next stages of design and then construction, with operations in the early 2030s.”
Unlike many other scientific disciplines, astrophysics can count on a certain generosity shown by nature. Our planet Earth is constantly graced by light arriving from celestial entities, from as close as the moon, the sun, the planets, and other objects in the solar system, outward to the stars throughout our galaxy, and farther and farther out to billions of galaxies, and even all the way back to the universe’s oldest light, the afterglow of the Big Bang.
Heavier bits of particles than light, known as cosmic rays, as well as the lightest particles of all, neutrinos, also make it all the way to us from across great cosmic divides.
We’ve even figured out how to wrangle the ultra-subtle (by the time they reach us) ripples in the fabric of spacetime, dubbed gravitational waves, that are heaved out by cataclysmic events like black hole collisions.
Quite simply, all we need do to catch these information-loaded incoming signals is to look and listen with our telescopes; build it, so to speak, and they will come. Earth’s atmosphere does block out various forms of light and particles, so to catch everything the universe is throwing our way, we often send space telescopes aloft. Yet as well as this wait-and-see approach works, it is not enough for the business of planetary science, a field intimately tied into broader astrophysics. To really understand what’s in our solar system—and extrapolate from there to all other space rocks and phenomena in all other solar systems—we have to go and get a closer look. Not enough light or other conveyer of information can reach us from the surfaces of solar system bodies to tell us what, say, the rocks on the moon or Mars are fully made of, or what Pluto actually looks like. We’ve accordingly sent astronauts to the moon and rovers to Mars, and sent a probe, called New Horizons, on a nine-year-voyage to finally see Pluto’s face.
This modus operandi continues now with the Lucy spacecraft, which will let us get up close and personal with the most numerous set of solar system objects yet to be visited, called the Trojan asteroids. NASA depiction of Lucy Mission to Jupiter’s Trojans
Alas, the laws of physics practically limit this active form of exploration, of going-and-getting, to just our solar system; even a probe somehow launched with the energetically unobtainable velocities in remote spitting distance of the speed of light would take decades, if not centuries to reach the nearest stars and exoplanets. We must therefore continue to hone our abilities to reap the harvest of the bounteous cosmic energy and matter that freely come to us right here on Earth.
On the trail of inflation with the BICEP experiment
Alan Guth, from M.I.T., who first proposed cosmic inflation
Lamda Cold Dark Matter Accerated Expansion of The universe http scinotions.com the-cosmic-inflation-suggests-the-existence-of-parallel-universes Alex Mittelmann, Coldcreation.
Alan Guth’s notes: Alan Guth’s original notes on inflation
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Researchers at The Kavli Institute for Particle Astrophysics and Cosmology KIPAC at Stanford University (US) have been on the hunt for a predicted signal left by inflation on the oldest light in the universe, known as the cosmic microwave background, or CMB [above]. Inflation supposes that the universe underwent a titanic expansion in size a mere trillionth of a trillionth of a trillionth into its existence during the Big Bang. This dramatic event should have generated ripples in spacetime, known as gravitational waves, that in turn would have left signatures in the CMB. A telescope located at the South Pole is running the so-called BICEP experiment [above], searching for these signatures. In the latest set of results from BICEP, the researchers announced they did not find the eagerly sought signatures. But, in the process, the researchers have constrained the properties these hypothetical waves would have. It’s a null result, but such results are integral for knowing when something, has in fact, been discovered. The hunt will go on.
Demolition derby in a nascent solar system
The later stages of planetary formation are theorized to be violent periods, marked by cataclysmic collisions between worlds as solar systems settle down into a stable configuration. Our own moon is thought to be the product of such a collision between a nascent Earth and a Mars-sized body lost to history. Now researchers at The MIT Kavli Institute for Astrophysics and Space Research (US) think they have spotted this same kind of planetary demolition derby happening in an alien solar system. That system, designated HD 172555, had been known to have large and varied dust signatures, originally attributed to a major planetary impact or an asteroid belt. The plot has recently thickened. In association with that dusty debris, MKI researchers and colleagues have newly reported the signature of a carbon monoxide gas ring. The presence of all that gas and dust suggest that two bodies collided, with one or both possessing considerable atmospheres. It’s a remarkable new finding and once more shows that what happened here historically in our solar system is likely not unusual; whether that extends to the formation of life, though, remains a big question.
From neutrinos to gravitational waves
Takaaki Kajita has had a full scientific life. A Principal Investigator at the Kavli Institute for the Physics and Mathematics of the Universe since 2007, Kajita won a Nobel Prize Physics in 2015 for his breakthrough work showing that neutrinos spontaneously change a property called flavor, revealing that the squirrely subatomic particles do in fact have mass. Yet as a recent article in Physics World relates, despite his success with neutrinos, Kajita wanted to enter into a new field, and did so in 2008. He began working on the experiment that has become Japan’s first gravitational-wave hunting instrument, known as KAGRA [above]. Kajita, who now serves as the KAGRA project’s principal investigator, is looking forward to the detector carrying on its observing campaign next year.
Neutron star mergers more of a goldmine than neutron star and black hole smashups.
MKI researchers have provided new insights on the origins of natural chemical elements heavier than iron. The nuclear fusion in stars produces most of the elements lighter than iron, including familiar elements like carbon and oxygen. But nuclear fusion factories cannot get hot and compacted enough to go past iron. Researchers have thus worked out that the extreme conditions created when ultra-dense stellar remnants called neutron stars collide must be what leads to the formation or gold, platinum, and other heavy elements, generally up through uranium. Similarly extreme conditions also occur when neutron stars and even more compact objects, black holes, cataclysmically meet. An analysis of these two kinds of mergers, presented in a recent study, bears out that at least over the last 2.5 billion years of cosmic history, neutron star mergers have been the dominant way the universe has forged heavy elements. The novel findings will help in constraining how, where, and when heavy elements—which are rarer than lighter elements—appeared in and became distributed throughout the cosmos, and with certain abundances cropping up here on Earth.
Lucy mission delving into the Solar System’s origins begins
In mid-October, NASA launched an exciting new mission, dubbed Lucy [above]. The Lucy spacecraft will make humanity’s first-ever visit to the Trojan asteroids—enigmatic space rocks clustered in two bunches in front of and behind the planet Jupiter in its orbit.
The Trojans are pristine time capsules from the early solar system, preserving chemical evidence of the conditions when our local worlds took shape over four eons ago. The project scientist for the Lucy mission is Richard Binzel, who is an affiliated faculty member of MKI. He points out that materials visible on the asteroids Lucy will visit could date back 4.56 billion years, right to the very dawn of our solar system and older than any samples we could study from the moon or find on Earth. The Trojans could shed light on the origin of carbon-containing compounds, so-called organics, necessary for the rise of life. The spacecraft will reach its first of several Trojan targets in 2027.
The Kavli Foundation based in Oxnard, California is dedicated to the goals of advancing science for the benefit of humanity and promoting increased public understanding and support for scientists and their work.
The Foundation’s mission is implemented through an international program of research institutes; professorships; and symposia in the fields of astrophysics; nanoscience; neuroscience; and theoretical physics as well as prizes in the fields of astrophysics; nanoscience; and neuroscience.
The Kavli Foundation was established in December 2000 by its founder and benefactor Fred Kavli a Norwegian business leader and philanthropist who made his money by creating Kavlico- a company that made sensors; and by investing in real estate in southern California and Nevada. David Auston, a former president of Case Western Reserve University(US) and former Bell Labs scientist, was the first president of the Kavli Foundation and is largely credited with the vision of the scientific investments. Kavli died in 2013 and his foundation is currently actively involved in establishing research institutes at universities throughout the United States, in Europe, and in Asia.
The Kavli Institute for Particle Astrophysics and Cosmology at Stanford University
The Kavli Institute for Cosmological Physics, University of Chicago
The Kavli Institute for Astrophysics and Space Research at the Massachusetts Institute of Technology
The Kavli Institute for Astronomy and Astrophysics at Peking University
The Kavli Institute for Cosmology at the University of Cambridge
The Kavli Institute for the Physics and Mathematics of the Universe at the University of Tokyo
Nanoscience
The Kavli Institute for Nanoscale Science at Cornell University
The Kavli Institute of Nanoscience at Delft University of Technology in the Netherlands
The Kavli Nanoscience Institute at the California Institute of Technology
The Kavli Institute for Bionano Science and Technology at Harvard University
The Kavli Energy NanoSciences Institute at University of California, Berkeley and the Lawrence Berkeley National Laboratory
Neuroscience
The Kavli Institute for Brain Science at Columbia University
The Kavli Institute for Brain & Mind at the University of California, San Diego
The Kavli Institute for Neuroscience at Yale University
The Kavli Institute for Systems Neuroscience at the Norwegian University of Science and Technology
The Kavli Neuroscience Discovery Institute at Johns Hopkins University
The Kavli Neural Systems Institute at The Rockefeller University
The Kavli Institute for Fundamental Neuroscience at the University of California, San Francisco
Theoretical physics
Kavli Institute for Theoretical Physics at the University of California, Santa Barbara
The Kavli Institute for Theoretical Physics China at the Chinese Academy of Sciences
Argonne-driven technology is part of a broad initiative to answer fundamental questions about the birth of matter in the universe and the building blocks that hold it all together.
Imagine the first of our species to lie beneath the glow of an evening sky. An enormous sense of awe, perhaps a little fear, fills them as they wonder at those seemingly infinite points of light and what they might mean. As humans, we evolved the capacity to ask big insightful questions about the world around us and worlds beyond us. We dare, even, to question our own origins.
“The place of humans in the universe is important to understand,” said physicist and computational scientist Salman Habib. “Once you realize that there are billions of galaxies we can detect, each with many billions of stars, you understand the insignificance of being human in some sense. But at the same time, you appreciate being human a lot more.”
The South Pole Telescope is part of a collaboration between Argonne and a number of national labs and universities to measure the CMB, considered the oldest light in the universe.
The high altitude and extremely dry conditions of the South Pole keep water vapor from absorbing select light wavelengths.
With no less a sense of wonder than most of us, Habib and colleagues at the U.S. Department of Energy’s (DOE) Argonne National Laboratory are actively researching these questions through an initiative that investigates the fundamental components of both particle physics and astrophysics.
