Time Reborn: from the Crisis in Physics to the Future of the Universe Pdf

Total Page:16

File Type:pdf, Size:1020Kb

Time Reborn: from the Crisis in Physics to the Future of the Universe Pdf FREE TIME REBORN: FROM THE CRISIS IN PHYSICS TO THE FUTURE OF THE UNIVERSE PDF Lee Smolin | 352 pages | 15 Jul 2014 | Penguin Books Ltd | 9780141046525 | English | London, United Kingdom Time Reborn: From the Crisis in Physics to the Future of the Universe - Lee Smolin - Google книги Smolin argues for what he calls a revolutionary view that time is real, in contrast to existing scientific orthodoxy which holds that time is merely a "stubbornly persistent illusion" Einstein 's words. Time Reborn is divided into two parts: Part I describes established physics and its history from the time of Plato and the main established ideas, Newtonian physics and Leibniz ' philosophical views that countered Newton's e. Part II describes Smolin's views his "future" for physics, relying on his and ideas of others on why these all are slightly wrong, that is, the need to reestablish time as fundamental and Time Reborn: From the Crisis in Physics to the Future of the Universe space as non-fundamental, rather than vice versa, that was Einstein's view through e. Smolin asserts that overturning the existing orthodoxy is the best hope for finding solutions to contemporary physics problems, such as bringing gravity into line with the rest of the currently accepted models, [1] the nature of the quantum world and its unification with spacetime and cosmology. The book's topic was the subject of the author's presentation at the Royal Society of Arts. Through his brilliant writing [in The Trouble with Physics ] and articulate arguments, readers. Now, in Time RebornSmolin attempts to chip away at basic theories of Time Reborn: From the Crisis in Physics to the Future of the Universe physics. He makes the case that by doing away with time, existing theories are missing a trick [ Evolution in time is secondary, a by-product of the theory. This bothers Smolin. A timeless view of reality is, he says repeatedly, incomplete where do the initial conditions or laws come from? He believes that a better description of time lies at the heart of some of the big questions, such as the marriage of quantum physics and general relativity. Smolin sketches an alternative path for modern physics. Inspired by the ideas of Brazilian philosopher and political theorist, Roberto Mangabeira Ungerwho argues that social structures emerge without an underlying natural order or guiding principle, Smolin develops some of the ideas. Kirkus Reviews described the book, which omits mathematical explanations, as being as much philosophy as science, and as providing "a flood of ideas from an imaginative thinker. From Wikipedia, the free encyclopedia. Time Reborn Hardcover edition. The Guardian. Archived from the original on July 28, Royal Society of Arts. May 21, Einstein online. Retrieved June 8, Newton's view of the universe is manifestly background dependent [. In modern parlance, theirs is a relationist point of view. For a relationist, there is no background of absolute space and time. Institute for Ethics and Emerging Technologies. Archived from the original on August 9, Macmillan Publishers Limited. April 25, Bibcode : Natur. Retrieved August 19, — via Time Reborn website. The New York Times. Kirkus Reviews. Philosophy of time. B- theory of time Compatibilism and incompatibilism Determinism Endurantism Eternalism Four-dimensionalism Fatalism Temporal finitism Indeterminism Perdurantism Presentism Static interpretation of time. Categories : non-fiction books Books by Lee Smolin Contemporary philosophical literature English-language books Philosophy of time Popular physics books. Namespaces Article Talk. Views Read Edit View history. Help Learn to edit Community portal Recent changes Upload file. Download as PDF Printable version. Hardcover edition. Houghton Mifflin Harcourt. The Trouble with Physics The Singular Universe and the Reality of Time Time Reborn - Wikipedia Michael Berry is unpersuaded by a radical theory that tries to reinstate the concept of absolute time. In fundamental physics, progress has come from unification: connecting concepts that were previously considered separate. Lee Smolin is a counter-revolutionary. In a wide-ranging argument, he aims to reinstate absolute time as a fundamental and real aspect of nature. He emphasises deep discordances in current thinking. But current physical theory is timeless — the laws of Newtonian and quantum physics are the same every when as well as everywhere — and they look the same backwards as forwards. History enters almost casually, after specifying the initial conditions on which the laws act to generate the subsequent evolution of the system being studied. While fully recognising the fruits of this divide-and-rule approach to physics, he thinks it must fail when applied to the universe as a whole. One reason is that in our most fundamental theory, namely quantum mechanics, the state of a system describes possible