Dark Matter May Be a Possible Amplifier of Black Hole
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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 -- -
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. -
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. -
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 . -
White Hole-Black Hole Algorithm
The National Conference for Postgraduate Research 2016, Universiti Malaysia Pahang White Hole-Black Hole Algorithm Suad Khairi Mohammed Faculty of Electrical and Electronics Engineering University Malaysia Pahang Pahang, Malaysia [email protected] Zuwairie Ibrahim Faculty of Electrical and Electronics Engineering University Malaysia Pahang Pahang, Malaysia [email protected] Hamdan Daniyal Faculty of Electrical and Electronics Engineering University Malaysia Pahang Pahang, Malaysia [email protected] address Nor Azlina Ab. Aziz Faculty of Engineering and Technology Multimedia University 75450 Melaka, Malaysia [email protected] This paper proposes a new optimization algorithm based on the law of gravity. In the proposed algorithm, the black ــــAbstract hole sucks up the star that crosses the event horizon, and a white hole emits the star from its event horizon. Both black and white holes attract stars. The white hole-black hole algorithm (WH-BH) starts with an initial population of candidate solutions to an optimization problem and an objective function that is calculated for them. The white hole is selected to be the worst candidate (star), and the black hole will be the best star at each iteration of the WH-BH algorithm. The CEC2014 test functions are applied to evaluate the performance of the WH-BH. Keywords—Nature-inspired algorithm, White hole, CEC2014. 1. INTRODUCTION Every technological process has to achieve optimality in terms of time and complexity, and this led the researchers to design and obtain best possible or better solutions. In previous studies, several mathematical solutions were provided by various researchers to solve optimization problems. The complexity of the proposed mathematical solutions is very high, which requires an enormous amount of computational work. -
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]. -
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. -
Black Holes and Black Hole Thermodynamics Without Event Horizons
General Relativity and Gravitation (2011) DOI 10.1007/s10714-008-0739-9 RESEARCHARTICLE Alex B. Nielsen Black holes and black hole thermodynamics without event horizons Received: 18 June 2008 / Accepted: 22 November 2008 c Springer Science+Business Media, LLC 2009 Abstract We investigate whether black holes can be defined without using event horizons. In particular we focus on the thermodynamic properties of event hori- zons and the alternative, locally defined horizons. We discuss the assumptions and limitations of the proofs of the zeroth, first and second laws of black hole mechan- ics for both event horizons and trapping horizons. This leads to the possibility that black holes may be more usefully defined in terms of trapping horizons. We also review how Hawking radiation may be seen to arise from trapping horizons and discuss which horizon area should be associated with the gravitational entropy. Keywords Black holes, Black hole thermodynamics, Hawking radiation, Trapping horizons Contents 1 Introduction . 2 2 Event horizons . 4 3 Local horizons . 8 4 Thermodynamics of black holes . 14 5 Area increase law . 17 6 Gravitational entropy . 19 7 The zeroth law . 22 8 The first law . 25 9 Hawking radiation for trapping horizons . 34 10 Fluid flow analogies . 36 11 Uniqueness . 37 12 Conclusion . 39 A. B. Nielsen Center for Theoretical Physics and School of Physics College of Natural Sciences, Seoul National University Seoul 151-742, Korea [email protected] 2 A. B. Nielsen 1 Introduction Black holes play a central role in physics. In astrophysics, they represent the end point of stellar collapse for sufficiently large stars. -
The Discrepancy in Redshift Between Associated Galaxies and Quasars
The Discrepancy in Redshift Between Associated Galaxies and Quasars Michael J Savins March 28, 2011 Rev. 3 April 25, 2011 E-mail [email protected] Abstract There is considerable evidence to suggest that many apparent quasar galaxy pairs, actually are pairs despite their difference in red shift. Therefore, the light leaving the quasar must be gravitationally red shifted at source. However, one might expect the quasar to be blue shifted relative to the galaxy in view of the truly gigantic amount of energy being released ejecting huge volumes of material at relativistic speed. The problem then is how to account for the difference, what mechanism is capable of turning a blue shift into a considerable red shift other than cosmological expansion ? The answer is time or more precisely the rate of flow of time. A quasar alters the rate of flow of time in its locality by the following Rt =E/m + -ma. The quasar by attempting to reverse time in its vicinity slows down the universal rate of flow of time in its locality. This slow down of the rate of flow of time or time dilation results in light leaving the quasar being far red shifted at source. This rules out a black hole as being a candidate for the quasar as black holes and galaxies share the same time frame, this means it has to be a white hole which is time reversed in comparison to the rest of the universe Key words Gravity, time, black hole, white hole, redshift, cosmological expansion, Hubbles Law, cyclic universe, matter, antimatter, accretion disc, ionized gas, filaments, spiral galaxy, quasar ejection, relativistic speed. -
Table of Contents (Print)
PHYSICAL REVIEW D PERIODICALS For editorial and subscription correspondence, Postmaster send address changes to: please see inside front cover (ISSN: 1550-7998) APS Subscription Services P.O. Box 41 Annapolis Junction, MD 20701 THIRD SERIES, VOLUME 94, NUMBER 8 CONTENTS D15 OCTOBER 2016 The Table of Contents is a total listing of Parts A and B. Part A consists of articles 081101–084026, and Part B articles 084027–089902(E) PART A RAPID COMMUNICATIONS Coherent observations of gravitational radiation with LISA and gLISA (5 pages) ................................................ 081101(R) Massimo Tinto and José C. N. de Araujo Viscosity of fused silica and thermal noise from the standard linear solid model (5 pages) ..................................... 081102(R) N. M. Kondratiev and M. L. Gorodetsky Anomalous magnetohydrodynamics in the extreme relativistic domain (6 pages) ................................................. 081301(R) Massimo Giovannini Quantum simulation of traversable wormhole spacetimes in a dc-SQUID array (6 pages) ....................................... 081501(R) Carlos Sabín Black hole field theory with a firewall in two spacetime dimensions (6 pages) ................................................... 081502(R) C. T. Marco Ho (何宗泰), Daiqin Su (粟待欽), Robert B. Mann, and Timothy C. Ralph ARTICLES Modulation sensitive search for nonvirialized dark-matter axions (13 pages) ...................................................... 082001 J. Hoskins, N. Crisosto, J. Gleason, P. Sikivie, I. Stern, N. S. Sullivan, D. B. Tanner, C. Boutan, M. Hotz, R. Khatiwada, D. Lyapustin, A. Malagon, R. Ottens, L. J. Rosenberg, G. Rybka, J. Sloan, A. Wagner, D. Will, G. Carosi, D. Carter, L. D. Duffy, R. Bradley, J. Clarke, S. O’Kelley, K. van Bibber, and E. J. Daw Search for ultrarelativistic magnetic monopoles with the Pierre Auger observatory (12 pages) ................................