The breadth of Argonne’s research in these areas is mind-boggling. It takes us back to the very edge of time itself, to some infinitesimally small portion of a second after the Big Bang when random fluctuations in temperature and density arose, eventually forming the breeding grounds of galaxies and planets.
It explores the heart of protons and neutrons to understand the most fundamental constructs of the visible universe, particles and energy once free in the early post-Big Bang universe, but later confined forever within a basic atomic structure as that universe began to cool.
And it addresses slightly newer, more controversial questions about the nature of Dark Matter and Dark Energy, both of which play a dominant role in the makeup and dynamics of the universe but are little understood.
_____________________________________________________________________________________ Dark Energy Survey
The Dark Energy Survey (DES) is an international, collaborative effort to map hundreds of millions of galaxies, detect thousands of supernovae, and find patterns of cosmic structure that will reveal the nature of the mysterious dark energy that is accelerating the expansion of our Universe. DES began searching the Southern skies on August 31, 2013.
According to Einstein’s theory of General Relativity, gravity should lead to a slowing of the cosmic expansion. Yet, in 1998, two teams of astronomers studying distant supernovae made the remarkable discovery that the expansion of the universe is speeding up. To explain cosmic acceleration, cosmologists are faced with two possibilities: either 70% of the universe exists in an exotic form, now called dark energy, that exhibits a gravitational force opposite to the attractive gravity of ordinary matter, or General Relativity must be replaced by a new theory of gravity on cosmic scales.
DES is designed to probe the origin of the accelerating universe and help uncover the nature of dark energy by measuring the 14-billion-year history of cosmic expansion with high precision. More than 400 scientists from over 25 institutions in the United States, Spain, the United Kingdom, Brazil, Germany, Switzerland, and Australia are working on the project. The collaboration built and is using an extremely sensitive 570-Megapixel digital camera, DECam, mounted on the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory, high in the Chilean Andes, to carry out the project.
Over six years (2013-2019), the DES collaboration used 758 nights of observation to carry out a deep, wide-area survey to record information from 300 million galaxies that are billions of light-years from Earth. The survey imaged 5000 square degrees of the southern sky in five optical filters to obtain detailed information about each galaxy. A fraction of the survey time is used to observe smaller patches of sky roughly once a week to discover and study thousands of supernovae and other astrophysical transients.
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“And this world-class research we’re doing could not happen without advances in technology,” said Argonne Associate Laboratory Director Kawtar Hafidi, who helped define and merge the different aspects of the initiative.
“We are developing and fabricating detectors that search for signatures from the early universe or enhance our understanding of the most fundamental of particles,” she added. “And because all of these detectors create big data that have to be analyzed, we are developing, among other things, artificial intelligence techniques to do that as well.”
Decoding messages from the universe
Fleshing out a theory of the universe on cosmic or subatomic scales requires a combination of observations, experiments, theories, simulations and analyses, which in turn requires access to the world’s most sophisticated telescopes, particle colliders, detectors and supercomputers.
Argonne is uniquely suited to this mission, equipped as it is with many of those tools, the ability to manufacture others and collaborative privileges with other federal laboratories and leading research institutions to access other capabilities and expertise.
As lead of the initiative’s cosmology component, Habib uses many of these tools in his quest to understand the origins of the universe and what makes it tick.
And what better way to do that than to observe it, he said.
“If you look at the universe as a laboratory, then obviously we should study it and try to figure out what it is telling us about foundational science,” noted Habib. “So, one part of what we are trying to do is build ever more sensitive probes to decipher what the universe is trying to tell us.”
To date, Argonne is involved in several significant sky surveys, which use an array of observational platforms, like telescopes and satellites, to map different corners of the universe and collect information that furthers or rejects a specific theory.
For example, the South Pole Telescope survey, a collaboration between Argonne and a number of national labs and universities, is measuring the cosmic microwave background (CMB) [above], considered the oldest light in the universe. Variations in CMB properties, such as temperature, signal the original fluctuations in density that ultimately led to all the visible structure in the universe.
Additionally, the Dark Energy Spectroscopic Instrument and the forthcoming Vera C. Rubin Observatory are specially outfitted, ground-based telescopes designed to shed light on dark energy and dark matter, as well as the formation of luminous structure in the universe.
All the data sets derived from these observations are connected to the second component of Argonne’s cosmology push, which revolves around theory and modeling. Cosmologists combine observations, measurements and the prevailing laws of physics to form theories that resolve some of the mysteries of the universe.
But the universe is complex, and it has an annoying tendency to throw a curve ball just when we thought we had a theory cinched. Discoveries within the past 100 years have revealed that the universe is both expanding and accelerating its expansion — realizations that came as separate but equal surprises.
Saul Perlmutter (center) [The Supernova Cosmology Project] shared the 2006 Shaw Prize in Astronomy, the 2011 Nobel Prize in Physics, and the 2015 Breakthrough Prize in Fundamental Physics with Brian P. Schmidt (right) and Adam Riess (left) [The High-z Supernova Search Team] for providing evidence that the expansion of the universe is accelerating.
“To say that we understand the universe would be incorrect. To say that we sort of understand it is fine,” exclaimed Habib. “We have a theory that describes what the universe is doing, but each time the universe surprises us, we have to add a new ingredient to that theory.”
Modeling helps scientists get a clearer picture of whether and how those new ingredients will fit a theory. They make predictions for observations that have not yet been made, telling observers what new measurements to take.
Habib’s group is applying this same sort of process to gain an ever-so-tentative grasp on the nature of dark energy and dark matter. While scientists can tell us that both exist, that they comprise about 68 and 26% of the universe, respectively, beyond that not much else is known.
Dark Matter Background Fritz Zwicky discovered Dark Matter in the 1930s when observing the movement of the Coma Cluster., Vera Rubin a Woman in STEM denied the Nobel, some 30 years later, did most of the work on Dark Matter.
Fritz Zwicky from http:// palomarskies.blogspot.com.
Coma cluster via NASA/ESA Hubble.
In modern times, it was astronomer Fritz Zwicky, in the 1930s, who made the first observations of what we now call dark matter. His 1933 observations of the Coma Cluster of galaxies seemed to indicated it has a mass 500 times more than that previously calculated by Edwin Hubble. Furthermore, this extra mass seemed to be completely invisible. Although Zwicky’s observations were initially met with much skepticism, they were later confirmed by other groups of astronomers.
Thirty years later, astronomer Vera Rubin provided a huge piece of evidence for the existence of dark matter. She discovered that the centers of galaxies rotate at the same speed as their extremities, whereas, of course, they should rotate faster. Think of a vinyl LP on a record deck: its center rotates faster than its edge. That’s what logic dictates we should see in galaxies too. But we do not. The only way to explain this is if the whole galaxy is only the center of some much larger structure, as if it is only the label on the LP so to speak, causing the galaxy to have a consistent rotation speed from center to edge.
Vera Rubin, following Zwicky, postulated that the missing structure in galaxies is dark matter. Her ideas were met with much resistance from the astronomical community, but her observations have been confirmed and are seen today as pivotal proof of the existence of dark matter.
Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science).
Vera Rubin measuring spectra, worked on Dark Matter (Emilio Segre Visual Archives AIP SPL).
Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970
Observations of cosmological structure — the distribution of galaxies and even of their shapes — provide clues about the nature of dark matter, which in turn feeds simple dark matter models and subsequent predictions. If observations, models and predictions aren’t in agreement, that tells scientists that there may be some missing ingredient in their description of dark matter.
But there are also experiments that are looking for direct evidence of dark matter particles, which require highly sensitive detectors [above]. Argonne has initiated development of specialized superconducting detector technology for the detection of low-mass dark matter particles.
This technology requires the ability to control properties of layered materials and adjust the temperature where the material transitions from finite to zero resistance, when it becomes a superconductor. And unlike other applications where scientists would like this temperature to be as high as possible — room temperature, for example — here, the transition needs to be very close to absolute zero.
Habib refers to these dark matter detectors as traps, like those used for hunting — which, in essence, is what cosmologists are doing. Because it’s possible that dark matter doesn’t come in just one species, they need different types of traps.
“It’s almost like you’re in a jungle in search of a certain animal, but you don’t quite know what it is — it could be a bird, a snake, a tiger — so you build different kinds of traps,” he said.
Lab researchers are working on technologies to capture these elusive species through new classes of dark matter searches. Collaborating with other institutions, they are now designing and building a first set of pilot projects aimed at looking for dark matter candidates with low mass.
Tuning in to the early universe
Amy Bender is working on a different kind of detector — well, a lot of detectors — which are at the heart of a survey of the cosmic microwave background (CMB).
“The CMB is radiation that has been around the universe for 13 billion years, and we’re directly measuring that,” said Bender, an assistant physicist at Argonne.
The Argonne-developed detectors — all 16,000 of them — capture photons, or light particles, from that primordial sky through the aforementioned South Pole Telescope, to help answer questions about the early universe, fundamental physics and the formation of cosmic structures.
Now, the CMB experimental effort is moving into a new phase, CMB-Stage 4 (CMB-S4).
This larger project tackles even more complex topics like Inflationary Theory, which suggests that the universe expanded faster than the speed of light for a fraction of a second, shortly after the Big Bang.
_____________________________________________________________________________________ Inflation
Alan Guth, from Highland Park High School and M.I.T., who first proposed cosmic inflation
[caption id="attachment_55311" align="alignnone" width="632"] HPHS Owls
Lamda Cold Dark Matter Accerated Expansion of The universe http scinotions.com the-cosmic-inflation-suggests-the-existence-of-parallel-universes Alex Mittelmann, Coldcreation
A section of a detector array with architecture suitable for future CMB experiments, such as the upcoming CMB-S4 project. Fabricated at Argonne’s Center for Nanoscale Materials, 16,000 of these detectors currently drive measurements collected from the South Pole Telescope. (Image by Argonne National Laboratory.)
While the science is amazing, the technology to get us there is just as fascinating.
Technically called transition edge sensing (TES) bolometers, the detectors on the telescope are made from superconducting materials fabricated at Argonne’s Center for Nanoscale Materials, a DOE Office of Science User Facility.
Each of the 16,000 detectors acts as a combination of very sensitive thermometer and camera. As incoming radiation is absorbed on the surface of each detector, measurements are made by supercooling them to a fraction of a degree above absolute zero. (That’s over three times as cold as Antarctica’s lowest recorded temperature.)
