12. Singularities and Time-Asymmetry
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The Revival of White Holes As Small Bangs
The Revival of White Holes as Small Bangs Alon Retter1 & Shlomo Heller2 1 86a/6 Hamacabim St., P.O. Box 4264, Shoham, 60850, Israel, [email protected] 2 Zuqim, 86833, Israel, [email protected] Abstract Black holes are extremely dense and compact objects from which light cannot escape. There is an overall consensus that black holes exist and many astronomical objects are identified with black holes. White holes were understood as the exact time reversal of black holes, therefore they should continuously throw away material. It is accepted, however, that a persistent ejection of mass leads to gravitational pressure, the formation of a black hole and thus to the "death of while holes". So far, no astronomical source has been successfully tagged a white hole. The only known white hole is the Big Bang which was instantaneous rather than continuous or long-lasting. We thus suggest that the emergence of a white hole, which we name a 'Small Bang', is spontaneous – all the matter is ejected at a single pulse. Unlike black holes, white holes cannot be continuously observed rather their effect can only be detected around the event itself. Gamma ray bursts are the most energetic explosions in the universe. Long γ-ray bursts were connected with supernova eruptions. There is a new group of γ- ray bursts, which are relatively close to Earth, but surprisingly lack any supernova emission. We propose identifying these bursts with white holes. White holes seem like the best explanation of γ- ray bursts that appear in voids. The random appearance nature of white holes can also explain the asymmetry required to form structures in the early universe. -
Expanding Space, Quasars and St. Augustine's Fireworks
Universe 2015, 1, 307-356; doi:10.3390/universe1030307 OPEN ACCESS universe ISSN 2218-1997 www.mdpi.com/journal/universe Article Expanding Space, Quasars and St. Augustine’s Fireworks Olga I. Chashchina 1;2 and Zurab K. Silagadze 2;3;* 1 École Polytechnique, 91128 Palaiseau, France; E-Mail: [email protected] 2 Department of physics, Novosibirsk State University, Novosibirsk 630 090, Russia 3 Budker Institute of Nuclear Physics SB RAS and Novosibirsk State University, Novosibirsk 630 090, Russia * Author to whom correspondence should be addressed; E-Mail: [email protected]. Academic Editors: Lorenzo Iorio and Elias C. Vagenas Received: 5 May 2015 / Accepted: 14 September 2015 / Published: 1 October 2015 Abstract: An attempt is made to explain time non-dilation allegedly observed in quasar light curves. The explanation is based on the assumption that quasar black holes are, in some sense, foreign for our Friedmann-Robertson-Walker universe and do not participate in the Hubble flow. Although at first sight such a weird explanation requires unreasonably fine-tuned Big Bang initial conditions, we find a natural justification for it using the Milne cosmological model as an inspiration. Keywords: quasar light curves; expanding space; Milne cosmological model; Hubble flow; St. Augustine’s objects PACS classifications: 98.80.-k, 98.54.-h You’d think capricious Hebe, feeding the eagle of Zeus, had raised a thunder-foaming goblet, unable to restrain her mirth, and tipped it on the earth. F.I.Tyutchev. A Spring Storm, 1828. Translated by F.Jude [1]. 1. Introduction “Quasar light curves do not show the effects of time dilation”—this result of the paper [2] seems incredible. -
Hawking Radiation
