DAP January 2018 Newsletter
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A Time of Great Growth
Newsletter | Spring 2019 A Time of Great Growth Heartfelt greetings from the UC Riverside Department of Physics and Astronomy. This is our annual newsletter, sent out each Spring to stay connected with our former students, retired faculty, and friends in the wider community. The Department continues to grow, not merely in size but also in stature and reputation. For the 2018-2019 academic year, we were pleased to welcome two new faculty: Professors Thomas Kuhlman and Barry Barish. Professor Kuhlman was previously on the faculty at the University of Illinois at Urbana-Champaign. He joins our efforts in the emerging field of biophysics. His research lies in the quantitative imaging and theoretical modeling of biological systems. He works on genome dynamics, quantification of the activity of transposable elements in living cells, and applications to the engineering of genome editing. Professor Barry Barish, who joins us from Caltech, is the winner of the 2017 Nobel Prize in Physics. He brings great prestige to our Department. Along with Professor Richard Schrock of the Department of Chemistry, who also joined UCR in 2018, UCR now has two Nobel Prize winners on its faculty. Professor Barish is an expert on the detection and physics of gravitational waves. He has been one of the key figures in the conception, construction, and operation of the LIGO detector, where gravitational waves were first discovered in 2015, and which led to his Nobel Prize. He is a member of the National Academy of Sciences and the winner of many other prestigious awards. The discovery of gravitational waves is one of the most exciting developments in physics so far this century. -
Ripples in Spacetime
editorial Ripples in spacetime The 2017 Nobel prize in Physics has been awarded to Rainer Weiss, Barry C. Barish and Kip S. Thorne “for decisive contributions to the LIGO detector and the observation of gravitational waves”. It is, frankly, difficult to find something original to say about the detection of gravitational waves that hasn’t been said already. The technological feat of measuring fluctuations in the fabric of spacetime less than one-thousandth the width of an atomic nucleus is quite simply astonishing. The scientific achievement represented by the confirmation of a century-old prediction by Albert Einstein is unique. And the collaborative effort that made the discovery possible — the Laser Interferometer Gravitational-Wave Observatory (LIGO) — is inspiring. Adapted from Phys. Rev. Lett. 116, 061102 (2016), under Creative Commons Licence. Rainer Weiss and Kip Thorne were, along with the late Ronald Drever, founders of the project that eventually became known Barry Barish, who was the director Last month we received a spectacular as LIGO. In the 1960s, Thorne, a black hole of LIGO from 1997 to 2005, is widely demonstration that talk of a new era expert, had come to believe that his objects of credited with transforming it into a ‘big of gravitational astronomy was no interest should be detectable as gravitational physics’ collaboration, and providing the exaggeration. Cued by detections at LIGO waves. Separately, and inspired by previous organizational structure required to ensure and Virgo, an interferometer based in Pisa, proposals, Weiss came up with the first it worked. Of course, the passion, skill and Italy, more than 70 teams of researchers calculations detailing how an interferometer dedication of the thousand or so scientists working at different telescopes around could be used to detect them in 1972. -
The History of Lasers at Stanford Group