Changes in heat are measured and recorded as changes in electrical resistance and will help inform a map of the CMB’s intensity across the sky.
CMB-S4 will focus on newer technology that will allow researchers to distinguish very specific patterns in light, or polarized light. In this case, they are looking for what Bender calls the Holy Grail of polarization, a pattern called B-modes.
Capturing this signal from the early universe — one far fainter than the intensity signal — will help to either confirm or disprove a generic prediction of inflation.
It will also require the addition of 500,000 detectors distributed among 21 telescopes in two distinct regions of the world, the South Pole and the Chilean desert. There, the high altitude and extremely dry conditions keep water vapor in the atmosphere from absorbing millimeter wavelength light, like that of the CMB.
While previous experiments have touched on this polarization, the large number of new detectors will improve sensitivity to that polarization and grow our ability to capture it.
“Literally, we have built these cameras completely from the ground up,” said Bender. “Our innovation is in how to make these stacks of superconducting materials work together within this detector, where you have to couple many complex factors and then actually read out the results with the TES. And that is where Argonne has contributed, hugely.”
Down to the basics
Argonne’s capabilities in detector technology don’t just stop at the edge of time, nor do the initiative’s investigations just look at the big picture.
Most of the visible universe, including galaxies, stars, planets and people, are made up of protons and neutrons. Understanding the most fundamental components of those building blocks and how they interact to make atoms and molecules and just about everything else is the realm of physicists like Zein-Eddine Meziani.
“From the perspective of the future of my field, this initiative is extremely important,” said Meziani, who leads Argonne’s Medium Energy Physics group. “It has given us the ability to actually explore new concepts, develop better understanding of the science and a pathway to enter into bigger collaborations and take some leadership.”
Taking the lead of the initiative’s nuclear physics component, Meziani is steering Argonne toward a significant role in the development of the Electron-Ion Collider, a new U.S. Nuclear Physics Program facility slated for construction at DOE’s Brookhaven National Laboratory (US).
Argonne’s primary interest in the collider is to elucidate the role that quarks, anti-quarks and gluons play in giving mass and a quantum angular momentum, called spin, to protons and neutrons — nucleons — the particles that comprise the nucleus of an atom.
EIC Electron Animation, Inner Proton Motion.
Electrons colliding with ions will exchange virtual photons with the nuclear particles to help scientists “see” inside the nuclear particles; the collisions will produce precision 3D snapshots of the internal arrangement of quarks and gluons within ordinary nuclear matter; like a combination CT/MRI scanner for atoms. (Image by Brookhaven National Laboratory.)
While we once thought nucleons were the finite fundamental particles of an atom, the emergence of powerful particle colliders, like the Stanford Linear Accelerator Center at Stanford University and the former Tevatron at DOE’s Fermilab, proved otherwise.
It turns out that quarks and gluons were independent of nucleons in the extreme energy densities of the early universe; as the universe expanded and cooled, they transformed into ordinary matter.
“There was a time when quarks and gluons were free in a big soup, if you will, but we have never seen them free,” explained Meziani. “So, we are trying to understand how the universe captured all of this energy that was there and put it into confined systems, like these droplets we call protons and neutrons.”
Some of that energy is tied up in gluons, which, despite the fact that they have no mass, confer the majority of mass to a proton. So, Meziani is hoping that the Electron-Ion Collider will allow science to explore — among other properties — the origins of mass in the universe through a detailed exploration of gluons.
And just as Amy Bender is looking for the B-modes polarization in the CMB, Meziani and other researchers are hoping to use a very specific particle called a J/psi to provide a clearer picture of what’s going on inside a proton’s gluonic field.
But producing and detecting the J/psi particle within the collider — while ensuring that the proton target doesn’t break apart — is a tricky enterprise, which requires new technologies. Again, Argonne is positioning itself at the forefront of this endeavor.
“We are working on the conceptual designs of technologies that will be extremely important for the detection of these types of particles, as well as for testing concepts for other science that will be conducted at the Electron-Ion Collider,” said Meziani.
Argonne also is producing detector and related technologies in its quest for a phenomenon called neutrinoless double beta decay. A neutrino is one of the particles emitted during the process of neutron radioactive beta decay and serves as a small but mighty connection between particle physics and astrophysics.
“Neutrinoless double beta decay can only happen if the neutrino is its own anti-particle,” said Hafidi. “If the existence of these very rare decays is confirmed, it would have important consequences in understanding why there is more matter than antimatter in the universe.”
Argonne scientists from different areas of the lab are working on the Neutrino Experiment with Xenon Time Projection Chamber (NEXT) collaboration to design and prototype key systems for the collaborative’s next big experiment. This includes developing a one-of-a-kind test facility and an R&D program for new, specialized detector systems.
“We are really working on dramatic new ideas,” said Meziani. “We are investing in certain technologies to produce some proof of principle that they will be the ones to pursue later, that the technology breakthroughs that will take us to the highest sensitivity detection of this process will be driven by Argonne.”
The tools of detection
Ultimately, fundamental science is science derived from human curiosity. And while we may not always see the reason for pursuing it, more often than not, fundamental science produces results that benefit all of us. Sometimes it’s a gratifying answer to an age-old question, other times it’s a technological breakthrough intended for one science that proves useful in a host of other applications.
Through their various efforts, Argonne scientists are aiming for both outcomes. But it will take more than curiosity and brain power to solve the questions they are asking. It will take our skills at toolmaking, like the telescopes that peer deep into the heavens and the detectors that capture hints of the earliest light or the most elusive of particles.
We will need to employ the ultrafast computing power of new supercomputers. Argonne’s forthcoming Aurora exascale machine will analyze mountains of data for help in creating massive models that simulate the dynamics of the universe or subatomic world, which, in turn, might guide new experiments — or introduce new questions.
And we will apply artificial intelligence to recognize patterns in complex observations — on the subatomic and cosmic scales — far more quickly than the human eye can, or use it to optimize machinery and experiments for greater efficiency and faster results.
“I think we have been given the flexibility to explore new technologies that will allow us to answer the big questions,” said Bender. “What we’re developing is so cutting edge, you never know where it will show up in everyday life.”
Funding for research mentioned in this article was provided by Argonne Laboratory Directed Research and Development; Argonne program development; DOE Office of High Energy Physics: Cosmic Frontier, South Pole Telescope-3G project, Detector R&D; and DOE Office of Nuclear Physics.
DOE’s Argonne National Laboratory (US) seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their is a science and engineering research national laboratory operated by UChicago Argonne LLC for the United States Department of Energy. The facility is located in Lemont, Illinois, outside of Chicago, and is the largest national laboratory by size and scope in the Midwest.
Argonne had its beginnings in the Metallurgical Laboratory of the University of Chicago, formed in part to carry out Enrico Fermi’s work on nuclear reactors for the Manhattan Project during World War II. After the war, it was designated as the first national laboratory in the United States on July 1, 1946. In the post-war era the lab focused primarily on non-weapon related nuclear physics, designing and building the first power-producing nuclear reactors, helping design the reactors used by the United States’ nuclear navy, and a wide variety of similar projects. In 1994, the lab’s nuclear mission ended, and today it maintains a broad portfolio in basic science research, energy storage and renewable energy, environmental sustainability, supercomputing, and national security.
UChicago Argonne, LLC, the operator of the laboratory, “brings together the expertise of the University of Chicago (the sole member of the LLC) with Jacobs Engineering Group Inc.” Argonne is a part of the expanding Illinois Technology and Research Corridor. Argonne formerly ran a smaller facility called Argonne National Laboratory-West (or simply Argonne-West) in Idaho next to the Idaho National Engineering and Environmental Laboratory. In 2005, the two Idaho-based laboratories merged to become the DOE’s Idaho National Laboratory.
What would become Argonne began in 1942 as the Metallurgical Laboratory at the University of Chicago, which had become part of the Manhattan Project. The Met Lab built Chicago Pile-1, the world’s first nuclear reactor, under the stands of the University of Chicago sports stadium. Considered unsafe, in 1943, CP-1 was reconstructed as CP-2, in what is today known as Red Gate Woods but was then the Argonne Forest of the Cook County Forest Preserve District near Palos Hills. The lab was named after the surrounding forest, which in turn was named after the Forest of Argonne in France where U.S. troops fought in World War I. Fermi’s pile was originally going to be constructed in the Argonne forest, and construction plans were set in motion, but a labor dispute brought the project to a halt. Since speed was paramount, the project was moved to the squash court under Stagg Field, the football stadium on the campus of the University of Chicago. Fermi told them that he was sure of his calculations, which said that it would not lead to a runaway reaction, which would have contaminated the city.
Other activities were added to Argonne over the next five years. On July 1, 1946, the “Metallurgical Laboratory” was formally re-chartered as Argonne National Laboratory for “cooperative research in nucleonics.” At the request of the U.S. Atomic Energy Commission, it began developing nuclear reactors for the nation’s peaceful nuclear energy program. In the late 1940s and early 1950s, the laboratory moved to a larger location in unincorporated DuPage County, Illinois and established a remote location in Idaho, called “Argonne-West,” to conduct further nuclear research.
In quick succession, the laboratory designed and built Chicago Pile 3 (1944), the world’s first heavy-water moderated reactor, and the Experimental Breeder Reactor I (Chicago Pile 4), built-in Idaho, which lit a string of four light bulbs with the world’s first nuclear-generated electricity in 1951. A complete list of the reactors designed and, in most cases, built and operated by Argonne can be viewed in the, Reactors Designed by Argonne page. The knowledge gained from the Argonne experiments conducted with these reactors 1) formed the foundation for the designs of most of the commercial reactors currently used throughout the world for electric power generation and 2) inform the current evolving designs of liquid-metal reactors for future commercial power stations.
Conducting classified research, the laboratory was heavily secured; all employees and visitors needed badges to pass a checkpoint, many of the buildings were classified, and the laboratory itself was fenced and guarded. Such alluring secrecy drew visitors both authorized—including King Leopold III of Belgium and Queen Frederica of Greece—and unauthorized. Shortly past 1 a.m. on February 6, 1951, Argonne guards discovered reporter Paul Harvey near the 10-foot (3.0 m) perimeter fence, his coat tangled in the barbed wire. Searching his car, guards found a previously prepared four-page broadcast detailing the saga of his unauthorized entrance into a classified “hot zone”. He was brought before a federal grand jury on charges of conspiracy to obtain information on national security and transmit it to the public, but was not indicted.
