Dark Energy Physicsworld.Com Dark Energy: How the Paradigm Shifted
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Stsci Newsletter: 1997 Volume 014 Issue 01
January 1997 • Volume 14, Number 1 SPACE TELESCOPE SCIENCE INSTITUTE Highlights of this issue: • AURA science and functional awards to Leitherer and Hanisch — pages 1 and 23 • Cycle 7 to be extended — page 5 • Cycle 7 approved Newsletter program listing — pages 7-13 Astronomy with HST Climbing the Starburst Distance Ladder C. Leitherer Massive stars are an important and powerful star formation events in sometimes dominant energy source for galaxies. Even the most luminous star- a galaxy. Their high luminosity, both in forming regions in our Galaxy are tiny light and mechanical energy, makes on a cosmic scale. They are not them detectable up to cosmological dominated by the properties of an distances. Stars ~100 times more entire population but by individual massive than the Sun are one million stars. Therefore stochastic effects times more luminous. Except for stars prevail. Extinction represents a severe of transient brightness, like novae and problem when a reliable census of the supernovae, hot, massive stars are Galactic high-mass star-formation the most luminous stellar objects in history is atempted, especially since the universe. massive stars belong to the extreme Massive stars are, however, Population I, with correspondingly extremely rare: The number of stars small vertical scale heights. Moreover, formed per unit mass interval is the proximity of Galactic regions — roughly proportional to the -2.35 although advantageous for detailed power of mass. We expect to find very studies of individual stars — makes it few massive stars compared to, say, difficult to obtain integrated properties, solar-type stars. This is consistent with such as total emission-line fluxes of observations in our solar neighbor- the ionized gas. -
Cosmology Timeline
Timeline Cosmology • 2nd Millennium BCEBC Mesopotamian cosmology has a flat,circular Earth enclosed in a cosmic Ocean • 12th century BCEC Rigveda has some cosmological hymns, most notably the Nasadiya Sukta • 6th century BCE Anaximander, the first (true) cosmologist - pre-Socratic philosopher from Miletus, Ionia - Nature ruled by natural laws - Apeiron (boundless, infinite, indefinite), that out of which the universe originates • 5th century BCE Plato - Timaeus - dialogue describing the creation of the Universe, - demiurg created the world on the basis of geometric forms (Platonic solids) • 4th century BCE Aristotle - proposes an Earth-centered universe in which the Earth is stationary and the cosmos, is finite in extent but infinite in time • 3rd century BCE Aristarchus of Samos - proposes a heliocentric (sun-centered) Universe, based on his conclusion/determination that the Sun is much larger than Earth - further support in 2nd century BCE by Seleucus of Seleucia • 3rd century BCE Archimedes - book The Sand Reckoner: diameter of cosmos � 2 lightyears - heliocentric Universe not possible • 3rd century BCE Apollonius of Perga - epicycle theory for lunar and planetary motions • 2nd century CE Ptolemaeus - Almagest/Syntaxis: culmination of ancient Graeco-Roman astronomy - Earth-centered Universe, with Sun, Moon and planets revolving on epicyclic orbits around Earth • 5th-13th century CE Aryabhata (India) and Al-Sijzi (Iran) propose that the Earth rotates around its axis. First empirical evidence for Earth’s rotation by Nasir al-Din al-Tusi. • 8th century CE Puranic Hindu cosmology, in which the Universe goes through repeated cycles of creation, destruction and rebirth, with each cycle lasting 4.32 billion years. • • 1543 Nicolaus Copernicus - publishes heliocentric universe in De Revolutionibus Orbium Coelestium - implicit introduction Copernican principle: Earth/Sun is not special • 1609-1632 Galileo Galilei - by means of (telescopic) observations, proves the validity of the heliocentric Universe. -
