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  • richardmitnick 9:16 am on August 21, 2018 Permalink | Reply
    Tags: , Building phylogenetic trees, Chronograms, , , Geobiology, , Investigating Earth’s earliest life, Kelsey Moore, , ,   

    From MIT News: Women in STEM- “Investigating Earth’s earliest life” Kelsey Moore 

    MIT News
    MIT Widget

    From MIT News

    August 18, 2018
    Fatima Husain

    1
    Kelsey Moore. Image: Ian MacLellan

    Graduate student Kelsey Moore uses genetic and fossil evidence to study the first stages of evolution on our planet.

    In the second grade, Kelsey Moore became acquainted with geologic time. Her teachers instructed the class to unroll a giant strip of felt down a long hallway in the school. Most of the felt was solid black, but at the very end, the students caught a glimpse of red.

    That tiny red strip represented the time on Earth in which humans have lived, the teachers said. The lesson sparked Moore’s curiosity. What happened on Earth before there were humans? How could she find out?

    A little over a decade later, Moore enrolled in her first geoscience class at Smith College and discovered she now had the tools to begin to answer those very questions.

    Moore zeroed in on geobiology, the study of how the physical Earth and biosphere interact. During the first semester of her sophomore year of college, she took a class that she says “totally blew my mind.”

    “I knew I wanted to learn about Earth history. But then I took this invertebrate paleontology class and realized how much we can learn about life and how life has evolved,” Moore says. A few lectures into the semester, she mustered the courage to ask her professor, Sara Pruss in Smith’s Department of Geosciences, for a research position in the lab.

    Now a fourth-year graduate student at MIT, Moore works in the geobiology lab of Associate Professor Tanja Bosak in MIT’s Department of Earth, Atmospheric, and Planetary Sciences. In addition to carrying out her own research, Moore, who is also a Graduate Resident Tutor in the Simmons Hall undergraduate dorm, makes it a priority to help guide the lab’s undergraduate researchers and teach them the techniques they need to know.

    Time travel

    “We have a natural curiosity about how we got here, and how the Earth became what it is. There’s so much unknown about the early biosphere on Earth when you go back 2 billion, 3 billion, 4 billion years,” Moore says.

    Moore studies early life on Earth by focusing on ancient microbes from the Proterozoic, the period of Earth’s history that spans 2.5 billion to 542 million years ago — between the time when oxygen began to appear in the atmosphere up until the advent and proliferation of complex life. Early in her graduate studies, Moore and Bosak collaborated with Greg Fournier, the Cecil and Ida Green Assistant Professor of Geobiology, on research tracking cyanobacterial evolution. Their research is supported by the Simons Collaboration on the Origins of Life.

    An image of Cyanobacteria, Tolypothrix

    The question of when cyanobacteria gained the ability to perform oxygenic photosynthesis, which produces oxygen and is how many plants on Earth today get their energy, is still under debate. To track cyanobacterial evolution, MIT researchers draw from genetics and micropaleontology. Moore works on molecular clock models, which track genetic mutations over time to measure evolutionary divergence in organisms.

    Clad with a white lab coat, lab glasses, and bright purple gloves, Moore sifts through multiple cyanobacteria under a microscope to find modern analogs to ancient cyanobacterial fossils. The process can be time-consuming.

    “I do a lot of microscopy,” Moore says with a laugh. Once she’s identified an analog, Moore cultures that particular type of cyanobacteria, a process which can sometimes take months. After the strain is enriched and cultured, Moore extracts DNA from the cyanobacteria. “We sequence modern organisms to get their genomes, reconstruct them, and build phylogenetic trees,” Moore says.

    By tying information together from ancient fossils and modern analogs using molecular clocks, Moore hopes to build a chronogram — a type of phylogenetic tree with a time component that eventually traces back to when cyanobacteria evolved the ability to split water and produce oxygen.

    Moore also studies the process of fossilization, on Earth and potentially other planets. She is collaborating with researchers at NASA’s Jet Propulsion Laboratory to help them prepare for the upcoming Mars 2020 rover mission.

    “We’re trying to analyze fossils on Earth to get an idea for how we’re going to look at whatever samples get brought back from Mars, and then to also understand how we can learn from other planets and potentially other life,” Moore says.

    After MIT, Moore hopes to continue research, pursue postdoctoral fellowships, and eventually teach.

    “I really love research. So why stop? I’m going to keep going,” Moore says. She says she wants to teach in an institution that emphasizes giving research opportunities to undergraduate students.

    “Undergrads can be overlooked, but they’re really intelligent people and they’re budding scientists,” Moore says. “So being able to foster that and to see them grow and trust that they are capable in doing research, I think, is my calling.”

    Geology up close

    To study ancient organisms and find fossils, Moore has traveled across the world, to Shark Bay in Australia, Death Valley in the United States, and Bermuda.

    “In order to understand the rocks, you really have to get your nose on the rocks. Go and look at them, and be there. You have to go and stand in the tidal pools and see what’s happening — watch the air bubbles from the cyanobacteria and see them make oxygen,” Moore says. “Those kinds of things are really important in order to understand and fully wrap your brain around how important those interactions are.”

    And in the field, Moore says, researchers have to “roll with the punches.”

    “You don’t have a nice, beautiful, pristine lab set up with all the tools and equipment that you need. You just can’t account for everything,” Moore says. “You have to do what you can with the tools that you have.”

    Mentorship

    As a Graduate Resident Tutor, Moore helps to create supporting living environments for the undergraduate residents of Simmons Hall.

    Each week, she hosts a study break in her apartment in Simmons for her cohort of students — complete with freshly baked treats. “[Baking] is really relaxing for me,” Moore says. “It’s therapeutic.”

    “I think part of the reason I love baking so much is that it’s my creative outlet,” she says. “I know that a lot of people describe baking as like chemistry. But I think you have the opportunity to be more creative and have more fun with it. The creative side of it is something that I love, that I crave outside of research.”

    Part of Moore’s determination to research, trek out in the field, and mentor undergraduates draws from her “biggest science inspiration” — her mother, Michele Moore, a physics professor at Spokane Falls Community College in Spokane, Washington.

    “She was a stay-at-home mom my entire childhood. And then when I was in middle school, she decided to go and get a college degree,” Moore says. When Moore started high school, her mother earned her bachelor’s degree in physics. Then, when Moore started college, her mother earned her PhD. “She was sort of one step ahead of me all the time, and she was a big inspiration for me and gave me the confidence to be a woman in science.”

    See the full article here .


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    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

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  • richardmitnick 7:21 am on August 21, 2018 Permalink | Reply
    Tags: , , , , , First Stars Formed No Later Than 250 Million Years After The Big Bang With Direct Proof   

    From Ethan Siegel: “First Stars Formed No Later Than 250 Million Years After The Big Bang, With Direct Proof” 

    From Ethan Siegel
    Aug 20, 2018

    1
    In the big image at left, the many galaxies of a massive cluster called MACS J1149+2223 dominate the scene. Gravitational lensing by the giant cluster brightened the light from the newfound galaxy, known as MACS 1149-JD, some 15 times. At upper right, a partial zoom-in shows MACS 1149-JD in more detail, and a deeper zoom appears to the lower right. This is correct and consistent with General Relativity, and independent of how we visualize (or whether we visualize) space. (NASA/ESA/STSCI/JHU)

    The Universe is an enormous place, but we can’t see all the way back to the beginning. Here’s the latest record-breaker.

    No matter how far back we look in the Universe, we cannot yet observe the first stars or galaxies directly.

    2
    The absorption lines at a variety of redshifts show that the fundamental physics and sizes of atoms have not changed throughout the Universe, even as the light has redshifted due to its expansion. Unfortunately, the most light-blocking material exists at the earliest times, making finding the most distant galaxies an incredible challenge. (NASA, ESA, AND AND A. FEILD (STSCI))

    NASA/ESA Hubble Telescope

    The light they produce is too redshifted and blocked by too much intervening gas to be seen even by Hubble.

    3
    The most distant galaxy ever discovered in the known Universe, GN-z11, has its light come to us from 13.4 billion years ago: when the Universe was only 3% its current age: 407 million years old. But there are even more distant galaxies out there, and we at last have direct evidence for it. (NASA, ESA, AND G. BACON (STSCI))

    The most distant galaxy ever discovered is already late, dating back to 407 million years after the Big Bang.

