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In This Issue (Dyed and Woven Cloth) and the Realm of Time and Space (Principles the Natural World)
No. 323 December 2004 Published monthly by Public Relations Center General Administration Div. Nippon Steel Corporation “A Pilgrimage: Colored Fibers Encounter Iron” More about Nippon Steel (A series of works by Kei Tsuji) —Contribution for December 2004— http://www.nsc.co.jp WWW (Works of art focused on “an alliance of iron—closely bound to both earth and man—with the arts of dyeing and weaving”) Born in Tokyo 1953, Kei Tsuji displays her installations, centered on dyeing and weaving, in deserts, woodlands and waterfronts the world over. Produced through a fieldwork approach, her installations represent a continuous pursuit of the connection between herself (dyed and woven cloth) and the realm of time and space (principles of the natural world). In this issue Regular Subscription Feature Story If you have received the web-version The Origin of Iron (Two-part series: 1) of Nippon Steel News, you are already —Birth of the Iron Star: Earth— a registered subscriber, thus no new registration is required. Associates who wish to become subscribers are requested to click on Operating Roundup the icon to complete and submit the registration form. Strategic Alliance between Nippon Steel and BHP Billiton WWW Nippon Steel and BHP Billiton have reached a basic agreement to mutually explore the possibility on strategic alliance for development of new mines and other fields. Operating Roundup Strategic Alliance between Nippon Steel and BHP Billiton WWW Back to Top Back Next No. 323 December 2004 Feature Story The Genesis of Product Making The Origin of Iron (Two-part Series: 1) From the Creation of the Universe to the Evolution of Life IRON formed the earth about 4.6 billion amount to about 232 billion tons, far great- years ago. -
Stellar Dynamics and Stellar Phenomena Near a Massive Black Hole
Stellar Dynamics and Stellar Phenomena Near A Massive Black Hole Tal Alexander Department of Particle Physics and Astrophysics, Weizmann Institute of Science, 234 Herzl St, Rehovot, Israel 76100; email: [email protected] | Author's original version. To appear in Annual Review of Astronomy and Astrophysics. See final published version in ARA&A website: www.annualreviews.org/doi/10.1146/annurev-astro-091916-055306 Annu. Rev. Astron. Astrophys. 2017. Keywords 55:1{41 massive black holes, stellar kinematics, stellar dynamics, Galactic This article's doi: Center 10.1146/((please add article doi)) Copyright c 2017 by Annual Reviews. Abstract All rights reserved Most galactic nuclei harbor a massive black hole (MBH), whose birth and evolution are closely linked to those of its host galaxy. The unique conditions near the MBH: high velocity and density in the steep po- tential of a massive singular relativistic object, lead to unusual modes of stellar birth, evolution, dynamics and death. A complex network of dynamical mechanisms, operating on multiple timescales, deflect stars arXiv:1701.04762v1 [astro-ph.GA] 17 Jan 2017 to orbits that intercept the MBH. Such close encounters lead to ener- getic interactions with observable signatures and consequences for the evolution of the MBH and its stellar environment. Galactic nuclei are astrophysical laboratories that test and challenge our understanding of MBH formation, strong gravity, stellar dynamics, and stellar physics. I review from a theoretical perspective the wide range of stellar phe- nomena that occur near MBHs, focusing on the role of stellar dynamics near an isolated MBH in a relaxed stellar cusp. -
Dark Mater Compact Stars in Pseudo-Complex General Relativity]{Dark Mater Compact Stars in Pseudo-Complex General Relativity
Dark Mater Compact Stars in Pseudo-Complex General Relativity]{Dark Mater Compact Stars in Pseudo-Complex General Relativity César A. Zen Vasconcellos Instituto de Física Universidade Federal do Rio Grande do Sul (UFRGS) Porto Alegre, RS, Brazil E-mail: [email protected] Abstract: In the theory of pseudo-complex General Relativity (pc-GR), the field equations have an extra term, associated to the nature of spacetime, of repulsive character, which is believed to halt the gravitational attractive collapse of matter distributions in the evolution process of compact stars. According to Walter Greiner and Peter Hess, this additional term arises from micro-scale phenomena due to vacuum fluctuations which simulate the presence of dark energy in the Universe. In this contribution we explore the presence of this additional term and propose a toy model consisting of dark matter, represented by Standard Model gauge singlets having their origin in a portal model, held together by the presence of the gravitational interaction and superimposed to this (repulsive) background of dark energy forming a type of unconventional and non-luminous star. The combination of these two ingredients, gravitational attraction and dark energy repulsion, allows in thesis the hydrostatic equilibrium condition of the star to hold. Solving the corresponding field equations and the TOV equations, and assuming that the fluid components interact only gravitationally, we determine the hydrostatic equilibrium equations of the star composed only by dark matter and dark energy, a rare compact object formed solely by exotic content. We them analyze the corresponding results obtained for the equation of state and for the mass-radius relations and we them determine the maximum mass of the exotic star for different parameter configurations.. -
One Or Several Populations of Fast Radio Burst Sources?
