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Is the Universe Expanding?: an Historical and Philosophical Perspective for Cosmologists Starting Anew
Western Michigan University ScholarWorks at WMU Master's Theses Graduate College 6-1996 Is the Universe Expanding?: An Historical and Philosophical Perspective for Cosmologists Starting Anew David A. Vlosak Follow this and additional works at: https://scholarworks.wmich.edu/masters_theses Part of the Cosmology, Relativity, and Gravity Commons Recommended Citation Vlosak, David A., "Is the Universe Expanding?: An Historical and Philosophical Perspective for Cosmologists Starting Anew" (1996). Master's Theses. 3474. https://scholarworks.wmich.edu/masters_theses/3474 This Masters Thesis-Open Access is brought to you for free and open access by the Graduate College at ScholarWorks at WMU. It has been accepted for inclusion in Master's Theses by an authorized administrator of ScholarWorks at WMU. For more information, please contact [email protected]. IS THEUN IVERSE EXPANDING?: AN HISTORICAL AND PHILOSOPHICAL PERSPECTIVE FOR COSMOLOGISTS STAR TING ANEW by David A Vlasak A Thesis Submitted to the Faculty of The Graduate College in partial fulfillment of the requirements forthe Degree of Master of Arts Department of Philosophy Western Michigan University Kalamazoo, Michigan June 1996 IS THE UNIVERSE EXPANDING?: AN HISTORICAL AND PHILOSOPHICAL PERSPECTIVE FOR COSMOLOGISTS STARTING ANEW David A Vlasak, M.A. Western Michigan University, 1996 This study addresses the problem of how scientists ought to go about resolving the current crisis in big bang cosmology. Although this problem can be addressed by scientists themselves at the level of their own practice, this study addresses it at the meta level by using the resources offered by philosophy of science. There are two ways to resolve the current crisis. -
AAS NEWSLETTER Issue 127 a Publication for the Members of the American Astronomical Society
October 2005 AAS NEWSLETTER Issue 127 A Publication for the members of the American Astronomical Society PRESIDENT’S COLUMN know that Henrietta Swan Leavitt measured the Cepheid variable stars in the Magellanic Clouds Robert Kirshner, [email protected] to establish the period-luminosity relation, and that Inside this rung on the distance ladder let Hubble reach As I write this, summer is definitely winding down, M31 and other nearby galaxies. And I recognized George Johnson’s name from his thoughtful pieces 3 and the signs of Fall on a college campus are all in the New York Times science pages. Who Served Us Well: around: urgent overtime work on the last licks of John N. Bahcall summer renovations is underway, vast piles of trash and treasure from cleaning out dorm rooms are But I confess, though I walk on the streets where accumulating, with vigorous competitive double- she lived, work in a building connected by a 5 parking of heavily-laden minivans just ahead. With labyrinth to the one she worked in, and stand on Katrina Affected the Galaxy overhead most of the night, and the the distance ladder every day, my cerebral cortex Physics and summer monsoon in progress in Arizona, the pace is a little short on retrievable biographical details Astronomy (KAPA) of supernova studies slackens just a bit (for me, for Henrietta Swan Leavitt. Johnson has plumbed Community Bulletin anyway) and I had time to do a little summer reading. the Harvard archives, local census records, and the correspondence of Harvard College Board There were too many mosquitoes in Maine to read in a hammock, but there was enough light on the Observatory Directors to give us a portrait of screened porch. -
Booklet 2008-09.Indd