observations probabilistically, presupposing many identical copies individual atoms, for example in order to compare the predictions of theory with the statistics of observations. But this procedure cannot be applied to the entire universe: by definition, there is only one. Time Reborn: From the Crisis in Physics to the Future of the Universe see the force of this argument but interpret it differently: as a good reason not to try to apply quantum physics to the whole universe. This looks like boxes again: choosing what to study and ignoring the rest — with the difference that what is ignored is now inside. A sufficiently powerful computer, programmed with the present state of all the constituents, could predict the entire future of the universe and retrodict its pastimplying a completely determined world. Nor do I, but we need not fear it because the underlying argument is fallacious. In this sense that is, for unstable systems, unlike the Moon, for exampleNewtonian dynamics is not predictive. He is no relativity denier. As he explains, relativity can be re-expressed so as to be compatible with an absolute Time Reborn: From the Crisis in Physics to the Future of the Universe. But since this is observationally equivalent to the usual formulation, there seems no reason to claim fundamental status for the absolute-time version. The case he makes is both deep and troubling, and he presents it with clarity and grace. It deserves to be taken seriously. But I remain unpersuaded by his arguments for reintrodu-cing absolute time. Get a month's unlimited access to THE content online. Just register and complete your career summary. Registration is free and only takes a moment. Once registered you can read a total of 3 articles each month, plus:. Already registered or a current subscriber? Sign in now. Skip to main content. June 27, Share on twitter Share on facebook Share on linkedin Share on whatsapp Share on mail. Please login or register to read this article. Register to continue Get a month's unlimited access to THE content online. Once registered you can read a total of 3 articles each month, plus: Sign up for the editor's highlights Receive World University Rankings news first Get job alerts, shortlist jobs and save job searches Participate Time Reborn: From the Crisis in Physics to the Future of the Universe reader discussions and post comments Register. Have your say Log in or register to post comments. You might also like Nobelist: keep faith, because Covid vaccine is just round corner. By Jack Grove. History made as two female scientists take Nobel Prize in Chemistry. Black hole researchers win Nobel Prize in Physics. See all jobs. Time Reborn: From the Crisis in Physics to the Future of the Universe by Lee Smolin Te puede interesar:. It shows how fragile our current physical understanding of nature is when confronted with deep philosophical issues. If only for that, the book is worth reading. But its author should be credited for a variety of reasons. First of all, for his emphasis on the reality of time. The book rightly points out the main drawbacks of the current most outstanding physical theories when dealing with time. For the reader interested in a quick summary, comparisons in pp. However, Smolin's criticism of the Newtonian paradigm runs throughout the book because of the latter's sharp distinction between initial conditions and timeless dynamical law. Relativity turns out to be affected by this shortcoming even more acutely. Since any talk of motion in time could be translated into mathematical theorems about a timeless geometry, what is real is all the events of the universe taken together. The reality of the world consists in its history taken as one cf. Even more sophisticated proposals for a quantum gravity theory, like loop quantum theory, fit into the Newtonian paradigm cf. These critiques are not unmotivated. The author is well aware of the scientific method's limits when it is applied to the whole of the universe cf. This is the fallacy of extending the "physics-in-a-box" method to a no-box situation. Physics always make an implicit division of reality into a subsystem, whose dynamic is to be studied, and an environment, whose physical influence is encapsulated in simplified boundary conditions. However, it is extremely doubtful that such a priori divisions can work for the whole universe's dynamics. Quite remarkably, Smolin closely adheres to epistemic criteria for picking out promising theories that extend beyond the Big Bang. His own theory of cosmological natural selection —for which black holes are fathers of new universes and black-hole abundance in a universe correlates well with its specific biofriendliness—does better than any multiverse theory. The latter merely provides a selection principle, while the former accounts for our world as a typical universe cf. Moreover, multiverse theories fall into the statistical fallacy of taking advantage of the freedom to arbitrarily choose a probability distribution that describes unobservable entities and thus cannot be checked independently cf.
