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  • richardmitnick 6:06 pm on May 22, 2017 Permalink | Reply
    Tags: , , , , , , Meet the Biggest Censor of All: the Universe, Physics   

    From AIP via Inside Science: “Meet the Biggest Censor of All: the Universe” 

    AIP Publishing Bloc

    American Institute of Physics

    1

    Inside Science

    Theoretical physicists contemplate the seemingly impossible situation of a point in space-time where gravity goes to infinity.

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    Image credits: Animated image by Yuen Yiu, Staff Writer (Source image, credit: Ute Kraus) Rights information: CC BY-SA 2.5

    May 18, 2017
    Yuen Yiu

    What exists inside black holes? Wormholes? Entire universes? The back of a bookcase ? Since nothing can communicate from inside a black hole to the outside world, we may never know for sure. But even if astrophysicists can’t directly see what’s going on behind the curtains of black holes, they can still make guesses.

    One particular item of interest is the concept of a gravitational singularity — a hypothetical point in space-time where gravity would go to infinity. Even though Albert Einstein’s theory of general relativity predicts the existence of singularities inside black holes, it can’t describe what actually happens at those points. This gap in our understanding of the universe is like a plot hole where a writer introduces a monster in the first chapter, but somehow can’t describe what the monster does at all — it’s a Chekhov’s gun that leaves us all hanging.

    Research in astrophysics is often limited by the amount of data that scientists can gather from space. Oftentimes that is simply because we can’t build instruments powerful enough to detect these events in our universe, but other times the information we want to gather is guarded by the laws of physics. For instance, any information that exists within the event horizon of a black hole simply cannot escape the black hole’s gravitational pull and reach us, no matter how much better our telescopes can get. In order to try making sense of it all, theoretical physicists are using a multitude of complex mathematical tools to explore what exactly happens in the strange and well-hidden areas of the universe.

    A mathematical conundrum posited by Einstein

    “Einstein’s equations [of general relativity] predict that singularities will form under certain circumstances — places where the equations break down, and the gravitational fields become infinite,” said Toby Crisford, a doctoral student in theoretical physics at the University of Cambridge in England.

    If a gravitational singularity existed near Earth, the deterministic nature of our laws of physics would break down. Then, literally anything could happen — a black hole appearing out of nowhere, time flowing backwards or even the sun transforming to become the head of a baby. Since this doesn’t make sense — even though it is allowed by Einstein’s theory of general relativity — scientists are trying to come up with explanations that can reconcile the concept of singularities with Einstein’s equations, and of course, with reality.

    One leading conjecture to remedy this conundrum is known as cosmic censorship. Proposed in 1969 by famous British theoretical physicist Roger Penrose, the conjecture argues that no singularities — except that of the Big Bang — can be observed from the rest of space-time. Therefore, Penrose believes that if singularities existed in our universe, they would always be sealed inside black holes, or as he calls it — cosmically censored.

    If this is true, then even if singularities existed, their effects would be confined to within the black holes that house them, where other exotic physics such as the yet-to-be understood quantum gravity can take over, and the plot hole introduced by Einstein’s equations will finally be patched up, more than 100 years since its creation.

    While most scientists are fairly confident that the conjecture is true — since we haven’t yet detected a singularity — definitive proof remains at large, nearly 50 years since Penrose first questioned Einstein’s predictions. Since an experimental approach is almost impossible, physicists have been looking into theoretical scenarios in which so-called naked singularities could defy the conjecture, within universes with all kinds of weird dimensionalities or space-time curvatures that are different from our own.

    A naked singularity, uncensored

    “There have been counter examples to the cosmic censorship conjecture in higher dimensions,” said Crisford, such as the five dimensional ring black holes that theorists modeled to explore specific scenarios where naked singularities could sit unmasked in space-time, without a surrounding black hole.

    According to Ivan Agullo, a theoretical physicist from Louisiana State University in Baton Rouge, calculations about singularities are often so difficult that theorists can only look for solutions in certain set ups, such as space-time with a specific curvature or even in different dimensions. This is similar to how physicists often leave out certain variables when estimating the path of a projectile, because exact solutions can be extremely complicated if all variables are to be considered, such as aerodynamics, variations in gravity or even the Coriolis effect.

    “What we can do is to accumulate knowledge, by testing these arguments in scenarios where the equations are actually solvable,” Agullo said.

    The latest paper by Crisford’s group, published May 2 in the journal Physical Review Letters, takes a new approach to the problem. It presents a counterexample to Penrose’s conjecture, but in four dimensions — three of space and one of time. It is the first time anyone has mathematically constructed a naked singularity within a 4-D space-time. However, the negatively curved space-time they used in their calculations — known as anti-de Sitter space — is still quite different from our 4-D reality, and the curvature of space-time itself also remains a hotly debated topic.

    “But I guess [our calculation] is one step closer to reality,” Crisford said.

    Other researchers are taking a different approach that looks beyond what’s ordinarily prescribed in Einstein’s general relativity equations.

    A mysterious quantum dress

    An international collaboration among theoretical physicists from Brazil, Italy and Chile looked into the effects generated at the quantum level by the matter surrounding singularities. Their paper, published in March, also in Physical Review Letters, claims that these quantum effects can create the event horizon that shields an otherwise naked singularity from outside observers, even when the naked singularity exists as a solution to the classical Einstein equations.

    First, they began with a model where a rotating naked singularity exists in three-dimensional space-time — two in space and one in time. They discovered that as soon as the model was modified to include additional quantum effects, an event horizon formed around the singularity — or a “quantum dress,” as they called it [Science Direct].

    They also looked into a different scenario, where they started the model with a rotating black hole right off the bat. In this case, they found the inclusion of quantum effects led to an instability inside the black hole. This instability, they suspect, might be able to preserve the laws of physics that would otherwise stop making sense, or more specifically, the predictability of the physics inside the black hole. While quantum effects seem like a blanket term for many different physical phenomena, here the key effect at play is a concept conceived by Stephen Hawking in 1974, known as Hawking radiation.

    “A perhaps cartoonish way of understanding Hawking radiation, is that according to quantum physics, even if in vacuum, there’re constantly particles and anti-particles being created,” said Marc Casals, one of the authors of the paper and a theoretical physicist at the Brazilian Center for Research in Physics in Rio de Janeiro. “When this happens near a black hole, one of them can fall into the black hole, and the other one can escape, and it’ll look like the black hole is emitting out radiation.”

    In extreme situations, effects that seem negligible can become significant, just like how special relativity explains why the clocks on board GPS satellites slow down at high orbital speeds. Unless you live on a space station they won’t affect the watch on your wrist nearly as much.

    Similarly, scientists believe that Hawking radiation, though rooted in tiny quantum effects, plays a very important role in the physics of black holes. Even though this all sounds highly theoretical and technical, experimentalists are actively trying to directly observe these effects here on Earth. You might have heard the claim that scientists at the Large Hadron Collider in Europe might create a scary microscopic black hole here on Earth. This led to minor hysteria from members of the public who feared a doomsday scenario where the black hole would devour the planet. In that specific scenario, Hawking radiation is the key effect that will cause the tiny black hole to disintegrate within a tiny fraction of a second, way before any damage could be done.