Lasers at 50: Byer The History of Lasers at Stanford Group Robert L. Byer Applied Physics Stanford University [email protected] Abstract In the fifty years since the demonstration of the laser, coherent light has changed the way we work, communicate and play. The generation and control of light is critical for meeting important challenges of the 21st century from fundamental science to the generation of energy. A look back at the early days of the laser at Stanford will be contrasted to the recent breakthroughs in solid state lasers and the applications to fundamental science of gravitational wave detection, remote sensing, and laser induced fusion for energy production. Stanford Historical Society 34th Annual Meeting & Reception May 25, 2010 The History of Lasers at Stanford May 25 2010 Cubberley Auditorium, Staford Byer California – Leader in advanced telescopes for astronomy Group Lick 36 inch refractor The Mount Wilson 100 inch The Palomar 200 inch 1888 1917 1948 The History of Lasers at Stanford May 25 2010 Cubberley Auditorium, Staford From Maser to Laser – stimulated emission at optical frequencies Byer proposed in 1958 – A. Schawlow and C. H. Townes Group The History of Lasers at Stanford May 25 2010 Cubberley Auditorium, Staford Early advances in lasers --- Byer 2009 a Special Year Group Concept of Optical Maser Schawlow & Townes 1958 Ruby Laser Ted Maiman 1960 Nobel Prize awarded in 1964 Townes, Prokhorov and Basov Hg+ Ion Laser Earl Bell 1965 Argon Ion Laser Bill Bridges Tunable cw parametric Laser Harris 1968 Diode bar 1Watt -
David Kirkby University of California, Irvine, USA 4 August 2020 Expanding Universe
COSMOLOGY IN THE 2020S David Kirkby University of California, Irvine, USA 4 August 2020 Expanding Universe... 2 expansion history a(t |Ωm, ΩDE, …) 3 4 redshift 5 6 0.38Myr opaque universe last scatter 7 inflation opaque universe last scatter gravity waves? 8 CHIME SPT-3G DES 9 TCMB=2.7K, λ~2mm 10 CMB TCMB=2.7K, λ~2mm Galaxies 11 microwave projects: cosmic microwave background (primordial gravity waves, neutrinos, ...) CMB Galaxies optical & NIR projects: galaxy surveys (dark energy, neutrinos, ...) 12 CMB Galaxies telescope location: ground / above atmosphere 13 CMB Atacama desert, Chile CMB ground telescope location: Atacama desert / South Pole 14 Galaxies Galaxy survey instrument: spectrograph / imager 15 Dark Energy Spectroscopic Instrument (DESI) Vera Rubin Observatory 16 Dark Energy Spectroscopic Instrument (DESI) Vera Rubin Observatory 17 EXPANSION HISTORY VS STRUCTURE GROWTH Measurements of our cosmic expansion history constrain the parameters of an expanding homogenous universe: SN LSS , …) expansion historyDE m, Ω a(t |Ω CMB Small inhomogeneities are growing against this backdrop. Measurements of this structure growth provide complementary constraints. 18 Structure Growth 19 Redshift is not a perfect proxy for distance because of galaxy peculiar motions. Large-scale redshift-space distortions (RSD) trace large-scale matter fluctuations: signal! 20 Angles measured on the sky are also distorted by weak lensing (WL) as light is deflected by the same large-scale matter fluctuations: signal! Large-scale redshift-space distortions (RSD) trace large-scale matter fluctuations: signal! 21 CMB measures initial conditions of structure growth at z~1090: Temperature CMB photons also experience weak lensing! https://wiki.cosmos.esa.int/planck-legacy-archive/index.php/CMB_maps Polarization 22 CMB: INFLATION ERA SIGNATURES https://www.annualreviews.org/doi/abs/10.1146/annurev-astro-081915-023433 lensing E-modes lensing B-modes GW B-modes https://arxiv.org/abs/1907.04473 Lensing B modes already observed. -
Rainer Weiss, Professor of Physics Emeritus and 2017 Nobel Laureate
Giving to the Department of Physics by Erin McGrath RAINER WEISS ’55, PHD ’62 Bryce Vickmark Rai Weiss has established a fellowship in the Physics Department because he is eternally grateful to his advisor, the late Jerrold Zacharias, for all that he did for Rai, so he knows firsthand the importance of supporting graduate students. Rainer Weiss, Professor of Physics Emeritus and 2017 Nobel Laureate. Rainer “Rai” Weiss was born in Berlin, Germany in 1932. His father was a physician and his mother was an actress. His family was forced out of Germany by the Nazis since his father was Jewish and a Communist. Rai, his mother and father fled to Prague, Czecho- slovakia. In 1937 a sister was born in Prague. In 1938, after Chamberlain appeased Hitler by effectively giving him Czechoslovakia, the family was able to obtain visas to enter the United States through the Stix Family in St. Louis, who were giving bond to professional Jewish emigrants. When Rai was 21 years-old, he visited Mrs. Stix and thanked her for what she had done for his family. The family immigrated to New York City. Rai’s father had a hard time passing the medi- cal boards because of his inability to answer multiple choice exams. His mother, who Rai says “held the family together,” worked in a number of retail stores. Through the services of an immigrant relief organization Rai received a scholarship to attend the prestigious Columbia Grammar School. At the end of 1945, when Rai was 13 years old, he became fascinated with electronics and music. -
