Cycles of Time: an Extraordinary New View of the Universe Free
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What Geometries Describe Universe Near Big Bang?
Interdisciplinary Studies of Complex Systems No. 9 (2016) 5{24 c Yuri I. Manin Time Between Real and Imaginary: what Geometries Describe Universe near Big Bang? Yuri I. Manin1 Abstract. For about a century, a great challenge for theoretical physics consisted in understanding the role of quantum mode of description of our Universe (\quantum gravity"). Einstein space{times on the scale of ob- servable Universe do not easily submit to any naive quantization scheme. There are better chances to concoct a satisfying quantum picture of the very early space{time, near the Big Bang, where natural scales of events like inflation extrapolated from current observations resist any purely clas- sical description and rather require quantum input. Many physicists and mathematicians tried to understand the quantum early Universe, sometimes unaware of input of the other community. One of the goals of this article is to contribute to the communication of the two communities. In the main text, I present some ideas and results contained in the recent survey/research papers [Le13] (physicists) and [MaMar14], [MaMar15] (mathematicians). Introduction and survey 0.1. Relativistic models of space{time: Minkowski signature. Most modern mathematical models in cosmology start with description of space{time as a 4{dimensional pseudo{Riemannian manifold M endowed with metric 2 X i k ds = gikdx dx of signature (+; ; ; ) where + refers to time{like tangent vectors, whereas the infinitesimal− light{cone− − consists of null{directions. Each such manifold is a point in the infinite{dimensional configuration space of cosmological models. Basic cosmological models are constrained by Einstein equations 1 Rik Rgik + Λgik = 8πGTik − 2 and/or additional symmetry postulates, of which the most essential for us here are the so called Bianchi IX space{times, here with symmetry group SO(3), cf. -
INVENTING REALITY EALITY “This Book Makes for Smooth Riding Over the Rough Terrain of
“...a rich account of the dogged and often futile attempt of physicists to talk about nature.” —Alan Lightman Author of Time Travel and Papa Joe’s Pipe: Essays on the Human side of Science INVENTING INVENTING REALITY EALITY “This book makes for smooth riding over the rough terrain of ... PHYSICS AS modern physics... [Gregory] steers the reader unerringly to his provocative conclusion: reality is a function of language...” R —Lynn Margulis LANGUAGE Coauthor of Microcosmos, Five Kingdoms, and Origins of Sex Physicists do not discover the physical world. Rather, they invent a physical world—a story that closely fits the facts they create in ex- perimental apparatus. From the time of Aristotle to the present, In- venting Reality explores science’s attempts to understand the world by inventing new vocabularies and new ways to describe nature. Drawing on the work of such modern physicists as Bohr, Einstein, and Feynman, Inventing Reality explores the relationship between language and the world. Using ingenious metaphors, concrete examples from everyday life, and engaging, nontechnical language, Gregory color- fully illustrates how the language of physics works, and demonstrates the notion that, in the words of Einstein, “physical concepts are free creations of the human mind.” BRUCE GREGORY is an Associate Director of the Harvard- Smithsonian Center for Astrophysics. For over twenty years he has made science intelligible to audiences ranging from junior high school students to Members of Congress. B R U C E G R E G O R Y Back cover Front cover INVENTING INVENTING REALITY REALITY PHYSICS AS LANGUAGE ❅ Bruce Gregory For Werner PREFACE Physics has been so immensely successful that it is difficult to avoid the conviction that what physicists have done over the past 300 years is to slowly draw back the veil that stands between us and the world as it really is—that physics, and every science, is the discovery of a ready-made world. -
The State of the Universe a Bold Attempt to Make Sense of Relativity, Quantum Theory and Cosmology
books and arts The state of the Universe A bold attempt to make sense of relativity, quantum theory and cosmology. The Road to Reality: A Complete Guide to the Laws of the Universe by Roger Penrose Jonathan Cape: 2004. 1,094 pp. £30 Jeffrey Forshaw JOSE FUSTA RAGA/CORBIS JOSE FUSTA “The most important and ambitious work of science for a generation.”That’s the claim from the publishers of Roger Penrose’s latest book. The claim is vastly overblown. Certainly Penrose has written a remarkable book: it introduces many of the topics that lie at the cutting edge of research into the fundamental nature of space, time and mat- ter. Although the book aims at a complete survey of modern particle physics and cos- mology, its principal concern is to address the fundamental tension between the two pillars of twentieth-century physics: Einstein’s general theory of relativity and quantum theory. This is a fascinating tension and one that Penrose tries to communicate in a quite uncompromising fashion. Although advertised as popular science, this book will be far from accessible to most non-experts. I suspect that there has never been such a bold attempt to communicate ideas of such mathematical complexity to a general audience. It is Penrose’s hope that Up the junction? Despite progress in many directions, we still haven’t found the one “road to reality”. non-experts will be able to go with the flow and get a taste of the excitement of the field the future, critically assessing the way in of the necessary mathematics. -