    To quantum and beyond

    Studies of black holes, naked singularities and other exotic phenomenon could help researchers understand what is often the most difficult of the four fundamental forces to grasp: gravity. Gravity is by far the weakest force, and its close tie to general relativity definitely doesn’t make it any easier to understand. While all the other three forces — weak, strong and electromagnetic — have been unified under quantum field theory, gravity remains stranded by itself, as the last elusive piece in the search for a “theory of everything.”

    “We know that general relativity is not a complete theory of everything,” Crisford said.

    Within the Big Bang and black holes lie the keys scientists need to fully understand gravity. However, the same gravity that makes black holes interesting also prevents us from looking into them — by creating event horizons that make up the black holes in the first place. The concepts of singularities and cosmic censorship, tangled up with the rest of these mysteries, represent holes in the incomplete puzzle for the “theory of everything.” Will physicists ever find the missing pieces? Nobody knows for sure.

    One way scientists are advancing the quest is with quantum gravity, a field still in its relative infancy. A complete theory of gravity, which quantum gravity might provide, would not only tell us what happens at the center of black holes, but also likely fill in the plot holes in the current understanding of the universe.

    “In order to tackle cosmic censorship completely, ultimately we will need to understand quantum gravity,” said Agullo. “But it’s a very difficult topic.”

    See the full article here .

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    AIP Building

    AIP serves a federation of physical science societies in a common mission to promote physics and allied fields.

     
  • richardmitnick 9:28 am on May 22, 2017 Permalink | Reply
    Tags: , , Bose–Einstein condensates simulate transformation of elusive magnetic monopoles, , Dirac monopole, , Physics   

    From COSMOS: “Bose–Einstein condensates simulate transformation of elusive magnetic monopoles” 

    Cosmos Magazine bloc

    COSMOS

    22 May 2017
    Robyn Arianrhod

    For the first time physicists have experimentally simulated a long-predicted relationship between two kinds of magnetic monopole.

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    Left: The quantum monopole. Right: the Dirac monopole. The different colors represent the direction of the internal magnetic state of the atoms and the brightness corresponds to particle density.
    Tuomas Ollikainen

    A team of physicists led by David Hall from Amherst College, USA, and Mikko Möttömen from Aalto University, Finland, has experimentally demonstrated the relationship between two different analogues of magnetic monopoles. The results, published in Physical Review X, provide the first demonstration of quantum monopole dynamics.

    The new research builds on a decade of earlier work, by Hall and Möttömen as well as by other teams, which focused on trying to synthesize monopole analogues in the first place.

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    No image credit. http://io9.gizmodo.com/5620547/ask-a-physicist-what-ever-happened-to-magnetic-monopoles

    Real magnetic monopoles – the magnetic counterparts of electrons and protons, the fundamental negative and positive electric charges that make up the atoms in our universe – have yet to be observed. Magnets always have two poles, north and south, and so far no amount of metaphorical slicing and dicing has been able to isolate separate north and south poles: rather, cutting a magnet in two simply produces two magnets, each with a north and a south pole.

    This asymmetry between electricity and magnetism has long puzzled physicists. It also spoils the beauty of James Clerk Maxwell’s celebrated 1864 equations of electromagnetism. But there is no theoretical reason not to put the symmetry back into Maxwell’s equations, by adding in magnetic “charges” (monopoles) analogous to the electric charges, and in 1931, pioneering British quantum physicist Paul Dirac showed how to reinterpret the relevant quantum mechanical equations in this light. He found that the force between two opposite magnetic monopoles would be nearly 5000 times as strong as the force between an electron and a proton. No wonder, he mused, that no-one has yet been able to separate magnetic poles. Which is why physicists have recently turned to simulating monopoles.

    “My feeling is that some of the details associated with the Dirac monopole are not fully appreciated by the wider physics community,” says Hall. Experiments can help physicists to better understand this elegant theory, and ultimately, perhaps, point to ways of discovering whether or not real monopoles exist. But there are also potential practical benefits.

    Back in 2009, Jonathan Morris was part of a team from Berlin’s Helmholtz Centre that found magnetic monopole analogues in strange structures known as “spin-ice”, and he believes we could be in for a slew of new technologies using simulated monopoles. But first, he cautions, “we must get to the bottom of how monopoles behave”.

    And that means spending many hours in the lab – hours that often involve “a lot of unglamorous day-to-day problem-solving,” as Hall puts it. Working out how to remove “noise” from everyday magnetic fields created by overhead power lines, computers, and the Earth itself was a real headache in the early research, Hall laments; in these latest delicate experiments, even something as simple as a pair of steel scissors had to be banned from the lab.

    To isolate and study their monopole analogues, Hall, Möttönen and their colleagues used a cloud of extremely cold rubidium atoms.

    (This is known as a Bose–Einstein condensate, or BEC for short.

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    Condensed matter physics
    Phase diagram of a second order quantum phase transition
    Author DG85

    Theoretically predicted in 1924, the first BEC was not actually made until 1995; its creators received the 2001 Nobel Prize for physics. Following in their footsteps, Hall and his undergraduate students at Amherst made their own atomic refrigerator in 2002, and it is still going strong.)

    A BEC acts as a sort of magnifying glass, because the cloud of atoms, cooled to almost absolute zero, behaves in just the same way as if it were a single quantum particle. This “magnification” makes it possible to observe and photograph the way a BEC “electron” behaves in a simulated magnetic monopolar field, or the way a “monopole” forms. It’s about making a model of something that is not really electromagnetic, but which behaves just the way quantum mechanics says that an electron or a magnetic monopole should behave.

    By contrast, a number of international teams have found that “spin-ice” does seem to contain a lattice of monopoles that are really magnetic, although they, too, are analogues of the free-moving real monopoles that would parallel electrons and protons. Each experimental analogue adds to physicists’ knowledge, and in the latest research, Hall, Möttönen and their colleagues have taken their model to a new level by demonstrating the relationship between analogues of Dirac monopoles and “isolated” or “topological” monopoles.

    Predicted by t’Hooft and Polyakov in 1974, an “isolated” monopole is mathematically different from Dirac’s version, but theory says that at a suitable distance it effectively becomes a Dirac monopole.

    Hall’s team began by allowing a simulated “isolated” monopole to evolve in time.

    “This is where noise can really wreak havoc,” says Hall. “The problem is compounded because to study the process over time, we don’t simply take a movie of a sample, one frame after the other, but we have to take each frame with a different sample, waiting a little longer after the creation [of the isolated monopole analogue] to take each successive frame. It’s as if you create the movie set, take a picture, and then the set is destroyed. Then you recreate the set, wait a little longer, take the picture, and it is destroyed again. It’s annoying enough to have to recreate the set every time you need another frame of the movie. Now imagine that every time the director calls ‘Action!’ the scene props are being blown randomly all over the place because it is violently windy.” The winds are the “noise” that needs to be filtered out before the data can be interpreted.

    But these laborious experiments have hit paydirt: for the first time, physicists have observed the spontaneous creation of a Dirac monopole analogue from the decay of a simulated t’Hooft–Polyakov monopole.

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    Artistic view of the decay of a quantum-mechanical monopole into a Dirac monopole. Credit: Heikka Valja. phys.org

    “I was jumping in the air the first time I saw it,” says Möttönen. As for Hall, “I knew to expect this from the theory, but to see it in the data – that was pretty wild. It felt like watching a sculpture take form from a block of marble.”

    See the full article here .

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  • richardmitnick 8:43 pm on May 21, 2017 Permalink | Reply
    Tags: , , , , , , NanoFab, , Physics   

    From NIST: “Nanocollaboration Leads to Big Things” 

    NIST

    May 12, 2017 [Nothing like being timely getting into social media.]