    4
    Only because this distant galaxy, GN-z11, is located in a region where the intergalactic medium is mostly reionized, can Hubble reveal it to us at the present time. To see further, we require a better observatory, optimized for these kinds of detection, than Hubble. (NASA, ESA, AND A. FEILD (STSCI))

    But the very first stars should go back hundreds of million years further.

    5
    Various long-exposure campaigns, like the Hubble eXtreme Deep Field (XDF) shown here, have revealed thousands of galaxies in a volume of the Universe that represents a fraction of a millionth of the sky. But even with all the power of Hubble, and all the magnification of gravitational lensing, there are still galaxies out there beyond what we are capable of seeing. (NASA, ESA, H. TEPLITZ AND M. RAFELSKI (IPAC/CALTECH), A. KOEKEMOER (STSCI), R. WINDHORST (ARIZONA STATE UNIVERSITY), AND Z. LEVAY (STSCI))

    Gravitational Lensing NASA/ESA

    Sometime between the Cosmic Microwave Background [CMB], at 380,000 years, and that first galaxy, the first stars must have formed.

    Cosmic Background Radiation per ESA/Planck


    ESA/Planck 2009 to 2013

    6
    Schematic diagram of the Universe’s history, highlighting reionization. Before stars or galaxies formed, the Universe was full of light-blocking, neutral atoms. While most of the Universe doesn’t become reionized until 550 million years afterwards, a few fortunate regions are mostly reionized at much earlier times. (S. G. DJORGOVSKI ET AL., CALTECH DIGITAL MEDIA CENTER)

    Owing to the second-most-distant galaxy ever found, MACS1149-JD1, we can understand when.

    7
    The distant galaxy MACS1149-JD1 is gravitationally lensed by a foreground cluster, allowing it to be imaged at high resolution and in multiple instruments, even without next-generation technology.(ALMA (ESO/NAOJ/NRAO), NASA/ESA HUBBLE SPACE TELESCOPE, W. ZHENG (JHU), M. POSTMAN (STSCI), THE CLASH TEAM, HASHIMOTO ET AL.)

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    We see MACS1149-JD1 as it was 530 million years after the Big Bang, while inside, it has a special signature: oxygen.

    8
    Supernova remnants (L) and planetary nebulae (R) are both ways for stars to recycle their burned, heavy elements back into the interstellar medium and the next generation of stars and planets. The truly first, pristine stars need to have been created before supernovae, planetary nebulae, or neutron star mergers polluted the interstellar medium with heavy elements. The detection of oxygen in this ultra-distant galaxy, along with the galaxy’s brightness, tells us it is already approximately 280 million years since the first stars formed within it.(ESO / VERY LARGE TELESCOPE / FORS INSTRUMENT & TEAM (L); NASA, ESA, C.R. O’DELL (VANDERBILT), AND D. THOMPSON (LARGE BINOCULAR TELESCOPE) (R))

    ESO VLT at Cerro Paranal in the Atacama Desert, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).
    elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo


    ESO/FORS1 on the VLT


    U Arizona Large Binocular Telescope, Large Binocular Telescope Interferometer, or LBTI, is a ground-based instrument connecting two 8-meter class telescopes on Mount Graham, Arizona, USA, Altitude 3,221 m (10,568 ft.) to form the largest single-mount telescope in the world. The interferometer is designed to detect and study stars and planets outside our solar system. Image credit: NASA/JPL-Caltech.

    Oxygen is only produced by previous generations of stars, indicating that this galaxy is already old.

    9
    The first stars and galaxies in the Universe will be surrounded by neutral atoms of (mostly) hydrogen gas, which absorbs the starlight. We cannot yet observe this first starlight directly, but we can observe what happens after a bit of cosmic evolution, allowing us to infer when stars must have formed in great abundance. The first stars are made of hydrogen and helium alone, but produce copious amounts of oxygen, which show up in later generations of stars. (NICOLE RAGER FULLER / NATIONAL SCIENCE FOUNDATION)

    MACS1149-JD1 was imaged with microwave (ALMA), infrared (Spitzer), and optical (Hubble) data combined.

    NASA/Spitzer Infrared Telescope

    The results indicate that stars existed nearly 300 million years before our observations.

    10
    Our entire cosmic history is theoretically well-understood, but only qualitatively. It’s by observationally confirming and revealing various stages in our Universe’s past that must have occurred, like when the first stars and galaxies formed, that we can truly come to understand our cosmos. The Big Bang sets a fundamental limit to how far back we can see in any direction. (NICOLE RAGER FULLER / NATIONAL SCIENCE FOUNDATION)

    11
    As we’re exploring more and more of the Universe, we’re able to look farther away in space, which equates to farther back in time. The James Webb Space Telescope will take us to depths, directly, that our present-day observing facilities cannot match. (NASA / JWST AND HST TEAMS)

    NASA/ESA/CSA Webb Telescope annotated

    2021’s James Webb Space Telescope will image them firsthand.

    See the full article here .


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    “Starts With A Bang! is a blog/video blog about cosmology, physics, astronomy, and anything else I find interesting enough to write about. I am a firm believer that the highest good in life is learning, and the greatest evil is willful ignorance. The goal of everything on this site is to help inform you about our world, how we came to be here, and to understand how it all works. As I write these pages for you, I hope to not only explain to you what we know, think, and believe, but how we know it, and why we draw the conclusions we do. It is my hope that you find this interesting, informative, and accessible,” says Ethan

     
  • richardmitnick 10:39 pm on August 20, 2018 Permalink | Reply
    Tags: Ali Observatory on the Tibetan Plateau over 5100 metres above sea level, , , , , Possible site for new 12 metre optical telescope, SODAR testing with Fulcrum 3D’s sonar radar,   

    From University of New South Wales: ” In search of the best telescope location, UNSW astronomer and alumnus head to high places” 

    U NSW bloc

    From University of New South Wales

    21 Aug 2018
    Ivy Shih

    An international effort to pinpoint the site for a new telescope is relying on technology developed by a UNSW alumnus during his PhD.

    1
    Dr Colin Bonner (left) and Professor Michael Ashley on location at Ali Observatory. Photo: Colin Bonner

    It is a tale of North and South with an astronomical twist, with a UNSW astronomer and a UNSW PhD alumnus heading from Antarctica to the Tibetan Plateau to help find the best site for a new, 12-metre optical telescope.

    This year, Professor Michael Ashley from the School of Physics and alumnus Dr Colin Bonner travelled to Ali Observatory in western Tibet to lead the testing and installation of SODAR (Sound Detection and Ranging), a device the astronomers will use to decide where a new telescope is best located.

    Ali Observatory on the Tibetan Plateau over 5100 metres above sea level

    The road to Tibet was a journey from one extreme to another. Before Tibet, Professor Ashley and Dr Bonner had been on scientific expeditions deploying telescopes in some of the most remote locations of Antartica, including the South Pole itself at latitude 90S. To reach Ali Observatory, the pair had to travel from Tibet’s capital Lhasa to Nagari Gunsa airport, the fourth highest altitude airport in the world.

    Ali Observatory is situated on the Tibetan Plateau, at more than 5100 metres above sea level. It’s a good location for studying the night sky, due to the combination of its high altitude and predominantly dry seasonal conditions in the region.

    “In astronomy you want to be as high as you can be because it gets you above some of the atmosphere, where it is nice and cold and there is not much water vapour,” says Professor Ashley.

    “It’s an amazing location. Antarctica is amazing in more ways than one, but the Tibetan Plateau is like the surface of the moon, albeit with some tufts of hardy grass and a few yaks.”

    The pair limited their time at Ali Observatory to a few hours at a time, however, to reduce the risk of altitude sickness.

    “The photos don’t capture the feeling of being there – you really notice the difficulty of breathing,” says Professor Ashley.

    Ashley and Bonner travelled to Tibet to install a SODAR to help evaluate the stability of the atmosphere at the location.

    2
    Fulcrum 3D’s sonar radar (cone-shaped object in the centre) installed onsite at Ali Observatory. Photo: Colin Bonner

    Atmosphere stability is critical for astronomers: tens of metres difference between where a telescope is placed can make the difference between a blurry image of a star and a clear high-resolution one.

    Original versions of the SODAR were put through their paces in Antarctica, where Professor Ashley and Dr Bonner previously worked at an international observatory.