Spacetime Warps and the Quantum World: Speculations About the Future∗
Spacetime Warps and the Quantum World: Speculations about the Future∗ Kip S. Thorne I’ve just been through an overwhelming birthday celebration. There are two dangers in such celebrations, my friend Jim Hartle tells me. The first is that your friends will embarrass you by exaggerating your achieve- ments. The second is that they won’t exaggerate. Fortunately, my friends exaggerated. To the extent that there are kernels of truth in their exaggerations, many of those kernels were planted by John Wheeler. John was my mentor in writing, mentoring, and research. He began as my Ph.D. thesis advisor at Princeton University nearly forty years ago and then became a close friend, a collaborator in writing two books, and a lifelong inspiration. My sixtieth birthday celebration reminds me so much of our celebration of Johnnie’s sixtieth, thirty years ago. As I look back on my four decades of life in physics, I’m struck by the enormous changes in our under- standing of the Universe. What further discoveries will the next four decades bring? Today I will speculate on some of the big discoveries in those fields of physics in which I’ve been working. My predictions may look silly in hindsight, 40 years hence. But I’ve never minded looking silly, and predictions can stimulate research. Imagine hordes of youths setting out to prove me wrong! I’ll begin by reminding you about the foundations for the fields in which I have been working. I work, in part, on the theory of general relativity. Relativity was the first twentieth-century revolution in our understanding of the laws that govern the universe, the laws of physics. -
Relativistic Inversion, Invariance and Inter-Action
S S symmetry Article Relativistic Inversion, Invariance and Inter-Action Martin B. van der Mark †,‡ and John G. Williamson *,‡ The Quantum Bicycle Society, 12 Crossburn Terrace, Troon KA1 07HB, Scotland, UK; [email protected] * Correspondence: [email protected] † Formerly of Philips Research, 5656 AE Eindhoven, The Netherlands. ‡ These authors contributed equally to this work. Abstract: A general formula for inversion in a relativistic Clifford–Dirac algebra has been derived. Identifying the base elements of the algebra as those of space and time, the first order differential equations over all quantities proves to encompass the Maxwell equations, leads to a natural extension incorporating rest mass and spin, and allows an integration with relativistic quantum mechanics. Although the algebra is not a division algebra, it parallels reality well: where division is undefined turns out to correspond to physical limits, such as that of the light cone. The divisor corresponds to invariants of dynamical significance, such as the invariant interval, the general invariant quantities in electromagnetism, and the basis set of quantities in the Dirac equation. It is speculated that the apparent 3-dimensionality of nature arises from a beautiful symmetry between the three-vector algebra and each of four sets of three derived spaces in the full 4-dimensional algebra. It is conjectured that elements of inversion may play a role in the interaction of fields and matter. Keywords: invariants; inversion; division; non-division algebra; Dirac algebra; Clifford algebra; geometric algebra; special relativity; photon interaction Citation: van der Mark, M.B.; 1. Introduction Williamson, J.G. Relativistic Inversion, Invariance and Inter-Action. -
Views Expressed Are Those of the 37086
Dædalus coming up in Dædalus: Dædalus on learning Alison Gopnik, Howard Gardner, Jerome Bruner, Susan Carey, Journal of the American Academy of Arts & Sciences Elizabeth Spelke, Patricia Smith Churchland, Clark Glymour, Daniel John Povinelli, and Michael Tomasello Fall 2003 Fall 2003: on science Fall on happiness Martin E. P. Seligman, Richard A. Easterlin, Martha C. Nussbaum, on science Alan Lightman A sense of the mysterious 5 Anna Wierzbicka, Bernard Reginster, Robert H. Frank, Julia E. Annas, Roger Shattuck, Darrin M. McMahon, and Ed Diener Albert Einstein Physics & reality 22 Gerald Holton Einstein’s Third Paradise 26 on progress Joseph Stiglitz, John Gray, Charles Larmore, Randall Kennedy, Peter Pesic Bell & buzzer 35 Sakiko Fukuda-Parr, Jagdish Bhagwati, Richard A. Shweder, and David Pingree The logic of non-Western science 45 others Susan Haack Trials & tribulations 54 Andrew Jewett Science & the promise of democracy on human nature Steven Pinker, Lorraine Daston, Jerome Kagan, Vernon Smith, in America 64 Joyce Appleby, Richard Wrangham, Patrick Bateson, Thomas Sowell, Jonathan Haidt, and Donald Brown poetry Les Murray The Tune on Your Mind & Photographing Aspiration 71 on race Kenneth Prewitt, Orlando Patterson, George Fredrickson, Ian Hacking, Jennifer Hochschild, Glenn Loury, David Hollinger, ½ction Joanna Scott That place 73 Victoria Hattam, and others notes Elizabeth F. Loftus on science under legal assault 84 Perez Zagorin on humanism past & present 87 plus poetry by David Ferry, Richard Wilbur, Franz Wright, Rachel Hadas, W. S. Merwin, Charles Wright, Richard Howard &c.; ½ction by Chuck Wachtel &c.; and notes by Gerald Early, Linda Hutcheon, Jennifer Hochschild, Charles Altieri, Richard Stern, Donald Green, S. -