    Ben Stein
    benjamin.stein@nist.gov
    (301) 975-2763

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    Entrance to NIST’s Advanced Measurement Laboratory in Gaithersburg, Maryland. Credit: Photo Courtesy HDR Architecture, Inc./Steve Hall Copyright Hedrich Blessing

    Roche Sequencing Solutions engineer Juraj Topolancik was looking for a way to decode DNA from cancer patients in a matter of minutes.

    Rajesh Krishnamurthy, a researcher with the startup company 3i Diagnostics, needed help in fabricating a key component of a device that rapidly identifies infection-causing bacteria.

    Ranbir Singh, an engineer with GeneSiC Semiconductor Inc., in Dulles, Virginia, sought to construct and analyze a semiconductor chip that transmits voltages large enough to power electric cars and spacecraft.

    These researchers all credit the NanoFab, located at the Center for Nanoscale Science and Technology (CNST) on the Gaithersburg, Maryland campus of the National Institute of Standards and Technology (NIST). The NanoFab provides cutting-edge nanotechnology capabilities for NIST scientists that is also accessible to outside users, with supplying the state-of-art tools, know-how and dependability to realize their goals.


    Learn more about the CNST NanoFab, where scientists from government, academia and industry can use commercial, state-of-the-art tools at economical rates, and get help from dedicated, full-time technical support staff. Voices: David Baldwin (Great Ball of Light, Inc.), Elisa Williams (Scientific & Biomedical Microsystems), George Coles (Johns Hopkins Applied Physics Laboratory) and William Osborn (NIST).

    When Krishnamurthy, whose company is based in Germantown, Maryland, needed an infrared filter for the bacteria-identifying chip, proximity was but one factor in reaching out to the NanoFab.

    “Even more important was the level of expertise you have here,” he says. “The attention to detail and the trust we have in the staff is so important—we didn’t have to worry if they would do a good job, which gives us tremendous peace of mind,” Krishnamurthy notes.

    The NanoFab also aided his project in another, unexpected way. Krishnamurthy had initially thought that the design for his company’s device would require a costly, highly customized silicon chip. But in reviewing design plans with engineers at the NanoFab, “they came up with a very creative way” to use a more standard, less expensive silicon wafer that would achieve the same goals, he notes.

    “The impact in the short term is that we didn’t have to pay as much [to build and test] the device at the NanoFab, which matters quite a bit because we’re a start-up company,” says Krishnamurthy. “In the long run, this will be a huge factor in [enabling us to mass produce] the device, keeping our costs low because, thanks to the input from the NanoFab, the source material is not a custom material.”

    Singh came to the NanoFab with a different mission. His company is developing a gallium nitride semiconductor device durable enough to transmit hundreds to thousands of volts without deteriorating. He relies on the NanoFab’s metal deposition tools and high-resolution lithography instruments to finish building and assess the properties of the device.

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    Semiconductor device, fabricated with the help of the NanoFab, designed to transmit high voltages.
    Credit: GeneSiC Semiconductor Inc.

    “Not only is there a wide diversity of tools, but within each task there are multiple technologies,” Singh adds.

    For instance, he notes, technologies offered at the NanoFab for depositing exquisitely thin and highly uniform layers of metal—which Singh found crucial for making reliable electrical contacts—include both evaporation and sputtering, he says.

    The wide range of metals available for deposition at the NanoFab, uncommon at other nanotech facilities, was another draw.

    “We needed different metals compared to those commonly used on silicon wafers and the NanoFab provided those materials,” notes Singh.

    Topolancik, the Roche Sequencing Solutions engineer, needed high precision etching and deposition tools to fabricate a device that may ultimately improve cancer treatment. His company‘s plan to rapidly sequence DNA from cancer patients could quickly determine if potential anti-cancer drugs and those already in use are producing the genetic mutations necessary to fight cancer.

    “We want to know if the drug is working, and if not, to stop using it and change the treatment,” says Topolancik.

    In the standard method to sequence the double-stranded DNA molecule, a strand is peeled off and resynthesized, base by base, with each base—cytosine, adenine, guanine and thymine—tagged with a different fluorescent label.

    “It’s a very accurate but slow method,” says Topolancik.

    Instead of peeling apart the molecule, Topolancik is devising a method to read DNA directly, a much faster process. Borrowing a technique from the magnetic recording industry, he sandwiches the DNA between two electrodes separated by a gap just nanometers in width.

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    Illustration of experiment to directly identify the base pairs of a DNA strand (denoted by A, C, T, G in graph). Tunneling current flows through DNA placed between two closely spaced electrodes. Different bases allow different amounts of current to flow, revealing the components of the DNA molecule.
    Credit: J. Topolancik/Roche Sequencing Solutions

    According to quantum theory, if the gap is small enough, electrons will spontaneously “tunnel” from one electrode to the other. In Topolancik’s setup, the tunneling electrons must pass through the DNA in order to reach the other electrode.

    The strength of the tunneling current identifies the bases of the DNA trapped between the electrodes. It’s an extremely rapid process, but for the technique to work reliably, the electrodes and the gap between them must be fabricated with extraordinarily high precision.

    That’s where the NanoFab comes in. To deposit layers of different metals just nanometers in thickness on a wafer, Topolancik relies on the NanoFab’s ion beam deposition tool. And to etch a pattern in those ultrathin, supersmooth layers without disturbing them—a final step in fabricating the electrodes—requires the NanoFab’s ion etching instrument.

    “These are specialty tools that are not usually accessible in academic facilities, but here [at the NanoFab] you have full, 24/7 access to them,” says Topolancik. “And if a tool goes down, it gets fixed right away,” he adds. “People here care about you, they want you to succeed because that’s the mission of the NanoFab.” As a result, he notes, “I can get done here in two weeks what would take half a year any place else.”


    Take a 360-degree walking tour of the CNST NanoFab in this video!

    See the full article here.

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    NIST Campus, Gaitherberg, MD, USA

    NIST Mission, Vision, Core Competencies, and Core Values

    NIST’s mission

    To promote U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology in ways that enhance economic security and improve our quality of life.
    NIST’s vision

    NIST will be the world’s leader in creating critical measurement solutions and promoting equitable standards. Our efforts stimulate innovation, foster industrial competitiveness, and improve the quality of life.
    NIST’s core competencies

    Measurement science
    Rigorous traceability
    Development and use of standards

    NIST’s core values

    NIST is an organization with strong values, reflected both in our history and our current work. NIST leadership and staff will uphold these values to ensure a high performing environment that is safe and respectful of all.

    Perseverance: We take the long view, planning the future with scientific knowledge and imagination to ensure continued impact and relevance for our stakeholders.
    Integrity: We are ethical, honest, independent, and provide an objective perspective.
    Inclusivity: We work collaboratively to harness the diversity of people and ideas, both inside and outside of NIST, to attain the best solutions to multidisciplinary challenges.
    Excellence: We apply rigor and critical thinking to achieve world-class results and continuous improvement in everything we do.