a brief history of andreas müller student seminar theory group max camenzind lsw heidelberg mpia & lsw january 2004 http://www.lsw.uni-heidelberg.de/users/amueller talktalk organisationorganisation basics ☺ standard knowledge advanced knowledge edge of knowledge and verifiability mindmind mapmap whatwhat isis aa blackblack hole?hole? black escape velocity c hole singularity in space-time notion „black hole“ from relativist john archibald wheeler (1968), but first speculation from geologist and astronomer john michell (1783) ☺ blackblack holesholes inin relativityrelativity solutions of the vacuum field equations of einsteins general relativity (1915) Gµν = 0 some history: schwarzschild 1916 (static, neutral) reissner-nordstrøm 1918 (static, electrically charged) kerr 1963 (rotating, neutral) kerr-newman 1965 (rotating, charged) all are petrov type-d space-times plug-in metric gµν to verify solution ;-) ☺ black hole mass hidden in (point or ring) singularity blackblack holesholes havehave nono hairhair!! schwarzschild {M} reissner-nordstrom {M,Q} kerr {M,a} kerr-newman {M,a,Q} wheeler: no-hair theorem ☺ blackblack holesholes –– schwarzschildschwarzschild vs.vs. kerrkerr ☺ blackblack holesholes –– kerrkerr inin boyerboyer--lindquistlindquist black hole mass M spin parameter a lapse function delta potential generalized radius sigma potential frame-dragging frequency cylindrical radius blackblack holehole topologytopology blackblack holehole –– characteristiccharacteristic radiiradii G = M = c = 1 blackblack holehole -- -
Estimation of Baryon Asymmetry of the Universe from Neutrino Physics
ESTIMATION OF BARYON ASYMMETRY OF THE UNIVERSE FROM NEUTRINO PHYSICS Manorama Bora Department of Physics Gauhati University This thesis is submitted to Gauhati University as requirement for the degree of Doctor of Philosophy Faculty of Science March 2018 I would like to dedicate this thesis to my parents . Abstract The discovery of neutrino masses and mixing in neutrino oscillation experiments in 1998 has greatly increased the interest in a mechanism of baryogenesis through leptogenesis, a model of baryogenesis which is a cosmological consequence. The most popular way to explain why neutrinos are massive but at the same time much lighter than all other fermions, is the see-saw mechanism. Thus, leptogenesis realises a highly non-trivial link between two completely independent experimental observations: the absence of antimatter in the observable universe and the observation of neutrino mixings and masses. Therefore, leptogenesis has a built-in double sided nature.. The discovery of Higgs boson of mass 125GeV having properties consistent with the SM, further supports the leptogenesis mechanism. In this thesis we present a brief sketch on the phenomenological status of Standard Model (SM) and its extension to GUT with or without SUSY. Then we review on neutrino oscillation and its implication with latest experiments. We discuss baryogenesis via leptogenesis through the decay of heavy Majorana neutrinos. We also discuss formulation of thermal leptogenesis. At last we try to explore the possibilities for the discrimination of the six kinds of Quasi- degenerate neutrino(QDN)mass models in the light of baryogenesis via leptogenesis. We have seen that all the six QDN mass models are relevant in the context of flavoured leptogenesis. -
The Large Scale Universe As a Quasi Quantum White Hole
International Astronomy and Astrophysics Research Journal 3(1): 22-42, 2021; Article no.IAARJ.66092 The Large Scale Universe as a Quasi Quantum White Hole U. V. S. Seshavatharam1*, Eugene Terry Tatum2 and S. Lakshminarayana3 1Honorary Faculty, I-SERVE, Survey no-42, Hitech city, Hyderabad-84,Telangana, India. 2760 Campbell Ln. Ste 106 #161, Bowling Green, KY, USA. 3Department of Nuclear Physics, Andhra University, Visakhapatnam-03, AP, India. Authors’ contributions This work was carried out in collaboration among all authors. Author UVSS designed the study, performed the statistical analysis, wrote the protocol, and wrote the first draft of the manuscript. Authors ETT and SL managed the analyses of the study. All authors read and approved the final manuscript. Article Information Editor(s): (1) Dr. David Garrison, University of Houston-Clear Lake, USA. (2) Professor. Hadia Hassan Selim, National Research Institute of Astronomy and Geophysics, Egypt. Reviewers: (1) Abhishek Kumar Singh, Magadh University, India. (2) Mohsen Lutephy, Azad Islamic university (IAU), Iran. (3) Sie Long Kek, Universiti Tun Hussein Onn Malaysia, Malaysia. (4) N.V.Krishna Prasad, GITAM University, India. (5) Maryam Roushan, University of Mazandaran, Iran. Complete Peer review History: http://www.sdiarticle4.com/review-history/66092 Received 17 January 2021 Original Research Article Accepted 23 March 2021 Published 01 April 2021 ABSTRACT We emphasize the point that, standard model of cosmology is basically a model of classical general relativity and it seems inevitable to have a revision with reference to quantum model of cosmology. Utmost important point to be noted is that, ‘Spin’ is a basic property of quantum mechanics and ‘rotation’ is a very common experience. -
