Charles L. Bennett
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Looking at Earth: an Astronaut's Journey Induction Ceremony 2017
american academy of arts & sciences winter 2018 www.amacad.org Bulletin vol. lxxi, no. 2 Induction Ceremony 2017 Class Speakers: Jane Mayer, Ursula Burns, James P. Allison, Heather K. Gerken, and Gerald Chan Annual David M. Rubenstein Lecture Looking at Earth: An Astronaut’s Journey David M. Rubenstein and Kathryn D. Sullivan ALSO: How Are Humans Different from Other Great Apes?–Ajit Varki, Pascal Gagneux, and Fred H. Gage Advancing Higher Education in America–Monica Lozano, Robert J. Birgeneau, Bob Jacobsen, and Michael S. McPherson Redistricting and Representation–Patti B. Saris, Gary King, Jamal Greene, and Moon Duchin noteworthy Select Prizes and Andrea Bertozzi (University of James R. Downing (St. Jude Chil- Barbara Grosz (Harvard Univer- California, Los Angeles) was se- dren’s Research Hospital) was sity) is the recipient of the Life- Awards to Members lected as a 2017 Simons Investi- awarded the 2017 E. Donnall time Achievement Award of the gator by the Simons Foundation. Thomas Lecture and Prize by the Association for Computational American Society of Hematology. Linguistics. Nobel Prize in Chemistry, Clara D. Bloomfield (Ohio State 2017 University) is the recipient of the Carol Dweck (Stanford Univer- Christopher Hacon (University 2017 Robert A. Kyle Award for sity) was awarded the inaugural of Utah) was awarded the Break- Joachim Frank (Columbia Univer- Outstanding Clinician-Scientist, Yidan Prize. through Prize in Mathematics. sity) presented by the Mayo Clinic Di- vision of Hematology. Felton Earls (Harvard Univer- Naomi Halas (Rice University) sity) is the recipient of the 2018 was awarded the 2018 Julius Ed- Nobel Prize in Economic Emmanuel J. -
Cosmology After WMAP (5)
Cosmology After WMAP (5) DavidDavid SpergelSpergel Geneve June 2008 StandardStandard cosmologicalcosmological modelmodel StillStill FitsFits thethe DataData ! General Relativity + Uniform Universe Big Bang " Density of universe determines its fate + shape ! Universe is flat (total density = critical density) " Atoms 4% " Dark Matter 23% " Dark Energy (cosmological constant?) 72% ! Universe has tiny ripples " Adiabatic, scale invariant, Gaussian Fluctuations " Harrison-Zeldovich-Peebles " Inflationary models QuickQuick HistoryHistory ofof thethe UniverseUniverse " Universe starts out hot, dense and filled with radiation " As the universe expands, it cools. • During the first minutes, light elements form • After 500,000 years, atoms form • After 100,000,000 years, stars start to form • After 1 Billion years, galaxies and quasars ThermalThermal HistoryHistory ofof UniverseUniverse radiation matter NEUTRAL r IONIZED 104 103 z GrowthGrowth ofof FluctuationsFluctuations •Linear theory •Basic elements have been understood for 30 years (Peebles, Sunyaev & Zeldovich) •Numerical codes agree at better than 0.1% (Seljak et al. 2003) Sunyaev & Zeldovich CMBCMB OverviewOverview ! We can detect both CMB temperature and polarization fluctuations ! Polarization Fluctuations can be decomposed into E and B modes q ~180/l ADIABATIC DENSITY FLUCTUATIONS ISOCURVATURE ENTROPY FLUCTUATIONS DeterminingDetermining BasicBasic ParametersParameters Baryon Density 2 Wbh = 0.015,0.017..0.031 also measured through D/H DeterminingDetermining BasicBasic ParametersParameters -
Small-Scale Anisotropies of the Cosmic Microwave Background: Experimental and Theoretical Perspectives
Small-Scale Anisotropies of the Cosmic Microwave Background: Experimental and Theoretical Perspectives Eric R. Switzer A DISSERTATION PRESENTED TO THE FACULTY OF PRINCETON UNIVERSITY IN CANDIDACY FOR THE DEGREE OF DOCTOR OF PHILOSOPHY RECOMMENDED FOR ACCEPTANCE BY THE DEPARTMENT OF PHYSICS [Adviser: Lyman Page] November 2008 c Copyright by Eric R. Switzer, 2008. All rights reserved. Abstract In this thesis, we consider both theoretical and experimental aspects of the cosmic microwave background (CMB) anisotropy for ℓ > 500. Part one addresses the process by which the universe first became neutral, its recombination history. The work described here moves closer to achiev- ing the precision needed for upcoming small-scale anisotropy experiments. Part two describes experimental work with the Atacama Cosmology Telescope (ACT), designed to measure these anisotropies, and focuses on its electronics