Not all nuclear technology went into developing reactors, however. While designing a scanner for reactor fuel elements in 1957, Argonne physicist William Nelson Beck put his own arm inside the scanner and obtained one of the first ultrasound images of the human body. Remote manipulators designed to handle radioactive materials laid the groundwork for more complex machines used to clean up contaminated areas, sealed laboratories or caves. In 1964, the “Janus” reactor opened to study the effects of neutron radiation on biological life, providing research for guidelines on safe exposure levels for workers at power plants, laboratories and hospitals. Scientists at Argonne pioneered a technique to analyze the moon’s surface using alpha radiation, which launched aboard the Surveyor 5 in 1967 and later analyzed lunar samples from the Apollo 11 mission.
In addition to nuclear work, the laboratory maintained a strong presence in the basic research of physics and chemistry. In 1955, Argonne chemists co-discovered the elements einsteinium and fermium, elements 99 and 100 in the periodic table. In 1962, laboratory chemists produced the first compound of the inert noble gas xenon, opening up a new field of chemical bonding research. In 1963, they discovered the hydrated electron.
High-energy physics made a leap forward when Argonne was chosen as the site of the 12.5 GeV Zero Gradient Synchrotron, a proton accelerator that opened in 1963. A bubble chamber allowed scientists to track the motions of subatomic particles as they zipped through the chamber; in 1970, they observed the neutrino in a hydrogen bubble chamber for the first time.
Meanwhile, the laboratory was also helping to design the reactor for the world’s first nuclear-powered submarine, the U.S.S. Nautilus, which steamed for more than 513,550 nautical miles (951,090 km). The next nuclear reactor model was Experimental Boiling Water Reactor, the forerunner of many modern nuclear plants, and Experimental Breeder Reactor II (EBR-II), which was sodium-cooled, and included a fuel recycling facility. EBR-II was later modified to test other reactor designs, including a fast-neutron reactor and, in 1982, the Integral Fast Reactor concept—a revolutionary design that reprocessed its own fuel, reduced its atomic waste and withstood safety tests of the same failures that triggered the Chernobyl and Three Mile Island disasters. In 1994, however, the U.S. Congress terminated funding for the bulk of Argonne’s nuclear programs.
Argonne moved to specialize in other areas, while capitalizing on its experience in physics, chemical sciences and metallurgy. In 1987, the laboratory was the first to successfully demonstrate a pioneering technique called plasma wakefield acceleration, which accelerates particles in much shorter distances than conventional accelerators. It also cultivated a strong battery research program.
Following a major push by then-director Alan Schriesheim, the laboratory was chosen as the site of the Advanced Photon Source, a major X-ray facility which was completed in 1995 and produced the brightest X-rays in the world at the time of its construction.
On 19 March 2019, it was reported in the Chicago Tribune that the laboratory was constructing the world’s most powerful supercomputer. Costing $500 million it will have the processing power of 1 quintillion flops. Applications will include the analysis of stars and improvements in the power grid.
With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science. For more visit http://www.anl.gov.
The U. S. Department of Energy Office of Science’s Advanced Photon Source (APS) at Argonne National Laboratory is one of the world’s most productive X-ray light source facilities. The APS provides high-brightness X-ray beams to a diverse community of researchers in materials science, chemistry, condensed matter physics, the life and environmental sciences, and applied research. These X-rays are ideally suited for explorations of materials and biological structures; elemental distribution; chemical, magnetic, electronic states; and a wide range of technologically important engineering systems from batteries to fuel injector sprays, all of which are the foundations of our nation’s economic, technological, and physical well-being. Each year, more than 5,000 researchers use the APS to produce over 2,000 publications detailing impactful discoveries, and solve more vital biological protein structures than users of any other X-ray light source research facility. APS scientists and engineers innovate technology that is at the heart of advancing accelerator and light-source operations. This includes the insertion devices that produce extreme-brightness X-rays prized by researchers, lenses that focus the X-rays down to a few nanometers, instrumentation that maximizes the way the X-rays interact with samples being studied, and software that gathers and manages the massive quantity of data resulting from discovery research at the APS.
With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science. For more visit http://www.anl.gov.
About the Advanced Photon Source
The U. S. Department of Energy Office of Science’s Advanced Photon Source (APS) at Argonne National Laboratory is one of the world’s most productive X-ray light source facilities. The APS provides high-brightness X-ray beams to a diverse community of researchers in materials science, chemistry, condensed matter physics, the life and environmental sciences, and applied research. These X-rays are ideally suited for explorations of materials and biological structures; elemental distribution; chemical, magnetic, electronic states; and a wide range of technologically important engineering systems from batteries to fuel injector sprays, all of which are the foundations of our nation’s economic, technological, and physical well-being. Each year, more than 5,000 researchers use the APS to produce over 2,000 publications detailing impactful discoveries, and solve more vital biological protein structures than users of any other X-ray light source research facility. APS scientists and engineers innovate technology that is at the heart of advancing accelerator and light-source operations. This includes the insertion devices that produce extreme-brightness X-rays prized by researchers, lenses that focus the X-rays down to a few nanometers, instrumentation that maximizes the way the X-rays interact with samples being studied, and software that gathers and manages the massive quantity of data resulting from discovery research at the APS.
Studying the violent collisions of black holes and neutron stars may soon provide a new measurement of the Universe’s expansion rate, helping to resolve a long-standing dispute, suggests a new simulation study led by researchers at University College London (UK).
A black hole and star. Credit: iStock / Pitris.
Our two current best ways of estimating the Universe’s rate of expansion – measuring the brightness and speed of pulsating and exploding stars, and looking at fluctuations in radiation from the early Universe – give very different answers, suggesting our theory of the Universe may be wrong.
A third type of measurement, looking at the explosions of light and ripples in the fabric of space caused by black hole-neutron star collisions, should help to resolve this disagreement and clarify whether our theory of the Universe needs rewriting.
The new study, published in Physical Review Letters, simulated 25,000 scenarios of black holes and neutron stars colliding, aiming to see how many would likely be detected by instruments on Earth in the mid- to late-2020s.
The researchers found that, by 2030, instruments on Earth could sense ripples in space-time caused by up to 3,000 such collisions, and that for around 100 of these events, telescopes would also see accompanying explosions of light.
They concluded that this would be enough data to provide a new, completely independent measurement of the Universe’s rate of expansion, precise and reliable enough to confirm or deny the need for new physics.
Lead author Dr Stephen Feeney (UCL Physics & Astronomy) said: “A neutron star is a dead star, created when a very large star explodes and then collapses, and it is incredibly dense – typically 10 miles across but with a mass up to twice that of our Sun. Its collision with a black hole is a cataclysmic event, causing ripples of space-time, known as gravitational waves, that we can now detect on Earth with observatories like LIGO and Virgo.
Caltech/MIT Advanced aLigo at Hanford, WA(US), Livingston, LA(US) and VIRGO Gravitational Wave interferometer, near Pisa(IT).
“We have not yet detected light from these collisions. But advances in the sensitivity of equipment detecting gravitational waves, together with new detectors in India and Japan, will lead to a huge leap forward in terms of how many of these types of events we can detect. It is incredibly exciting and should open up a new era for astrophysics.”
To calculate the Universe’s rate of expansion, known as the Hubble constant, astrophysicists need to know the distance of astronomical objects from Earth as well as the speed at which they are moving away. Analysing gravitational waves tells us how far away a collision is, leaving only the speed to be determined.
To tell how fast the galaxy hosting a collision is moving away, we look at the “redshift” of light – that is, how the wavelength of light produced by a source has been stretched by its motion.
Explosions of light that may accompany these collisions would help us pinpoint the galaxy where the collision happened, allowing researchers to combine measurements of distance and measurements of redshift in that galaxy.
Dr Feeney said: “Computer models of these cataclysmic events are incomplete and this study should provide extra motivation to improve them. If our assumptions are correct, many of these collisions will not produce explosions that we can detect – the black hole will swallow the star without leaving a trace. But in some cases a smaller black hole may first rip apart a neutron star before swallowing it, potentially leaving matter outside the hole that emits electromagnetic radiation.”
Co-author Professor Hiranya Peiris (UCL Physics & Astronomy and Stockholm University [Stockholms universitet](SE)) said: “The disagreement over the Hubble constant is one of the biggest mysteries in cosmology. In addition to helping us unravel this puzzle, the spacetime ripples from these cataclysmic events open a new window on the universe. We can anticipate many exciting discoveries in the coming decade.”
Gravitational waves are detected at two observatories in the United States (the LIGO Labs), one in Italy (Virgo), and one in Japan (KAGRA). A fifth observatory, LIGO-India, is now under construction.
Our two best current estimates of the Universe’s expansion are 67 kilometres per second per megaparsec (3.26 million light years) and 74 kilometres per second per megaparsec. The first is derived from analysing the cosmic microwave background [CMB], the radiation left over from the Big Bang, while the second comes from comparing stars at different distances from Earth – specifically Cepheids, which have variable brightness, and exploding stars called type Ia supernovae.
Dr Feeney explained: “As the microwave background measurement needs a complete theory of the Universe to be made but the stellar method does not, the disagreement offers tantalising evidence of new physics beyond our current understanding. Before we can make such claims, however, we need confirmation of the disagreement from completely independent observations – we believe these can be provided through black hole-neutron star collisions.”
The study was carried out by researchers at UCL, Imperial College London (UK), Stockholm University and the University of Amsterdam [Universiteit van Amsterdam] (NL). It was supported by the Royal Society, the Swedish Research Council (VR), the Knut and Alice Wallenberg Foundation, and the Netherlands Organisation for Scientific Research (NWO).
Established in 1826, as London University by founders inspired by the radical ideas of Jeremy Bentham, UCL was the first university institution to be established in London, and the first in England to be entirely secular and to admit students regardless of their religion. University College London (UK) also makes contested claims to being the third-oldest university in England and the first to admit women. In 1836, University College London (UK) became one of the two founding colleges of the University of London, which was granted a royal charter in the same year. It has grown through mergers, including with the Institute of Ophthalmology (in 1995); the Institute of Neurology (in 1997); the Royal Free Hospital Medical School (in 1998); the Eastman Dental Institute (in 1999); the School of Slavonic and East European Studies (in 1999); the School of Pharmacy (in 2012) and the Institute of Education (in 2014).