STARS, PLANETS and GALAXIES 13-18 April Dahlem, Berlin
STARS, PLANETS AND GALAXIES 13-18 April Dahlem, Berlin Friday, 13 April STRUCTURE FORMATION: FROM COSMOLOGICAL TO ISM SCALES 12h15 Drinks and light lunch available 13h15 Guinevere Kauffmann Welcome 13h30 Philippe Andre The Interstellar Medium and Star Formation: Observations. 14h00 Simon White The Origin of the Cosmic Web of Structure on Large Scales 14h30 Oliver Hahn Shocks and Caustics and their importance for galaxy formation 15h00 Eva Grebel Environmental dependence of stellar chemical evolution and dependence on galaxy properties 15h30 COFFEE BREAK 16h00 Daniel Price Star formation and the role of magnetic fields and turbulence 16h30 Thorsten Naab Simulations of Interstellar Medium and Star formation in Galaxies 17h00 Volker Springel Multi-scale, multi-physics simulation methods. 17h30 DISCUSSION (organizer: G. Kauffmann) 18h30 Reception - Dinner at Harnack House ------------------------------------------------------------------------------------------------------------------- Saturday, 14 April DYNAMICAL PROCESSES IN PLANETS, STARS AND GALAXIES 9h00 Sean Andrews Small-Scale Substructures in Protoplanetary Disks 9h30 Ruth Murray-Clay Pebble Accretion in Protoplanetary Disks 10h00 Francoise Combes Dynamical Processes in Galaxies 10h30 Kathryn Johnston Physical Manifestations of Chaos and Regularity Around Galaxies 11h00 COFFEE 11h30 Scott Tremaine Statistical mechanics of self-gravitating N-body systems 12h00 Silvia Toonen Evolution & interaction in stellar binaries and multiples. 12h30 LUNCH FREE AFTERNOON FOR DISCUSSION/RECREATION -
Primack-Phys205-Feb2
Physics 205 6 February 2017 Comparing Observed Galaxies with Simulations Joel R. Primack UCSC Hubble Space Telescope Ultra Deep Field - ACS This picture is beautiful but misleading, since it only shows about 0.5% of the cosmic density. The other 99.5% of the universe is invisible. Matter and Energy Content of the Universe Imagine that the entire universe is an ocean of dark energy. On that ocean sail billions of ghostly ships made of dark matter... Matter and Energy Content of the Dark Universe Matter Ships on a ΛCDM Dark Double Energy Dark Ocean Imagine that the entire universe is an ocean of dark Theory energy. On that ocean sail billions of ghostly ships made of dark matter... Matter Distribution Agrees with Double Dark Theory! Planck Collaboration: Cosmological parameters PlanckPlanck Collaboration: Collaboration: The ThePlanckPlanckmissionmission Planck Collaboration: The Planck mission 6000 6000 Angular scale 5000 90◦ 500018◦ 1◦ 0.2◦ 0.1◦ 0.07◦ Planck Collaboration: The Planck mission European 6000 ] 4000 2 ] 4000 2 K Double K µ [ µ 3000 [ 3000Dark TT Space TT 5000 D D 2000 2000Theory Agency 1000 1000 ] 4000 2 Cosmic 0 K 0 PLANCK 600 Variance600 60 µ 60 [ 3000 300300 30 TT 30 TT 0 0 Satellite D 0 0 D ∆ D Fig. 7. Maximum posterior CMB intensity map at 50 resolution derived from the joint baseline-30 analysis of Planck, WMAP, and ∆ -300 -300 408 MHz observations. A small strip of the Galactic plane, 1.6 % of the sky, is filled in by-30 a constrained realization that has the same statistical properties as the rest of the sky. -
A Model for Core Formation in Dark Matter Haloes and Ultra-Diffuse Galaxies by Outflow Episodes
