Open Questions Regarding the Arrow of Time Sep09
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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. -
The Philosophy and Physics of Time Travel: the Possibility of Time Travel
University of Minnesota Morris Digital Well University of Minnesota Morris Digital Well Honors Capstone Projects Student Scholarship 2017 The Philosophy and Physics of Time Travel: The Possibility of Time Travel Ramitha Rupasinghe University of Minnesota, Morris, [email protected] Follow this and additional works at: https://digitalcommons.morris.umn.edu/honors Part of the Philosophy Commons, and the Physics Commons Recommended Citation Rupasinghe, Ramitha, "The Philosophy and Physics of Time Travel: The Possibility of Time Travel" (2017). Honors Capstone Projects. 1. https://digitalcommons.morris.umn.edu/honors/1 This Paper is brought to you for free and open access by the Student Scholarship at University of Minnesota Morris Digital Well. It has been accepted for inclusion in Honors Capstone Projects by an authorized administrator of University of Minnesota Morris Digital Well. For more information, please contact [email protected]. The Philosophy and Physics of Time Travel: The possibility of time travel Ramitha Rupasinghe IS 4994H - Honors Capstone Project Defense Panel – Pieranna Garavaso, Michael Korth, James Togeas University of Minnesota, Morris Spring 2017 1. Introduction Time is mysterious. Philosophers and scientists have pondered the question of what time might be for centuries and yet till this day, we don’t know what it is. Everyone talks about time, in fact, it’s the most common noun per the Oxford Dictionary. It’s in everything from history to music to culture. Despite time’s mysterious nature there are a lot of things that we can discuss in a logical manner. Time travel on the other hand is even more mysterious. -
Chaos, Dissipation, Arrow of Time, in Quantum Physics I the National Institute of Standards and Technology Was Established in 1988 by Congress to "Assist
Chaos, Dissipation, Arrow of Time, in Quantum Physics i The National Institute of Standards and Technology was established in 1988 by Congress to "assist industry in the development of technology . needed to improve product quality, to modernize manufacturing processes, to ensure product reliability . and to facilitate rapid commercialization . of products based on new scientific discoveries." NIST, originally founded as the National Bureau of Standards in 1901, works to strengthen U.S. industry's competitiveness; advance science and engineering; and improve public health, safety, and the environment. One of the agency's basic functions is to develop, maintain, and retain custody of the national standards of measurement, and provide the means and methods for comparing standards used in science, engineering, manufacturing, commerce, industry, and education with the standards adopted or recognized by the Federal Government. As an agency of the U.S. Commerce Department's Technology Administration, NIST conducts basic and applied research in the physical sciences and engineering and performs related services. The Institute does generic and precompetitive work on new and advanced technologies. NIST's research facilities are located at Gaithersburg, MD 20899, and at Boulder, CO 80303. Major technical operating units and their principal activities are listed below. For more information contact the Public Inquiries Desk, 301-975-3058. Technology Services Manufacturing Engineering Laboratory • Manufacturing Technology Centers Program • Precision -
In the Experiments in Which Alpha-Activity Was Measured Using Collimators Directed at East and West
Volume 1 PROGRESS IN PHYSICS January, 2010 “The Arrow of Time” in the Experiments in which Alpha-Activity was Measured Using Collimators Directed at East and West Simon E. Shnoll, Ilya A. Rubinsteiny, and Nikolai N. Vedenkiny Department of Physics, Moscow State University, Moscow 119992, Russia Inst. of Theor. and Experim. Biophysics, Russian Acad. of Sci., Pushchino, Moscow Region, 142290, Russia Puschino State University, Prospect Nauki 3, Pushchino, Moscow Region, 142290, Russia ySkobeltsin’s Institute of Nuclear Physics, Moscow State University, Moscow 119991, Russia E-mail: [email protected] In our previous paper (Shnoll and Rubinstein, Progress in Physics, 2009, v. 2, 83–95), we briefly reported about a phenomenon, which can be called the “arrow of time”: when we compared histograms constructed from the results of 239-Pu alpha-activity measurements that were obtained using West- and East-directed collimators, daytime series of the “eastern” histograms were similar to the inverted series of the following night, whereas daytime series of the “western” histograms resembled the inverted series of the preceding night. Here we consider this phenomenon in more detail. 1 Introduction As follows from all our past results, the fine structure of the spectrum of amplitude fluctuations (the shape of the corre- sponding histograms) is determined by the motion (orienta- tion) of the object studied (the laboratory) in relation to spa- tial inhomogeneities [2]. The spatial pattern (arrangement in space) of these inhomogeneities is stable: as the Earth ro- tates about its axis and moves along the circumsolar orbit, similar histogram shapes are realized repeatedly with the cor- responding periods (daily, near-monthly, yearly) [3, 4]. -