University College London (UK) has its main campus in the Bloomsbury area of central London, with a number of institutes and teaching hospitals elsewhere in central London and satellite campuses in Queen Elizabeth Olympic Park in Stratford, east London and in Doha, Qatar. University College London (UK) is organised into 11 constituent faculties, within which there are over 100 departments, institutes and research centres. University College London (UK) operates several museums and collections in a wide range of fields, including the Petrie Museum of Egyptian Archaeology and the Grant Museum of Zoology and Comparative Anatomy, and administers the annual Orwell Prize in political writing. In 2019/20, UCL had around 43,840 students and 16,400 staff (including around 7,100 academic staff and 840 professors) and had a total income of £1.54 billion, of which £468 million was from research grants and contracts.
University College London (UK) is a member of numerous academic organisations, including the Russell Group(UK) and the League of European Research Universities, and is part of UCL Partners, the world’s largest academic health science centre, and is considered part of the “golden triangle” of elite, research-intensive universities in England.
University College London (UK) has many notable alumni, including the respective “Fathers of the Nation” of India; Kenya and Mauritius; the founders of Ghana; modern Japan; Nigeria; the inventor of the telephone; and one of the co-discoverers of the structure of DNA. UCL academics discovered five of the naturally occurring noble gases; discovered hormones; invented the vacuum tube; and made several foundational advances in modern statistics. As of 2020, 34 Nobel Prize winners and 3 Fields medalists have been affiliated with UCL as alumni, faculty or researchers.
History
University College London (UK) was founded on 11 February 1826 under the name London University, as an alternative to the Anglican universities of the University of Oxford(UK) and University of Cambridge(UK). London University’s first Warden was Leonard Horner, who was the first scientist to head a British university.
Despite the commonly held belief that the philosopher Jeremy Bentham was the founder of University College London (UK), his direct involvement was limited to the purchase of share No. 633, at a cost of £100 paid in nine installments between December 1826 and January 1830. In 1828 he did nominate a friend to sit on the council, and in 1827 attempted to have his disciple John Bowring appointed as the first professor of English or History, but on both occasions his candidates were unsuccessful. This suggests that while his ideas may have been influential, he himself was less so. However, Bentham is today commonly regarded as the “spiritual father” of University College London (UK), as his radical ideas on education and society were the inspiration to the institution’s founders, particularly the Scotsmen James Mill (1773–1836) and Henry Brougham (1778–1868).
In 1827, the Chair of Political Economy at London University was created, with John Ramsay McCulloch as the first incumbent, establishing one of the first departments of economics in England. In 1828 the university became the first in England to offer English as a subject and the teaching of Classics and medicine began. In 1830, London University founded the London University School, which would later become University College School. In 1833, the university appointed Alexander Maconochie, Secretary to the Royal Geographical Society, as the first professor of geography in the British Isles. In 1834, University College Hospital (originally North London Hospital) opened as a teaching hospital for the university’s medical school.
1836 to 1900 – University College, London
In 1836, London University was incorporated by royal charter under the name University College, London. On the same day, the University of London was created by royal charter as a degree-awarding examining board for students from affiliated schools and colleges, with University College and King’s College, London being named in the charter as the first two affiliates.[23]
The Slade School of Fine Art was founded as part of University College in 1871, following a bequest from Felix Slade.
In 1878, the University College London (UK) gained a supplemental charter making it the first British university to be allowed to award degrees to women. The same year University College London (UK) admitted women to the faculties of Arts and Law and of Science, although women remained barred from the faculties of Engineering and of Medicine (with the exception of courses on public health and hygiene). While University College London (UK) claims to have been the first university in England to admit women on equal terms to men, from 1878, the University of Bristol(UK) also makes this claim, having admitted women from its foundation (as a college) in 1876. Armstrong College, a predecessor institution of Newcastle University (UK), also allowed women to enter from its foundation in 1871, although none actually enrolled until 1881. Women were finally admitted to medical studies during the First World War in 1917, although limitations were placed on their numbers after the war ended.
In 1898, Sir William Ramsay discovered the elements krypton; neon; and xenon whilst professor of chemistry at University College London (UK).
1900 to 1976 – University of London, University College
In 1900, the University College London (UK) was reconstituted as a federal university with new statutes drawn up under the University of London Act 1898. UCL, along with a number of other colleges in London, became a school of the University of London. While most of the constituent institutions retained their autonomy, University College London (UK) was merged into the University in 1907 under the University College London (Transfer) Act 1905 and lost its legal independence. Its formal name became University College London (UK), University College, although for most informal and external purposes the name “University College, London” (or the initialism UCL) was still used.
1900 also saw the decision to appoint a salaried head of the college. The first incumbent was Carey Foster, who served as Principal (as the post was originally titled) from 1900 to 1904. He was succeeded by Gregory Foster (no relation), and in 1906 the title was changed to Provost to avoid confusion with the Principal of the University of London. Gregory Foster remained in post until 1929. In 1906, the Cruciform Building was opened as the new home for University College Hospital.
As it acknowledged and apologized for in 2021, University College London (UK) played “a fundamental role in the development, propagation and legitimisation of eugenics” during the first half of the 20th century. Among the prominent eugenicists who taught at University College London (UK) were Francis Galton, who coined the term “eugenics”, and Karl Pearson, and eugenics conferences were held at UCL until 2017.
sustained considerable bomb damage during the Second World War, including the complete destruction of the Great Hall and the Carey Foster Physics Laboratory. Fires gutted the library and destroyed much of the main building, including the dome. The departments were dispersed across the country to Aberystwyth; Bangor; Gwynedd; University of Cambridge (UK) ; University of Oxford (UK); Rothamsted near Harpenden; Hertfordshire; and Sheffield, with the administration at Stanstead Bury near Ware, Hertfordshire. The first UCL student magazine, Pi, was published for the first time on 21 February 1946. The Institute of Jewish Studies relocated to UCL in 1959.
The Mullard Space Science Laboratory(UK) was established in 1967. In 1973, UCL became the first international node to the precursor of the internet, the ARPANET.
Although University College London (UK) was among the first universities to admit women on the same terms as men, in 1878, the college’s senior common room, the Housman Room, remained men-only until 1969. After two unsuccessful attempts, a motion was passed that ended segregation by sex at University College London (UK). This was achieved by Brian Woledge (Fielden Professor of French at University College London (UK) from 1939 to 1971) and David Colquhoun, at that time a young lecturer in pharmacology.
1976 to 2005 – University College London (UK)
In 1976, a new charter restored University College London (UK) ‘s legal independence, although still without the power to award its own degrees. Under this charter the college became formally known as University College London (UK). This name abandoned the comma used in its earlier name of “University College, London”.
In 1986, University College London (UK) merged with the Institute of Archaeology. In 1988, University College London (UK) merged with the Institute of Laryngology & Otology; the Institute of Orthopaedics; the Institute of Urology & Nephrology; and Middlesex Hospital Medical School.
In 1993, a reorganisation of the University of London (UK) meant that University College London (UK) and other colleges gained direct access to government funding and the right to confer University of London degrees themselves. This led to University College London (UK) being regarded as a de facto university in its own right.
In 1994, the University College London (UK) Hospitals NHS Trust was established. University College London (UK) merged with the College of Speech Sciences and the Institute of Ophthalmology in 1995; the Institute of Child Health and the School of Podiatry in 1996; and the Institute of Neurology in 1997. In 1998, UCL merged with the Royal Free Hospital Medical School to create the Royal Free and University College Medical School (renamed the University College London (UK) Medical School in October 2008). In 1999, UCL merged with the School of Slavonic and East European Studies and the Eastman Dental Institute.
The University College London (UK) Jill Dando Institute of Crime Science, the first university department in the world devoted specifically to reducing crime, was founded in 2001.
Proposals for a merger between University College London (UK) and Imperial College London(UK) were announced in 2002. The proposal provoked strong opposition from University College London (UK) teaching staff and students and the AUT union, which criticised “the indecent haste and lack of consultation”, leading to its abandonment by University College London (UK) provost Sir Derek Roberts. The blogs that helped to stop the merger are preserved, though some of the links are now broken: see David Colquhoun’s blog and the Save University College London (UK) blog, which was run by David Conway, a postgraduate student in the department of Hebrew and Jewish studies.
The London Centre for Nanotechnology was established in 2003 as a joint venture between University College London (UK) and Imperial College London (UK). They were later joined by King’s College London(UK) in 2018.
Since 2003, when University College London (UK) professor David Latchman became master of the neighbouring Birkbeck, he has forged closer relations between these two University of London colleges, and personally maintains departments at both. Joint research centres include the UCL/Birkbeck Institute for Earth and Planetary Sciences; the University College London (UK) /Birkbeck/IoE Centre for Educational Neuroscience; the University College London (UK) /Birkbeck Institute of Structural and Molecular Biology; and the Birkbeck- University College London (UK) Centre for Neuroimaging.
2005 to 2010
In 2005, University College London (UK) was finally granted its own taught and research degree awarding powers and all University College London (UK) students registered from 2007/08 qualified with University College London (UK) degrees. Also in 2005, University College London (UK) adopted a new corporate branding under which the name University College London (UK) was replaced by the initialism UCL in all external communications. In the same year, a major new £422 million building was opened for University College Hospital on Euston Road, the University College London (UK) Ear Institute was established and a new building for the University College London (UK) School of Slavonic and East European Studies was opened.
In 2007, the University College London (UK) Cancer Institute was opened in the newly constructed Paul O’Gorman Building. In August 2008, University College London (UK) formed UCL Partners, an academic health science centre, with Great Ormond Street Hospital for Children NHS Trust; Moorfields Eye Hospital NHS Foundation Trust; Royal Free London NHS Foundation Trust; and University College London Hospitals NHS Foundation Trust. In 2008, University College London (UK) established the University College London (UK) School of Energy & Resources in Adelaide, Australia, the first campus of a British university in the country. The School was based in the historic Torrens Building in Victoria Square and its creation followed negotiations between University College London (UK) Vice Provost Michael Worton and South Australian Premier Mike Rann.