    Chinese astronomer collaborators onsite in Antarctica saw the SODAR’s effectiveness and called on the combined expertise of Professor Ashley and Dr Bonner to apply it at Ali Observatory.

    There are now plans to construct a 12-metre optical telescope in Tibet. This will be the latest addition to an international cluster of smaller telescopes from the United States and Japan.

    “A big part of the visit was assessing locations – there is no point in having a Ferrari-style telescope put on a site that would not produce optimal conditions for astronomers,” says Dr Bonner.

    “If you are going to put in money to build a telescope, you need to be absolutely sure it is the best location.”

    The device will remain at Ali Observatory for at least a couple of years to collect seasonal atmospheric data. The information will then be analysed by Fulcrum3D and astronomers at the National Astronomical Observatory of China and UNSW to determine the best location for the new telescope.

    See the full article here .


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    U NSW Campus

    Welcome to UNSW Australia (The University of New South Wales), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

    In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

     
  • richardmitnick 5:17 pm on August 20, 2018 Permalink | Reply
    Tags: , , , , , , , , , , The scientific theories battling to explain the universe   

    From CNN: “The scientific theories battling to explain the universe” 

    1
    From CNN

    August 17, 2018
    1
    FNAL’s Don Lincoln

    In human history, there have been many interesting and epic feuds — the Hatfields and McCoys, Bette Davis and Joan Crawford, or the Notorious B.I.G and Tupac. Many of us love to read in tabloids or history books about the salacious details of how the bad blood came to be.

    Just like these human characters, scientific theories can also fall into disagreement, causing just as much drama in the science world.

    Recently, a group of scientists claimed to have found a fatal tension between two of the scientific community’s most mind-blowing theories: superstrings and dark energy. If the authors are correct, one of the two theories is in trouble.

    Superstring theory is a candidate theory of everything, with the operative word being “candidate,” meaning it is not yet accepted by the scientific community. It tries to explain all observed phenomena of the universe with a single principle. At its core, it predicts that the smallest building blocks of the cosmos aren’t the familiar atoms and protons, neutrons, and electrons; nor are the smallest building blocks the even-smaller quarks and lepton that my colleagues and I have discovered. Instead, superstring theory suggests that the very smallest building blocks of all are tiny and vibrating “strings.”

    These strings can vibrate in different ways — essentially different notes — with each note looking like one of the known subatomic particles. Waxing slightly poetic, superstring theory explains the universe as a vast and cosmic symphony.

    The other popular theory, called dark energy, is quite different. Astronomers have long known that the universe is expanding. For decades, we thought we understood that, because gravity is an attractive force, this expansion would slow over the lifetime of the universe. It was therefore a surprise when, in 1998, astronomers discovered that not only was the expansion of the universe not slowing down — it was speeding up.

    To explain this observation, astronomers added a type of energy — called dark energy — to Einstein’s equations describing the behavior of gravity. Dark energy is an energy field that permeates the entire universe. And, because the expansion of the universe is accelerating, dark energy must exist and it must be positive. The reason we know that is simple. If the dark energy didn’t exist or was negative, the expansion of the universe would be slowing down.

    So, what is it about these two theories that has caused such a conflict?

    In a nutshell, it’s hard to make a superstring theory with positive energy and yet the accelerating expansion of the universe demands it. If one theory is completely accurate it means that a key aspect of the other is wrong. And, on the face of it, things look bad for superstring theory. This is because while dark energy is still a theory, the accelerating expansion of the universe is not. Thus, dark energy is probably true, while superstring theory still remains only a conjecture.

    But there’s a reason that scientists aren’t rushing to media platforms to spread the news that superstring theory has been disproved.

    It’s because superstring theory is fiendishly complex. Aside from the prediction of subatomic vibrating strings, it also predicts that there are more dimensions of space than our familiar three. In fact, the theory predicts that there are nine in total — 10 if you include time. You’d think that this would be a fatal flaw of the theory, but these additional dimensions are thought to be invisibly small.

    Since these extra dimensions (if they exist) are smaller than our best instrumentation can detect, we don’t know what their shapes are, and scientists must consider all possibilities. But there are a lot of possibilities. In fact, there are more configurations than there are atoms in a million universes just like ours. It’s a crazy big number.

    So, what conclusion can we draw?

    With so many possible configurations, it would seem that superstring theory could predict just about anything, yet the scientists who pointed out the theories’ disagreement are making the bold claim that none of these configurations result in the existence of a positive and constant energy (aka, the theory of dark energy).

    And all the data recorded so far have made scientists feel relatively confident that dark energy not only exists, but is also both positive and nearly constant, making it seem likely that, if only one of these theories can be true, it’s dark energy for the win. Still, it’s premature to make any conclusions about the superstrings. It’s possible that scientists are not right about the nature of dark energy and they are using powerful instruments like the Dark Energy Survey to refine their measurements.

    The bottom line is that physicists are going to have to take this new idea seriously. It’s not quite a WWE cage match, but it’s going to be fun to watch these theories fight it out.

    See the full article here .

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  • richardmitnick 4:53 pm on August 20, 2018 Permalink | Reply
    Tags: , , , , , Milky Way galactic disc, Star density map   

    From European Space Agency: “Star density map released” 

    ESA Space For Europe Banner

    From European Space Agency

    1
    Star density map
    Released 20/08/2018
    Copyright Galaxy Map / K. Jardine

    20/08/2018

    The second data release of ESA’s Gaia mission, made in April, has marked a turning point in the study of our Galactic home, the Milky Way.

    ESA/GAIA satellite

    Milky Way Galaxy Credits: NASA/JPL-Caltech/R. Hurt

    With an unprecedented catalogue of 3D positions and 2D motions of more than a billion stars, plus additional information on smaller subsets of stars and other celestial sources, Gaia has provided astronomers with an astonishing resource to explore the distribution and composition of the Galaxy and to investigate its past and future evolution.

    The majority of stars in the Milky Way are located in the Galactic disc, which has a flattened shape characterised by a pattern of spiral arms similar to that observed in spiral galaxies beyond our own. However, it is particularly challenging to reconstruct the distribution of stars in the disc, and especially the design of the Milky Way’s arms, because of our position within the disc itself.

    This is where Gaia’s measurements can make the difference.

    This image shows a 3D map obtained by focusing on one particular type of object: OB stars, the hottest, brightest and most massive stars in our Galaxy. Because these stars have relatively short lives – up to a few tens of million years – they are mostly found close to their formation sites in the Galactic disc. As such, they can be used to trace the overall distribution of young stars, star formation sites, and the Galaxy’s spiral arms.

    The map, based on 400 000 of this type of star within less than 10 000 light-years from the Sun, was created by Kevin Jardine, a software developer and amateur astronomer with an interest in mapping the Milky Way using a variety of astronomical data.

    It is centred on the Sun and shows the Galactic disc as if we were looking at it face-on from a vantage point outside the Galaxy.

    To deal with the massive number of stars in the Gaia catalogue, Kevin made use of so-called density isosurfaces, a technique that is routinely used in many practical applications, for example to visualise the tissue of organs of bones in CT scans of the human body. In this technique, the 3D distribution of individual points is represented in terms of one or more smooth surfaces that delimit regions with a different density of points.

    Here, regions of the Galactic disc are shown with different colours depending on the density of ionising stars recorded by Gaia; these are the hottest among OB stars, shining with ultraviolet radiation that knocks electrons off hydrogen atoms to give them their ionized state.

    The regions with the highest density of these stars are displayed in pink/purple shades, regions with intermediate density in violet/light blue, and low-density regions in dark blue. Additional information from other astronomical surveys was also used to map concentrations of interstellar dust, shown in green, while known clouds of ionised gas are depicted as red spheres.

    The appearance of ‘spokes’ is a combination of dust clouds blocking the view to stars behind them and a stretching effect of the distribution of stars along the line of sight.

    An interactive version of this map is also available as part of Gaia Sky, a real-time, 3D astronomy visualisation software that was developed in the framework of the Gaia mission at the Astronomisches Rechen-Institut, University of Heidelberg, Germany.

    Further details including annotated version of the map: Mapping and visualising Gaia DR2

    See the full article here .

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    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 4:33 pm on August 20, 2018 Permalink | Reply
    Tags: , Anomalies, Bosons and fermions, Branes, , , , , Murray Gell-Mann, Parity violation, , , , , , , The second superstring revolution, Theorist John Schwarz   

    From Caltech: “Long and Winding Road: A Conversation with String Theory Pioneer” John Schwarz 

    Caltech Logo

    From Caltech

    08/20/2018

    Whitney Clavin
    (626) 395-1856
    wclavin@caltech.edu

    John Schwarz discusses the history and evolution of superstring theory.