The Shaw Prize The Shaw Prize is an international award to honour individuals who are currently active in their respective fields and who have achieved distinguished and significant advances, who have made outstanding contributions in culture and the arts, or who in other domains have achieved excellence. The award is dedicated to furthering societal progress, enhancing quality of life, and enriching humanity’s spiritual civilization. Preference will be given to individuals whose significant work was recently achieved. Founder's Biographical Note The Shaw Prize was established under the auspices of Mr Run Run Shaw. Mr Shaw, born in China in 1907, is a native of Ningbo County, Zhejiang Province. He joined his brother’s film company in China in the 1920s. In the 1950s he founded the film company Shaw Brothers (Hong Kong) Limited in Hong Kong. He has been Executive Chairman of Television Broadcasts Limited in Hong Kong since the 1970s. Mr Shaw has also founded two charities, The Sir Run Run Shaw Charitable Trust and The Shaw Foundation Hong Kong, both dedicated to the promotion of education, scientific and technological research, medical and welfare services, and culture and the arts. ~ 1 ~ Message from the Chief Executive I am delighted to congratulate the six distinguished scientists who receive this year’s Shaw Prize. Their accomplishments enrich human knowledge and have a profound impact on the advancement of science. This year, the Shaw Prize recognises remarkable achievements in the areas of astronomy, life science and medicine, and mathematical sciences. The exemplary work and dedication of this year’s recipients vividly demonstrate that constant drive for excellence will eventually bear fruit. -
President's Column
AAAS Publication for the members N of the Americanewsletter Astronomical Society September/October 2010, Issue 154 CONTENTS President's Column Debra Meloy Elmegreen, [email protected] 2 Congratulations to all of us in the astronomical community on the completion of the Decadal From the Survey! Two years after the National Research Council organized the Astro2010 Committee to begin its arduous process, the report “New Worlds, New Horizons in Astronomy and Astrophysics” Executive Office is complete. In fact, as I write this article the public roll-out is underway at the Keck Center of the National Academies in Washington, DC. This was truly a community effort, and we should all be proud of it and feel ownership of it. The federal funding agencies and Congress widely view the 3 astronomy decadal process as a model for other disciplines to emulate, and it is extremely important for us to embrace it. Editor, The Astrophysical We are embarking on a period of unprecedented opportunities for astronomical research, thanks to great advances in technology, theory, and observations, and the report presents an exciting Journal Letters and balanced set of science-driven priorities within the framework of realistic budget scenarios. The Astro2010 committee comprised 23 astronomers, selected by the National Academies based on community solicitation of suggested names, who were assisted by panels on different science 4 disciplines, space- and ground-based activities, and study groups on the astronomical infrastructure; these subcommittees had a membership of nearly 200 astronomers from the US astronomical Journals Update community. The Survey report and the panel reports are the culmination of a careful and deliberate consideration of science goals, projects and missions and on the whole astronomical enterprise, based in part on the distillation of over 450 community-submitted white papers, over 100 proposals for 6 research activities, briefings from federal agencies, and 17 Town Halls, along with other federal and international reports. -
Hubble Space Telescope Primer for Cycle 18
January 2010 Hubble Space Telescope Primer for Cycle 18 An Introduction to HST for Phase I Proposers Space Telescope Science Institute 3700 San Martin Drive Baltimore, Maryland 21218 [email protected] Operated by the Association of Universities for Research in Astronomy, Inc., for the National Aeronautics and Space Administration How to Get Started If you are interested in submitting an HST proposal, then proceed as follows: • Visit the Cycle 18 Announcement Web page: http://www.stsci.edu/hst/proposing/docs/cycle18announce Then continue by following the procedure outlined in the Phase I Roadmap available at: http://apst.stsci.edu/apt/external/help/roadmap1.html