MNRAS 491, 4523–4542 (2020) doi:10.1093/mnras/stz3306 Advance Access publication 2019 November 26 A model for core formation in dark matter haloes and ultra-diffuse galaxies by outflow episodes Jonathan Freundlich ,1‹ Avishai Dekel,1,2 Fangzhou Jiang ,1 Guy Ishai,1 Nicolas Cornuault,1 Sharon Lapiner,1 Aaron A. Dutton 3 and Andrea V. Maccio` 3,4 1Centre for Astrophysics and Planetary Science, Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel 2Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, CA 95064, USA 3New York University Abu Dhabi, PO Box 129188, Saadiyat Island, Abu Dhabi, United Arab Emirates 4 Max Planck Institute fur¨ Astronomie, Konigstuhl¨ 17, D-69117 Heidelberg, Germany Downloaded from https://academic.oup.com/mnras/article/491/3/4523/5643939 by guest on 24 September 2021 Accepted 2019 November 20. Received 2019 November 20; in original form 2019 July 26 ABSTRACT We present a simple model for the response of a dissipationless spherical system to an instantaneous mass change at its centre, describing the formation of flat cores in dark matter haloes and ultra-diffuse galaxies (UDGs) from feedback-driven outflow episodes in a specific mass range. This model generalizes an earlier simplified analysis of an isolated shell into a system with continuous density, velocity, and potential profiles. The response is divided into an instantaneous change of potential at constant velocities due to a given mass-loss or mass- gain, followed by energy-conserving relaxation to a new Jeans equilibrium. The halo profile is modelled by a two-parameter function with a variable inner slope and an analytic potential profile, which enables determining the associated kinetic energy at equilibrium. -
10. Scientific Programme 10.1
10. SCIENTIFIC PROGRAMME 10.1. OVERVIEW (a) Invited Discourses Plenary Hall B 18:00-19:30 ID1 “The Zoo of Galaxies” Karen Masters, University of Portsmouth, UK Monday, 20 August ID2 “Supernovae, the Accelerating Cosmos, and Dark Energy” Brian Schmidt, ANU, Australia Wednesday, 22 August ID3 “The Herschel View of Star Formation” Philippe André, CEA Saclay, France Wednesday, 29 August ID4 “Past, Present and Future of Chinese Astronomy” Cheng Fang, Nanjing University, China Nanjing Thursday, 30 August (b) Plenary Symposium Review Talks Plenary Hall B (B) 8:30-10:00 Or Rooms 309A+B (3) IAUS 288 Astrophysics from Antarctica John Storey (3) Mon. 20 IAUS 289 The Cosmic Distance Scale: Past, Present and Future Wendy Freedman (3) Mon. 27 IAUS 290 Probing General Relativity using Accreting Black Holes Andy Fabian (B) Wed. 22 IAUS 291 Pulsars are Cool – seriously Scott Ransom (3) Thu. 23 Magnetars: neutron stars with magnetic storms Nanda Rea (3) Thu. 23 Probing Gravitation with Pulsars Michael Kremer (3) Thu. 23 IAUS 292 From Gas to Stars over Cosmic Time Mordacai-Mark Mac Low (B) Tue. 21 IAUS 293 The Kepler Mission: NASA’s ExoEarth Census Natalie Batalha (3) Tue. 28 IAUS 294 The Origin and Evolution of Cosmic Magnetism Bryan Gaensler (B) Wed. 29 IAUS 295 Black Holes in Galaxies John Kormendy (B) Thu. 30 (c) Symposia - Week 1 IAUS 288 Astrophysics from Antartica IAUS 290 Accretion on all scales IAUS 291 Neutron Stars and Pulsars IAUS 292 Molecular gas, Dust, and Star Formation in Galaxies (d) Symposia –Week 2 IAUS 289 Advancing the Physics of Cosmic -
CAMPUS UPDATE Tt fi Matt Dana Priest, Receives Counterterrorism Campaign.” the Prize Includes a $10,000 Pulitzer Prize Award
prisons and other controversial Another UCSC grad, features of the government’s CAMPUS UPDATE tt fi matt Dana Priest, receives counterterrorism campaign.” The prize includes a $10,000 Pulitzer Prize award. ana priest, who visited Priest is the fifth UCSC George Blumenthal named acting chancellor of UC Santa Cruz UC Santa Cruz in graduate to receive a Pulitzer, over that period of D March to accept the following Hector Tobar (1992), time. Acting Chancellor outlines his priorities Division of Social paul schraub paul “George is Sciences’ first respected through- On his fi rst day working in the Offi ce of the Chancellor in Distinguished jon kersey out the university, mid-July, George Blumenthal issued the following statement: Alumni Award, has and he has more even faculty members and 10 graduate teaching assistants received a 2006 than 30 years of who have demonstrated “exemplary and inspiring teaching” Pulitzer Prize. deep working Our primary mission as an institution is to serve the state Shave received top honors from UCSC’s Academic Senate. The Priest, who grad- knowledge of the of California through teaching, research, and public service. 