     
  • richardmitnick 8:26 pm on May 21, 2017 Permalink | Reply
    Tags: , , Interactions.org, Laboratori Nazionali del Gran Sasso - INFN, Physics, ,   

    From interactions.org: “XENON1T, the most sensitive detector on Earth searching for WIMP dark matter, releases its first result” 

    Interactions.org

    Laboratori Nazionali del Gran Sasso – INFN

    18 May 2017
    Contact:

    XENON spokesperson
    Prof. Elena Aprile, Columbia University, New York, US.
    Tel. +39 3494703313
    Tel. +1 212 854 3258
    age@astro.columbia.edu

    INFN spokesperson
    Roberta Antolini
    + 39 0862 437216
    Roberta.antolini@lngs.infn.it

    Gran Sasso LABORATORI NAZIONALI del GRAN SASSO, located in the Abruzzo region of central Italy

    INFN Gran Sasso ICARUS, since moved to FNAL

    “The best result on dark matter so far! … and we have just started!”

    This is how scientists behind XENON1T, now the most sensitive dark matter experiment world-wide, hosted in the INFN Laboratori Nazionali del Gran Sasso, Italy, commented on their first result from a short 30-day run presented today to the scientific community.

    XENON1T at Gran Sasso

    Dark matter is one of the basic constituents of the Universe, five times more abundant than ordinary matter. Several astronomical measurements have corroborated the existence of dark matter, leading to a world-wide effort to observe directly dark matter particle interactions with ordinary matter in extremely sensitive detectors, which would confirm its existence and shed light on its properties. However, these interactions are so feeble that they have escaped direct detection up to this point, forcing scientists to build detectors that are more and more sensitive. The XENON Collaboration, that with XENON100 led the field for years in the past, is now back on the frontline with XENON1T. The result from a first short 30-day run shows that this detector has a new record low radioactivity level, many orders of magnitude below surrounding materials on Earth. With a total mass of about 3200 kg, XENON1T is at the same time the largest detector of this type ever built. The combination of significantly increased size with much lower background implies an excellent discovery potential in the years to come.

    The XENON Collaboration consists of 135 researchers from the US, Germany, Italy, Switzerland, Portugal, France, the Netherlands, Israel, Sweden and the United Arab Emirates. The latest detector of the XENON family has been in science operation at the LNGS underground laboratory since autumn 2016. The only things you see when visiting the underground experimental site now are a gigantic cylindrical metal tank, filled with ultra-pure water to shield the detector at his center, and a three-story-tall, transparent building crowded with equipment to keep the detector running, with physicists from all over the world. The XENON1T central detector, a so-called Liquid Xenon Time Projection Chamber (LXeTPC), is not visible. It sits within a cryostat in the middle of the water tank, fully submersed, in order to shield it as much as possible from natural radioactivity in the cavern. The cryostat allows keeping the xenon at a temperature of -95°C without freezing the surrounding water.

    The mountain above the laboratory further shields the detector, preventing it to be perturbed by cosmic rays. But shielding from the outer world is not enough since all materials on Earth contain tiny traces of natural radioactivity. Thus extreme care was taken to find, select and process the materials making up the detector to achieve the lowest possible radioactive content. Laura Baudis, professor at the University of Zürich and professor Manfred Lindner from the Max-Planck-Institute for Nuclear Physics in Heidelberg emphasize that this allowed XENON1T to achieve record “silence”, which is necessary to listen with a larger detector much better for the very weak voice of dark matter.

    A particle interaction in liquid xenon leads to tiny flashes of light. This is what the XENON scientists are recording and studying to infer the position and the energy of the interacting particle and whether it might be dark matter or not. The spatial information allows to select interactions occurring in the central 1 ton core of the detector. The surrounding xenon further shields the core xenon target from all materials which already have tiny surviving radioactive contaminants. Despite the shortness of the 30-day science run the sensitivity of XENON1T has already overcome that of any other experiment in the field, probing un-explored dark matter territory.

    “WIMPs did not show up in this first search with XENON1T, but we also did not expect them so soon!” says Elena Aprile, Professor at Columbia University and spokesperson of the project. “The best news is that the experiment continues to accumulate excellent data which will allow us to test quite soon the WIMP hypothesis in a region of mass and cross-section with normal atoms as never before. A new phase in the race to detect dark matter with ultra-low background massive detectors on Earth has just began with XENON1T. We are proud to be at the forefront of the race with this amazing detector, the first of its kind.”

    Further information:
    http://www.xenon1t.org
    http://www.lngs.infn.it

    See the full article here .

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  • richardmitnick 5:39 pm on May 21, 2017 Permalink | Reply
    Tags: , , First evidence for the existence of the bottom quark, , , , Physics   

    From FNAL: “50 years of discoveries and innovations: Fermilab discovers bottom quark” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    May 21, 2017 [Working on Sunday. Me too. Science takes no days off.]
    Troy Rummler

    This year Fermilab celebrates a half-century of groundbreaking accomplishments. In recognition of the lab’s 50th birthday, we will post (in no particular order) a different innovation or discovery from Fermilab’s history every day between April 27 and June 15, the date in 1967 that the lab’s employees first came to work.

    The list covers important particle physics measurements, advances in accelerator science, astrophysics discoveries, theoretical physics papers, game-changing computing developments and more. While the list of 50 showcases only a small fraction of the lab’s impressive resume, it nevertheless captures the breadth of the lab’s work over the decades, and it reminds us of the remarkable feats of ingenuity, engineering and technology we are capable of when we work together to do great science.

    25. Fermilab discovers bottom quark

    3
    Dr. Leon Lederman

    In 1977, an experiment led by physicist and Nobel laureate Leon Lederman at Fermilab provided the first evidence for the existence of the bottom quark. It was observed as part of a quark-antiquark pair known as the Upsilon meson, which is 10 times more massive than a proton. The bottom quark is one of six that make up the quark family of particles.

    4

    See the full article here .

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    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), 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.

     
  • richardmitnick 3:32 pm on May 20, 2017 Permalink | Reply
    Tags: , , , , Biology [et al] needs more staff scientists, , , Physics   

    From Nature: “Biology needs more staff scientists” 

    Nature Mag
    Nature

    16 May 2017
    Steven Hyman

    Independent professionals advance science in ways faculty-run labs cannot, and such positions keep talented people in research, argues Steven Hyman.

    1
    Staff scientist Stacey Gabriel co-authored 25 of the most highly cited papers worldwide in 2015. Maria Nemchuk/Broad Inst.

    [I have to ask, I do a Women in STEM series, why are the women I see always so good looking. This cannot be normal. No uglies, no fatties, that just does not compute.]

    Most research institutions are essentially collections of independent laboratories, each run by principal investigators who head a team of trainees. This scheme has ancient roots and a track record of success. But it is not the only way to do science. Indeed, for much of modern biomedical research, the traditional organization has become limiting.

    A different model is thriving at the Broad Institute of MIT and Harvard in Cambridge, Massachusetts, where I work.


    Broad Institute Campus

    In the 1990s, the Whitehead Institute for Biomedical Research, a self-governing organization in Cambridge affiliated with the Massachusetts Institute of Technology (MIT), became the academic leader in the Human Genome Project. This meant inventing and applying methods to generate highly accurate DNA sequences, characterize errors precisely and analyse the outpouring of data. These project types do not fit neatly into individual doctoral theses. Hence, the institute created a central role for staff scientists — individuals charged with accomplishing large, creative and ambitious projects, including inventing the means to do so. These non-faculty scientists work alongside faculty members and their teams in collaborative groups.

    When leaders from the Whitehead helped to launch the Broad Institute in 2004, they continued this model. Today, our work at the Broad would be unthinkable without professional staff scientists — biologists, chemists, data scientists, statisticians and engineers. These researchers are not pursuing a tenured academic post and do not supervise graduate students, but do cooperate on and lead projects that could not be accomplished by a single academic laboratory.