and software, on the site stability, and on calibration and diagnostics. Cosmological recombination occurs when the universe has cooled sufficiently for neutral atomic species to form. The atomic processes in this era determine the evolution of the free electron abundance, which in turn determines the optical depth to Thomson scattering. The Thomson optical depth drops rapidly (cosmologically) as the electrons are captured. The radiation is then decoupled from the matter, and so travels almost unimpeded to us today as the CMB. Studies of the CMB provide a pristine view of this early stage of the universe (at around 300,000 years old), and the statistics of the CMB anisotropy inform a model of the universe which is precise and consistent with cosmological studies of the more recent universe from optical astronomy. -
Understanding Cosmic Acceleration: Connecting Theory and Observation
Understanding Cosmic Acceleration V(!) ! E Hivon Hiranya Peiris Hubble Fellow/ Enrico Fermi Fellow University of Chicago #OMPOSITIONOFAND+ECosmic HistoryY%VENTS$ UR/ INGTHE%CosmicVOLUTIONOFTHE5 MysteryNIVERSE presentpresent energy energy Y density "7totTOT = 1(k=0)K density DAR RADIATION KENER dark energy YDENSIT DARK G (73%) DARKMATTER Y G ENERGY dark matter DARK MA(23.6%)TTER TIONOFENER WHITEWELLUNDERSTOOD DARKNESSPROPORTIONALTOPOORUNDERSTANDING BARYONS BARbaryonsYONS AC (4.4%) FR !42 !33 !22 !16 !12 Fractional Energy Density 10 s 10 s 10 s 10 s 10 s 1 sec 380 kyr 14 Gyr ~1015 GeV SCALEFACTimeTOR ~1 MeV ~0.2 MeV 4IME TS TS TS TS TS TSEC TKYR T'YR Y Y Planck GUT Y T=100 TeV nucleosynthesis Y IES TION TS EOUT DIAL ORS TIONS G TION TION Z T Energy THESIS symmetry (ILC XA 100) MA EN EE WNOF ESTHESIS V IMOR GENERATEOBSERVABLE IT OR ELER ALTHEOR TIONS EF SIGNATURESINTHE#-" EAKSYMMETR EIONIZA INOFR Y% OMBINA R E6 EAKDO #X ONASYMMETR SIC W '54SYMMETR IMELINEOF EFFWR Y Y EC TUR O NUCLEOSYN ), * +E R 4 PLANCKENER Generation BR TR TURBA UC PH Cosmic Microwave NEUTR OUSTICOSCILLA BAR TIONOFPR ER A AC STR of primordial ELEC non-linear growth of P 44 LIMITOFACC Background Emitted perturbations perturbations: GENER ES carries signature of signature on CMB TUR GENERATIONOFGRAVITYWAVES INITIALDENSITYPERTURBATIONS acoustic#-"%MITT oscillationsED NON LINEARSTR andUCTUR EIMPARTS #!0-!0OBSERVES#-" ANDINITIALDENSITYPERTURBATIONS GROWIMPARTINGFLUCTUATIONS CARIESSIGNATUREOFACOUSTIC SIGNATUREON#-"THROUGH *throughEFFWRITESUPANDGR weakADUATES WHICHSEEDSTRUCTUREFORMATION -
From Dark Matter to Galaxies with Convolutional Networks
From Dark Matter to Galaxies with Convolutional Networks Xinyue Zhang*, Yanfang Wang*, Wei Zhang*, Siyu He Yueqiu Sun*∗ Department of Physics, Carnegie Mellon University Center for Data Science, New York University Center for Computational Astrophysics, Flatiron Institute xz2139,yw1007,wz1218,[email protected] [email protected] Gabriella Contardo, Francisco Shirley Ho Villaescusa-Navarro Center for Computational Astrophysics, Flatiron Institute Center for Computational Astrophysics, Flatiron Institute Department of Astrophysical Sciences, Princeton gcontardo,[email protected] University Department of Physics, Carnegie Mellon University [email protected] ABSTRACT 1 INTRODUCTION Cosmological surveys aim at answering fundamental questions Cosmology focuses on studying the origin and evolution of our about our Universe, including the nature of dark matter or the rea- Universe, from the Big Bang to today and its future. One of the holy son of unexpected accelerated expansion of the Universe. In order grails of cosmology is to understand and define the physical rules to answer these questions, two important ingredients are needed: and parameters that led to our actual Universe. Astronomers survey 1) data from observations and 2) a theoretical model that allows fast large volumes of the Universe [10, 12, 17, 32] and employ a large comparison between observation and theory. Most of the cosmolog- ensemble of computer simulations to compare with the observed ical surveys observe galaxies, which are very difficult to model theo- data in order to extract the full information of our own Universe. retically due to the complicated physics involved in their formation The constant improvement of computational power has allowed and evolution; modeling realistic galaxies over cosmological vol- cosmologists to pursue elucidating the fundamental parameters umes requires running computationally expensive hydrodynamic and laws of the Universe by relying on simulations as their theory simulations that can cost millions of CPU hours. -