    1
    John Schwarz. Credit: Seth Hansen for Caltech

    The decades-long quest for a theory that would unify all the known forces—from the microscopic quantum realm to the macroscopic world where gravity dominates—has had many twists and turns. The current leading theory, known as superstring theory and more informally as string theory, grew out of an approach to theoretical particle physics, called S-matrix theory, which was popular in the 1960s. Caltech’s John H. Schwarz, the Harold Brown Professor of Theoretical Physics, Emeritus, began working on the problem in 1971, while a junior faculty member at Princeton University. He moved to Caltech in 1972, where he continued his research with various collaborators from other universities. Their studies in the 1970s and 1980s would dramatically shift the evolution of the theory and, in 1984, usher in what’s known as the first superstring revolution.

    Essentially, string theory postulates that our universe is made up, at its most fundamental level, of infinitesimal tiny vibrating strings and contains 10 dimensions—three for space, one for time, and six other spatial dimensions curled up in such a way that we don’t perceive them in everyday life or even with the most sensitive experimental searches to date. One of the many states of a string is thought to correspond to the particle that carries the gravitational force, the graviton, thereby linking the two pillars of fundamental physics—quantum mechanics and the general theory of relativity, which includes gravity.

    We sat down with Schwarz to discuss the history and evolution of string theory and how the theory itself might have moved past strings.

    What are the earliest origins of string theory?

    The first study often regarded as the beginning of string theory came from an Italian physicist named Gabriele Veneziano in 1968. He discovered a mathematical formula that had many of the properties that people were trying to incorporate in a fundamental theory of the strong nuclear force [a fundamental force that holds nuclei together]. This formula was kind of pulled out of the blue, and ultimately Veneziano and others realized, within a couple years, that it was actually describing a quantum theory of a string—a one-dimensional extended object.

    How did the field grow after this paper?

    In the early ’70s, there were several hundred people worldwide working on string theory. But then everything changed when quantum chromodynamics, or QCD—which was developed by Caltech’s Murray Gell-Mann [Nobel Laureate, 1969] and others—became the favored theory of the strong nuclear force. Almost everyone was convinced QCD was the right way to go and stopped working on string theory. The field shrank down to just a handful of people in the course of a year or two. I was one of the ones who remained.

    How did Gell-Mann become interested in your work?

    Gell-Mann is the one who brought me to Caltech and was very supportive of my work. He took an interest in studies I had done with a French physicist, André Neveu, when we were at Princeton. Neveu and I introduced a second string theory. The initial Veneziano version had many problems. There are two kinds of fundamental particles called bosons and fermions, and the Veneziano theory only described bosons. The one I developed with Neveu included fermions. And not only did it include fermions but it led to the discovery of a new kind of symmetry that relates bosons and fermions, which is called supersymmetry. Because of that discovery, this version of string theory is called superstring theory.

    When did the field take off again?

    A pivotal change happened after work I did with another French physicist, Joël Scherk, whom Gell-Mann and I had brought to Caltech as a visitor in 1974. During that period, we realized that many of the problems we were having with string theory could be turned into advantages if we changed the purpose. Instead of insisting on constructing a theory of the strong nuclear force, we took this beautiful theory and asked what it was good for. And it turned out it was good for gravity. Neither of us had worked on gravity. It wasn’t something we were especially interested in but we realized that this theory, which was having trouble describing the strong nuclear force, gives rise to gravity. Once we realized this, I knew what I would be doing for the rest of my career. And I believe Joël felt the same way. Unfortunately, he died six years later. He made several important discoveries during those six years, including a supergravity theory in 11 dimensions.

    Surprisingly, the community didn’t respond very much to our papers and lectures. We were generally respected and never had a problem getting our papers published, but there wasn’t much interest in the idea. We were proposing a quantum theory of gravity, but in that era physicists who worked on quantum theory weren’t interested in gravity, and physicists who worked on gravity weren’t interested in quantum theory.

    That changed after I met Michael Green [a theoretical physicist then at the University of London and now at the University of Cambridge], at the CERN cafeteria in Switzerland in the summer of 1979. Our collaboration was very successful, and Michael visited Caltech for several extended visits over the next few years. We published a number of papers during that period, which are much cited, but our most famous work was something we did in 1984, which had to do with a problem known as anomalies.

    What are anomalies in string theory?

    One of the facts of nature is that there is what’s called parity violation, which means that the fundamental laws are not invariant under mirror reflection. For example, a neutrino always spins clockwise and not counterclockwise, so it would look wrong viewed in a mirror. When you try to write down a fundamental theory with parity violation, mathematical inconsistencies often arise when you take account of quantum effects. This is referred to as the anomaly problem. It appeared that one couldn’t make a theory based on strings without encountering these anomalies, which, if that were the case, would mean strings couldn’t give a realistic theory. Green and I discovered that these anomalies cancel one another in very special situations.

    When we released our results in 1984, the field exploded. That’s when Edward Witten [a theoretical physicist at the Institute for Advanced Study in Princeton], probably the most influential theoretical physicist in the world, got interested. Witten and three collaborators wrote a paper early in 1985 making a particular proposal for what to do with the six extra dimensions, the ones other than the four for space and time. That proposal looked, at the time, as if it could give a theory that is quite realistic. These developments, together with the discovery of another version of superstring theory, constituted the first superstring revolution.

    Richard Feynman was here at Caltech during that time, before he passed away in 1988. What did he think about string theory?

    After the 1984 to 1985 breakthroughs in our understanding of superstring theory, the subject no longer could be ignored. At that time it acquired some prominent critics, including Richard Feynman and Stephen Hawking. Feynman’s skepticism of superstring theory was based mostly on the concern that it could not be tested experimentally. This was a valid concern, which my collaborators and I shared. However, Feynman did want to learn more, so I spent several hours explaining the essential ideas to him. Thirty years later, it is still true that there is no smoking-gun experimental confirmation of superstring theory, though it has proved its value in other ways. The most likely possibility for experimental support in the foreseeable future would be the discovery of supersymmetry particles. So far, they have not shown up.

    What was the second superstring revolution about?

    The second superstring revolution occurred 10 years later in the mid ’90s. What happened then is that string theorists discovered what happens when particle interactions become strong. Before, we had been studying weakly interacting systems. But as you crank up the strength of the interaction, a 10th dimension of space can emerge. New objects called branes also emerge. Strings are one dimensional; branes have all sorts of dimensions ranging from zero to nine. An important class of these branes, called D-branes, was discovered by the late Joseph Polchinski [BS ’75]. Strings do have a special role, but when the system is strongly interacting, then the strings become less fundamental. It’s possible that in the future the subject will get a new name but until we understand better what the theory is, which we’re still struggling with, it’s premature to invent a new name.

    What can we say now about the future of string theory?

    It’s now over 30 years since a large community of scientists began pooling their talents, and there’s been enormous progress in those 30 years. But the more big problems we solve, the more new questions arise. So, you don’t even know the right questions to ask until you solve the previous questions. Interestingly, some of the biggest spin-offs of our efforts to find the most fundamental theory of nature are in pure mathematics.

    Do you think string theory will ultimately unify the forces of nature?

    Yes, but I don’t think we’ll have a final answer in my lifetime. The journey has been worth it, even if it did take some unusual twists and turns. I’m convinced that, in other intelligent civilizations throughout the galaxy, similar discoveries will occur, or already have occurred, in a different sequence than ours. We’ll find the same result and reach the same conclusions as other civilizations, but we’ll get there by a very different route.

    See the full article here .

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    Please help promote STEM in your local schools.