In 2009, the Yale UCL Collaborative was established between University College London (UK); UCL Partners; Yale University(US); Yale School of Medicine; and Yale – New Haven Hospital. It is the largest collaboration in the history of either university, and its scope has subsequently been extended to the humanities and social sciences.
2010 to 2015
In June 2011, the mining company BHP Billiton agreed to donate AU$10 million to University College London (UK) to fund the establishment of two energy institutes – the Energy Policy Institute; based in Adelaide, and the Institute for Sustainable Resources, based in London.
In November 2011, University College London (UK) announced plans for a £500 million investment in its main Bloomsbury campus over 10 years, as well as the establishment of a new 23-acre campus next to the Olympic Park in Stratford in the East End of London. It revised its plans of expansion in East London and in December 2014 announced to build a campus (UCL East) covering 11 acres and provide up to 125,000m^2 of space on Queen Elizabeth Olympic Park. UCL East will be part of plans to transform the Olympic Park into a cultural and innovation hub, where University College London (UK) will open its first school of design, a centre of experimental engineering and a museum of the future, along with a living space for students.
The School of Pharmacy, University of London merged with University College London (UK) on 1 January 2012, becoming the University College London (UK) School of Pharmacy within the Faculty of Life Sciences. In May 2012, University College London (UK), Imperial College London and the semiconductor company Intel announced the establishment of the Intel Collaborative Research Institute for Sustainable Connected Cities, a London-based institute for research into the future of cities.
In August 2012, University College London (UK) received criticism for advertising an unpaid research position; it subsequently withdrew the advert.
University College London (UK) and the Institute of Education formed a strategic alliance in October 2012, including co-operation in teaching, research and the development of the London schools system. In February 2014, the two institutions announced their intention to merge, and the merger was completed in December 2014.
In September 2013, a new Department of Science, Technology, Engineering and Public Policy (STEaPP) was established within the Faculty of Engineering, one of several initiatives within the university to increase and reflect upon the links between research and public sector decision-making.
In October 2013, it was announced that the Translation Studies Unit of Imperial College London would move to University College London (UK), becoming part of the University College London (UK) School of European Languages, Culture and Society. In December 2013, it was announced that University College London (UK) and the academic publishing company Elsevier would collaborate to establish the UCL Big Data Institute. In January 2015, it was announced that University College London (UK) had been selected by the UK government as one of the five founding members of the Alan Turing Institute(UK) (together with the universities of Cambridge, University of Edinburgh(SCL), Oxford and University of Warwick(UK)), an institute to be established at the British Library to promote the development and use of advanced mathematics, computer science, algorithms and big data.
2015 to 2020
In August 2015, the Department of Management Science and Innovation was renamed as the School of Management and plans were announced to greatly expand University College London (UK) ‘s activities in the area of business-related teaching and research. The school moved from the Bloomsbury campus to One Canada Square in Canary Wharf in 2016.
University College London (UK) established the Institute of Advanced Studies (IAS) in 2015 to promote interdisciplinary research in humanities and social sciences. The prestigious annual Orwell Prize for political writing moved to the IAS in 2016.
In June 2016 it was reported in Times Higher Education that as a result of administrative errors hundreds of students who studied at the UCL Eastman Dental Institute between 2005–06 and 2013–14 had been given the wrong marks, leading to an unknown number of students being attributed with the wrong qualifications and, in some cases, being failed when they should have passed their degrees. A report by University College London (UK) ‘s Academic Committee Review Panel noted that, according to the institute’s own review findings, senior members of University College London (UK) staff had been aware of issues affecting students’ results but had not taken action to address them. The Review Panel concluded that there had been an apparent lack of ownership of these matters amongst the institute’s senior staff.
In December 2016 it was announced that University College London (UK) would be the hub institution for a new £250 million national dementia research institute, to be funded with £150 million from the Medical Research Council and £50 million each from Alzheimer’s Research UK and the Alzheimer’s Society.
In May 2017 it was reported that staff morale was at “an all time low”, with 68% of members of the academic board who responded to a survey disagreeing with the statement ” University College London (UK) is well managed” and 86% with “the teaching facilities are adequate for the number of students”. Michael Arthur, the Provost and President, linked the results to the “major change programme” at University College London (UK). He admitted that facilities were under pressure following growth over the past decade, but said that the issues were being addressed through the development of UCL East and rental of other additional space.
In October 2017 University College London (UK) ‘s council voted to apply for university status while remaining part of the University of London. University College London (UK) ‘s application to become a university was subject to Parliament passing a bill to amend the statutes of the University of London, which received royal assent on 20 December 2018.
The University College London (UK) Adelaide satellite campus closed in December 2017, with academic staff and student transferring to the University of South Australia(AU). As of 2019 UniSA and University College London (UK) are offering a joint masters qualification in Science in Data Science (international).
In 2018, University College London (UK) opened UCL at Here East, at the Queen Elizabeth Olympic Park, offering courses jointly between the Bartlett Faculty of the Built Environment and the Faculty of Engineering Sciences. The campus offers a variety of undergraduate and postgraduate master’s degrees, with the first undergraduate students, on a new Engineering and Architectural Design MEng, starting in September 2018. It was announced in August 2018 that a £215 million contract for construction of the largest building in the UCL East development, Marshgate 1, had been awarded to Mace, with building to begin in 2019 and be completed by 2022.
In 2017 University College London (UK) disciplined an IT administrator who was also the University and College Union (UCU) branch secretary for refusing to take down an unmoderated staff mailing list. An employment tribunal subsequently ruled that he was engaged in union activities and thus this disciplinary action was unlawful. As of June 2019 University College London (UK) is appealing this ruling and the UCU congress has declared this to be a “dispute of national significance”.
2020 to present
In 2021 University College London (UK) formed a strategic partnership with Facebook AI Research (FAIR), including the creation of a new PhD programme.
Research
University College London (UK) has made cross-disciplinary research a priority and orientates its research around four “Grand Challenges”, Global Health, Sustainable Cities, Intercultural Interaction and Human Wellbeing.
In 2014/15, University College London (UK) had a total research income of £427.5 million, the third-highest of any British university (after the University of Oxford and Imperial College London). Key sources of research income in that year were BIS research councils (£148.3 million); UK-based charities (£106.5 million); UK central government; local/health authorities and hospitals (£61.5 million); EU government bodies (£45.5 million); and UK industry, commerce and public corporations (£16.2 million). In 2015/16, University College London (UK) was awarded a total of £85.8 million in grants by UK research councils, the second-largest amount of any British university (after the University of Oxford), having achieved a 28% success rate. For the period to June 2015, University College London (UK) was the fifth-largest recipient of Horizon 2020 EU research funding and the largest recipient of any university, with €49.93 million of grants received. University College London (UK) also had the fifth-largest number of projects funded of any organisation, with 94.
According to a ranking of universities produced by SCImago Research Group University College London (UK) is ranked 12th in the world (and 1st in Europe) in terms of total research output. According to data released in July 2008 by ISI Web of Knowledge, University College London (UK) is the 13th most-cited university in the world (and most-cited in Europe). The analysis covered citations from 1 January 1998 to 30 April 2008, during which 46,166 UCL research papers attracted 803,566 citations. The report covered citations in 21 subject areas and the results revealed some of University College London (UK) ‘s key strengths, including: Clinical Medicine (1st outside North America); Immunology (2nd in Europe); Neuroscience & Behaviour (1st outside North America and 2nd in the world); Pharmacology & Toxicology (1st outside North America and 4th in the world); Psychiatry & Psychology (2nd outside North America); and Social Sciences, General (1st outside North America).
University College London (UK) submitted a total of 2,566 staff across 36 units of assessment to the 2014 Research Excellence Framework (REF) assessment, in each case the highest number of any UK university (compared with 1,793 UCL staff submitted to the 2008 Research Assessment Exercise (RAE 2008)). In the REF results 43% of University College London (UK) ‘s submitted research was classified as 4* (world-leading); 39% as 3* (internationally excellent); 15% as 2* (recognised internationally) and 2% as 1* (recognised nationally), giving an overall GPA of 3.22 (RAE 2008: 4* – 27%, 3* – 39%, 2* – 27% and 1* – 6%). In rankings produced by Times Higher Education based upon the REF results, University College London (UK) was ranked 1st overall for “research power” and joint 8th for GPA (compared to 4th and 7th respectively in equivalent rankings for the RAE 2008).
richardmitnick
3:18 pm on February 18, 2021 Permalink
| Reply Tags: "New metamaterials for studying the oldest light in the universe", ACTPol and Advanced ACTPol telescopes, Antireflection coatings work by reflecting light from each side of the coating in such a way that the reflected particles of light interfere and cancel each other eliminating reflection., Atacama Cosmology Telescope called ACT, CMB - Cosmic Microwave Background, CMB-S4 21 telescopes at the South Pole and the Chilean Atacama desert surveying the sky with 550000 cryogenically-cooled superconducting detectors for 7 years will deliver transformative discoveries. ( 2 ), Cosmology Large Angular Scale Surveyor (CLASS) is an array of microwave telescopes at a high-altitude site in the Atacama Desert of Chile as part of the Parque Astronómico de Atacama., DOE’s Fermi National Accelerator Laboratory(US) ( 16 ), LBL The Simons Array in the Atacama in Chileal altitude 5200 m (17100 ft), Metamaterials are engineered materials with properties that aren’t naturally occurring., Primordial Inflation Polarization Explorer (PIPER) millimeter-wave telescope on a high-altitude scientific balloon, The single-crystal silicon lenses are transparent to microwaves and ultrapure so that the light passing through the lens won’t be absorbed or scattered by impurities., These antireflective lenses are the state of the art — and the Fermilab team are the only people in the world who make them., TolTEC Camera on UMass Amherst and Mexico’s Instituto Nacional de Astrofísica Óptica y Electrónica Large Millimeter Telescope on top of the Sierra Negra.
The cosmic microwave background, or CMB, is the electromagnetic echo of the Big Bang, radiation that has been traveling through space and time since the very first atoms were born 380,000 years after our universe began.
CMB per ESA/Planck.
Mapping minuscule variations in the CMB tells scientists about how our universe came to be and what it’s made of.