Recommended publications
  • Why Do We Remember? the Communicative Function of Episodic Memory
    BEHAVIORAL AND BRAIN SCIENCES (2018), Page 1 of 63 doi:10.1017/S0140525X17000012,e1 Why do we remember? The communicative function of episodic memory Johannes B. Mahr Department of Cognitive Science, Cognitive Development Center, Central European University, 1051 Budapest, Hungary [email protected] https://cognitivescience.ceu.edu/people/johannes-mahr Gergely Csibra Department of Cognitive Science, Cognitive Development Center, Central European University, 1051 Budapest, Hungary [email protected] https://cognitivescience.ceu.edu/people/gergely-csibra Abstract: Episodic memory has been analyzed in a number of different ways in both philosophy and psychology, and most controversy has centered on its self-referential, autonoetic character. Here, we offer a comprehensive characterization of episodic memory in representational terms and propose a novel functional account on this basis. We argue that episodic memory should be understood as a distinctive epistemic attitude taken toward an event simulation. In this view, episodic memory has a metarepresentational format and should not be equated with beliefs about the past. Instead, empirical findings suggest that the contents of human episodic memory are often constructed in the service of the explicit justification of such beliefs. Existing accounts of episodic memory function that have focused on explaining its constructive character through its role in future-oriented mental time travel do justice neither to its capacity to ground veridical beliefs about the past nor to its representational format. We provide an account of the metarepresentational structure of episodic memory in terms of its role in communicative interaction. The generative nature of recollection allows us to represent and communicate the reasons why we hold certain beliefs about the past.
    [Show full text]
  • The Matter of Time
    Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 15 June 2021 doi:10.20944/preprints202106.0417.v1 Article The matter of time Arto Annila 1,* 1 Department of Physics, University of Helsinki; [email protected] * Correspondence: [email protected]; Tel.: (+358 44 204 7324) Abstract: About a century ago, in the spirit of ancient atomism, the quantum of light was renamed the photon to suggest its primacy as the fundamental element of everything. Since the photon carries energy in its period of time, a flux of photons inexorably embodies a flow of time. Time comprises periods as a trek comprises legs. The flows of quanta naturally select optimal paths, i.e., geodesics, to level out energy differences in the least time. While the flow equation can be written, it cannot be solved because the flows affect their driving forces, affecting the flows, and so on. As the forces, i.e., causes, and changes in motions, i.e., consequences, cannot be separated, the future remains unpre- dictable, however not all arbitrary but bounded by free energy. Eventually, when the system has attained a stationary state, where forces tally, there are no causes and no consequences. Then time does not advance as the quanta only orbit on and on. Keywords: arrow of time; causality; change; force; free energy; natural selection; nondeterminism; quantum; period; photon 1. Introduction We experience time passing, but the experience itself lacks a theoretical formulation. Thus, time is a big problem for physicists [1-3]. Although every process involves a passage of time, the laws of physics for particles, as we know them today, do not make a difference whether time flows from the past to the future or from the future to the past.