More technical documentation, such as that provided in the Instrument Handbooks, can be accessed from: http://www.stsci.edu/hst/HST_overview/documents Where to Get Help • Visit STScI’s Web site at: http://www.stsci.edu • Contact the STScI Help Desk. Either send e-mail to [email protected] or call 1-800-544-8125; from outside the United States and Canada, call [1] 410-338-1082. The HST Primer for Cycle 18 was edited by Francesca R. Boffi, with the technical assistance of Susan Rose and the contributions of many others from STScI, in particular Alessandra Aloisi, Daniel Apai, Todd Boroson, Brett Blacker, Stefano Casertano, Ron Downes, Rodger Doxsey, David Golimowski, Al Holm, Helmut Jenkner, Jason Kalirai, Tony Keyes, Anton Koekemoer, Jerry Kriss, Matt Lallo, Karen Levay, John MacKenty, Jennifer Mack, Aparna Maybhate, Ed Nelan, Sami-Matias Niemi, Cheryl Pavlovsky, Karla Peterson, Larry Petro, Charles Proffitt, Neill Reid, Merle Reinhart, Ken Sembach, Paula Sessa, Nancy Silbermann, Linda Smith, Dave Soderblom, Denise Taylor, Nolan Walborn, Alan Welty, Bill Workman and Jim Younger. -
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. -
The History of Star Formation in Galaxies
Astro2010 Science White Paper: The Galactic Neighborhood (GAN) The History of Star Formation in Galaxies Thomas M. Brown ([email protected]) and Marc Postman ([email protected]) Space Telescope Science Institute Daniela Calzetti ([email protected]) Dept. of Astronomy, University of Massachusetts 24 25 26 I 27 28 29 30 0.5 1.0 1.5 V-I Brown et al. The History of Star Formation in Galaxies Abstract If we are to develop a comprehensive and predictive theory of galaxy formation and evolution, it is essential that we obtain an accurate assessment of how and when galaxies assemble their stel- lar populations, and how this assembly varies with environment. There is strong observational support for the hierarchical assembly of galaxies, but by definition the dwarf galaxies we see to- day are not the same as the dwarf galaxies and proto-galaxies that were disrupted during the as- sembly. Our only insight into those disrupted building blocks comes from sifting through the re- solved field populations of the surviving giant galaxies to reconstruct the star formation history, chemical evolution, and kinematics of their various structures. To obtain the detailed distribution of stellar ages and metallicities over the entire life of a galaxy, one needs multi-band photometry reaching solar-luminosity main sequence stars. The Hubble Space Telescope can obtain such data in the outskirts of Local Group galaxies. To perform these essential studies for a fair sample of the Local Universe will require observational capabilities that allow us to extend the study of resolved stellar populations to much larger galaxy samples that span the full range of galaxy morphologies, while also enabling the study of the more crowded regions of relatively nearby galaxies. -
Science & ROGER PENROSE
Science & ROGER PENROSE Live Webinar - hosted by the Center for Consciousness Studies August 3 – 6, 2021 9:00 am – 12:30 pm (MST-Arizona) each day 4 Online Live Sessions DAY 1 Tuesday August 3, 2021 9:00 am to 12:30 pm MST-Arizona Overview / Black Holes SIR ROGER PENROSE (Nobel Laureate) Oxford University, UK Tuesday August 3, 2021 9:00 am – 10:30 am MST-Arizona Roger Penrose was born, August 8, 1931 in Colchester Essex UK. He earned a 1st class mathematics degree at University College London; a PhD at Cambridge UK, and became assistant lecturer, Bedford College London, Research Fellow St John’s College, Cambridge (now Honorary Fellow), a post-doc at King’s College London, NATO Fellow at Princeton, Syracuse, and Cornell Universities, USA. He also served a 1-year appointment at University of Texas, became a Reader then full Professor at Birkbeck College, London, and Rouse Ball Professor of Mathematics, Oxford University (during which he served several 1/2-year periods as Mathematics Professor at Rice University, Houston, Texas). He is now Emeritus Rouse Ball Professor, Fellow, Wadham College, Oxford (now Emeritus Fellow). He has received many awards and honorary degrees, including knighthood, Fellow of the Royal Society and of the US National Academy of Sciences, the De Morgan Medal of London Mathematical Society, the Copley Medal of the Royal Society, the Wolf Prize in mathematics (shared with Stephen Hawking), the Pomeranchuk Prize (Moscow), and one half of the 2020 Nobel Prize in Physics, the other half shared by Reinhard Genzel and Andrea Ghez. -