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    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

     
  • richardmitnick 2:56 pm on August 20, 2018 Permalink | Reply
    Tags: , , Computer science pared with marketing expertise, Cornell Tech in NYC, In New York’s tech sector gender ethnic and racial diversity start in the classroom, New York tech is a melting pot of startups and established companies and industries, New York’s thriving tech industry is no Silicon Valley and that’s just fine, Technology, The Big Apple is in a unique position to address a diversity problem that plagues the tech industry on the opposite coast, The Samuel Curtis Johnson Graduate School of Management and Cornell Tech officially relocated to Cornell Tech’s 12-acre campus on Manhattan’s Roosevelt Island in fall 2017, The Samuel Curtis Johnson Graduate School of Management and Cornell Tech started the Johnson Cornell Tech MBA program in 2014   

    From Cornell Tech: “A Quiet Revolution” 

    From Cornell Tech

    Cornell Tech NYC A Quiet Revolution

    Far from the oft-criticized homogeneity of Silicon Valley, New York’s very identity is a reflection of its eclectic mix of races and cultures. That puts the Big Apple in a unique position to address a diversity problem that plagues the tech industry on the opposite coast. From fashion to finance, New York tech is a melting pot of startups, established companies and industries. And the Johnson Cornell Tech MBA program channels the variety of backgrounds, perspectives and professions to foster multidisciplinary thinkers who can diversify an overwhelmingly white and male tech industry in the United States.

    A focus on diversity attracts tech talent to the city, according to a 2018 survey by the nonprofit Tech: NYC, with 89 percent of respondents citing the diverse population as a draw and 74 percent citing the variety of industries to choose from as a lure. “Diversity is very important for innovation, as people with different perspectives, training, backgrounds and cultures come together to look at the same problem differently,” said Erik Grimmelmann, president of the nonprofit NY Tech Alliance.

    1
    Students gather outside the Tata Innovation Center.

    Being Deliberate About Diversity

    In New York’s tech sector, gender, ethnic and racial diversity start in the classroom. The Samuel Curtis Johnson Graduate School of Management and Cornell Tech started the Johnson Cornell Tech MBA program in 2014, taking up temporary residence in Google office space in New York and officially relocating to Cornell Tech’s 12-acre campus on Manhattan’s Roosevelt Island in fall 2017. The program has since attracted women, minorities and international students with resumes and interests from an array of backgrounds.

    “The amazing thing about building an [academic program] from scratch is that you can be really deliberate about important things like diversity,” said Julie Samuels, the executive director of Tech:NYC, which supports the city’s tech sector.

    3
    Professor Mukti Khaire teaches entrepreneurship in creative industries at Cornell Tech.

    The Johnson Cornell Tech MBA program was built around the concept that the best leaders and innovators have a variety of skill sets, and that they seek out unique perspectives in others. That’s evident in the way student teams in the program’s Studio curriculum mimic the most successful tech companies, said Mukti Khaire, the Girish and Jaidev Reddy Professor of Practice at Cornell Tech and the Cornell SC Johnson College of Business.

    Some projects might see a computer scientist paired with, say, a market expert and a designer. “There’s nothing better than to show students that diversity is important in these teams for really creative problem solving,” Khaire said.

    John Quinn, who graduated in spring 2018, said he had to up his game academically and creatively because of the mix of races, ages and backgrounds. Quinn’s career was on track, with him working in digital payments at MasterCard in Dublin, his hometown. But he realized tech expertise alone wasn’t enough to continue advancing at the company. Now, with a Johnson Cornell Tech MBA, he’s starting a new role at MasterCard’s NYC Technology Hub.

    For Quinn, diversity and inclusion workshops on campus were also eye openers.

    “It was amazing how honest people could be,” he said, referring to sessions in which women and minorities spoke about the challenges they face in tech. “It will make me a better co-worker and a better manager to be aware of these things.”

    ‘A Force to Be Reckoned With’ in NYC

    New York’s large and diverse network of students, workers and entrepreneurs attracts tech professionals who might otherwise have headed to Silicon Valley. On the West Coast, “You get a lot of homogeneity in thought and how people approach problems,” said David Cheng, a 2017 Cornell Tech MBA grad.

    That’s a big reason Cheng, a former software engineer and consultant in Washington, chose New York to start a mobile speech therapy app he developed with classmates. Just last year, Speech Up won Cornell Tech’s Startup Award, which included workspace at its Tata Innovation Center, where students and companies work to bring new ideas to market.

    4
    The Emma and Georgina Bloomberg Center, across from the Manhattan skyline.

    Cheng, who attended speech therapy sessions as a child, said he was drawn to New York because so many of its industries are reinventing themselves through tech. “Being part of the community that is doing that is something that really appealed to me,” he said.

    Kendall Jakes, also a 2017 Cornell Tech MBA grad, said the program’s multicultural and multidisciplinary approach attracted her as well. She worked for a Chicago food company in a role that combined technology and business. But as she looked into M.B.A. programs to help with her next career, she found most wanted to put her in either a tech or a business “bucket.”

    6
    7
    Above: David Cheng, class of 2017. Below: John Quinn, a 2018 graduate.

    “That isn’t how the world works. Why should we be siloed?” said Jakes, now a technical solutions specialist at Microsoft’s New York office, adding that the Johnson Cornell Tech MBA program was a place where she was totally accepted.

    Jakes also said she loved that her class was 40 percent female, a contrast to the broader U.S. tech workforce, which is 76 percent male. “We were a force to be reckoned with,” she said.

    A Model for Tomorrow’s Tech Sector

    New York’s thriving tech industry is no Silicon Valley, and that’s just fine, said Grimmelmann, the NY Tech Alliance president.

    “Out West, it’s all tech, all the time,” he said. Conversely, New York mixes tech with other disciplines and radically changes them. FinTech, EdTech and HealthTech, for example, are flourishing in the city.

    Diversity in industries, cultures and backgrounds creates the best innovators and leaders, said Samuels, Tech:NYC’s executive director. “The most successful employees,” she said, “are the ones who are really good at problem solving and can navigate a fast-growing company — versus stay in your lane and do your own job.”

    8
    Kendall Jakes is a 2017 Cornell Tech MBA grad.

    Jakes agrees. In New York — and in the Johnson Cornell Tech MBA program — she doesn’t feel pigeonholed, she said, but rather celebrated for being a “creative techie.”

    “I love the energy here,” Jakes said. “That’s something really different about New York.”

    Explore

    See the full article here .

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    Original announcment
    Cornell Tech today celebrated the official opening of its campus on Roosevelt Island with a dedication event attended by New York Governor Andrew Cuomo, New York City Mayor Bill de Blasio, former Mayor Mike Bloomberg, Cornell University President Martha Pollack, Technion President Peretz Lavie and Cornell Tech Dean Daniel Huttenlocher. Cornell Tech is the first campus ever built for the digital age, bringing together academia and industry to create pioneering leaders and transformational new research, products, companies and social ventures. Today marks the opening of the first phase of the Roosevelt Island campus, which features some of the most environmentally friendly and energy-efficient buildings in the world.

    In 2011, Cornell Tech was named the winner of Mayor Mike Bloomberg’s Administration’s visionary Applied Sciences Competition, designed with the goal of diversifying the economy and creating a national hub for tech. The project, managed by the City’s Economic Development Corporation, has been carried forward by the de Blasio administration, with the campus breaking ground in 2015. The City estimated in 2011 that the new campus would generate up to 8,000 permanent jobs, hundreds of spin-off companies and more than $23 billion in economic activity over a period of 35 years. The campus is built on 12 acres of City land.

    “With the opening of Cornell Tech, Cornell University, in partnership with the Technion, is defining a new model for graduate education — a model that melds cutting-edge research and education with entrepreneurship and real world application,” said Cornell University President Martha E. Pollack. “We are so grateful to the City of New York for offering us a chance to launch this venture, to the many other partners who have helped bring us to this day, and to Mayor de Blasio and his administration for their continued commitment and support. Today marks the beginning of a new era of opportunity not only for Cornell and the tech campus, but also for New York City, the state and the world.”

    “Today’s Cornell Tech campus opening marks the beginning of a new chapter in the Jacobs Technion-Cornell Institute’s ongoing work to foster innovation in New York and beyond,” said Professor Peretz Lavie, President of Technion-Israel Institute of Technology. “In partnership with Cornell, we’ve developed a model of graduate-level technology education that is unlike any other – one that’s tailor-made not only for New York City but for the challenges of the digital revolution.”

    “Thanks to our investments to foster key industries, create good-paying jobs, and attract top talent, New York is the center of the world for finance, advertising, media, the arts and international commerce, but we are still building our reputation as an internationally-recognized hub of cutting-edge science and technology. By harnessing the engineering expertise of Cornell and the entrepreneurial spirit of Technion, Cornell Tech’s new campus will strengthen New York’s future competitiveness and produce innovations that will change the world,” said Governor Andrew Cuomo.