A Measure of Change Brittany A
University of South Carolina Scholar Commons Theses and Dissertations Spring 2019 Time: A Measure of Change Brittany A. Gentry Follow this and additional works at: https://scholarcommons.sc.edu/etd Part of the Philosophy Commons Recommended Citation Gentry, B. A.(2019). Time: A Measure of Change. (Doctoral dissertation). Retrieved from https://scholarcommons.sc.edu/etd/5247 This Open Access Dissertation is brought to you by Scholar Commons. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Time: A Measure of Change By Brittany A. Gentry Bachelor of Arts Houghton College, 2009 ________________________________________________ Submitted in Partial Fulfillment of the Requirements For the Degree of Doctor of Philosophy in Philosophy College of Arts and Sciences University of South Carolina 2019 Accepted by Michael Dickson, Major Professor Leah McClimans, Committee Member Thomas Burke, Committee Member Alexander Pruss, Committee Member Cheryl L. Addy, Vice Provost and Dean of the Graduate School ©Copyright by Brittany A. Gentry, 2019 All Rights Reserved ii Acknowledgements I would like to thank Michael Dickson, my dissertation advisor, for extensive comments on numerous drafts over the last several years and for his patience and encouragement throughout this process. I would also like to thank my other committee members, Leah McClimans, Thomas Burke, and Alexander Pruss, for their comments and recommendations along the way. Finally, I am grateful to fellow students and professors at the University of South Carolina, the audience at the International Society for the Philosophy of Time conference at Wake Forest University, NC, and anonymous reviewers for helpful comments on various drafts of portions of this dissertation. -
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. -
The Deadly Affairs of John Figaro Newton Or a Senseless Appeal to Reason and an Elegy for the Dreaming
The deadly affairs of John Figaro Newton or a senseless appeal to reason and an elegy for the dreaming Item Type Thesis Authors Campbell, Regan Download date 26/09/2021 19:18:08 Link to Item http://hdl.handle.net/11122/11260 THE DEADLY AFFAIRS OF JOHN FIGARO NEWTON OR A SENSELESS APPEAL TO REASON AND AN ELEGY FOR THE DREAMING By Regan Campbell, B.F.A. A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Fine Arts in Creative Writing University of Alaska Fairbanks May 2020 APPROVED: Daryl Farmer, Committee Chair Leonard Kamerling, Committee Member Chris Coffman, Committee Member Rich Carr, Chair Department of English Todd Sherman, Dean College of Liberal Arts Michael Castellini, Dean of the Graduate School Abstract Are you really you? Are your memories true? John “Fig” Newton thinks much the same as you do. But in three separate episodes of his life, he comes to see things are a little more strange and less straightforward than everyone around him has been inured to the point of pretending they are; maybe it's all some kind of bizarre form of torture for someone with the misfortune of assuming they embody a real and actual person. Whatever the case, Fig is sure he can't trust that truth exists, and over the course of his many doomed relationships and professional foibles, he continually strives to find another like him—someone incandescent with rage, and preferably, as insane and beautiful as he. i Extracts “Whose blood do you still thirst for? But sacred philosophy will shackle your success, for whatsoever may be your momentary triumph or the disorder of this anarchy, you will never govern enlightened men. -
SPACE, TIME, and (How They) MATTER: a Discussion of Some Metaphysical Insights About the Nature of Space and Time Provided by Our Best Fundamental Physical Theories
SPACE, TIME, AND (how they) MATTER: A Discussion of Some Metaphysical Insights about the Nature of Space and Time Provided by Our Best Fundamental Physical Theories Valia Allori Northern Illinois University Forthcoming in: J. Statchel, G.C. Ghirardi (eds.). Space, Time, and Frontiers of Human Understanding. Springer-Verlag Abstract This paper is a brief (and hopelessly incomplete) non-standard introduction to the philosophy of space and time. It is an introduction because I plan to give an overview of what I consider some of the main questions about space and time: Is space a substance over and above matter? How many dimensions does it have? Is space-time fundamental or emergent? Does time have a direction? Does time even exist? Nonetheless, this introduction is not standard because I conclude the discussion by presenting the material with an original spin, guided by a particular understanding of fundamental physical theories, the so-called primitive ontology approach. 