The Galactic Center: a Laboratory for Fundamental Astrophysics And
The Galactic Center: A Laboratory for Fundamental Astrophysics and Galactic Nuclei An Astro2010 Science White Paper Authors: Andrea Ghez (UCLA; [email protected]), Mark Morris (UCLA), Jessica Lu (Caltech), Nevin Weinberg (UCB), Keith Matthews (Caltech), Tal Alexander (Weizmann Inst.), Phil Armitage (U. of Colorado), Eric Becklin (Ames/UCLA), Warren Brown (CfA), Randy Campbell (Keck) Tuan Do (UCLA), Andrea Eckart (U. of Cologne), Reinhard Genzel (MPE/UCB), Andy Gould (Ohio State), Brad Hansen (UCLA), Luis Ho (Carnegie), Fred Lo (NRAO), Avi Loeb (Harvard), Fulvio Melia (U. of Arizona), David Merritt (RIT), Milos Milosavljevic (U. of Texas), Hagai Perets (Weizmann Inst.), Fred Rasio (Northwestern), Mark Reid (CfA), Samir Salim (NOAO), Rainer Sch¨odel (IAA), Sylvana Yelda (UCLA) Submitted to Science Frontier Panels on (1) The Galactic Neighborhood (GAN) arXiv:0903.0383v1 [astro-ph.GA] 2 Mar 2009 (2) Cosmology and Fundamental Physics (CFP) Supplemental Animations: http://www.astro.ucla.edu/∼ghezgroup/gc/pictures/Future GCorbits.shtml Galactic Center Stellar Dynamics Astro2010 White Paper 1 Abstract As the closest example of a galactic nucleus, the Galactic center presents an exquisite lab- oratory for learning about supermassive black holes (SMBH) and their environs. In this document, we describe how detailed studies of stellar dynamics deep in the potential well of a galaxy offer several exciting directions in the coming decade. First, it will be possible to obtain precision measurements of the Galaxy’s central potential, providing both a unique test of General Relativity (GR) and a detection of the extended dark matter distribution that is predicted to exist around the SMBH. Tests of gravity have not previously been pos- sible on scales larger than our solar system, or in regimes where the gravitational energy of a body is >∼1% of its rest mass energy. -
A Remarkable Panoramic Space Telescope for the 2020'S
A Remarkable Panoramic Space Telescope for the 2020s Dr. Marc Postman (SB ’81, MIT) Space Telescope Science Institute How are stars and galaxies formed? How does the universe work? Astronomers ask big questions. Are we alone? WFIRST: Wide Field Infrared Survey Telescope Dark Energy, Dark Wide-Field Surveys of the Matter, and the Fate of the Universe Universe ? ? Technology Development for The full distribution of planets around stars Exploration of New Worlds National Academy of Sciences Astronomy & Astrophysics Decadal Survey (2010) DARK MATTER DARK ENERGY 26% 69% STARS, GAS, DUST, ALL WE CAN SEE 5% How do we know there is so much dark matter? And what could dark matter be? How do we know there is so much dark energy? And what is it? Do we need new physics? What new experiments do we need to run? What new observations do we need to make? Basic properties of dark matter… • Dark matter is likely a particle, the way protons and neutrons are particles. • These particles must be abundant. • Dark matter barely interacts, if at all, with other matter (except by gravity). • Dark matter does not emit light. • Dark matter is passing through each of us right now (about 3 x 10-7 micrograms every second)*. *Based on E. Siegel, Forbes We already know dark matter cannot be: • Black holes • Neutrinos • Dwarf planets • Cosmic dust • Squirrels https://xkcd.com/2186/ Cluster of galaxies We can measure the mass in a system by measuring orbital speeds and distances 60 50 Mercury 40 Venus 30 Earth Mars 20 Jupiter Orbital Velocity (km/s) Velocity Orbital 10 -
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