One or several populations of fast radio burst sources? M. Caleb1, L. G. Spitler2 & B. W. Stappers1 1Jodrell Bank Centre for Astrophysics, the University of Manchester, Manchester, UK. 2Max-Planck-Institut fu¨r Radioastronomie, Bonn, Germany. arXiv:1811.00360v1 [astro-ph.HE] 1 Nov 2018 1 To date, one repeating and many apparently non-repeating fast radio bursts have been de- tected. This dichotomy has driven discussions about whether fast radio bursts stem from a single population of sources or two or more different populations. Here we present the arguments for and against. The field of fast radio bursts (FRBs) has increasingly gained momentum over the last decade. Overall, the FRBs discovered to date show a remarkable diversity of observed properties (see ref 1, http://frbcat.org and Fig. 1). Intrinsic properties that tell us something about the source itself, such as polarization and burst profile shape, as well as extrinsic properties that tell us something about the source’s environment, such as the magnitude of Faraday rotation and multi-path propagation effects, do not yet present a coherent picture. Perhaps the most striking difference is between FRB 121102, the sole repeating FRB2, and the more than 60 FRBs that have so far not been seen to repeat. The observed dichotomy suggests that we should consider the existence of multiple source populations, but it does not yet require it. Most FRBs to date have been discovered with single-pixel telescopes with relatively large angular resolutions. As a result, the non-repeating FRBs have typically been localized to no bet- ter than a few to tens of arcminutes on the sky (Fig. -
121012-AAS-221 Program-14-ALL, Page 253 @ Preflight
221ST MEETING OF THE AMERICAN ASTRONOMICAL SOCIETY 6-10 January 2013 LONG BEACH, CALIFORNIA Scientific sessions will be held at the: Long Beach Convention Center 300 E. Ocean Blvd. COUNCIL.......................... 2 Long Beach, CA 90802 AAS Paper Sorters EXHIBITORS..................... 4 Aubra Anthony ATTENDEE Alan Boss SERVICES.......................... 9 Blaise Canzian Joanna Corby SCHEDULE.....................12 Rupert Croft Shantanu Desai SATURDAY.....................28 Rick Fienberg Bernhard Fleck SUNDAY..........................30 Erika Grundstrom Nimish P. Hathi MONDAY........................37 Ann Hornschemeier Suzanne H. Jacoby TUESDAY........................98 Bethany Johns Sebastien Lepine WEDNESDAY.............. 158 Katharina Lodders Kevin Marvel THURSDAY.................. 213 Karen Masters Bryan Miller AUTHOR INDEX ........ 245 Nancy Morrison Judit Ries Michael Rutkowski Allyn Smith Joe Tenn Session Numbering Key 100’s Monday 200’s Tuesday 300’s Wednesday 400’s Thursday Sessions are numbered in the Program Book by day and time. Changes after 27 November 2012 are included only in the online program materials. 1 AAS Officers & Councilors Officers Councilors President (2012-2014) (2009-2012) David J. Helfand Quest Univ. Canada Edward F. Guinan Villanova Univ. [email protected] [email protected] PAST President (2012-2013) Patricia Knezek NOAO/WIYN Observatory Debra Elmegreen Vassar College [email protected] [email protected] Robert Mathieu Univ. of Wisconsin Vice President (2009-2015) [email protected] Paula Szkody University of Washington [email protected] (2011-2014) Bruce Balick Univ. of Washington Vice-President (2010-2013) [email protected] Nicholas B. Suntzeff Texas A&M Univ. suntzeff@aas.org Eileen D. Friel Boston Univ. [email protected] Vice President (2011-2014) Edward B. Churchwell Univ. of Wisconsin Angela Speck Univ. of Missouri [email protected] [email protected] Treasurer (2011-2014) (2012-2015) Hervey (Peter) Stockman STScI Nancy S. -
Science Fiction Stories with Good Astronomy & Physics