    Physics long ago saw the need to expand into different organizational models. The Manhattan Project, which during the Second World War harnessed nuclear energy for the atomic bomb, was not powered by graduate students. Europe’s particle-physics laboratory, CERN, does not operate as atomized labs with each investigator pursuing his or her own questions.

    LHC

    CERN/LHC Map

    CERN LHC Tunnel

    CERN LHC particles

    And the Jet Propulsion Laboratory at the California Institute of Technology in Pasadena relies on professional scientists to get spacecraft to Mars.


    NASA JPL-Caltech Campus

    A different tack

    In biology, many institutes in addition to the Broad are experimenting with new organizational principles. The Mechanobiology Institute in Singapore pushes its scientists to use tools from other disciplines by discouraging individual laboratories from owning expensive equipment unless it is shared by all. The Howard Hughes Medical Institute’s Janelia Research Campus in Ashburn, Virginia, the Salk Institute of Biological Sciences in La Jolla, California, and the Allen Institute for Brain Science in Seattle, Washington, effectively mix the work of faculty members and staff scientists. Disease-advocacy organizations, such as the ALS Therapy Development Institute in Cambridge, do their own research without any faculty members at all.

    Each of these institutes has a unique mandate, and many are fortunate in having deep resources. They also had to be willing to break with tradition and overcome cultural barriers.

    At famed research facilities of yore, such as Bell Labs and IBM Laboratories, the title ‘staff scientist’ was a badge of honour. Yet to some biologists the term suggests a permanent postdoc or senior technician — someone with no opportunities for advancement who works solely in a supervisor’s laboratory, or who runs a core facility providing straightforward services. That characterization sells short the potential of professional scientists.

    The approximately 430 staff scientists at the Broad Institute develop cutting-edge computational methods, invent and incorporate new processes into research pipelines and pilot and optimize methodologies. They also transform initial hits from drug screens into promising chemical compounds and advance techniques to analyse huge data sets. In summary, they chart the path to answering complex scientific questions.

    Although the work of staff scientists at the Broad Institute is sometimes covered by charging fees to its other labs, our faculty members would never just drop samples off with a billing code and wait for data to be delivered. Instead, they sit down with staff scientists to discuss whether there is an interesting collaboration to be had and to seek advice on project design. Indeed, staff scientists often initiate collaborations.

    Naturally, tensions still arise. They can play out in many ways, from concerns over how fees are structured, to questions about authorship. Resolving these requires effort, and it is a task that will never definitively be finished.

    In my view, however, the staff-scientist model is a win for all involved. Complex scientific projects advance more surely and swiftly, and faculty members can address questions that would otherwise be out of reach. This model empowers non-faculty scientists to make independent, creative contributions, such as pioneering new algorithms or advancing technologies. There is still much to do, however. We are working to ensure that staff scientists can continue to advance their careers, mentor others and help to guide the scientific direction of the institute.

    As the traditional barriers break down, science benefits. Technologies that originate in a faculty member’s lab sometimes attract more collaborations than one laboratory could sustain. Platforms run by staff scientists can incorporate, disseminate and advance these technologies to capture more of their potential. For example, the Broad Institute’s Genetic Perturbation Platform, run by physical chemist David Root, has honed high-throughput methods for RNA interference and CRISPR screens so that they can be used across the genome in diverse biological contexts. Staff scientists make the faculty more productive through expert support, creativity, added capacity and even mentoring in such matters as the best use of new technologies. The reverse is also true: faculty members help staff scientists to gain impact.

    Our staff scientists regularly win scientific prizes and are invited to give keynote lectures. They apply for grants as both collaborators and independent investigators, and publish regularly. Since 2011, staff scientists have led 36% of all the federal grants awarded for research projects at the Broad Institute (see ‘Staff-led grants’). One of our staff scientists, genomicist Stacey Gabriel, topped Thomson Reuters’ citation analysis of the World’s Most Influential Scientific Minds in 2016. She co-authored 25 of the most highly cited papers in 2015 — a fact that illustrates both how collaborative the Broad is and how central genome-analysis technologies are to answering key biological questions.

    3
    Source: Broad Inst.

    At the Broad Institute’s Stanley Center for Psychiatric Research, which I direct, staff scientists built and operate HAIL, a powerful open-source tool for analysis of massive genetics data sets. By decreasing computational time, HAIL has made many tasks 10 times faster, and some 100 times faster. Staff scientist Joshua Levin has developed and perfected RNA-sequencing methods used by many colleagues to analyse models of autism spectrum disorders and much else. Nick Patterson, a mathematician and computational biologist at the Stanley Center, began his career by cracking codes for the British government during the cold war. Today, he uses DNA to trace past migrations of entire civilizations, helps to solve difficult computational problems and is a highly valued support for many biologists.

    Irrational resistance

    Why haven’t more research institutions expanded the roles of staff scientists? One reason is that they can be hard to pay for, especially by conventional means. Some funding agencies look askance at supporting this class of professionals; after all, graduate students and postdocs are paid much less. In my years leading the US National Institute of Mental Health, I encountered people in funding bodies across the world who saw a rising ratio of staff to faculty members or of staff to students as evidence of fat in the system.

    That said, there are signs of flexibility. In 2015, the US National Cancer Institute began awarding ‘research specialist’ grants — a limited, tentative effort designed in part to provide opportunities for staff scientists. Sceptical funders should remember that trainees often take years to become productive. More importantly, institutions’ misuse of graduates and postdocs as cheap labour is coming under increasing criticism (see, for example, B. Alberts et al. Proc. Natl Acad. Sci. USA 111, 5773–5777; 2014).

    Faculty resistance is also a factor. I served as Harvard University’s provost (or chief academic officer) for a decade. Several years in, I launched discussions aimed at expanding roles for staff scientists. Several faculty members worried openly about competition for space and other scarce resources, especially if staff scientists were awarded grants but had no teaching responsibilities. Many recoiled from any trappings of corporatism or from changes that felt like an encroachment on their decision-making. Some were explicitly concerned about a loss of access and control, and were not aware of the degree to which staff scientists’ technological expertise and cross-disciplinary training could help to answer their research questions.

    Institutional leaders can mitigate these concerns by ensuring that staff positions match the shared goals of the faculty — for scientific output, education and training. They must explain how staff-scientist positions create synergies rather than silos. Above all, hiring plans must be developed collaboratively with faculty members, not by administrators alone.

    The Broad Institute attracts world-class scientists, as both faculty members and staff. Its appeal has much to do with how staff scientists enable access to advanced technology, and a collaborative culture that makes possible large-scale projects rarely found in academia. The Broad is unusual — all faculty members also have appointments at Harvard University, MIT or Harvard-affiliated hospitals. The institute has also benefited from generous philanthropy from individuals and foundations that share our values and believe in our scientific mission.

    Although traditional academic labs have been and continue to be very productive, research institutions should look critically and creatively at their staffing. Creating a structure like that of the Broad Institute would be challenging in a conventional university. Still, I believe any institution that is near an academic health centre or that has significant needs for advanced technology could benefit from and sustain the careers of staff scientists. If adopted judiciously, these positions would enable institutions to take on projects of unprecedented scope and scale. It would also create a much-needed set of highly rewarding jobs for the rising crop of talented researchers, particularly people who love science and technology but who do not want to pursue increasingly scarce faculty positions.