Dark Matter Search with the Newsdm Experiment Using Machine Learning Techniques
UNIVERSITÀ DEGLI STUDI DI NAPOLI “FEDERICO II” Scuola Politecnica e delle Scienze di Base Area Didattica di Scienze Matematiche Fisiche e Naturali Dipartimento di Fisica “Ettore Pancini” Laurea Magistrale in Fisica Dark Matter search with the NEWSdm experiment using machine learning techniques Relatori: Candidato: Prof. Giovanni De Lellis Chiara Errico Dott.ssa Antonia Di Crescenzo Matricola N94/457 Dott. Andrey Alexandrov Anno Accademico 2018/2019 Acting with love brings huge happening · Contents Introduction1 1 Dark matter: first evidences and detection3 1.1 First evidences of dark matter.................3 1.2 WIMPs..............................8 1.3 Search for dark matter...................... 11 1.4 Direct detection.......................... 13 1.5 Detectors for direct search.................... 15 1.5.1 Bolometers........................ 16 1.5.2 Liquid noble-gas detector................. 17 1.5.3 Scintillator......................... 18 1.6 Direct detection experiment general result........... 20 1.7 Directionality........................... 21 1.7.1 Nuclear Emulsion..................... 23 2 The NEWSdm experiment 25 2.1 Nano Imaging Trackers...................... 25 2.2 Layout of the NEWSdm detector................ 28 2.2.1 Technical test....................... 29 2.3 Expected background....................... 30 2.3.1 External background................... 31 2.3.2 Intrinsic background................... 34 2.3.3 Instrumental background................. 35 2.4 Optical microscope........................ 35 2.4.1 Super-resolution microscope for dark matter search.. 38 2.5 Candidate Selection........................ 40 2.6 Candidate Validation....................... 42 iii Contents iv 3 Reconstruction of nanometric tracks 47 3.1 Scanning process......................... 47 3.2 Analysis of NIT exposed to Carbon ions............ 49 3.3 Shape analysis........................... 50 3.4 Plasmon analysis......................... 51 3.4.1 Accuracy.......................... 52 3.4.2 Npeaks.......................... -
Lars Hernquist and Volker Springel Receive $500,000 Gruber Cosmology Prize
Media Contact: A. Sarah Hreha +1 (203) 432‐6231 [email protected] Online Newsroom: https://gruber.yale.edu/news‐media Lars Hernquist and Volker Springel Receive $500,000 Gruber Cosmology Prize Lars Hernquist Volker Springel New Haven, CT — The 2020 Gruber Cosmology Prize recognizes Lars Hernquist, Center for Astrophysics | Harvard & Smithsonian, and Volker Springel, Max Planck Institute for Astrophysics, for their defining contributions to cosmological simulations, a method that tests existing theories of, and inspires new investigations into, the formation of structures at every scale from stars to galaxies to the universe itself. Hernquist and Springel will divide the $500,000 award, and each will receive a gold laureate pin at a ceremony that will take place later this year. The award recognizes their transformative work on structure formation in the universe, and development of numerical algorithms and community codes further used by many other researchers to significantly advance the field. Hernquist was a pioneer in cosmological simulations when he joined the fledgling field in the late 1980s, and since then he has become one of its most influential figures. Springel, who entered the field in 1998 and first partnered with Hernquist in the early 2000s, has written and applied several of the most widely used codes in cosmological research. Together Hernquist and Springel constitute, in the words of one Gruber Prize nominator, “one of the most productive collaborations ever in cosmology.” Computational simulations in cosmology begin with the traditional source of astronomical data: observations of the universe. Then, through a combination of theory and known physics that might approximate initial conditions, the simulations recreate the subsequent processes that would have led to the current structure. -
1St Edition of Brown Physics Imagine, 2017-2018