Black Hole Termodinamics and Hawking Radiation
Black hole thermodynamics and Hawking radiation (Just an overview by a non-expert on the field!) Renato Fonseca - 26 March 2018 – for the Journal Club Thermodynamics meets GR • Research in the 70’s convincingly brought together two very different areas of physics: thermodynamics and General Relativity • People realized that black holes (BHs) followed some laws similar to the ones observed in thermodynamics • It was then possible to associate a temperature to BHs. But was this just a coincidence? • No. Hawkings (1975) showed using QFT in curved space that BHs from gravitational collapse radiate as a black body with a certain temperature T Black Holes Schwarzschild metric (for BHs with no spin nor electric charge) • All coordinates (t,r,theta,phi) are what you think they are far from the central mass M • Something funny seems to happen for r=2M. But … locally there is nothing special there (only at r=0): r=0: real/intrinsic singularity r=2M: apparent singularity (can be removed with other coordinates) Important caveat: the Schwarzschild solution is NOT what is called maximal. With coordinates change we can get the Kruskal solution, which is. “Maximal”= ability to continue geodesics until infinity or an intrinsic singularity Schwarzschild metric (for BHs with no spin nor electric charge) • r=2M (event horizon) is not special for its LOCAL properties (curvature, etc) but rather for its GLOBAL properties: r<=2M are closed trapped surfaces which cannot communicate with the outside world [dr/dt=0 at r=2M even for light] Fun fact: for null geodesics (=light) we see that +/- = light going out/in One can even integrate this: t=infinite for even light to fall into the BH! This is what an observatory at infinity sees … (Penrose, 1969) Schwarzschild metric (digression) • But the object itself does fall into the BH. -
The Arrow of Time Volume 7 Paul Davies Summer 2014 Beyond Center for Fundamental Concepts in Science, Arizona State University, Journal Homepage P.O
The arrow of time Volume 7 Paul Davies Summer 2014 Beyond Center for Fundamental Concepts in Science, Arizona State University, journal homepage P.O. Box 871504, Tempe, AZ 852871504, USA. www.euresisjournal.org [email protected] Abstract The arrow of time is often conflated with the popular but hopelessly muddled concept of the “flow” or \passage" of time. I argue that the latter is at best an illusion with its roots in neuroscience, at worst a meaningless concept. However, what is beyond dispute is that physical states of the universe evolve in time with an objective and readily-observable directionality. The ultimate origin of this asymmetry in time, which is most famously captured by the second law of thermodynamics and the irreversible rise of entropy, rests with cosmology and the state of the universe at its origin. I trace the various physical processes that contribute to the growth of entropy, and conclude that gravitation holds the key to providing a comprehensive explanation of the elusive arrow. 1. Time's arrow versus the flow of time The subject of time's arrow is bedeviled by ambiguous or poor terminology and the con- flation of concepts. Therefore I shall begin my essay by carefully defining terms. First an uncontentious statement: the states of the physical universe are observed to be distributed asymmetrically with respect to the time dimension (see, for example, Refs. [1, 2, 3, 4]). A simple example is provided by an earthquake: the ground shakes and buildings fall down. We would not expect to see the reverse sequence, in which shaking ground results in the assembly of a building from a heap of rubble. -