    A scientific organization should be moulded to the needs of science, rather than constrained by organizational traditions.

    See the full article here .

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 1:54 pm on May 19, 2017 Permalink | Reply
    Tags: A new atom beam machine being installed at SUNY Poly in Albany for use in computer chip manufacturing., , , Physics, , TimesUnion   

    From SUNY Poly via TimesUnion: “Chip equipment startup at SUNY Poly gains traction” 

    suny-poly-bloc

    SUNY Polytechnic Institute

    1

    TimesUnion

    May 19, 2017
    Larry Rulison

    2
    Photo: Neutral Physics Corp.

    A new atom beam machine being installed at SUNY Poly in Albany for use in computer chip manufacturing.

    A semiconductor manufacturing startup based at SUNY Polytechnic Institute in Albany is thriving despite all of the upheaval lately at the school.

    Neutral Physics Corp., a joint venture between Exogenesis Corp. and Sematech, the computer chip manufacturing consortium based at SUNY Poly, had its new atom beam “tool” delivered to one of SUNY Poly’s chip manufacturing clean rooms just this week to begin “alpha” testing.

    Exogenesis, which is based outside Boston, announced the novel technology development venture with Sematech back in 2015, although it has received little attention since.

    Both Exogenesis and Sematech are shareholders in the company, which is making an atomic particle accelerator that produces atomic-scale etchings onto the silicon wafers used to make computer chips.

    Although Sematech recently dismissed its CEO and has scaled back its operations in recent years, Exogenesis CEO Richard Svrluga told the Times Union that his company’s partnership with Sematech and SUNY Poly has been extremely beneficial.

    The startup just named a new CEO this month – former IBM executive R. “Jaga” Jagannathan – and recent had a “successful” round of Series A financing from outside investors, Svrluga said.

    “Jaga has extensive experience in the semiconductor industry with much of that experience from his years at IBM,” Svrluga said.

    The startup is also being aided by Sematech and Exogenesis executives who have been appointed to leadership roles.

    Sematech has operated as a technology development consortium for the chip industry for most of its history dating back to the 1980s.

    It hasn’t actually started new companies in the past, although the creation of tech startups is part of the mission of SUNY Poly, which moved Sematech to Albany from Austin, Texas about 10 years ago.

    “Our goal is to build a successful business that will in turn generate good jobs for the region,” Svrluga said. “In general, we are feeling extremely positive about where (Neutral Physics Corp.) is at this point of its development. We also very much appreciate the support that we have always received from the staff at Sematech.”

    See the full article here .

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    suny-poly-campus

    The State University of New York Polytechnic Institute, commonly referred to as SUNY Polytechnic Institute or SUNY Poly, is a public research university with campuses in the town of Marcy in the Utica-Rome metropolitan area and Albany, New York. Founded in 1966 using classrooms at a primary school, SUNY Poly is New York’s public polytechnic college. The Marcy campus, formerly the SUNY Institute of Technology, has a Utica, New York mailing address and was established in 1987. The Albany campus was formerly a component of the University at Albany, established in January 2003.

    SUNY Poly is accredited by the Middle States Association of Colleges and Schools. The university offers over 30 bachelor’s degrees, 15 master’s degrees, and three doctoral degrees within five different colleges. SUNY Poly students come from across the state of New York, throughout the United States, and more than twenty other nations. More than 25,000 alumni enjoy successful careers in a wide range of fields.

     
  • richardmitnick 12:49 pm on May 19, 2017 Permalink | Reply
    Tags: , , , , ESA/Lisa, GEO600, , Physics,   

    From Science Alert: “Einstein’s ‘Spooky’ Entanglement Is Guiding Next-Gen Gravitational Wave Detectors” 

    ScienceAlert

    Science Alert

    19 MAY 2017
    DAVID BLAIR

    1
    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger-Zib

    Breaking the standard quantum limit.

    The first direct detection of gravitational waves, a phenomenon predicted by Einstein’s 1915 general theory of relativity, was reported by scientists in 2016.

    Armed with this “discovery of the century”, physicists around the world have been planning new and better detectors of gravitational waves.


    Caltech/MIT Advanced aLigo Hanford, WA, USA installation


    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project


    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger-Zib

    ESA/eLISA the future of gravitational wave research

    Physicist Professor Chunnong Zhao and his recent PhD students Haixing Miao and Yiqiu Ma are members of an international team that has created a particularly exciting new design for gravitational wave detectors.

    The new design is a real breakthrough because it can measure signals below a limit that was previously believed to be an insurmountable barrier. Physicists call this limit the standard quantum limit. It is set by the quantum uncertainty principle.

    Proposal for gravitational-wave detection beyond the standard quantum limit through EPR entanglement
    Yiqiu Ma, Haixing Miao, Belinda Heyun Pang, Matthew Evans, Chunnong Zhao, Jan Harms, Roman Schnabel & Yanbei Chen

    The new design, published in Nature Physics this week, shows that this may not be a barrier any longer.

    Abstract

    In continuously monitored systems the standard quantum limit is given by the trade-off between shot noise and back-action noise. In gravitational-wave detectors, such as Advanced LIGO, both contributions can be simultaneously squeezed in a broad frequency band by injecting a spectrum of squeezed vacuum states with a frequency-dependent squeeze angle. This approach requires setting up an additional long baseline, low-loss filter cavity in a vacuum system at the detector’s site. Here, we show that the need for such a filter cavity can be eliminated, by exploiting Einstein–Podolsky–Rosen (EPR)-entangled signals and idler beams. By harnessing their mutual quantum correlations and the difference in the way each beam propagates in the interferometer, we can engineer the input signal beam to have the appropriate frequency-dependent conditional squeezing once the out-going idler beam is detected. Our proposal is appropriate for all future gravitational-wave detectors for achieving sensitivities beyond the standard quantum limit.
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    Figure 1
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    figure 2
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    Figure 3
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    Figure 4
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    Figure 5

    Using this and other new approaches may allow scientists to monitor black hole collisions and ‘spacequakes‘ across the whole of the visible Universe.

    4
    During a spacequake, Earth’s magnetic field shakes in a way that is analogous to the shaking of the ground during an earthquake. Image credit: Evgeny Panov, Space Research Institute of Austria.

    How gravitational wave detectors work

    Gravitational waves are not vibrations travelling through space, but rather vibrations of space itself.

    They have already told us about an unexpectedly large population of black holes. We hope that further study of gravitational waves will help us to better understand our Universe.

    But the technologies of gravitational wave detectors are likely to have enormous significance beyond this aspect of science, because in themselves they are teaching us how to measure unbelievably tiny amounts of energy.

    Gravitational wave detectors use laser light to pick up tiny vibrations of space created when black holes collide. The collisions create vast gravitational explosions.

    They are the biggest explosions known in the Universe, converting mass directly into vibrations of pure space.

    It takes huge amounts of energy to make space bend and ripple.

    Our detectors – exquisitely perfect devices that use big heavy mirrors with scarily powerful lasers – must measure space stretching by a mere billionth of a billionth of a metre over the four kilometre scale of our detectors. [LIGO, above.]

    These measurements already represent the smallest amount of energy ever measured.

    But for gravitational wave astronomers this is not good enough. They need even more sensitivity to be able to hear many more predicted gravitational ‘sounds’, including the sound of the moment the Universe was created in the big bang.