A note from the chair... "Fellow Travelers" Ladd Observatory.......................11 Sci-Toons....................................12 Faculty News.................. 15-16, 23 At-A-Glance................................18 s the current academic year draws to an end, I’m happy to report that the Physics Department has had Newton's Apple Tree................. 23 an exciting and productive year. At this year's Commencement, the department awarded thirty five "Untagling the Fabric of the undergraduate degrees (ScB and AB), twenty two Master’s degrees, and ten Ph.D. degrees. It is always Agratifying for me to congratulate our graduates and meet their families at the graduation ceremony. This Universe," Professor Jim Gates..26 Alumni News............................. 27 year, the University also awarded my colleague, Professor J. Michael Kosterlitz, an honorary degree for his Events this year......................... 28 achievement in the research of low-dimensional phase transitions. Well deserved, Michael! Remembering Charles Elbaum, Our faculty and students continue to generate cutting-edge scholarships. Some of their exciting Professor Emeritus.................... 29 research are highlighted in this magazine and have been published in high impact journals. I encourage you to learn about these and future works by watching the department YouTube channel or reading faculty’s original publications. Because of their excellent work, many of our undergraduate and graduate students have received students prestigious awards both from Brown and externally. As Chair, I feel proud every time I hear good news from our On the cover: PhD student Shayan Lame students, ranging from receiving the NSF Graduate Fellowship to a successful defense of thier senior thesis or a Class of 2018............................. -
Searches for Heavy Vector-Like Quarks Decaying to High Transverse
Searches for heavy vector-like quarks decaying to high transverse momentum W bosons and top- or bottom-quarks and weak mode identification with the ATLAS detector by Steffen Henkelmann B.Sc., The University of Göttingen, 2011 M.Sc., The University of Göttingen, 2013 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in The Faculty of Graduate and Postdoctoral Studies (Physics) THE UNIVERSITY OF BRITISH COLUMBIA CERN-THESIS-2018-212 29/06/2018 (Vancouver) August 2018 c Steffen Henkelmann 2018 The following individuals certify that they have read, and recommend to the Faculty of Gradu- ate and Postdoctoral Studies for acceptance, the dissertation entitled: Searches for heavy vector-like quarks decaying to high transverse momentum W bosons and top- or bottom-quarks and weak mode identification with the ATLAS detector submitted by Steffen Henkelmann in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Physics Examining committee: Alison Lister, Physics & Astronomy Supervisor Colin Gay, Physics & Astronomy Supervisory Committee Member Gary Hinshaw, Physics & Astronomy Supervisory Committee Member David Morrissey, TRIUMF Supervisory Committee Member Janis McKenna, Physics & Astronomy University Examiner Donald Fleming, Chemistry University Examiner ii Abstract The precise understanding of elementary particle properties and theory parameters predicted by the Standard Model of Particle Physics (SM) as well as the revelation of new physics phe- nomena beyond the scope of that successful theory are at the heart of modern fundamental particle physics research. The Large Hadron Collider (LHC) and modern particle detectors pro- vide the key to probing nature at energy scales never achieved in an experimental controlled setup before. -
Report for the Academic Year 1999
l'gEgasag^a3;•*a^oggMaBgaBK>ry^vg^.g^._--r^J3^JBgig^^gqt«a»J^:^^^^^ Institute /or ADVANCED STUDY REPORT FOR THE ACADEMIC YEAR 1998-99 PRINCETON • NEW JERSEY HISTORICAL STUDIES^SOCIAl SC^JCE LIBRARY INSTITUTE FOR ADVANCED STUDY PRINCETON, NEW JERSEY 08540 Institute /or ADVANCED STUDY REPORT FOR THE ACADEMIC YEAR 1 998 - 99 OLDEN LANE PRINCETON • NEW JERSEY • 08540-0631 609-734-8000 609-924-8399 (Fax) http://www.ias.edu Extract from the letter addressed by the Institute's Founders, Louis Bamberger and Mrs. FeUx Fuld, to the Board of Trustees, dated June 4, 1930. Newark, New Jersey. It is fundamental m our purpose, and our express desire, that in the appointments to the staff and faculty, as well as in the admission of workers and students, no account shall be taken, directly or indirectly, of race, religion, or sex. We feel strongly that the spirit characteristic of America at its noblest, above all the pursuit of higher learning, cannot admit of any conditions as to personnel other than those designed to promote the objects for which this institution is established, and particularly with no regard whatever to accidents of race, creed, or sex. ni' TABLE OF CONTENTS 4 • BACKGROUND AND PURPOSE 7 • FOUNDERS, TRUSTEES AND OFFICERS OF THE BOARD AND OF THE CORPORATION 10 • ADMINISTRATION 12 • PRESENT AND PAST DIRECTORS AND FACULTY 15 REPORT OF THE CHAIRMAN 18 • REPORT OF THE DIRECTOR 22 • OFFICE OF THE DIRECTOR - RECORD OF EVENTS 27 ACKNOWLEDGMENTS 41 • REPORT OF THE SCHOOL OF HISTORICAL STUDIES FACULTY ACADEMIC ACTIVITIES MEMBERS, VISITORS, -