    [Show full text]
  • The Singular Universe and the Reality of Time: a Proposal in Natural Philosophy
    philosophies Book Review The Singular Universe and the Reality of Time: A Proposal in Natural Philosophy. By Roberto Mangabeira Unger and Lee Smolin. Cambridge University Press: Cambridge, UK, 2014; 566 pp.; ISBN-10: 1107074061, ISBN-13: 978-1107074064 Matt McManus ID Politics Science and International Relations, Tecnológico de Monterrey, Toronto, ON M6B 1T2, Canada; [email protected] Received: 14 July 2018; Accepted: 17 July 2018; Published: 18 July 2018 To do genuinely interdisciplinary and transdisciplinary work is the goal of many scholars. Some achieve it better than others. But to engage in truly systematic and all-encompassing scholarship almost seems anachronistic, not to mention a trifle arrogant. Given the complexities involved in mastering even a single discipline, who could have the audacity to claim expertise across them all. Such ambition and systematicity, not to mention the borderline audacity that underlies it, is part of the thrill that comes from reading any book Roberto Unger. Where others might painstakingly tie themselves into knots justifying their right to engage in interdisciplinary and transdisciplinary work, Unger simply steamrolls over all objections to think and write about whatever he wishes. In many, this might simply be intellectual over reach. But Unger is the rare exception. His seemingly encyclopediac capacity for philosophical systematization has moved from impressive to genuinely inspiring in his recent work. Unger began his career at Harvard Law in the 1970s, as a founding member of the critical legal theory movement in American jurisprudence. His youthful manuscript, Knowledge and Politics, remains a minor classic and develops a reasonably novel criticism of liberal legalism.
    [Show full text]
  • Conjectures on Spacetime
    Conjectures on SpaceTime Alessandro Capurso – [email protected] – linkedin.com/in/capurso/ v190915 - Accepted as contribution at TM2019 INAF conference (Turin, Italy) Available online at indico.ict.inaf.it/event/751/contributions/5182/ Abstract Index The aim of this contribution is to propose new Abstract ................................................................................... 1 conjectures on SpaceTime variables and their description Index ........................................................................................ 1 through the concepts of network and coherent decoding (borrowed from Information Theory) and to offer a Variables and Geometry ....................................................... 2 possible wider perspective on SpaceTime fabric and Time, Memory and discreteness ..................................... 2 evolution. The model follows latest efforts to restore the Imaginary time and Information Space......................... 2 importance of Time in Physics (as Smolin in [1]). Perception of each Self ..................................................... 3 The critical step suggested is towards how we perceive AdS/CFT and Neural networks..................................... 4 SpaceTime dimensions: a 4D quantized expanding Living on the Surface ............................................................ 6 SpaceTime with 2 components for Information Space and Few bits of SpaceTime ....................................................... 6 2 orthogonal time-momentum components is considered. The time-dimensions
    [Show full text]
  • Time Really Passes, Science Can't Deny That
    Time Really Passes, Science Can’t Deny That Nicolas Gisin Group of Applied Physics, University of Geneva, 1211 Geneva 4, Switzerland (Dated: February 5, 2016) Today’s science provides quite a lean picture of time as a mere geometric evolution parameter. I argue that time is much richer. In particular, I argue that besides the geometric time, there is creative time, when objective chance events happen. The existence of the latter follows straight from the existence of free-will. Following the french philosopher Lequyer, I argue that free-will is a prerequisite for the possibility to have rational argumentations, hence can’t be denied. Consequently, science can’t deny the existence of creative time and thus that time really passes. I. INTRODUCTION ism1, according to which, all of today’s facts were neces- sary given the past and the laws of nature. Notice that the past could be yesterday or the big-bang billions of What is free-will for a physicist? This is a very per- years ago. Indeed, according to scientific determinism, sonal question. Most physicists pretend they don’t care, nothing truly new ever happens, everything was set and that it is not important to them, at least not in their pro- 2 determined at the big-bang . This is the view today’s fessional life. But if pressed during some evening free dis- physics offers and I always found it amazing that many cussions, after a few beers, surprising answers come out. people, including clever people, do really believe in this Everything from “obviously I enjoy free-will” to “obvi- [3].