    “As we work to keep New York City a leader in the 21st Century economy, we celebrate the opening of the Cornell Tech campus and the opportunities it opens up for our city and our people. I am proud to welcome our newest leading educational institution, which will become a tremendous catalyst for our tech sector. We won’t stop here. Through Computer Science for All, the Tech Talent Pipeline and the new Union Square Tech Hub, we are building on the progress Mayor Bloomberg set in motion, and helping more New Yorkers become a part of this extraordinary success story,” said Mayor Bill de Blasio.

    “Cornell Tech is an investment in the future of New York City — a future that belongs to the generations to come, and the students here will help build it. Technological innovation played a central role in New York City becoming a global economic capital – and it must continue to play a central role for New York to remain a global economic capital. The companies and innovations spawned by Cornell Tech graduates will generate jobs for people across the economic spectrum and help our city compete with tech centers around the world, from Silicon Valley to Seoul,” said Mike Bloomberg.

    “I’m thrilled that the Cornell Tech campus is finally opening on Roosevelt Island,” said Congresswoman Carolyn B. Maloney.“With its proximity to Manhattan and to industrial space in Western Queens, Roosevelt Island is the perfect setting for an educational institution, which is which is why I worked hard to ensure that it was selected when the City was considering locations for the new applied science campus. Cornell Tech will help us diversify our economic base and bring jobs through new startups. A New York school generates New York businesses and employs New Yorkers. As students are welcomed to the new campus, we know this is just the beginning – and that the future for this institution will be bright.”

    “Cornell Tech will create the leaders of tomorrow, bringing the brightest minds in the field of technology to Roosevelt Island. The digital age has not only improved the efficiency and productivity at the workplace, but created competitive high-paying salaries and stable jobs that keep overall unemployment rates lower. Cornell Tech is ahead of the curve by providing academic programs and training that will make this a world-renowned institution,” said Assembly Member Rebecca A. Seawright.

    “The new Cornell Tech campus is a wonderful addition to Roosevelt Island and will continue to propel New York City as a leader in technology and innovation. Not only will this state of the art campus generate thousands of permanent jobs and billions of dollars in economic activity over the next 30 years, but is also environmentally friendly and energy efficient. Many thanks to Cornell Tech and all of my colleagues in government and on Roosevelt Island that helped to complete this special project,” said New York State Senator José M. Serrano.

    “This milestone is a game-changer – and this campus is a New York City gem. As it prepares students for jobs of the future today, Cornell Tech will keep our city competitive in emerging industries tomorrow. This transformative project truly cements New York City as a global tech hub, and it illustrates what happens when government, academia, and industry all work together. Every stakeholder in this project should be exceptionally proud,” said Comptroller Scott M. Stringer.

    “As our world becomes more tech-centered, the Cornell Tech campus will allow New York City to be at the heart of the innovation, leadership — and most importantly, jobs — in this space. This campus will bring academics, research and business together and educate the bright minds of our future. I look forward to seeing all that Cornell Tech has to offer our City, and to working with Cornell Tech to ensure that New Yorkers from every corner of our City benefit from this world-class institution,” said Public Advocate Letitia James.

    “Cornell Tech is a tremendous boost to New York’s growing tech community and a welcome addition to our city’s pantheon of world-class academic institutions,” said Manhattan Borough President Gale A. Brewer. “It’s been thrilling to watch the campus’ buildings rise on Roosevelt Island and to see the community partnerships this institution has already made possible.”

    “The dedication of the Cornell Tech campus is an incredible achievement for New York City that has been almost seven years in the making,” said New York City Council Speaker Melissa Mark-Viverito. “Not only does the addition of this institution enhance an already impressive slate of educational offerings, but its presence brings New York City’s drive for innovation to the cutting edge. I look forward to the thousands of students and faculty who will bring their research and insights to the five boroughs, and I am proud of the partnership between Cornell, the Technion Israel Institute of Technology and the New York City Council that saw about $300,000 allocated toward making this dream a reality.”

    “The opening of Cornell Tech on Roosevelt Island is a victory for Western Queens and New York City that will create jobs and reassert the region as a global leader in tech and innovation,” said City Council Majority Leader Jimmy Van Bramer. “Just one stop on the F train to Western Queens, the proximity of the new campus and tech incubator to Western Queens will be beneficial for the people of my district and for the students of Cornell Tech looking to start new businesses. With unmatched resources for small businesses, including a diverse and talented workforce, Long Island City will be a natural place for new tech businesses to call home, develop breakthroughs, and create jobs. I thank all involved in this historic project for their good work and look forward to working closely with our new neighbor, Cornell Tech.”

    “Tech now has a new home in New York City on Roosevelt Island at Cornell Tech. We are growing jobs and educating the next leaders of the tech economy right here on Roosevelt Island so the next big thing in tech will be ‘Made in New York,” said City Council Member Ben Kallos, a tech entrepreneur. “Welcome to Cornell Tech, Dean Dan Huttenlocher and thank you to former Mayor Michael Bloomberg for the vision, Mayor de Blasio and RIOC President Susan Rosenthal for making it happen, and the Roosevelt Island community for being a part of this every step of the way. I look forward to working with Cornell Tech on bringing millions in investment to growing companies on Roosevelt Island and in New York City.”

    Academic Program & Research

    Cornell Tech started up in a temporary space generously provided by Google and has already graduated more than 300 masters and doctoral students, with most entering the New York City tech sector after graduation by joining local companies or starting their own. Masters students across all programs — computer science, law, business, electrical engineering, operations research, connective media and health tech — spend time learning and working collaboratively together in a Studio curriculum with extensive engagement with the tech industry. The projects students pursue in the Studio encourage them to practice entrepreneurship, product design, tech and public policy, management and other skills, helping them graduate with tangible, marketable experience and a portfolio of completed work that will help launch their career.

    Cornell Tech’s 30-member faculty has launched cutting-edge research groups in the areas of Human-Computer Interaction and Social Computing, Security and Privacy, Artificial Intelligence, Data and Modeling, and Business, Law and Policy. All of the faculty have a focus on applied research and having a real world impact.

    “We are entering a new era for tech in New York, and the Cornell Tech campus is at the heart of it. Cornell Tech was given the rare opportunity to create a campus and academic program from scratch. The opening of our new campus brings together academic disciplines critical to the digital transformation of society and the economy, together with companies, early stage investors, and government to spark innovation and help improve the lives of people throughout the City, country and world,” said Cornell Tech Dean Daniel Huttenlocher.

    “Cornell Tech is a natural 21st-century expression of Cornell University’s founding principles,” said Robert S. Harrison, chairman of the Cornell University Board of Trustees. “The new campus is both completely transformative – and completely consistent with our values and our mission to pursue knowledge with a public purpose. While Ithaca remains the heart of the university, we serve New Yorkers through outreach and engagement in all 62 counties of New York state and have been deeply integrated in New York City for more than a century. The innovative programs at Cornell Tech affirm our institution’s vision, enhance our land-grant mission, and reflect the spirit of all Cornellians.”

    The Jacobs Technion-Cornell Institute at Cornell Tech is a unique academic partnership of two leading global universities, the Technion Israel Institute of Technology and Cornell. The Institute houses the Health Tech and Connective Media programs, where students receive dual degrees from Cornell and the Technion, and the Jacobs Runway Startup Postdoc program for recent tech PhDs.The Runway program has been responsible for about half of the more than 30 companies that have spun out of the Cornell Tech campus with more than $20 million in funds raised and employing more than 100 people.

    “The Jacobs Technion-Cornell Institute is a cornerstone of Cornell Tech, combining Cornell’s commitment to discovery with Technion’s global leadership in applied research and entrepreneurship. From our dual masters degree programs, to our groundbreaking faculty research, to the innovative companies spinning out of the Jacobs Runway Startup Postdoc program, our partnership and impact will grow on our new campus. Through the Jacobs Institute, Cornell Tech and New York City as a whole will always be on the leading edge, experimenting with novel ways to educate, discover, and innovate,” said Ron Brachman, Director of the Jacobs Technion-Cornell Institute.

    “By steering students through Cornell Tech, and its soon-to-come Verizon Executive Education Center, we can build students and business people into lifelong learners and inspire them to be more innovative and impactful leaders. Our investment in Cornell Tech, is a testament of our belief that technology can be a transforming force in our society. This unique institution will be a model for the future and a shining example of how to solve big challenges and make people’s lives better,” said Lowell McAdam, Chairman and CEO of Verizon.