2005–06 Excellence in Teaching Awards were presented by the late uated from UCSC Santa Cruz cam- Therefore, the priorities on which I will focus include: chancellor Denice D. Denton (fourth from right) and Committee on (Merrill College) in pus,” Dynes said. Teaching chair Charles McDowell (far left) at University Center at 1981 with a bache- Blumenthal, 60, R Recruiting and retaining the outstanding faculty, staff, and the end of the academic year. Also pictured are the faculty winners lor’s in politics, has been a mem- students that characterize our campus; (l–r): Ruth Hoffman, Kenneth Pedrotti, Hilde Schwartz, Ana Maria received journalism’s ber of the UCSC Seara, John Isbister, Dean Mathiowetz, and Martin Berger. -
Agenda Order Before Returning to Announcements; No Objection Was Voiced
UNIVERSITY OF CALIFORNIA BERKELEY • DAVIS • IRVINE • LOS ANGELES • MERCED • RIVERSIDE SAN DIEGO • SAN FRANCISCO • SANTA BARBARA • SANTA CRUZ NOTICE OF MEETING REGULAR MEETING OF THE ASSEMBLY OF THE ACADEMIC SENATE Wednesday, May 28, 2003, 10 a.m.-4 p.m. Sunset Village, Covel Commons Grand Horizon Room (Salon A) 300 Deneve Drive University of California, Los Angeles (310) 825-7021 I. ROLL CALL OF MEMBERS 1 II. MINUTES 2 Minutes of the Meeting of March 12, 2003 Appendix A: Assembly Attendance, March 12, 2003 14 III. ANNOUNCEMENTS BY THE PRESIDENT 15 Richard C. Atkinson (Unable to attend. In his stead, Provost and Senior Vice President C. Judson King will participate.) IV. ANNOUNCEMENTS BY THE CHAIR Gayle Binion 15 V. SPECIAL ORDERS (none) VI. REPORTS OF SPECIAL COMMITTEES 15 Report of the Senate’s Task Force on UC Merced Peter Berck, Chair Special meeting of the Assembly: Wednesday, July 20, 2003, UC Berkeley. Next regular meeting of the Assembly: Wednesday, October 29, 2003, UC Berkeley i VII. REPORTS OF STANDING COMMITTEES A. Academic Council Gayle Binion, Chair 1. Nomination and Election of two at-large members to Universitywide Committee on Committees, 2003-2004 (action) 15 2. Assembly Meeting Schedule, 2003-2004 (information) 15 3. Apportionment of Representatives to the Assembly, 2003-2004 (information) 16 4. Proposed Amendments to Senate Bylaws (action) George Blumenthal, Chair, Ad Hoc Committee on Bylaw Revisions 17 5. Proposed Amendments to APM 015 – Faculty Student Relations (action) George Blumenthal, Member, Academic Council 49 6. Proposed Amendments to Academic Personnel Manual (APM) 010 – Academic Freedom (action) Robert Post, Professor of Law 54 7. -
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. -
Matters of Gravity
MATTERS OF GRAVITY The newsletter of the Topical Group on Gravitation of the American Physical Society Number 39 Winter 2012 Contents GGR News: News from NSF, by David Garfinkle ..................... 4 we hear that ..., by David Garfinkle ..................... 4 GGR program at the APS meeting in Atlanta, GA, by David Garfinkle . 5 Research briefs: AdS instability, by David Garfinkle ..................... 7 Conference reports: Isenberg Fest, by Robert M. Wald ...................... 10 COSMO 11, by Carlos Martins ....................... 11 Astro-GR 6 2011, by Sascha Husa et al ................... 14 arXiv:1202.4025v1 [gr-qc] 17 Feb 2012 1 Editor David Garfinkle Department of Physics Oakland University Rochester, MI 48309 Phone: (248) 370-3411 Internet: garfinkl-at-oakland.edu WWW: http://www.oakland.edu/?id=10223&sid=249#garfinkle Associate Editor Greg Comer Department of Physics and Center for Fluids at All Scales, St. Louis University, St. Louis, MO 63103 Phone: (314) 977-8432 Internet: comergl-at-slu.edu WWW: http://www.slu.edu/colleges/AS/physics/profs/comer.html ISSN: 1527-3431 DISCLAIMER: The opinions expressed in the articles of this newsletter represent the views of the authors and are not necessarily the views of APS. The articles in this newsletter are not peer reviewed. 2 Editorial The next newsletter is due September 1st. This and all subsequent issues will be available on the web at https://files.oakland.edu/users/garfinkl/web/mog/ All issues before number 28 are available at http://www.phys.lsu.edu/mog Any ideas for topics that should be covered by the newsletter, should be emailed to me, or Greg Comer, or the relevant correspondent. -