    [Show full text]
  • Entropy, Quantum Mechanics, and Information in Complex Systems a Plea for Ontological Pluralism
    European Journal of Science and Theology, February 2016, Vol.12, No.1, 17-37 _______________________________________________________________________ ENTROPY, QUANTUM MECHANICS, AND INFORMATION IN COMPLEX SYSTEMS A PLEA FOR ONTOLOGICAL PLURALISM Javier Sánchez-Cañizares* University of Navarra, ‘Mind-brain Group’, Institute for Culture and Society (ICS), and CRYF Group, School of Ecclesiastical Philosophy, 31009 Pamplona, Spain (Received 22 April 2015, revised 18 May 2015) Abstract Complex dynamical systems (CDS) are providing a new way of understanding nature. Complexity needs the interplay of different levels in reality and a redefinition of the epistemic approaches in the transition from lower to upper levels. Traditionally, the concept of emergence has tried to bring together the philosophical explanations for the differentiation and crossover between levels. However, it is highly controversial whether emergence is merely epistemic or truly ontic. In this article, I present the philosophical challenges posed by the emergence of CDS regarding conventional epistemic reductionism. I make a strong case for ontic emergence and, therefore, an ontologically plural universe focusing on three conundrums of current Science: the Second Law of Thermodynamics, the measurement problem in Quantum Mechanics, and the symbol grounding problem. I conclude that all of them are interwoven, point towards rejection of naturalistic monism, and suggest the presence of a transcendent logos in nature. Keywords: entropy, Quantum Mechanics, symbol grounding problem,
    [Show full text]
  • The Physics of Augustine: the Matter of Time, Change and an Unchanging God
    Religions 2015, 6, 221–244; doi:10.3390/rel6010221 OPEN ACCESS religions ISSN 2077-1444 www.mdpi.com/journal/religions Article The Physics of Augustine: The Matter of Time, Change and an Unchanging God Thomas Nordlund Department of Physics, University of Alabama at Birmingham, 1300 University Blvd., Birmingham, AL 35294-1170, USA; E-Mail: [email protected]; Tel.: +1-205-934-0340; Fax: +1-205-934-8042 Academic Editors: Scott McGinnis and Chris Metress Received: 4 January 2015 / Accepted: 15 February 2015 / Published: 17 March 2015 Abstract: Scientific questions posed by St. Augustine, early father of the Christian church, are presented as a part of a proposed undergraduate course for religion and philosophy students. Augustine regularly seasons his religious, philosophical and moral investigations with analysis focused on the physical nature of the universe and how it can be quantified: “And yet, O Lord, we do perceive intervals of time, and we compare them with each other, and we say that some are longer and others are shorter” (Confessions, Book 11). The physical analysis is sometimes extended, pressing the attention and grasp of the unsuspecting student of religion or philosophy. Though Augustine emphasizes that true knowledge comes from faith and revelation, his physical inquiries imply that he values such analysis as a way toward truth. In contrast, Master of Divinity programs, which train the majority of Western Christian ministers, require little science experience and usually no physics. Serious investigation of Augustine’s physical explorations reveal an alternative way of understanding scripture, especially Jesus’ sayings: could the master engineer who created the universe sometimes be speaking in straightforward scientific terms? Keywords: Augustine; pedagogy; core texts/great books programs; history of Christianity; physics; time; science and religion 1.