    “Even without a permanent campus, Cornell Tech has already established a proven track record of developing innovative companies and top tier talent here in New York City. Now in its beautiful new home on Roosevelt Island, Cornell Tech immediately establishes itself as one of New York’s premier tech institutions—helping us attract and retain the technical talent and companies our industry needs to grow and thrive,” said Julie Samuels, Executive Director of Tech:NYC.

     
  • richardmitnick 11:06 am on August 20, 2018 Permalink | Reply
    Tags: , , , , ,   

    From European Space Agency: “Infant exoplanet weighed by Hipparcos and Gaia” 

    ESA Space For Europe Banner

    From European Space Agency

    20 August 2018

    The mass of a very young exoplanet has been revealed for the first time using data from ESA’s star mapping spacecraft Gaia and its predecessor, the quarter-century retired Hipparcos satellite.

    Astronomers Ignas Snellen and Anthony Brown from Leiden University, the Netherlands, deduced the mass of the planet Beta Pictoris b from the motion of its host star over a long period of time as captured by both Gaia and Hipparcos. ([Nature Astronomy])

    2
    Beta Pictoris system

    ESA/GAIA satellite

    ESA/Hipparcos satellite

    The planet is a gas giant similar to Jupiter but, according to the new estimate, is 9 to 13 times more massive. It orbits the star Beta Pictoris, the second brightest star in the constellation Pictor.

    The planet was only discovered in 2008 in images captured by the Very Large Telescope at the European Southern Observatory in Chile.

    ESO VLT at Cerro Paranal in the Atacama Desert, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).
    elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo

    Both the planet and the star are only about 20 million years old – roughly 225 times younger than the Solar System. Its young age makes the system intriguing but also difficult to study using conventional methods.

    “In the Beta Pictoris system, the planet has essentially just formed,” says Ignas. “Therefore we can get a picture of how planets form and how they behave in the early stages of their evolution. On the other hand, the star is very hot, rotates fast, and it pulsates.”

    This behaviour makes it difficult for astronomers to accurately measure the star’s radial velocity – the speed at which it appears to periodically move towards and away from the Earth. Tiny changes in the radial velocity of a star, caused by the gravitational pull of planets in its vicinity, are commonly used to estimate masses of exoplanets. But this method mainly works for systems that have already gone through the fiery early stages of their evolution.

    In the case of Beta Pictoris b, upper limits of the planet’s mass range had been arrived at before using the radial velocity method. To obtain a better estimate, the astronomers used a different method, taking advantage of Hipparcos’ and Gaia’s measurements that reveal the precise position and motion of the planet’s host star in the sky over time.

    2
    Astrometric measurements to detect exoplanets

    “The star moves for different reasons,” says Ignas. “First, the star circles around the centre of the Milky Way, just as the Sun does. That appears from the Earth as a linear motion projected on the sky. We call it proper motion. And then there is the parallax effect, which is caused by the Earth orbiting around the Sun. Because of this, over the year, we see the star from slightly different angles.”

    And then there is something that the astronomers describe as ‘tiny wobbles’ in the trajectory of the star across the sky – minuscule deviations from the expected course caused by the gravitational pull of the planet in the star’s orbit.

    Planet transit. NASA/Ames

    This is the same wobble that can be measured via changes in the radial velocity, but along a different direction – on the plane of the sky, rather than along the line of sight.

    Radial Velocity Method-Las Cumbres Observatory


    Radial velocity Image via SuperWasp http:// http://www.superwasp.org/exoplanets.htm

    “We are looking at the deviation from what you expect if there was no planet and then we measure the mass of the planet from the significance of this deviation,” says Anthony. “The more massive the planet, the more significant the deviation.”

    To be able to make such an assessment, astronomers need to observe the trajectory of the star for a long period of time to properly understand the proper motion and the parallax effect.

    The Gaia mission, designed to observe more than one billion stars in our Galaxy, will eventually be able to provide information about a large amount of exoplanets.

    In the 22 months of observations included in Gaia’s second data release, published in April, the satellite has recorded the star Beta Pictoris about thirty times. That, however, is not enough.

    “Gaia will find thousands of exoplanets, that’s still on our to-do list,” says Timo Prusti, ESA’s Gaia project scientist. “The reason that the exoplanets can be expected only late in the mission is the fact that to measure the tiny wobble that the exoplanets are causing, we need to trace the position of stars for several years.”

    Combining the Gaia measurements with those from ESA’s Hipparcos mission, which observed Beta Pictoris 111 times between 1990 and 1993, enabled Ignas and Anthony to get their result much faster.

    This led to the first successful estimate of a young planet’s mass using astrometric measurements.

    “By combining data from Hipparcos and Gaia, which have a time difference of about 25 years, you get a very long term proper motion,” says Anthony.

    “This proper motion also contains the component caused by the orbiting planet. Hipparcos on its own would not have been able to find this planet because it would look like a perfectly normal single star unless we had measured it for a much longer time.

    “Now, by combining Gaia and Hipparcos and looking at the difference in the long term and the short term proper motion, we can see the effect of the planet on the star.”

    The result represents an important step towards better understanding the processes involved in planet formation, and anticipates the exciting exoplanet discoveries that will be unleashed by Gaia’s future data releases.

    See the full article here .


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    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 9:49 am on August 20, 2018 Permalink | Reply
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    From MIT News: “Light from ancient quasars helps confirm quantum entanglement” 

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    MIT Widget

    From MIT News

    August 19, 2018
    Jennifer Chu

    1
    The quasar dates back to less than one billion years after the big bang. Image: NASA/ESA/G.Bacon, STScI

    2
    Courtesy of the researchers.

    Results are among the strongest evidence yet for “spooky action at a distance.”

    Last year, physicists at MIT, the University of Vienna, and elsewhere provided strong support for quantum entanglement, the seemingly far-out idea that two particles, no matter how distant from each other in space and time, can be inextricably linked, in a way that defies the rules of classical physics.

    Take, for instance, two particles sitting on opposite edges of the universe. If they are truly entangled, then according to the theory of quantum mechanics their physical properties should be related in such a way that any measurement made on one particle should instantly convey information about any future measurement outcome of the other particle — correlations that Einstein skeptically saw as “spooky action at a distance.”

    In the 1960s, the physicist John Bell calculated a theoretical limit beyond which such correlations must have a quantum, rather than a classical, explanation.

    But what if such correlations were the result not of quantum entanglement, but of some other hidden, classical explanation? Such “what-ifs” are known to physicists as loopholes to tests of Bell’s inequality, the most stubborn of which is the “freedom-of-choice” loophole: the possibility that some hidden, classical variable may influence the measurement that an experimenter chooses to perform on an entangled particle, making the outcome look quantumly correlated when in fact it isn’t.

    Last February, the MIT team and their colleagues significantly constrained [Physical Review Letters] the freedom-of-choice loophole, by using 600-year-old starlight to decide what properties of two entangled photons to measure. Their experiment proved that, if a classical mechanism caused the correlations they observed, it would have to have been set in motion more than 600 years ago, before the stars’ light was first emitted and long before the actual experiment was even conceived.

    Now, in a paper published today in Physical Review Letters, the same team has vastly extended the case for quantum entanglement and further restricted the options for the freedom-of-choice loophole. The researchers used distant quasars, one of which emitted its light 7.8 billion years ago and the other 12.2 billion years ago, to determine the measurements to be made on pairs of entangled photons. They found correlations among more than 30,000 pairs of photons, to a degree that far exceeded the limit that Bell originally calculated for a classically based mechanism.

    “If some conspiracy is happening to simulate quantum mechanics by a mechanism that is actually classical, that mechanism would have had to begin its operations — somehow knowing exactly when, where, and how this experiment was going to be done — at least 7.8 billion years ago. That seems incredibly implausible, so we have very strong evidence that quantum mechanics is the right explanation,” says co-author Alan Guth, the Victor F. Weisskopf Professor of Physics at MIT.

    “The Earth is about 4.5 billion years old, so any alternative mechanism — different from quantum mechanics — that might have produced our results by exploiting this loophole would’ve had to be in place long before even there was a planet Earth, let alone an MIT,” adds David Kaiser, the Germeshausen Professor of the History of Science and professor of physics at MIT. “So we’ve pushed any alternative explanations back to very early in cosmic history.”