Hawking Radiation As Perceived by Different Observers L C Barbado, C Barceló, L J Garay
Hawking radiation as perceived by different observers L C Barbado, C Barceló, L J Garay To cite this version: L C Barbado, C Barceló, L J Garay. Hawking radiation as perceived by different observers. Classical and Quantum Gravity, IOP Publishing, 2011, 10 (12), pp.125021. 10.1088/0264-9381/28/12/125021. hal-00710459 HAL Id: hal-00710459 https://hal.archives-ouvertes.fr/hal-00710459 Submitted on 21 Jun 2012 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Confidential: not for distribution. Submitted to IOP Publishing for peer review 24 March 2011 Hawking radiation as perceived by different observers LCBarbado1,CBarcel´o1 and L J Garay2,3 1 Instituto de Astrof´ısica de Andaluc´ıa(CSIC),GlorietadelaAstronom´ıa, 18008 Granada, Spain 2 Departamento de F´ısica Te´orica II, Universidad Complutense de Madrid, 28040 Madrid, Spain 3 Instituto de Estructura de la Materia (CSIC), Serrano 121, 28006 Madrid, Spain E-mail: [email protected], [email protected], [email protected] Abstract. We use a method recently introduced in Barcel´o et al, 10.1103/Phys- RevD.83.041501, to analyse Hawking radiation in a Schwarzschild black hole as per- ceived by different observers in the system. -
Effect of Quantum Gravity on the Stability of Black Holes
S S symmetry Article Effect of Quantum Gravity on the Stability of Black Holes Riasat Ali 1 , Kazuharu Bamba 2,* and Syed Asif Ali Shah 1 1 Department of Mathematics, GC University Faisalabad Layyah Campus, Layyah 31200, Pakistan; [email protected] (R.A.); [email protected] (S.A.A.S.) 2 Division of Human Support System, Faculty of Symbiotic Systems Science, Fukushima University, Fukushima 960-1296, Japan * Correspondence: [email protected] Received: 10 April 2019; Accepted: 26 April 2019; Published: 5 May 2019 Abstract: We investigate the massive vector field equation with the WKB approximation. The tunneling mechanism of charged bosons from the gauged super-gravity black hole is observed. It is shown that the appropriate radiation consistent with black holes can be obtained in general under the condition that back reaction of the emitted charged particle with self-gravitational interaction is neglected. The computed temperatures are dependant on the geometry of black hole and quantum gravity. We also explore the corrections to the charged bosons by analyzing tunneling probability, the emission radiation by taking quantum gravity into consideration and the conservation of charge and energy. Furthermore, we study the quantum gravity effect on radiation and discuss the instability and stability of black hole. Keywords: higher dimension gauged super-gravity black hole; quantum gravity; quantum tunneling phenomenon; Hawking radiation 1. Introduction General relativity is associated with the thermodynamics and quantum effect which are strongly supportive of each other. A black hole (BH) is a compact object whose gravitational pull is so intense that can not escape the light. -
The Matter – Antimatter Asymmetry of the Universe and Baryogenesis
The matter – antimatter asymmetry of the universe and baryogenesis Andrew Long Lecture for KICP Cosmology Class Feb 16, 2017 Baryogenesis Reviews in General • Kolb & Wolfram’s Baryon Number Genera.on in the Early Universe (1979) • Rio5o's Theories of Baryogenesis [hep-ph/9807454]} (emphasis on GUT-BG and EW-BG) • Rio5o & Trodden's Recent Progress in Baryogenesis [hep-ph/9901362] (touches on EWBG, GUTBG, and ADBG) • Dine & Kusenko The Origin of the Ma?er-An.ma?er Asymmetry [hep-ph/ 0303065] (emphasis on Affleck-Dine BG) • Cline's Baryogenesis [hep-ph/0609145] (emphasis on EW-BG; cartoons!) Leptogenesis Reviews • Buchmuller, Di Bari, & Plumacher’s Leptogenesis for PeDestrians, [hep-ph/ 0401240] • Buchmulcer, Peccei, & Yanagida's Leptogenesis as the Origin of Ma?er, [hep-ph/ 0502169] Electroweak Baryogenesis Reviews • Cohen, Kaplan, & Nelson's Progress in Electroweak Baryogenesis, [hep-ph/ 9302210] • Trodden's Electroweak Baryogenesis, [hep-ph/9803479] • Petropoulos's Baryogenesis at the Electroweak Phase Transi.on, [hep-ph/ 0304275] • Morrissey & Ramsey-Musolf Electroweak Baryogenesis, [hep-ph/1206.2942] • Konstandin's Quantum Transport anD Electroweak Baryogenesis, [hep-ph/ 1302.6713] Constituents of the Universe formaon of large scale structure (galaxy clusters) stars, planets, dust, people late ame accelerated expansion Image stolen from the Planck website What does “ordinary matter” refer to? Let’s break it down to elementary particles & compare number densities … electron equal, universe is neutral proton x10 billion 3⇣(3) 3 3 n =3 T 168 cm− neutron x7 ⌫ ⇥ 4⇡2 ⌫ ' matter neutrinos photon positron =0 2⇣(3) 3 3 n = T 413 cm− γ ⇡2 CMB ' anti-proton =0 3⇣(3) 3 3 anti-neutron =0 n =3 T 168 cm− ⌫¯ ⇥ 4⇡2 ⌫ ' anti-neutrinos antimatter What is antimatter? First predicted by Dirac (1928). -
Light Rays, Singularities, and All That
Light Rays, Singularities, and All That Edward Witten School of Natural Sciences, Institute for Advanced Study Einstein Drive, Princeton, NJ 08540 USA Abstract This article is an introduction to causal properties of General Relativity. Topics include the Raychaudhuri equation, singularity theorems of Penrose and Hawking, the black hole area theorem, topological censorship, and the Gao-Wald theorem. The article is based on lectures at the 2018 summer program Prospects in Theoretical Physics at the Institute for Advanced Study, and also at the 2020 New Zealand Mathematical Research Institute summer school in Nelson, New Zealand. Contents 1 Introduction 3 2 Causal Paths 4 3 Globally Hyperbolic Spacetimes 11 3.1 Definition . 11 3.2 Some Properties of Globally Hyperbolic Spacetimes . 15 3.3 More On Compactness . 18 3.4 Cauchy Horizons . 21 3.5 Causality Conditions . 23 3.6 Maximal Extensions . 24 4 Geodesics and Focal Points 25 4.1 The Riemannian Case . 25 4.2 Lorentz Signature Analog . 28 4.3 Raychaudhuri’s Equation . 31 4.4 Hawking’s Big Bang Singularity Theorem . 35 5 Null Geodesics and Penrose’s Theorem 37 5.1 Promptness . 37 5.2 Promptness And Focal Points . 40 5.3 More On The Boundary Of The Future . 46 1 5.4 The Null Raychaudhuri Equation . 47 5.5 Trapped Surfaces . 52 5.6 Penrose’s Theorem . 54 6 Black Holes 58 6.1 Cosmic Censorship . 58 6.2 The Black Hole Region . 60 6.3 The Horizon And Its Generators . 63 7 Some Additional Topics 66 7.1 Topological Censorship . 67 7.2 The Averaged Null Energy Condition . -
Firewalls and the Quantum Properties of Black Holes
Firewalls and the Quantum Properties of Black Holes A thesis submitted in partial fulfillment of the requirements for the degree of Bachelor of Science degree in Physics from the College of William and Mary by Dylan Louis Veyrat Advisor: Marc Sher Senior Research Coordinator: Gina Hoatson Date: May 10, 2015 1 Abstract With the proposal of black hole complementarity as a solution to the information paradox resulting from the existence of black holes, a new problem has become apparent. Complementarity requires a vio- lation of monogamy of entanglement that can be avoided in one of two ways: a violation of Einstein’s equivalence principle, or a reworking of Quantum Field Theory [1]. The existence of a barrier of high-energy quanta - or “firewall” - at the event horizon is the first of these two resolutions, and this paper aims to discuss it, for Schwarzschild as well as Kerr and Reissner-Nordstr¨omblack holes, and to compare it to alternate proposals. 1 Introduction, Hawking Radiation While black holes continue to present problems for the physical theories of today, quite a few steps have been made in the direction of understanding the physics describing them, and, consequently, in the direction of a consistent theory of quantum gravity. Two of the most central concepts in the effort to understand black holes are the black hole information paradox and the existence of Hawking radiation [2]. Perhaps the most apparent result of black holes (which are a consequence of general relativity) that disagrees with quantum principles is the possibility of information loss. Since the only possible direction in which to pass through the event horizon is in, toward the singularity, it would seem that information 2 entering a black hole could never be retrieved.