Science Fiction Stories with Good Astronomy & Physics: A Topical Index Compiled by Andrew Fraknoi (U. of San Francisco, Fromm Institute) Version 7 (2019) © copyright 2019 by Andrew Fraknoi. All rights reserved. Permission to use for any non-profit educational purpose, such as distribution in a classroom, is hereby granted. For any other use, please contact the author. (e-mail: fraknoi {at} fhda {dot} edu) This is a selective list of some short stories and novels that use reasonably accurate science and can be used for teaching or reinforcing astronomy or physics concepts. The titles of short stories are given in quotation marks; only short stories that have been published in book form or are available free on the Web are included. While one book source is given for each short story, note that some of the stories can be found in other collections as well. (See the Internet Speculative Fiction Database, cited at the end, for an easy way to find all the places a particular story has been published.) The author welcomes suggestions for additions to this list, especially if your favorite story with good science is left out. Gregory Benford Octavia Butler Geoff Landis J. Craig Wheeler TOPICS COVERED: Anti-matter Light & Radiation Solar System Archaeoastronomy Mars Space Flight Asteroids Mercury Space Travel Astronomers Meteorites Star Clusters Black Holes Moon Stars Comets Neptune Sun Cosmology Neutrinos Supernovae Dark Matter Neutron Stars Telescopes Exoplanets Physics, Particle Thermodynamics Galaxies Pluto Time Galaxy, The Quantum Mechanics Uranus Gravitational Lenses Quasars Venus Impacts Relativity, Special Interstellar Matter Saturn (and its Moons) Story Collections Jupiter (and its Moons) Science (in general) Life Elsewhere SETI Useful Websites 1 Anti-matter Davies, Paul Fireball. -
Planck Stars: New Sources in Radio and Gamma Astronomy? Nature Astronomy 1 (2017) 0065
Planck stars: new sources in radio and gamma astronomy? Nature Astronomy 1 (2017) 0065 Carlo Rovelli CPT, Aix-Marseille Universit´e,Universit´ede Toulon, CNRS, F-13288 Marseille, France. A new phenomenon, recently studied in theoretical ble according to classical general relativity, but there is physics, may have considerable interest for astronomers: theoretical consensus that they decay via quantum pro- the explosive decay of old primordial black holes via cesses. Until recently, the only decay channel studied was quantum tunnelling. Models predict radio and gamma Hawking evaporation [6], a perturbative phenomenon too bursts with a characteristic frequency-distance relation slow to have astrophysical interest: evaporation time of making them identifiable. Their detection would be of a stellar black hole is 1050 Hubble times. major theoretical importance. What can bring black hole decay within potential ob- The expected signal may include two components [1]: servable reach is a different, non-perturbative, quantum (i) strong impulsive emission in the high-energy gamma phenomenon: tunnelling, the same phenomenon that spectrum (∼ T eV ), and (ii) strong impulsive signals triggers nuclear decay in atoms. The explosion of a black in the radio, tantalisingly similar to the recently dis- hole out of its horizon is forbidden by the classical Ein- covered and \very perplexing" [2] Fast Radio Bursts. stein equations but classical equations are violated by Both the gamma and the radio components are expected quantum tunnelling. Violation in a finite spacetime re- to display a characteristic flattening of the cosmological gion turns out to be sufficient for a black hole to tun- wavelength-distance relation, which can make them iden- nel into a white hole and explode [7]. -
Arxiv:Hep-Ph/0604027V1 4 Apr 2006