    This is where the new design comes in.

    A spooky idea from Einstein

    The novel concept is founded on original work from Albert Einstein.

    In 1935 Albert Einstein and co-workers Boris Podolsky and Nathan Rosen tried to depose the theory of quantum mechanics by showing that it predicted absurd correlations between widely spaced particles.

    Einstein proved that if quantum theory was correct, then pairs of widely spaced objects could be entangled like two flies tangled up in a spider’s web. Weirdly, the entanglement did not diminish, however far apart you allowed the objects to move.

    Einstein called entanglement “spooky action at a distance”. He was sure that his discovery would do away with the theory of quantum mechanics once and for all, but this was not to be.

    Since the 1980s physicists have demonstrated time and again that quantum entanglement is real. However much he hated it, Einstein’s prediction was right and to his chagrin, quantum theory was correct. Things at a distance could be entangled.

    Today physicists have got used to the ‘spookiness’, and the theory of entanglement has been harnessed for the sending of secret codes that cannot be intercepted.

    Around the world, organisations such as Google and IBM and academic laboratories are trying to create quantum computers that depend on entanglement.

    And now Zhao and colleagues want to use the concept of entanglement to create the new gravitational wave detector’s design.

    A new way to measure gravitational waves

    The exciting aspect of the new detector design is that it is actually just a new way of operating existing detectors. It simply uses the detector twice.

    One time, photons in the detector are altered by the gravitational wave so as to pick up the waves. The second time, the detector is used to change the quantum entanglement in such a way that the noise due to quantum uncertainty is not detected.

    The only thing that is detected is the motion of the distant mirrors caused by the gravitational wave. The quantum noise from the uncertainty principle does not appear in the measurement.

    To make it work, you have to start with entangled photons that are created by a device called a quantum squeezer. This technology was pioneered for gravitational wave astronomy at Australian National University, and is now an established technique.

    Like many of the best ideas, the new idea is a very simple one, but one that took enormous insight to recognise. You inject a minuscule amount of squeezed light from a quantum squeezer, and use it twice!

    Around the world physicists are getting ready to test the new theory and find the best way of implementing it in their detectors.

    One of these is the GEO gravitational wave detector at Hannover in Germany, which has been a test bed for many of the new technologies that allowed last year’s momentous discovery of gravitational waves.

    6
    http://www.geo600.org GEO600 aims at the direct detection of Einstein’s gravitational waves by means of a laser interferometer.

    See the full article here .

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  • richardmitnick 11:26 am on May 17, 2017 Permalink | Reply
    Tags: , , , , , , , Maura McLaughlin, , Physics, ,   

    From Physics: Women in STEM – “Q and A: Catching a Gravitational Wave with a Pulsar’s Beam” Maura McLaughlin 

    Physics LogoAbout Physics

    Physics Logo 2

    Physics

    May 12, 2017
    Katherine Wright

    Maura McLaughlin explains how the electromagnetic signals from fast-spinning neutron stars could be used to detect gravitational waves.

    1
    Maura McLaughlin. Greg Ellis/West Virginia University

    Pulsars captivate Maura McLaughlin, a professor at West Virginia University. These highly magnetized neutron stars flash beams of electromagnetic radiation as they spin. And with masses equivalent to that of the Sun, but diameters seventy thousand times smaller, they are—besides black holes—the densest objects in the Universe. Astrophysicists still have many questions about pulsars, ranging from how they emit electromagnetic radiation to why they are so incredibly dense. But it’s exploiting the highly stable, periodic electromagnetic signals of pulsars to study gravitational waves that currently has McLaughlin hooked. In an interview with Physics, she explained where her fascination with pulsars came from, what gravitational-wave sources she hopes to detect, and why she recently visited Washington, D.C., to talk with members of Congress.

    With the 2015 detection of gravitational waves, it’s obviously an exciting time to work in astrophysics. But what initially drew you to the field and to pulsars?

    The astrophysicist Alex Wolszczan. I met him in the early 90s while I was an undergrad at Penn State, and just after he had discovered the first extrasolar planets. These planets were orbiting a pulsar—lots of people don’t know that. I found this pulsar system fascinating and ended up working with Wolszczan one summer as a research assistant. I got to go to Puerto Rico to observe pulsars at the Arecibo Observatory, which is the biggest telescope in the world. The experience was really cool.
    How do researchers detect gravitational waves with pulsars?

    The collaboration that I’m part of—NANOGrav—is searching for changes in the travel time of the pulsar’s radio emission due to the passing of gravitational waves.

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    NANOGrave Gravitational waves JPL-Caltech David Champion

    When a gravitational wave passes between us and the pulsar, it stretches and squeezes spacetime, causing the pulse to arrive a bit earlier or later than it would in the absence of the wave. We time the arrival of pulsar signals for years to try to detect these small changes.
    What gravitational-wave-producing events do you expect to detect with pulsars? Could you see the same events as LIGO did?

    LIGO is sensitive to very short time-scale gravitational waves, on the order of milliseconds to seconds, while our experiment is sensitive to very long time-scale gravitational waves, on the order of years. We could never detect gravitational waves from two stellar-mass black holes merging—the time scale of the event is just too short. But we will be able to detect waves from black hole binaries in their inspiralling stage, when they’re still orbiting each other with periods of years. Also, our approach can only detect black holes that are much more massive that those LIGO observed. Our primary targets are supermassive black holes, even more massive than the one at the core of the Milky Way.


    Caltech/MIT Advanced aLigo Hanford, WA, USA installation


    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project


    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger-Zib

    ESA/eLISA the future of gravitational wave research

    LIGO is basically probing the evolution and end products of stars, whereas our experiment is probing the evolution of galaxies and the cosmos. We’ll be able to look way back in time at the processes by which galaxies formed through mergers.
    The first detection of gravitational waves was front-page news. What impact has it had on your research?

    I, and others in NANOGrav, got lots of condolences after LIGO’s detection, like “oh we’re sorry you weren’t first.” But it’s been good for us. It has really spurred us on to make a detection. And it has made us more optimistic—if it worked for LIGO it should work for us, as our methods are rooted in the same principles. None of us doubted gravitational waves existed, but as far as funding agencies and the public go, LIGO’s detection makes a big difference. Now people can’t say, “Who knows if these things exist?” or “Who knows if these methods work?” LIGO’s detection has shown they do exist and the methods do work.

    Apart from doubters, what other challenges do you face with your pulsar experiment?

    Right now, our most significant challenge is that our radio telescopes are in danger of being shut down. Both Arecibo and the Green Bank Telescope (GBT) in West Virginia are suffering significant funding cuts.

    NAIC/Arecibo Observatory, Puerto Rico, USA



    GBO radio telescope, Green Bank, West Virginia, USA

    Many of our NANOGrav discussions lately are about what we can do to retain access to these telescopes. Losing one of these telescopes would reduce our experiment’s sensitivity by roughly half and increase the time to detection by at least several years. If we lose both, our project is dead in the water. Arecibo and GBT are currently the two most sensitive radio telescopes in the world . I think its crazy that they are possibly being shut down.

    [Do not forget FAST-China]

    FAST radio telescope, now operating, located in the Dawodang depression in Pingtang county Guizhou Province, South China

    What are you doing to address the problem?

    I recently spent two days on Capitol Hill in Washington, D.C., talking to senators and House representatives trying to make the case to keep GBT open. Most of the politicians actually agreed it should stay open; it’s just a matter of funding. Science in general just doesn’t have enough funding.