To capture the ancient, cold light from the CMB, researchers use specialized telescopes equipped with ultrasensitive cameras for detecting millimeter-wavelength signals. The next-generation cameras will contain up to 100,000 superconducting detectors. Fermilab scientist and University of Chicago(US) Associate Professor Jeff McMahon and his team have developed a new type of metamaterials-based antireflection coating for the silicon lenses used in these cameras.
“There are at least half a dozen projects that would not be possible without these,” McMahon said.
Metamaterials are engineered materials with properties that aren’t naturally occurring. The magic is in the microstructure — tiny, repeating features smaller than the wavelength of the light they are designed to interact with. These features bend, block or otherwise manipulate light in unconventional ways.
Left: One of the lenses developed by McMahon’s team is installed in a camera assembly. Top right: This shows a close-up view of the stepped pyramid metamaterial structure responsible for the lens’ antireflective properties. Bottom right: Members of the McMahon lab stand by recently fabricated silicon lenses. Credit: Jeff McMahon.
Generally, antireflection coatings work by reflecting light from each side of the coating in such a way that the reflected particles of light interfere and cancel each other, eliminating reflection. For McMahon’s metamaterials, the “coating” is a million tiny, precise cuts in each side of each silicon lens. Up close, the features look like stepped pyramids — three layers of square pillars stacked on top of each other. The pillars’ spacing and thickness is fine-tuned to create the maximum destructive interference between reflected light.
“Light just goes sailing right through with a tenth of a percent chance of reflecting,” McMahon said.
The single-crystal silicon lenses are transparent to microwaves and ultrapure so that the light passing through the lens won’t be absorbed or scattered by impurities. Silicon has the necessary light-bending properties for getting light from the telescope onto a large array of sensors, and the metamaterial structure takes care of reflection. Because each lens is made from a single pure silicon crystal, they can withstand cryogenic temperatures (the detectors have to operate at 0.1 kelvins) without the risk of cracking or peeling like lenses with antireflective coatings made from a different material.
All told, these lenses are arguably the best technology available for CMB instruments, McMahon says.
“It’s not exactly that you couldn’t do the experiment otherwise,” McMahon said, but for the performance and durability demanded by current and next-generation CMB surveys, these lenses are the state of the art — and his team are the only people in the world who make them.
McMahon and his team began developing the technology about 10 years ago when they started working on a new type of detector array and realized that they needed a better, less reflective lens to go with it. The hard part, he says, was figuring out how to make it. Techniques existed for making micrometer-accurate cuts in flat silicon wafers, but nobody had ever applied them to a lens before. The first lens they made, for the Atacama Cosmology Telescope, called ACT, took 12 weeks to fabricate because of the huge number of cuts that needed to be made.
Princeton Atacama Cosmology Telescope, on Cerro Toco in the Atacama Desert in the north of Chile, near the Llano de Chajnantor Observatory, Altitude 4,800 m (15,700 ft).
Now with improved machines and automation at Fermilab, the process takes just four days per lens, and McMahon hopes they will be able to streamline it even further.
Jeff McMahon and his team have developed new techniques for working with curved lenses instead of flat silicon wafers for CMB telescope lenses. Credit: Jeff McMahon.
Working at the University of Michigan until January 2020, McMahon’s team fabricated about 20 lenses for current CMB experiments including ACTPol and Advanced ACTPol (above), CLASS, TolTEC and PIPER.
Cosmology Large Angular Scale Surveyor (CLASS) is an array of microwave telescopes at a high-altitude site in the Atacama Desert of Chile as part of the Parque Astronómico de Atacama.
TolTEC Camera on UMass Amherst and Mexico’s Instituto Nacional de Astrofísica, Óptica y Electrónica Large Millimeter Telescope IIAlfonso Serrano, Mexico, at an altitude of 4850 meters on top of the Sierra Negra.
Primordial Inflation Polarization Explorer (PIPER) millimeter-wave telescope on a high-altitude scientific balloon program designed to fly for the purpose investigate the nascent stages of the universe.
They are now producing lenses for the Simons Observatory, which will start collecting data next year.
LBL The Simons Array in the Atacama in Chile, altitude 5,200 m (17,100 ft) with the 6 meter Atacama Cosmology Telescope.
From there, they will begin making additional lenses for CMB-S4 (Cosmic Microwave Background Stage 4), a next-generation project of which Fermilab is a member. CMB-S4 is scheduled to begin collecting data in 2027 using 21 telescopes at observatories in Chile and the South Pole for the most detailed CMB survey yet.
CMB-S4 is the next-generation ground-based cosmic microwave background experiment. With 21 telescopes at the South Pole and in the Chilean Atacama desert surveying the sky with 550,000 cryogenically-cooled superconducting detectors for 7 years CMB-S4 will deliver transformative discoveries in fundamental physics, cosmology, astrophysics, and astronomy. CMB-S4 is supported by the Department of Energy Office of Science and the National Science Foundation.
“The second we finish a lens, it’s doing science, and that’s what makes it fun for me,” McMahon said. “All the metamaterial stuff is cool, but at the end of the day I just want to figure out how the universe began and what’s in it.”
McMahon compares CMB-S4 to opening a treasure chest full of gold and jewels. He and the other researchers contributing to it don’t know exactly what they’ll find in the data, but they know it will be valuable. Even if they don’t find primordial gravitational waves — one of the project’s major goals — the experiment will still shed light on cosmic mysteries such as dark energy, dark matter and neutrino masses.
What his team has achieved with their lens technology, McMahon says, is a testament to the outsize effect small efforts can have on big science.
“The endeavor is to begin to understand the beginning of the universe,” he said. “And the way we’re doing it is by figuring out how to machine little features in silicon.”
This work is supported by the Department of Energy Office of Science.
Fermi National Accelerator Laboratory(US), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
collaborate at Fermilab on experiments at the frontiers of discovery.
Don Lincoln-Fermi National Accelerator Laboratory.
Illustration of the expansion of the Universe. The Cosmos began 13.7 billion years ago in an event dubbed the Big Bang (left). Immediately it began expanding and cooling (stage 1). Eventually, the universe became transparent to radiation, and the first matter was able to form into clumps. Its expansion slowed about 10 billion years ago (stage 2). At stage 3, 5 billion years ago, the universe was full of stars and galaxies, and its expansion began to speed up again because of the mysterious Dark Energy that pervades the Universe. We are now at stage 4, and the expansion shows no signs of stopping and is in fact accelerating. The orange arrows indicate the force of gravity. This slows the expansion but cannot at present halt it. Credit: Getty.
Cosmologists are perplexed. They believe they have a good understanding of the origins of the universe and how it has evolved since the beginning. However, two measurements of the speed at which the universe is currently expanding disagree and that could be the first signs that they will have to make significant changes to their understanding of the cosmos.
A recent measurement [Cosmic Distances Calibrated to 1% Precision with Gaia EDR3 Parallaxes and Hubble Space Telescope Photometry of 75 Milky Way Cepheids Confirm Tension with LambdaCDM] has deepened the controversy. The dispute is basically simple. Scientists used two ways to determine the current expansion speed of the universe. The first involves making measurements of the conditions of the universe when it began and then using well accepted theory to predict today’s expansion rate. The second is to simply measure the rate today. If everything hangs together, the two numbers should agree. But they don’t.
Full-Sky Map Of Cosmic Background Radiation, A Full-Sky Map Produced By The Wilkinson Microwave Anisotropy Probe (WMAP) Showing Cosmic Background Radiation, A Very Uniform Glow Of Microwaves Emitted By The Infant Universe More Than 13 Billion Years Ago. Credit: Universal Images Group via Getty Images.
NASA WMAP satellite 2001 to 2010.
CMB per ESA/Planck.
ESA/Planck 2009 to 2013
Predicting the current expansion rate of the universe using ancient data is complicated. The ancient data includes the cosmic microwave background, which is a radio signal that is essentially the cooled fireball of the Big Bang. Other data includes the pattern of how galaxies gathered over time [The Millennium Simulation Project- MPG Institute for Astrophysics [MPG Institut für Astrophysik], Garching (DE)]. For instance, did galaxies tend to cluster together, leaving voids? Or were they dispersed uniformly? And how did those patterns change over billions of years?
A simulation of the matter of the universe is distributed on vast ribbons, surrounded by empty voids. The distances seen here span hundreds of millions of light years. Credit: Volker Springel/Max Planck Institute For Astrophysics/SPL.
Astronomers take all of those measurements and more, and combine them with a sophisticated theory of the evolution of the universe to predict a rate at which the universe should currently be expanding. They predict that the expansion rate of the universe should be 67.4 ± 0.5 kilometers per second per megaparsec distance. A megaparsec is 3.26 million light years. This means that a galaxy a megaparsec away from Earth should be moving away at 67.4 km/s, while a galaxy two megaparsecs away should be moving away from us at a speed of 134.8 km/s.
However, astronomers can also directly measure the expansion rate, simply by looking at galaxies within a few million light years and they find a much larger expansion rate. The directly measured expansion rate is 73.2 ± 1.3 km/s per megaparsec.
The crux of the disagreement is that 67.4 ± 0.5 and 73.2 ± 1.3 disagree.
So, what can explain this disagreement? Well, each method has assumptions and limitations that should be revisited. For instance, when astronomers measure the expansion rate of the universe today, they look at individual galaxies and determine each galaxy’s speed and distance. The speed is easy to determine. Astronomers use what is called the Doppler effect. This effect makes galaxies moving away from the Earth look redder than they would if they were stationary. Furthermore, the faster they are moving, the redder they appear. Color is easy to measure, so we know each galaxy’s speed very well.
Illustration of a supernova explosion which is bright enough to be seen across the universe. Credit: Tobias Roetsch/Future Publishing via Getty Images.
But a galaxy’s distance is much more difficult. In fact, it has taken over a century to work out a method for determining cosmic distances. For short distances – say 10 – 100 light years, astronomers use triangulation. They look at the location of a nearby star on one night and then again six months later. If the star is relatively nearby, its location will appear different compared to more distant stars. And by using the diameter of the Earth’s orbit, along with the very small different positions the nearby star appears, astronomers can work out the star’s distance.