    [Show full text]
  • 2014 TSC Tucson 20Th Anniv. Program Abstracts.Pdf
    20th Anniversary Conference Toward a Science of Consciousness April 21-26, 2014 Tucson, Arizona Tucson Marriott University Park Hotel Sponsored by The University of Arizona Center for CONSCIOUSNESS STUDIES CONTENTS Welcome . 2-4 Tucson Telephone Numbers . 5 Transportation Services . 5 Pre-Conference Workshop . 7 Conference Overview . 8 Optional Social Events . 8-9 Pre-Conference List . 10-11 Conference Week Schedule Grid . 12-22 INDEX to SESSIONS Plenary . 23-25 Concurrents . .. 26-34 Posters . 35-50 Art/Tech/Health Exhibits & Demos . 51 CCS-TSC Taxonomy and Classifications . 52-53 INDEX to ABSTRACTS Abstracts by Classification . 54-274 East-West Forum Abstracts . 275-300 Additional Abstracts . 301-303 Index to Authors . 304-306 WELCOME Welcome to Toward a Science of Consciousness 2014, the 20th anniversary of the biennial, international interdisciplinary Tucson Conference on the fundamental question of how the brain produces conscious experience . Sponsored and organized by the Center for Consciousness Studies at the University of Arizona, this year’s conference is being held for the first time at the Tucson Marriott University Park Hotel, steps from the main gate of the beautiful campus of the University of Arizona . Covering 380 acres in central Tucson, the campus is a hub of education, concerts, plays, lectures, museums, poetry readings, athletic events, playing on the great grassy mall, and just hanging out . Adjacent to the UA main gate and hotel are over 30 shops, restaurants and pubs along University Boulevard . A short walk in the opposite direction leads to the village setting of 4th Avenue and then to downtown Tucson . Toward a Science of Consciousness (TSC) is the largest and longest-running interdisciplinary conference emphasizing broad and rigorous interdisciplinary approaches to conscious awareness, the nature of existence and our place in the universe .
    [Show full text]
  • Space, Time and Natural Law: a Peircean Look at Smolin's Temporal
    SCIO. Revista de Filosofía, n.º 12, Noviembre de 2016, 143-162, ISSN: 1887-9853 SPACE, TIME AND NATURAL LAW: A PEIRCEAN LOOK AT SMOLIN’S TEMPORAL NATURALISM EL ESPACIO, EL TIEMPO Y LA LEY NATURAL: UN LOOK PEIRCEANO AL NATURALISMO TEMPORAL DE SMOLIN Cornelius de Waala Fechas de recepción y aceptación: 16 de marzo de 2016, 10 de octubre de 2016 Resumen: En su libro Time Reborn y en otros escritos, el físico Lee Smo- lin identifica a Peirce como precursor de su idea de que las leyes naturales evolucionaron; una visión que va en contra de la opinión común dentro de la física de que el tiempo no es real. Después de discutir los argumentos de Smolin sobre la realidad del tiempo, se discuten también dos plan- teamientos defendidos por Smolin –la selección natural cosmológica y la Quantum Energetic Causal Set Theory– en el contexto de la cosmología de Peirce. Se muestra que el enfoque de Peirce proporciona una posible base para una teoría física como la Quantum Energetic Causal Set Theory, abriendo el camino para una cosmología completa que haga justicia a la física contemporánea. Palabras clave: Smolin, cosmología, espacio, tiempo. Abstract: In Time Reborn and elsewhere physicist Lee Smolin identifies Peirce as a precursor to his view that natural laws evolved, a view that runs counter the received opinion within physics that time isn’t real. After dis- cussing Smolin’s arguments for the reality of time, two approaches advo- a Professor of Philosophy at Indiana University-Purdue University Indianapolis. Correspondencia: IU School of Liberal Arts at IUPUI.