    How do you frame the issues when talking to politicians about science?

    I try really hard to stress the opportunities for training students, the infrastructure, and the number of people who work at these telescopes. The technologies developed at the facilities are cutting edge and can be used for more than studying space. The science is incredibly interesting, but that in itself doesn’t always appeal to everybody.

    With the current administration, arguments of US prominence are also really valuable. China [has built ans is operating] a bigger telescope than Arecibo, and soon we won’t have the largest radio telescope in the world. Right now we are world leaders, but if the US wants to keeps its dominance then these telescopes have to remain open.

    With the challenges you face, what would you say to someone thinking of joining this field?

    Despite uncertainties with the telescopes, the future is bright. Now is a really good time to join the field: we’re going to make a detection any day now.

    See the full article here .

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    Physicists are drowning in a flood of research papers in their own fields and coping with an even larger deluge in other areas of physics. How can an active researcher stay informed about the most important developments in physics? Physics highlights a selection of papers from the Physical Review journals. In consultation with expert scientists, the editors choose these papers for their importance and/or intrinsic interest. To highlight these papers, Physics features three kinds of articles: Viewpoints are commentaries written by active researchers, who are asked to explain the results to physicists in other subfields. Focus stories are written by professional science writers in a journalistic style and are intended to be accessible to students and non-experts. Synopses are brief editor-written summaries. Physics provides a much-needed guide to the best in physics, and we welcome your comments (physics@aps.org).

     
  • richardmitnick 8:58 pm on May 16, 2017 Permalink | Reply
    Tags: , Alastair Paragas, , , , , , , Physics   

    From FIU: “My Internship with CERN” Alastair Paragas 

    FIU bloc

    This post is dedicated to J.L.T. who will prove Loop Quantum Gravity. I hope he sees it.

    Florida International University

    05/15/2017
    Millie Acebal

    1
    Name: Alastair Paragas

    Major: Computer Science (College of Engineering and Computing and Honors College)

    Hometown: Originally from Manila, Philippines; currently living in Homestead, Florida

    Where will you intern ? Starting June 19, I will intern at CERN, located in Geneva, Switzerland. CERN is the home of the (Large) (H)adron (C)ollider where the Higgs-Boson particle was discovered.

    LHC

    CERN/LHC Map

    CERN LHC Tunnel

    CERN LHC particles

    2
    Tim Berners-Lee
    https://www.w3.org/People/Berners-Lee/

    Another great development at CERN was the creation of the modern internet – the (W)orld (W)ide (W)eb, with web pages as accessible documents through HTTP (HyperText Transfer Protocol), as developed by Tim Berners-Lee.

    Though CERN is in Geneva, I will be living in Saint Genis-Pouilly, France. Saint Genis-Pouilly is a town on the French side of the Franco-Swiss border, with CERN being on the Swiss side of the border. Luckily enough, the commute is only 2 miles long and is quite permissive because of the relaxed borders between the two countries due mostly in part to CERN’s importance to the European Union as a nuclear research facility. As such, I get to cross the border twice a day!

    What do you do there?

    I will be doing research and actual software engineering work with CERN’s distributed computing and data reporting/analytics team, under the mentorship of Manuel Martin Marquez. I will ensure the software that transports real-time data collected from the various instrumentation and devices at CERN don’t get lost! I also get to develop software that stores such data into both online transactional and analytical processing workloads.

    How did you get your internship?

    Out of 1,560 complete applications (and more partial applications), I was happy to be chosen as one of three other U.S. students, and in total 33 other students around the world.

    I was also lucky to also be accepted as an intern at NASA’s Langley Research Center (Virginia), under their autonomous algorithm team and the mentorship of A.J. Narkawicz, working on the DAEDALUS and ICAROUS projects for autonomous unmanned aerial and watercraft systems. Most of this software supports and runs with/on critical software that operate in all of modern American airports and air traffic control. However, I chose to turn this down for CERN.

    How does your internship connect back to your coursework?

    The internship connects back to what I learned in Operating Systems, Database and Survey of Database Systems; I learned to work with managing synchronization between concurrent processes as well as lower-level software aspects of a computer; how to manage data across various data stores; get an idea of the importance of various features of a relational database; and when not to use a relational database (of which are very few and far-in-between) and so forth.

    What about this internship opportunity excites you the most?

    I am looking forward to living in Europe, completely free, for nine weeks! I never thought it would be possible for me to travel around the world in such a capacity – and for that, I am very grateful.

    Coming from a poor background as an immigrant, I would never think it possible to be a citizen of the United States, much less, be able to do things like this.

    What have you learned about yourself?

    I learned that just like always, I am cheap and would like to live on the bare minimum. Even in my previous internships, I remember calculating my grocery costs to ensure that they were optimal and that I wasn’t breaking the budget, even if I can afford the cost and I am already starting to suffer looking around at food prices at local stores in the area.

    How will this internship help you professionally?

    I expect that just like my internships at Wolfram and Apple, I can network with highly intelligent people coming from diverse fields of study, ranging from physics, mathematics, mechanical engineering and computer science. I am always humbled working with behemoths from their respective fields, living and working on the shoulders of giants.

    What advice do you have for others starting the internship process?

    This is my third internship. I interned at Wolfram during my sophomore year in Waltham, MA, building a research project utilizing Wolfram technologies. I also completed an internship at Apple during my junior year as a software engineer in Cupertino, CA, building real-time streaming and batch data processing and reporting softwares in Apple’s Internet Software and Services Department.

    At our club – Association for Computing Machinery at FIU – we’ve also managed to create a community of highly successful and motivated students doing internships this summer at prestigious companies (all software engineering roles at companies like Chase, State Farm, Target, MathWorks and etc). We have weekly workshops on machine learning, big data, web/mobile application development, programming languages and a lot of other real-world engineering principles that escape the more academic theory of the computer science/information technology curriculum.

    We also get tons of our members to come to hackathons with us, whether by getting their travel expenses reimbursed or carpools! Considering that we are club officers, we don’t get paid for the services we do for the club – we’re seriously and passionately committed and do care about getting as many students into the level of expertise and careers they want for themselves.

    Anything else you’d care to share?

    On a more personal note, I would also like to say that just like everyone else, I have had bouts in my life where I felt like I was not accomplishing anything and also suffered from the emotions that come with that. It is important to never place someone on a pedestal while seeing yourself as little. However hard those moments may hit, I consider it highly important to re-evaluate and to emphasize to yourself the importance of working harder and fighting against possible temptations and vices that may result from such emotions and impulses; the idea of not giving up is all the more important.

    Personally, I was able to fight through this by being a part of my local Marine Corps’ DEP (Delayed Entry Program) program, under the mentorship of Sgt. Ariel Tavarez, where I was able to reflect, get inspired and work through grueling physical exercises with people who have made an impactful change in their lives. Different solutions work for different people, but the one thing that stays true across all these, is to always stay your course.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    FIU Campus

    As Miami’s first and only public research university, offering bachelor’s, master’s, and doctoral degrees, FIU is worlds ahead in its service to the academic and local community.

    Designated as a top-tier research institution, FIU emphasizes research as a major component in the university’s mission. The Herbert Wertheim College of Medicine and the School of Computing and Information Sciences’ Discovery Lab, are just two of many colleges, schools, and centers that actively enhance the university’s ability to set new standards through research initiatives.

     
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