SLAC-PUB-11795, hep-ph/0604027 A Universe Without Weak Interactions Roni Harnik1, Graham D. Kribs2, and Gilad Perez3 1Stanford Linear Accelerator Center, Stanford University, Stanford, CA 94309 and Physics Department, Stanford University, Stanford, CA 94305 2Department of Physics and Institute of Theoretical Science University of Oregon, Eugene, OR 97403 3Theoretical Physics Group, Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 [email protected], [email protected], [email protected] Abstract A universe without weak interactions is constructed that undergoes big-bang nucleosynthesis, matter domination, structure formation, and star formation. The stars in this universe are able arXiv:hep-ph/0604027v1 4 Apr 2006 to burn for billions of years, synthesize elements up to iron, and undergo supernova explosions, dispersing heavy elements into the interstellar medium. These definitive claims are supported by a detailed analysis where this hypothetical “Weakless Universe” is matched to our Universe by simultaneously adjusting Standard Model and cosmological parameters. For instance, chemistry and nuclear physics are essentially unchanged. The apparent habitability of the Weakless Universe suggests that the anthropic principle does not determine the scale of electroweak breaking, or even require that it be smaller than the Planck scale, so long as technically natural parameters may be suitably adjusted. Whether the multi-parameter adjustment is realized or probable is dependent on the ultraviolet completion, such as the string landscape. Considering a similar analysis for the cosmological constant, however, we argue that no adjustments of other parameters are able to allow the cosmological constant to raise up even remotely close to the Planck scale while obtaining macroscopic structure. -
The History of Enrichment of the Intergalactic Medium Using Cosmological Simulations
The History of Enrichment of the Intergalactic Medium Using Cosmological Simulations Item Type text; Electronic Dissertation Authors Oppenheimer, Benjamin Darwin Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 03/10/2021 02:22:25 Link to Item http://hdl.handle.net/10150/194237 THE HISTORY OF ENRICHMENT OF THE INTERGALACTIC MEDIUM USING COSMOLOGICAL SIMULATIONS by Benjamin Darwin Oppenheimer A Dissertation Submitted to the Faculty of the DEPARTMENT OF ASTRONOMY In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 2 0 0 8 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Dissertation Committee, we certify that we have read the dissertation prepared by Benjamin Darwin Oppenheimer entitled “The History of Enrichment of the Intergalactic Medium Using Cosmological Simulations” and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy. Date: August 6, 2008 Romeel Dave´ Date: August 6, 2008 Chris Impey Date: August 6, 2008 Jill Bechtold Date: August 6, 2008 Buell Jannuzi Date: August 6, 2008 John Bieging Final approval and acceptance of this dissertation is contingent upon the candi- date's submission of the final copies of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. -
Newsletter Submillimeter Array Newsletter Number 20 | July 2015
SMA Newsletter Submillimeter Array Newsletter Number 20 | July 2015 CONTENTS FROM THE DIRECTOR 1 From the Director SCIENCE HIGHLIGHTS: Dear SMA Newsletter readers, 2 Nuclear Ashes and Outflow in the Eruptive Star Nova I am pleased to congratulate Thomas Kaminski (ESO Chile and MPI Bonn), Hua-Bai Vul 1670 Li (The Chinese University of Hong Kong), Jean Turner (UCLA) and their colleagues 5 Magnetic Fields Shape for their recent publications in Nature, summarized in this Newsletter. Collectively Molecular Cloud Structures 7 A Cosmic Factory of Stars these publications highlight the relative ease and utility of the SMA to observe bright, and Soot – SMA Reveals a chemically rich, galactic sources, and nearby galaxies; and further demonstrate the SMA’s Super Star Cluster of Highly Efficient Star Formation in relatively unique polarization capability. NGC 5253 I would also like to thank members of the SMA correlator group for their continued efforts TECHNICAL HIGHLIGHTS: to provide additional wideband signal-processing capacity. We now regularly observe with bu A SWARM of ROACHs the first tranche of SWARM, albeit at 3/4 speed, in parallel with the aging ASIC correlator, Has Been Deployed for Submillimeter Array Science in service since 2002. While not yet perfect, the additional 2x1.5 GHz bands, coupled with bp Securing Service - Availability the original 2x2 GHz bands of the ASIC correlator and double sideband receiver operation in Hawaii Using Virtual Infrastructure result in an instantaneous bandwidth of 14 GHz. This provides additional flexibility OTHER NEWS during spectral line observations and improves the continuum sensitivity of the SMA by about 40%. -