1 Temporal Arrows in Space-Time Temporality
Temporal Arrows in Space-Time Temporality (…) has nothing to do with mechanics. It has to do with statistical mechanics, thermodynamics (…).C. Rovelli, in Dieks, 2006, 35 Abstract The prevailing current of thought in both physics and philosophy is that relativistic space-time provides no means for the objective measurement of the passage of time. Kurt Gödel, for instance, denied the possibility of an objective lapse of time, both in the Special and the General theory of relativity. From this failure many writers have inferred that a static block universe is the only acceptable conceptual consequence of a four-dimensional world. The aim of this paper is to investigate how arrows of time could be measured objectively in space-time. In order to carry out this investigation it is proposed to consider both local and global arrows of time. In particular the investigation will focus on a) invariant thermodynamic parameters in both the Special and the General theory for local regions of space-time (passage of time); b) the evolution of the universe under appropriate boundary conditions for the whole of space-time (arrow of time), as envisaged in modern quantum cosmology. The upshot of this investigation is that a number of invariant physical indicators in space-time can be found, which would allow observers to measure the lapse of time and to infer both the existence of an objective passage and an arrow of time. Keywords Arrows of time; entropy; four-dimensional world; invariance; space-time; thermodynamics 1 I. Introduction Philosophical debates about the nature of space-time often centre on questions of its ontology, i.e. -
Action at a Distance in Quantum Theory
Mathematics 2015, 3, 329-336; doi:10.3390/math3020329 OPEN ACCESS mathematics ISSN 2227-7390 www.mdpi.com/journal/mathematics Article Action at a Distance in Quantum Theory Jerome Blackman 1,2 1 Syracuse University, Syracuse, NY 13244, USA; E-Mail: [email protected]; Tel.: +315-699-8730 or +754-220-5502. 2 7005 Lakeshore Rd. Cicero, NY 13039, USA Academic Editor: Palle E.T. Jorgensen Received: 8 March 2015 / Accepted: 22 April 2015 / Published: 6 May 2015 Abstract: The purpose of this paper is to present a consistent mathematical framework that shows how the EPR (Einstein. Podolsky, Rosen) phenomenon fits into our view of space time. To resolve the differences between the Hilbert space structure of quantum theory and the manifold structure of classical physics, the manifold is taken as a partial representation of the Hilbert space. It is the partial nature of the representation that allows for action at a distance and the failure of the manifold picture. Keywords: action at a distance; EPR; measurement theory 1. Introduction In many books and articles on quantum theory two different statements appear. The first is that quantum theory is the most accurate theory in the history of physics and the second is that it is an incomplete theory. Both of these statements are true, but the incompleteness assertion usually does not refer to the fact that not all questions are answerable at any given time, which is true of all interesting theories, but that quantum theory is a very uncomfortable fit with our usual picture of what kind of space we live in, namely some sort of three or four dimensional manifold. -
Time in Cosmology
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Philsci-Archive Time in Cosmology Craig Callender∗ C. D. McCoyy 21 August 2017 Readers familiar with the workhorse of cosmology, the hot big bang model, may think that cosmology raises little of interest about time. As cosmological models are just relativistic spacetimes, time is under- stood just as it is in relativity theory, and all cosmology adds is a few bells and whistles such as inflation and the big bang and no more. The aim of this chapter is to show that this opinion is not completely right...and may well be dead wrong. In our survey, we show how the hot big bang model invites deep questions about the nature of time, how inflationary cosmology has led to interesting new perspectives on time, and how cosmological speculation continues to entertain dramatically different models of time altogether. Together these issues indicate that the philosopher interested in the nature of time would do well to know a little about modern cosmology. Different claims about time have long been at the heart of cosmology. Ancient creation myths disagree over whether time is finite or infinite, linear or circular. This speculation led to Kant complaining in his famous antinomies that metaphysical reasoning about the nature of time leads to a “euthanasia of reason”. But neither Kant’s worry nor cosmology becoming a modern science succeeded in ending the speculation. Einstein’s first model of the universe portrays a temporally infinite universe, where space is edgeless and its material contents unchanging. -
Entropy and Gravity