A New Universe to Discover: a Guide to Careers in Astronomy
A New Universe to Discover A Guide to Careers in Astronomy Published by The American Astronomical Society What are Astronomy and Astrophysics? Ever since Galileo first turned his new-fangled one-inch “spyglass” on the moon in 1609, the popular image of the astronomer has been someone who peers through a telescope at the night sky. But astronomers virtually never put eye to lens these days. The main source of astronomical data is still photons (particles of light) from space, but the tools used to gather and analyze them are now so sophisticated that it’s no longer necessary (or even possible, in most cases) for a human eye to look through them. But for all the high-tech gadgetry, the 21st-Century astronomer is still trying to answer the same fundamental questions that puzzled Galileo: How does the universe work, and where did it come from? Webster’s dictionary defines “astronomy” as “the science that deals with the material universe beyond the earth’s atmosphere.” This definition is broad enough to include great theoretical physicists like Isaac Newton, Albert Einstein, and Stephen Hawking as well as astronomers like Copernicus, Johanes Kepler, Fred Hoyle, Edwin Hubble, Carl Sagan, Vera Rubin, and Margaret Burbidge. In fact, the words “astronomy” and “astrophysics” are pretty much interchangeable these days. Whatever you call them, astronomers seek the answers to many fascinating and fundamental questions. Among them: *Is there life beyond earth? *How did the sun and the planets form? *How old are the stars? *What exactly are dark matter and dark energy? *How did the Universe begin, and how will it end? Astronomy is a physical (non-biological) science, like physics and chemistry. -
What Happened Before the Big Bang?
Quarks and the Cosmos ICHEP Public Lecture II Seoul, Korea 10 July 2018 Michael S. Turner Kavli Institute for Cosmological Physics University of Chicago 100 years of General Relativity 90 years of Big Bang 50 years of Hot Big Bang 40 years of Quarks & Cosmos deep connections between the very big & the very small 100 years of QM & atoms 50 years of the “Standard Model” The Universe is very big (billions and billions of everything) and often beyond the reach of our minds and instruments Big ideas and powerful instruments have enabled revolutionary progress a very big idea connections between quarks & the cosmos big telescopes on the ground Hawaii Chile and in space: Hubble, Spitzer, Chandra, and Fermi at the South Pole basics of our Universe • 100 billion galaxies • each lit with the light of 100 billion stars • carried away from each other by expanding space from a • big bang beginning 14 billion yrs ago Hubble (1925): nebulae are “island Universes” Universe comprised of billions of galaxies Hubble Deep Field: one ten millionth of the sky, 10,000 galaxies 100 billion galaxies in the observable Universe Universe is expanding and had a beginning … Hubble, 1929 Signature of big bang beginning Einstein: Big Bang = explosion of space with galaxies carried along The big questions circa 1978 just two numbers: H0 and q0 Allan Sandage, Hubble’s “student” H0: expansion rate (slope age) q0: deceleration (“droopiness” destiny) … tens of astronomers working (alone) to figure it all out Microwave echo of the big bang Hot MichaelBig S Turner Bang -
Electronic Newsletter December 15, 2016