Palatini-Born-Infeld Gravity and Bouncing Universe
Windows on Quantum Gravity @Madrid, Spain 2015/10/30 Palatini-Born-Infeld Gravity and Bouncing Universe Taishi Katsuragawa (Nagoya Univ.) In collaboration with Meguru Komada (Nagoya Univ.), Shin’ichi Nojiri (Nagoya Univ. & KMI) Based on arXiv:1409.1663 Alternative Theories to General Relativity GR is simple but successful theory. Combining the SM based on QFT, our Universe is described well. Planck (2013) However, there are many reasons and motivations to consider alternative theories of gravity to GR. 1 Modification inspired by IR and UV Physics Low energy scale The observation implies the existence of Dark energy and Dark matter. 120 • Cosmological constant problem Λ푡ℎ푒표 ∼ 10 Λ표푏푠 • Origin of Cold Dark Matter etc. It may be possible to explain these two “dark” components in terms of modified gravity. High energy scale GR loses the predictability at the Planck scale where both GR and QFT are required simultaneously. • Singularity and evaporation of black holes ← Today’s topic • Initial singularity (Big Bang scenario) We can regard modified gravity as effective field theory of quantum gravity. 2 Table of contents 1. Introduction 2. Born-Infeld Gravity in Palatini Formalism 3. Bouncing Universe 4. Black Hole Formation 5. Summary and Discussion 3 Born-Infeld Gravity in Palatini Formalism 4 Born-Infeld Electrodynamics The Born-Infeld type theory was first proposed as a non-linear model of electromagnetics. In the Born-Infeld model, a new scale is introduced. 1. Gauge invariant 2. Lorentz invariant 3. To restore the Maxwell theory Born and Infeld (1934) where, 휆 is a parameter with dimension 푙푒푛푔푡ℎ 2. Because the action includes the square root, there appear the upper limit in the strength given by the scale, which may have suggested that there might not appear the divergence. -
Gravity-Superconductor Interactions
id2441218 pdfMachine by Broadgun Software - a great PDF writer! - a great PDF creator! - http://www.pdfmachine.com http://www.broadgun.com Mehtapress 2013 Print - ISSN : 2319–9814 Journal of Online - ISSN : 2319–9822 SpFauclle pEapxepr loration Full Paper WWW.MEHTAPRESS.COM P.A.Murad* An assessment concerning neutron stars and Morningstar Applied Physics, LLC, space propulsion implications Vienna, VA 22182, (USA) E-mail: [email protected] PACS: 04.50.Kd, 04.80.Cc, 06.30.Dr, Abstract 06.30. Gv, 97.10.-q, 97.10.Gz, 97.10.Xq, 97.60.Gb, 97.60.Jd, 97.60.Lf, 97.80.-d There are many uncertainties concerning stellar evolution of neutron stars. Neutron stars might possess multipolar architecture in lieu of a single dipole claimed by the conventional wisdom. The multipole issue cannot be resolved using a single observer reference point Received: April 30, 2013 such as the Earth, but would require an additional non-terrestrial observer location with a Accepted: June 24, 2013 significant offset. Without observing multiple beacons, we could not verify or deny the Published: July 29, 2013 existence of multiple poles from observing the sweeping lighthouse effect from Earth. Moreover, a neutron star’s magnetic field may be created by differences between the neutron core and a gas surface layer of protons and electrons. These differences between *Corresponding author’s Name & Add. the layers constitute charges and moving currents that result in a magnetic field supported by a fast moving rotating core. If electrons in Cooper pairs exist in a neutron star, then the amount of magnetism may increase by a similar order via superconductivity.