    [Show full text]
  • Physics Today
    Physics Today Time, laws, and the future of cosmology Lee Smolin Citation: Physics Today 67(3), 38 (2014); doi: 10.1063/PT.3.2310 View online: http://dx.doi.org/10.1063/PT.3.2310 View Table of Contents: http://scitation.aip.org/content/aip/magazine/physicstoday/67/3?ver=pdfcov Published by the AIP Publishing This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP: 130.58.92.249 On: Thu, 06 Nov 2014 22:06:20 BY STEFAN KABEN IT STARTS WITH ONE Time, laws, and the future of cosmology Lee Smolin To be worthy of the title “scientific,” a law of nature must be testable. But nothing requires a scientific law to be unchanging. s physicists, we have been educated to Every system has available to it a space of possible share a common conception of a law of states or configurations. A point in that space repre- nature. A law, such as one of Newton’s sents a possible state of the system. In the course of laws of motion or the Schrödinger or time, the system traces a curve in the state space as A Einstein equation, is a general statement it passes from state to state. Some dynamical law that tells how large classes of systems change in governs those motions. That is, given an initial state, time. Laws themselves don’t change; they apply it returns a trajectory of states that determines the everywhere in space and for all time.
    [Show full text]
  • On the Embodiment of Space and Time: Triadic Logic, Quantum Indeterminacy and the Metaphysics of Relativity
    On the Embodiment of Space and Time: Triadic logic, quantum indeterminacy and the metaphysics of relativity Timothy Rogers [email protected] Trinity College, University of Toronto September 29, 2016 Abstract (Thesis Statement) Triadic (systemical) logic can provide an interpretive paradigm for understanding how quantum indeterminacy is a consequence of the formal nature of light in relativity theory. This interpretive paradigm is coherent and constitutionally open to ethical and theological interests. In this statement: • Triadic logic refers to a formal pattern that describes systemic (collaborative) processes involving signs that mediate between interiority (individuation) and exteriority (generalized worldview or Umwelt). It is also called systemical logic or the logic of relatives. The term "triadic logic" emphasizes that this logic involves mediation of dualities through an irreducibly triadic formalism. The term "systemical logic" emphasizes that this logic applies to systems in contrast to traditional binary logic which applies to classes. The term "logic of relatives" emphasizes that this logic is background independent (in the sense discussed by Smolin 1). • An interpretive paradigm refers to a way of thinking that generates an understanding through concepts, their inter-relationships and their connections with experience. • Coherence refers to holistic integrity or continuity in the meaning of concepts that form an interpretation or understanding. • Constitutionally open refers to an inherent dependence in principle of an interpretation or understanding on something outside of a specific disipline's discourse or domain of inquiry (epistemic system). Interpretations that are constitutionally open are incomplete in themselves and open to responsive, interdisciplinary discourse and collaborative learning. 1 Lee Smolin, The trouble with physics: The rise of string theory, the fall of a science, what comes next.
    [Show full text]
  • Arxiv:1807.01520V3 [Gr-Qc] 17 Sep 2018
    A Universe that does not know the time Jo˜ao Magueijo1 and Lee Smolin2 1Theoretical Physics Group, The Blackett Laboratory, Imperial College, Prince Consort Rd., London, SW7 2BZ, United Kingdom 2Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo, Ontario N2J 2Y5, Canada (Dated: September 18, 2018) In this paper we propose that cosmological time is a quantum observable that does not commute with other quantum operators essential for the definition of cosmological states, notably the cosmo- logical constant. This is inspired by properties of a measure of time—the Chern-Simons time—and the fact that in some theories it appears as a conjugate to the cosmological constant, with the two promoted to non-commuting quantum operators. Thus, the Universe may be “delocalised” in time: it does not know the time, a property which opens up new cosmological scenarios, as well as invalidating several paradoxes, such as the timelike tower of turtles associated with an omnipresent time line. Alternatively, a Universe with a sharply defined clock time must have an indeterminate cosmological constant. The challenge then is to explain how islands of localized time may emerge, and give rise to localized histories. In some scenarios this is achieved by backward transitions in quantum time, cycling the Universe in something akin to a time machine cycle, with classical flow and quantum ebbing. The emergence on matter in a sea of Lambda probably provides the ballast behind classical behaviour. I. INTRODUCTION dynamical degrees of freedom inside the Universe. With the loss of a preferred external or absolute time, there are diverse clocks which may be used for different purposes.
    [Show full text]