Electronic Newsletter December 15, 2016 In this issue • April Meeting (in January) Washington, DC • DAP Nominations • APS Fellows from DAP • 2017 Bethe Prize • April Meeting Overview • DAP Awards Ceremony • Public Lecture and Plenary Session Highlights • DAP Session Schedule • Focus Sessions sponsored by the DAP • Invited Session Highlights APS DAP Officers 2016–2017: Finalize your plans now to attend the April 2017 meeting held Chair: Julie McEnery this year in January in Washington, DC. A number of plenary and invited sessions will feature presentations by DAP mem- Chair-Elect: Fiona Harrison bers. Here are the key details: Vice Chair: Priyamvada Natarajan Past Chair: Paul Shapiro What: April 2017 APS Meeting Secretary/Treasurer: Scott Dodelson When: Saturday, Jan 28 – Tuesday, Jan 31, 2016 Deputy Sec./Treasurer: Where: Washington, DC (Marriott Wardman Park) Keivan Stassun Member-at-Large: Registration Deadline: January 6, 2017 Brenna Flaugher Division Councilor: The 2017 April Meeting will take place at the Marriott Ward- Miriam Forman man Park. Detailed information for the meeting, including details Member-at-Large: on registration and the scientific program can be found online at Daniel Kasen http://www.aps.org/meetings/april Member-at-Large: Marc Kamionkowski Note that you can still register on-site, if you don’t do so by the Member-at-Large: deadline. Tracy Slatyer Registration fees range from $30 for undergraduates to $480 for full members. Questions? Comments? Newsletter Editor: Keivan Stassun [email protected] Nominations for the APS DAP Executive Committee Officers Deadline: December 21, 2016 Each year the Division of Astrophysics (DAP) of the APS elects new members for the open positions on the DAP Executive Committee. -
A Joint Fermilab/SLAC Publication Dimensions of Particle Physics Issue
dimensions volume 03 of particle physics symmetryA joint Fermilab/SLAC publication issue 05 june/july 06 Cover Physicists at Fermilab ponder the physics of the proposed International Linear Collider, as outlined in the report Discovering the Quantum Universe. Photos: Reidar Hahn, Fermilab Office of Science U.S. Department of Energy volume 03 | issue 05 | june/july 06 symmetryA joint Fermilab/SLAC publication 3 Commentary: John Beacom “In a global fi eld, keeping up with all the literature is impossible. Personal contact is essential, and I always urge students and postdocs to go to meetings and talk to strangers.” 4 Signal to Background An industrial waterfall; education by placemats; a super-clean surface; horned owls; Garden Club for particle physicists; Nobel banners; US Congress meets Quantum Universe. 8 Voices: Milestones vs. History Celebrating a milestone is always enjoyable, but a complete and accurate historical record is invalu- able for the past to inform the future. 10 A Report Like No Other Can the unique EPP2010 panel steer US particle physics away from a looming crisis? Physicists and policy makers are depending on it. 14 SNS: Neutrons for ‘molecular movies’ A new research facility at Oak Ridge National Laboratory has produced its fi rst neutrons, presenting new opportunities for studying materials from semiconductors to human enzymes. 20 Battling the Clouds Electron clouds could reduce the brightness—and discovery potential—of the proposed International Linear Collider. Innovative solutions are on the way and might reduce the cost of the machine, too. 24 A (Magnus) Force on the Mound Professional baseball player Jeff Francis of the Colorado Rockies brings a strong arm and a physics background to the playing fi eld: “I bet Einstein couldn’t throw a curveball.” 26 Deconstruction: Spallation Neutron Source Accelerator-based neutron sources such as the SNS can provide pulses of neutrons to probe superconductors, aluminum bridges, lighter and stronger plastic products, and pharmaceuticals. -
The Strong and Weak Senses of Theory-Ladenness of Experimentation: Theory-Driven Versus Exploratory Experiments in the History of High-Energy Particle Physics
[Accepted for Publication in Science in Context] The Strong and Weak Senses of Theory-Ladenness of Experimentation: Theory-Driven versus Exploratory Experiments in the History of High-Energy Particle Physics Koray Karaca University of Wuppertal Interdisciplinary Centre for Science and Technology Studies (IZWT) University of Wuppertal Gaußstr. 