Entropy 2012, 14, 2456-2477; doi:10.3390/e14122456 OPEN ACCESS entropy ISSN 1099-4300 www.mdpi.com/journal/entropy Article Entropy and Gravity Øyvind Grøn Faculty of Technology, Art and Design, Oslo and Akershus University College of Applied Sciences, P. O. Box 4, St. Olavs Plass, N-0130 Oslo, Norway; E-Mail: [email protected]; Tel.:+47-90946460 Received: 26 October 2012; in revised form: 22 November 2012 / Accepted: 23 November 2012 / Published: 4 December 2012 Abstract: The effect of gravity upon changes of the entropy of a gravity-dominated system is discussed. In a universe dominated by vacuum energy, gravity is repulsive, and there is accelerated expansion. Furthermore, inhomogeneities are inflated and the universe approaches a state of thermal equilibrium. The difference between the evolution of the cosmic entropy in a co-moving volume in an inflationary era with repulsive gravity and a matter-dominated era with attractive gravity is discussed. The significance of conversion of gravitational energy to thermal energy in a process with gravitational clumping, in order that the entropy of the universe shall increase, is made clear. Entropy of black holes and cosmic horizons are considered. The contribution to the gravitational entropy according to the Weyl curvature hypothesis is discussed. The entropy history of the Universe is reviewed. Keywords: entropy; gravity; gravitational contraction; cosmological constant; black hole; horizon; Weyl curvature hypothesis; inflationary era PACS Codes: 04.20.-q 1. Introduction The arrow of time arises from the universe being far from equilibrium in a state of low entropy. The Second Law of Thermodynamics requires that the entropy of the universe does not decrease. -
I Speculative Physics: the Ontology of Theory And
Speculative Physics: the Ontology of Theory and Experiment in High Energy Particle Physics and Science Fiction by Clarissa Ai Ling Lee Graduate Program in Literature Duke University Date: _______________________ Approved: ___________________________ N. Katherine Hayles, Co-Supervisor ___________________________ Mark C. Kruse, Co-Supervisor ___________________________ Mark B. Hansen ___________________________ Andrew Janiak ___________________________ Timothy Lenoir Dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate Program in Literature in the Graduate School of Duke University 2014 i v ABSTRACT Speculative Physics: the Ontology of Theory and Experiment in High Energy Particle Physics and Science Fiction by Clarissa Ai Ling Lee Graduate Program in Literature Duke University Date:_______________________ Approved: ___________________________ N. Katherine Hayles, Co-Supervisor ___________________________ Mark C. Kruse, Co-Supervisor ___________________________ Mark B. Hansen ___________________________ Andrew Janiak ___________________________ Timothy Lenoir An abstract of a dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate Program in Literature in the Graduate School of Duke University 2014 i v Copyright by Clarissa Ai Ling Lee 2014 Abstract The dissertation brings together approaches across the fields of physics, critical theory, literary studies, philosophy of physics, sociology of science, and history of science to synthesize a hybrid approach for instigating more rigorous and intense cross- disciplinary interrogations between the sciences and the humanities. I explore the concept of speculation in particle physics and science fiction to examine emergent critical approaches for working in the two areas of literature and physics (the latter through critical science studies), but with the expectation of contributing new insights to media theory, critical code studies, and also the science studies of science fiction. -
The Lifetime Problem of Evaporating Black Holes: Mutiny Or Resignation
The lifetime problem of evaporating black holes: mutiny or resignation Carlos Barcel´o1, Ra´ulCarballo-Rubio1, Luis J. Garay2;3, and Gil Jannes4 1 Instituto de Astrof´ısicade Andaluc´ıa(IAA-CSIC), Glorieta de la Astronom´ıa, 18008 Granada, Spain 2 Departamento de F´ısicaTe´oricaII, Universidad Complutense de Madrid, 28040 Madrid, Spain 3 Instituto de Estructura de la Materia (IEM-CSIC), Serrano 121, 28006 Madrid, Spain 4 Modelling & Numerical Simulation Group, Universidad Carlos III de Madrid, Avda. de la Universidad 30, 28911 Legan´es,Spain E-mail: [email protected], [email protected], [email protected], [email protected] Abstract. It is logically possible that regularly evaporating black holes exist in nature. In fact, the prevalent theoretical view is that these are indeed the real objects behind the curtain in astrophysical scenarios. There are several proposals for regularizing the classical singularity of black holes so that their formation and evaporation do not lead to information-loss problems. One characteristic is shared by most of these proposals: these regularly evaporating black holes present long-lived trapping horizons, with absolutely enormous evaporation lifetimes in whatever measure. Guided by the discomfort with these enormous and thus inaccessible lifetimes, we elaborate here on an alternative regularization of the classical singularity, previously proposed by the authors in an emergent gravity framework, which leads to a completely different scenario. In our scheme the collapse of a stellar object would result in a genuine time-symmetric bounce, which in geometrical terms amounts to the connection of a black-hole geometry with a white-hole geometry in a regular manner.