For more distant stars or galaxies, scientists use stars or supernovae of known intrinsic brightness. By comparing the object’s intrinsic brightness with the observed brightness in our telescopes, we can work out its distance. For objects that are thousands to a few million light years away, astronomers use a type of stars call Cepheid variables, which vary in brightness. The intrinsic brightness of the star is related to the amount of time between consecutive bright periods. For objects that are millions to billions of light years away, astronomers use a class of supernovae called Type Ia. These are stars that explode with an intrinsic brightness that is something scientists can determine.
The entire spectrum of distances is tied together. Astronomers use triangulation on nearby Cepheid variable stars to determine their intrinsic brightness. They then look at Cepheid variable stars in nearby galaxies in which Type Ia supernovae have occurred to determine the supernovae’s intrinsic brightness. This interconnectivity is called the cosmic ladder, where each distance scale is connected to the one below it.
So, this means that everything is tied to getting a firm grasp on triangulating the distance to nearby stars. If that’s wrong, all other distance scales are also wrong.
In 2013, the European Space Agency launched the Gaia mission.
ESA (EU)/GAIA satellite .
Gaia is a space platform that is able to measure the location of nearby stars with unprecedented precision. The spacecraft has many missions, for example, making a precise 3D map of the nearby parts of the Milky Way galaxy. However, a group of astronomers have also used the data set to very precisely determine the distances to nearby Cepheid variable stars. This, in turn, results in a precise determination of the current expansion rate of the universe, specifically 73.2 ± 1.3 km/s per megaparsec, with a precision of 1.8%. This is to be contrasted with an earlier estimate of 74.03 ± 1.42 km/s per megaparsec. The precision of this earlier estimate was 1.9%. Furthermore, the researches expect that the Gaia data will allow them to eventually achieve a precision of 1%.
So, it appears that there is a real and significant difference between the direct measurement of the current expansion rate of the universe and a prediction using data from billions of years ago.
Turning to the prediction using data from the dawn of the cosmos, what sorts of weaknesses does that effort have? Well, for one, it assumes that our accepted theory of the evolution of the universe is correct. However, it is entirely possible that this theory doesn’t include unknown phenomena. Suppose, for example, that during the first million or so years after the Big Bang there was a period where gravity didn’t slow down the expansion of the universe, but briefly sped it up [Physics-Dark Energy Solution for Hubble Tension June 4, 2019. Metaphorically, if the expansion rate of the universe was a car, perhaps something stepped on the accelerator for a short period of time.
The idea of a brief period of early accelerated expansion would require some unknown physics and would require a modification of the theory of the evolution of the universe. This is by no means universally accepted, but it is a possible solution of the disagreement between two methods of measuring the current expansion rate of the universe.
And, of course, other scientists are trying to find other ways of measuring this rate. For instance, while the traditional way of setting the first rung of the cosmic ladder is using Cepheid variable stars, other astronomers are attempting to use [Quanta] other approaches, for example using RR Lyrae stars, tip-of-the-red-giant-branch stars, and so-called carbon stars.
We don’t know how this cosmic discrepancy will be resolved, but it appears to be a real cause for concern. On the mundane side, it could be that there is a conceptual error in one or more of the current analyses. On the exciting side, it could be that there is more to learn about the evolution history of the cosmos. We’ll just have to wait for the answer.
While a zoomed-out picture of the universe looks fairly uniform, it does have a large-scale structure, for example because galaxies and dark matter are not uniformly distributed throughout the universe. The origin of this structure has been traced back to the tiny inhomogeneities observed in the Cosmic Microwave Background (CMB)—radiation that was emitted when the universe was 380 thousand years young that we can still see today. But the CMB itself has three puzzling features that are considered anomalies because they are difficult to explain using known physics.
“While seeing one of these anomalies may not be that statistically remarkable, seeing two or more together suggests we live in an exceptional universe,” said Donghui Jeong, associate professor of astronomy and astrophysics at Penn State and an author of the paper. “A recent study in the journal Nature Astronomy proposed an explanation for one of these anomalies that raised so many additional concerns, they flagged a ‘possible crisis in cosmology.’ Using quantum loop cosmology, however, we have resolved two of these anomalies naturally, avoiding that potential crisis.”
Research over the last three decades has greatly improved our understanding of the early universe, including how the inhomogeneities in the CMB were produced in the first place. These inhomogeneities are a result of inevitable quantum fluctuations in the early universe. During a highly accelerated phase of expansion at very early times—known as inflation—these primordial, miniscule fluctuations were stretched under gravity’s influence and seeded the observed inhomogeneities in the CMB.
“To understand how primordial seeds arose, we need a closer look at the early universe, where Einstein’s theory of general relativity breaks down,” said Abhay Ashtekar, Evan Pugh Professor of Physics, holder of the Eberly Family Chair in Physics, and director of the Penn State Institute for Gravitation and the Cosmos. “The standard inflationary paradigm based on general relativity treats space time as a smooth continuum. Consider a shirt that appears like a two-dimensional surface, but on closer inspection you can see that it is woven by densely packed one-dimensional threads. In this way, the fabric of space time is really woven by quantum threads. In accounting for these threads, loop quantum cosmology allows us to go beyond the continuum described by general relativity where Einstein’s physics breaks down—for example beyond the Big Bang.”quantum cosmology—a theory that uses quantum mechanics to extend gravitational physics beyond Einstein’s theory of general relativity—accounts for two major mysteries. While the differences in the theories occur at the tiniest of scales—much smaller than even a proton—they have consequences at the largest of accessible scales in the universe. The study, which appears online July 29, 2020 in the journal Physical Review Letters, also provides new predictions about the universe that future satellite missions could test.
CMB per ESA/Planck
ESA/Planck 2009 to 2013
Diagram showing evolution of the Universe according to the paradigm of Loop Quantum Origins, developed by scientists at Penn State. Image credit: Alan Stonebraker. P. Singh, Physics 5, 142 (2012); APS/A. Stonebraker.
The researchers’ previous investigation into the early universe replaced the idea of a Big Bang singularity, where the universe emerged from nothing, with the Big Bounce, where the current expanding universe emerged from a super-compressed mass that was created when the universe contracted in its preceding phase. They found that all of the large-scale structures of the universe accounted for by general relativity are equally explained by inflation after this Big Bounce using equations of loop quantum cosmology.
In the new study, the researchers determined that inflation under loop quantum cosmology also resolves two of the major anomalies that appear under general relativity.
“The primordial fluctuations we are talking about occur at the incredibly small Planck scale,” said Brajesh Gupt, a postdoctoral researcher at Penn State at the time of the research and currently at the Texas Advanced Computing Center of the University of Texas at Austin. “A Planck length is about 20 orders of magnitude smaller than the radius of a proton. But corrections to inflation at this unimaginably small scale simultaneously explain two of the anomalies at the largest scales in the universe, in a cosmic tango of the very small and the very large.”
The researchers also produced new predictions about a fundamental cosmological parameter and primordial gravitational waves that could be tested during future satellite missions, including LiteBird and Cosmic Origins Explorer, which will continue improve our understanding of the early universe.
In addition to Jeong, Ashtekar, and Gupt, the research team includes V. Sreenath at the National Institute of Technology Karnataka in Surathkal, India. This work was supported by the National Science Foundation, NASA, the Penn State Eberly College of Science, and the Inter-University Center for Astronomy and Astrophysics in Pune, India.
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Members of the BICEP collaboration enjoying an Antarctic summer day in front of the new BICEP Array Telescope at the South Pole. Clem Pryke
Professor Clem Pryke and his group are on their way back to Minnesota from the South Pole in Antarctica after completing installation of the new BICEP Array Telescope. Over the next few years this specialized radio telescope will study the Cosmic Microwave Background [CMB] – an afterglow from the Big Bang – looking for the imprint of gravitational waves from the beginning of time.
CMB per ESA/Planck
The project, which has been several years in the making, is a collaboration between the University of Minnesota, Caltech, Harvard and Stanford.
The telescope mount is a large, custom built machine which moves and points the radio receivers on the sky. The pieces of the apparatus were delivered to a large assembly hall at the University of Minnesota in the summer of 2018. There then followed an intensive year-long process of turning the raw platform into a fully-fledged telescope complete with drive system, receivers, cryogenic refrigerators, electronics and environmental protection equal to the extreme polar temperatures (-30F in summer and -110F in winter). Then, late last summer, the entire system was broken back down into component parts, packed into crates, and shipped out to the South Pole (via California, New Zealand and McMurdo Station on the coast of Antarctica).
At the South Pole there is one day-night cycle per year and the Station is accessible only during the southern hemisphere summer (from November to February). During this period the on-site team reassembled the new telescope and and brought all of the complex supporting systems online.
Now with the departure of the main team, a single UMN scientist will remain through the six month Antarctic winter night to keep the telescope operating as it records its scientific data. The new telescope is the most sensitive of its type in the world and will continue the quest to understand the physics which governed the very beginning of our universe.
The University of Minnesota, Twin Cities (often referred to as the U of M, UMN, Minnesota, or simply the U) is a public research university in Minneapolis and Saint Paul, MN. The Twin Cities campus comprises locations in Minneapolis and St. Paul approximately 3 miles (4.8 km) apart, and the St. Paul location is in neighboring Falcon Heights. The Twin Cities campus is the oldest and largest in the University of Minnesota system and has the sixth-largest main campus student body in the United States, with 51,327 students in 2019-20. It is the flagship institution of the University of Minnesota System, and is organized into 19 colleges, schools, and other major academic units.
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Alan Guth’s original notes on inflation.
Dean Osgood are discussing. 
sciencesprings 
Dean Osgood 10:04 pm on February 5, 2023 Permalink |
Long time no contact.
I only check emails at most once a day.
I prefer texting
We are well and enjoying our mountain top
Take care
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richardmitnick 11:31 am on February 6, 2023 Permalink |
Great to hear from you. I just spoke on the phone at length with Gail. My Facebook page has been ruined by Facebook, presenting to me only “Suggested for you” and leaving no blank box in which to write. I do see your posts via email and am able to respond to them, but I cannot originate anything. This is a find a wide spread problem with solution or option to remove. zi learned that one can try on a different browser and I did and it worked for a while but then also presented only ” Suggested for you”. Facebook was my connection to you and the Silver Springs relatives since I do not travel. I am hoping this will end. Thanks a lot, Facebook.
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