Recent Astronomical Discoveries
From the Atom to the Universe: Recent Astronomical Discoveries Jeremiah P. Ostriker Astronomy starts at the point to which chemistry has brought us: atoms. The basic stuff of which the planets and stars are made is the same as the terres- trial material discussed and analyzed in the ½rst set of essays in this volume. These are the chemical ele - ments, from hydrogen to uranium. Hydrogen, found with oxygen in our plentiful oceanic water, is by far the most abundant element in the universe; iron is the most common of the heavier elements. All the combinations of atoms in the complex chem ical com - pounds studied by chemists on Earth are also pos- sible components of the objects that we see in the cos mos. Although almost all of the regions that we astronomers study are so hot that the more com pli - JEREMIAH P. OSTRIKER, a Fellow cated compounds would be torn apart by the heat, of the American Academy since some surprisingly unstable organic molecules, such as 1975, is the Charles A. Young Pro - cyanopolyynes, have been detected in cold re gions of fes sor Emeritus of Astrophysics at space with very low density of matter. Nev ertheless, Prince ton University and Professor the astronomical world is simpler than the chemical of As tronomy at Columbia Univer - world of the laboratory or the real bio log ical world. sity. His research interests concern dark matter and dark energy, gal - But the enormous spatial and temporal extent of axy formation, and quasars. His the cosmos allows us–and in fact forces us–to ask publications include Heart of Dark - questions that would seem offbeat to a chemist. -
PERSPECTIVES the MAGAZINE of the ASSOCIATION for JEWISH STUDIES in Memory of Jonathan M
The Old and New Media Issue SPRING 2018 FORUM: Old Media, New Media: Librarians and Archivists Reflect PERSPECTIVES THE MAGAZINE OF THE ASSOCIATION FOR JEWISH STUDIES In memory of Jonathan M. Hess MAY 30, 1965–APRIL 9, 2018 Co-editor of AJS InsidePerspectives Cover , Fall 2015–Spring 2018 יהי זכרון ברוך Table of Contents From the Editors 4 From the President 5 From the Executive Director 6 Old and New Media BETWEEN OLD AND NEW MEDIA Old Media, and Older Media 10 David Stern Let There Be Light: The Word of God in the Jewish Tradition, Past, Present, and Future 14 Gabriel Levy Mediating Moses and Matzah 16 Jodi Eichler-Levine What Becomes of Old Media? 20 Jeffrey Shandler New Media in Old Bottles, or Is It the Other Way Around? 26 Ben Schachter CLASSICAL TEXTS IN THE DIGITAL AGE Scroll Down: Classical Jewish Texts on the Internet 28 Gary A. Rendsburg Freedom on the Tablets: Annotation as Media, from Talmudic Scholarship to the Digital Age 36 Itay Marienberg-Milikowsky The Cairo Geniza and Facebook 38 Moshe Yagur and Oded Zinger THE MODERN MEDIASCAPE Jewish Media Power: Myth and Reality 42 Elana Levine and Michael Z. Newman Jewish Selfie-Fashioning: Gender and Religion in the Digital Age 50 Laura Arnold Leibman The Facebook of Life 54 Ira Wagman The Rise of the Militarized Selfie: Notes from Israel 56 Rebecca L. Stein (with Adi Kuntsman) Forum Old Media, New Media: Librarians and Archivists Reflect 60 Read AJS Perspectives Online at associationforjewishstudies.org AJS Perspectives: President Please direct correspondence to: The Magazine of the Christine Hayes Association for Jewish Studies Association for Jewish Studies Yale University Center for Jewish History 15 West 16th Street New York, NY 10011 Editor Vice President / Program Noam Pianko Laura S.