20 42119 Wuppertal, Germany [email protected] Argument In the theory-dominated view of scientific experimentation, all relations of theory and experiment are taken on a par; namely, that experiments are performed solely to ascertain the conclusions of scientific theories. As a result, different aspects of experimentation and of the relation of theory to experiment remain undifferentiated. This in turn fosters a notion of theory- ladenness of experimentation (TLE) that is too coarse-grained to accurately describe the relations of theory and experiment in scientific practice. By contrast, in this article, I suggest that TLE should be understood as an umbrella concept that has different senses. To this end, I introduce a three-fold distinction among the theories of high-energy particle physics (HEP) as background theories, model theories and phenomenological models. Drawing on this categorization, I contrast two types of experimentation, namely, “theory-driven” and “exploratory” experiments, and I distinguish between the “weak” and “strong” senses of TLE in the context of scattering experiments from the history of HEP. This distinction enables to identify the exploratory character of the deep-inelastic electron-proton scattering experiments— performed at the Stanford Linear Accelerator Center (SLAC) between the years 1967 and 1973—thereby shedding light on a crucial phase of the history of HEP, namely, the discovery of “scaling”, which was the decisive step towards the construction of quantum chromo-dynamics (QCD) as a gauge theory of strong interactions. -
Members Elect Barry Barish As Next APS Vice-President
October 2008 Volume 17, No. 9 www.aps.org/publications/apsnews 21st Century Campaign Nears Goal APS NEWS and Needs Your Support! A PublicAtion of the AmericAn PhysicAl society • www.APs.org/PublicAtions/APsnews (See insert) Energy Efficiency Crucial to Achieving Energy Security Members Elect Barry Barish and Reducing Global Warming, States APS Report as next APS Vice-President Tapping wasted energy from miles per gallon mileage for cars needs because they require sig- APS members have elected in physics from the University of inefficient automobiles, homes and and other light-duty vehicles by nificant scientific and engineering Barry Barish, Linde Professor of California, Berkeley. He joined businesses is equivalent to discov- 2030 and the elimination of energy breakthroughs in several critical Physics Emeritus at Caltech, as the faculty at Caltech in 1963. ering a hidden energy reserve that from fossil fuels in new residential areas. the Society’s next vice president. Among his noteworthy experi- will help the United States improve buildings by 2020. The study also calls on Congress Barish will assume the office in ments were those performed at its energy security and reduce glob- and the White House to increase January 2009. At the same time, Fermilab using high-energy neu- al warming, an APS study panel has spending on research and develop- Curtis Callan of trino collisions to concluded. ment of next-generation building Princeton Univer- reveal the quark Their report, Energy Future: technologies, training scientists sity will become substructure of Think Efficiency, states that the key who work on building technologies president-elect, and the nucleon. -
Beyond Einstein
QuarksQuarks toto thethe Cosmos:Cosmos: the deep connections between the largest and smallest scales in the Universe ScalesScales ofof thethe UniverseUniverse LectureLecture SeriesSeries 16 November 2007 Michael S. Turner Kavli Institute for Cosmological Physics The UniversityMichael S Turner of Chicago Full Scale Model of Universe a Fraction of a Second After the Beginning Amazing as it is, the connections go far beyond the fact that it began as Quark Soup NB: No deep connections between quarks and chemistry even though are made of quarks! ••TheThe AtomsAtoms wewe andand thethe starsstars ofof mademade ofof ••TheThe DarkDark MatterMatter thatthat holdsholds thethe UniverseUniverse togethertogether ••TheThe DarkDark EnergyEnergy thatthat isis causingcausing thethe expansionexpansion ofof thethe UniverseUniverse toto speedspeed upup ••TheThe SeedsSeeds ofof allall structuresstructures (clusters,(clusters, galaxies,galaxies, stars,stars, ……)) TheThe UniverseUniverse isis gettinggetting biggerbigger –– expandingexpanding ExpandingExpanding UniverseUniverse isis expandingexpanding spacespace • Hubble’s law (correlation between velocity and distance) • Redshift of light • General relativity NoNo CenterCenter JustJust DifferentDifferent PerspectivesPerspectives EvidenceEvidence forfor HotHot BigBig BangBang • Expansion of Universe • Cosmic microwave background: microwave echo of big bang • Abundance of the elements H, D, He, Li • Consistent age: expansion age, oldest stars, age of radioactive elements, cooling of white dwarf stars, age of oldest