    Guth and Kaiser’s co-authors include Anton Zeilinger and members of his group at the Austrian Academy of Sciences and the University of Vienna, as well as physicists at Harvey Mudd College and the University of California at San Diego.

    A decision, made billions of years ago

    In 2014, Kaiser and two members of the current team, Jason Gallicchio and Andrew Friedman, proposed an experiment to produce entangled photons on Earth — a process that is fairly standard in studies of quantum mechanics. They planned to shoot each member of the entangled pair in opposite directions, toward light detectors that would also make a measurement of each photon using a polarizer. Researchers would measure the polarization, or orientation, of each incoming photon’s electric field, by setting the polarizer at various angles and observing whether the photons passed through — an outcome for each photon that researchers could compare to determine whether the particles showed the hallmark correlations predicted by quantum mechanics.

    The team added a unique step to the proposed experiment, which was to use light from ancient, distant astronomical sources, such as stars and quasars, to determine the angle at which to set each respective polarizer. As each entangled photon was in flight, heading toward its detector at the speed of light, researchers would use a telescope located at each detector site to measure the wavelength of a quasar’s incoming light. If that light was redder than some reference wavelength, the polarizer would tilt at a certain angle to make a specific measurement of the incoming entangled photon — a measurement choice that was determined by the quasar. If the quasar’s light was bluer than the reference wavelength, the polarizer would tilt at a different angle, performing a different measurement of the entangled photon.

    In their previous experiment, the team used small backyard telescopes to measure the light from stars as close as 600 light years away. In their new study, the researchers used much larger, more powerful telescopes to catch the incoming light from even more ancient, distant astrophysical sources: quasars whose light has been traveling toward the Earth for at least 7.8 billion years — objects that are incredibly far away and yet are so luminous that their light can be observed from Earth.

    Tricky timing

    On Jan. 11, 2018, “the clock had just ticked past midnight local time,” as Kaiser recalls, when about a dozen members of the team gathered on a mountaintop in the Canary Islands and began collecting data from two large, 4-meter-wide telescopes: the William Herschel Telescope and the Telescopio Nazionale Galileo, both situated on the same mountain and separated by about a kilometer.

    One telescope focused on a particular quasar, while the other telescope looked at another quasar in a different patch of the night sky. Meanwhile, researchers at a station located between the two telescopes created pairs of entangled photons and beamed particles from each pair in opposite directions toward each telescope.

    In the fraction of a second before each entangled photon reached its detector, the instrumentation determined whether a single photon arriving from the quasar was more red or blue, a measurement that then automatically adjusted the angle of a polarizer that ultimately received and detected the incoming entangled photon.

    “The timing is very tricky,” Kaiser says. “Everything has to happen within very tight windows, updating every microsecond or so.”

    Demystifying a mirage

    The researchers ran their experiment twice, each for around 15 minutes and with two different pairs of quasars. For each run, they measured 17,663 and 12,420 pairs of entangled photons, respectively. Within hours of closing the telescope domes and looking through preliminary data, the team could tell there were strong correlations among the photon pairs, beyond the limit that Bell calculated, indicating that the photons were correlated in a quantum-mechanical manner.

    Guth led a more detailed analysis to calculate the chance, however slight, that a classical mechanism might have produced the correlations the team observed.

    He calculated that, for the best of the two runs, the probability that a mechanism based on classical physics could have achieved the observed correlation was about 10 to the minus 20 — that is, about one part in one hundred billion billion, “outrageously small,” Guth says. For comparison, researchers have estimated the probability that the discovery of the Higgs boson was just a chance fluke to be about one in a billion.

    “We certainly made it unbelievably implausible that a local realistic theory could be underlying the physics of the universe,” Guth says.

    And yet, there is still a small opening for the freedom-of-choice loophole. To limit it even further, the team is entertaining ideas of looking even further back in time, to use sources such as cosmic microwave background photons that were emitted as leftover radiation immediately following the Big Bang, though such experiments would present a host of new technical challenges.

    “It is fun to think about new types of experiments we can design in the future, but for now, we are very pleased that we were able to address this particular loophole so dramatically. Our experiment with quasars puts extremely tight constraints on various alternatives to quantum mechanics. As strange as quantum mechanics may seem, it continues to match every experimental test we can devise,” Kaiser says.

    This research was supported in part by the Austrian Academy of Sciences, the Austrian Science Fund, the U.S. National Science Foundation, and the U.S. Department of Energy.

    See the full article here .


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    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

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  • richardmitnick 9:16 am on August 20, 2018 Permalink | Reply
    Tags: , ARC Center of Excellence, , , , , Einstein's equivalence principle, , ,   

    From ARC Centres of Excellence via Science Alert: “We May Soon Know How a Crucial Einstein Principle Works in The Quantum Realm” 

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    From ARC Centres of Excellence

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    Science Alert

    1
    (NiPlot/iStock)

    20 AUG 2018
    MICHELLE STARR

    The puzzle of how Einstein’s equivalence principle plays out in the quantum realm has vexed physicists for decades. Now two researchers may have finally figured out the key that will allow us to solve this mystery.

    Einstein’s physical theories have held up under pretty much every classical physics test thrown at them. But when you get down to the very smallest scales – the quantum realm – things start behaving a little bit oddly.

    The thing is, it’s not really clear how Einstein’s theory of general relativity and quantum mechanics work together. The laws that govern the two realms are incompatible with each other, and attempts to resolve these differences have come up short.

    But the equivalence principle – one of the cornerstones of modern physics – is an important part of general relativity. And if it can be resolved within the quantum realm, that may give us a toehold into resolving general relativity and quantum mechanics.

    The equivalence principle, in simple terms, means that gravity accelerates all objects equally, as can be observed in the famous feather and hammer experiment conducted by Apollo 15 Commander David Scott on the Moon.

    It also means that gravitational mass and inertial mass are equivalent; to put it simply, if you were in a sealed chamber, like an elevator, you would be unable to tell if the force outside the chamber was gravity or acceleration equivalent to gravity. The effect is the same.

    “Einstein’s equivalence principle contends that the total inertial and gravitational mass of any objects are equivalent, meaning all bodies fall in the same way when subject to gravity,” explained physicist Magdalena Zych of the ARC Centre of Excellence for Engineered Quantum Systems in Australia.

    “Physicists have been debating whether the principle applies to quantum particles, so to translate it to the quantum world we needed to find out how quantum particles interact with gravity.

    “We realised that to do this we had to look at the mass.”

    According to relativity, mass is held together by energy. But in quantum mechanics, that gets a bit complicated. A quantum particle can have two different energy states, with different numerical values, known as a superposition.

    And because it has a superposition of energy states, it also has a superposition of inertial masses.

    This means – theoretically, at least – that it should also have a superposition of gravitational masses. But the superposition of quantum particles isn’t accounted for by the equivalence principle.

    “We realised that we had to look how particles in such quantum states of the mass behave in order to understand how a quantum particle sees gravity in general,” Zych said.

    “Our research found that for quantum particles in quantum superpositions of different masses, the principle implies additional restrictions that are not present for classical particles – this hadn’t been discovered before.”

    This discovery allowed the team to re-formulate the equivalence principle to account for the superposition of values in a quantum particle.

    The new formulation hasn’t yet been applied experimentally; but, the researchers said, opens a door to experiments that could test the newly discovered restrictions.

    And it offers a new framework for testing the equivalence principle in the quantum realm – we can hardly wait.

    The team’s research has been published in the journal Nature Physics.

    See the full article here .

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    The objectives for the ARC Centres of Excellence are to:

    undertake highly innovative and potentially transformational research that aims to achieve international standing in the fields of research envisaged and leads to a significant advancement of capabilities and knowledge
    link existing Australian research strengths and build critical mass with new capacity for interdisciplinary, collaborative approaches to address the most challenging and significant research problems
    develope relationships and build new networks with major national and international centres and research programs to help strengthen research, achieve global competitiveness and gain recognition for Australian research
    build Australia’s human capacity in a range of research areas by attracting and retaining, from within Australia and abroad, researchers of high international standing as well as the most promising research students
    provide high-quality postgraduate and postdoctoral training environments for the next generation of researchers
    offer Australian researchers opportunities to work on large-scale problems over long periods of time
    establish Centres that have an impact on the wider community through interaction with higher education institutes, governments, industry and the private and non-profit sector.

     
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