Astro2020 Science White Paper Primordial Non-Gaussianity
Astro2020 Science White Paper Primordial Non-Gaussianity Thematic Areas: Cosmology and Fundamental Physics Principal Author: Name: P. Daniel Meerburg Institution: University of Cambridge Email: [email protected] Abstract: Our current understanding of the Universe is established through the pristine measurements of structure in the cosmic microwave background (CMB) and the distribution and shapes of galaxies tracing the large scale structure (LSS) of the Universe. One key ingredient that underlies cosmological observables is that the field that sources the observed structure is assumed to be initially Gaussian with high precision. Nevertheless, a minimal deviation from Gaussianity is perhaps the most robust theoretical prediction of models that explain the observed Universe; it is necessarily present even in the simplest scenarios. In addition, most inflationary models produce far higher levels of non-Gaussianity. Since non-Gaussianity directly probes the dynamics in the early Universe, a detection would present a monumental discovery in cosmology, providing clues about physics at energy scales as high as the GUT scale. This white paper aims to motivate a continued search to obtain evidence for deviations from Gaussianity in the primordial Universe. Since the previous decadal, important advances have been made, both theoretically and observationally, which have further established the importance of deviations from Gaussianity in cosmology. Foremost, primordial non-Gaussianities are now very tightly constrained by the CMB. Second, models motivated by stringy physics suggest detectable signatures of primordial non-Gaussianities with a unique shape which has not been considered in previous searches. Third, improving constraints using LSS requires a better understanding how to disentangle non-Gaussianities sourced at late times from those sourced by the physics in the early Universe. -
Looking at Earth: an Astronaut's Journey Induction Ceremony 2017
american academy of arts & sciences winter 2018 www.amacad.org Bulletin vol. lxxi, no. 2 Induction Ceremony 2017 Class Speakers: Jane Mayer, Ursula Burns, James P. Allison, Heather K. Gerken, and Gerald Chan Annual David M. Rubenstein Lecture Looking at Earth: An Astronaut’s Journey David M. Rubenstein and Kathryn D. Sullivan ALSO: How Are Humans Different from Other Great Apes?–Ajit Varki, Pascal Gagneux, and Fred H. Gage Advancing Higher Education in America–Monica Lozano, Robert J. Birgeneau, Bob Jacobsen, and Michael S. McPherson Redistricting and Representation–Patti B. Saris, Gary King, Jamal Greene, and Moon Duchin Upcoming Events MARCH APRIL 1st 12th California Institute of Technology American Academy Pasadena, CA Cambridge, MA Bryson Symposium on Climate and Annual Awards Ceremony: A Celebration of the Energy Policy Arts and Sciences Featuring: Dallas Burtraw (Resources for Featuring: Martha C. Nussbaum (Univer- the Future), Ralph Cavanagh (nrdc), sity of Chicago), recipient of the Don M. Nathan S. Lewis (California Institute of Randel Award for Humanistic Studies; and Technology), Mary Nichols (California Barbara J. Meyer (University of California, Air Resources Board), Ronald O. Nichols Berkeley), recipient of the Francis Amory (Southern California Edison), Thomas F. Prize in Medicine & Physiology Rosenbaum (California Institute of Tech- nology), and Maxine L. Savitz (Honeywell, MAY Inc., ret.; formerly, President’s Council of Advisors on Science and Technology) 3rd American Academy 7th Cambridge, MA American Academy Songs of Love and Death: Sonnets by Petrarch Cambridge, MA and Others Set by Cipriano de Rore in “I madri- Building, Exploring, and Using the Tree of Life gali a cinque voci” (Venice, 1542) Featuring: Douglas E.