1. Introduction Scientific realists believe that our best scientific theories could be used as reliable guides to understand what the world is like. First, they tell us about the nature of matter: for instance, matter can be made of particles, or two-dimensional strings, or continuous fields. In addition, whatever matter fundamentally is, it seems there is matter in space, which moves in time. The topic of this paper is what our best physical theories tell us about the nature of space and time. I will start in the next section with the traditional debate concerning the question of whether space is itself a substance or not. -
110508NU-Ep511-Yellow Script
“Arrow of Time” #511/Ep. 90 Written by Ken Sanzel Directed by Ken Sanzel Production Draft – 10/17/08 Rev. FULL Blue – 10/30/08 Rev. Pink – 11/4/08 Rev. Yellow – 11/5/08 (Pages: 41,46,50,55.) SCOTT FREE in association with CBS PARAMOUNT NETWORK TELEVISION, a division of CBS Studios. © Copyright 2008 CBS Paramount Network Television. All Rights Reserved. This script is the property of CBS Paramount Network Television and may not be copied or distributed without the express written permission of CBS Paramount Network Television. This copy of the script remains the property of CBS Paramount Network Television. It may not be sold or transferred and must be returned to: CBS Paramount Network Television Legal Affairs 4024 Radford Avenue Administration Bldg., Suite 390, Studio City, CA 91604 THE WRITING CREDITS MAY OR MAY NOT BE FINAL AND SHOULD NOT BE USED FOR PUBLICITY OR ADVERTISING PURPOSES WITHOUT FIRST CHECKING WITH TELEVISION LEGAL DEPARTMENT. “Arrow of Time” Ep. #511 – Production Draft: Rev. Yellow – 11/5/08 SCRIPT REVISION HISTORY COLOR DATE PAGES WHITE 10/17/08 (1-57) REV. FULL BLUE 10/30/08 (1-57) REV. PINK 11/4/08 (2,3,4,6,7,18,19,20,27,33, 34,39,41,42,49,50,51,55.) REV. YELLOW 11/5/08 (41,46,50,55.) “Arrow of Time” Ep. #511 – Production Draft: Rev. FULL Blue – 10/30/08 CAST LIST DON EPPES CHARLIE EPPES ALAN EPPES DAVID SINCLAIR LARRY FLEINHARDT AMITA RAMANUJAN COLBY GRANGER NIKKI BETANCOURT LIZ WARNER ROBIN BROOKS BUCK WINTERS RAFE LANSKY GRAY McCLAUGHLIN JOE THIBODEAUX * DEANNE DRAKE TOBY TIM PYNCHON SECOND MARSHAL “Arrow of Time” Ep. -
The Nature and Origin of Time-Asymmetric Spacetime Structures*
The nature and origin of time-asymmetric spacetime structures* H. D. Zeh (University of Heidelberg) www.zeh-hd.de Abstract: Time-asymmetric spacetime structures, in particular those representing black holes and the expansion of the universe, are intimately related to other arrows of time, such as the second law and the retardation of radiation. The nature of the quantum ar- row, often attributed to a collapse of the wave function, is essential, in particular, for understanding the much discussed "black hole information loss paradox". However, this paradox assumes a new form and might not even occur in a consistent causal treatment that would prevent the formation of horizons and singularities. A “master arrow”, which combines all arrows of time, does not have to be identified with the direction of a formal time parameter that serves to define the dynamics as a succes- sion of global states (a trajectory in configuration or Hilbert space). It may even change direction with respect to a fundamental physical clock, such as the cosmic expansion parameter if this was formally extended either into a future contraction era or to nega- tive "pre-big-bang" values. 1 Introduction Since gravity is attractive, most gravitational phenomena are asymmetric in time: ob- jects fall down or contract under the influence of gravity. In General Relativity, this asymmetry leads to drastically asymmetric spacetime structures, such as future hori- zons and future singularities as properties of black holes. However, since the relativistic and nonrelativistic laws of gravitation are symmetric under time reversal, all time asymmetries must arise as consequences of specific (only seemingly "normal") initial conditions, for example a situation of rest that can be prepared by means of other ar- * arXiv:1012.4708v11. -
Time Really Exists! the Evolving Block Universe Volume 7
Time really exists! Volume 7 The evolving block universe Summer 2014 George Ellis journal homepage Department of Mathematics, University of Cape Town, Rondebosch 7701, Cape www.euresisjournal.org Town, South Africa. [email protected] Abstract My starting point is the question, did it make sense for the Planck team to announce the present age of the universe? This talk will propose that it did, because spacetime is an evolving block universe, with the present being the future boundary of a spacetime which steadily extends into the future as time progresses. The present separates the past (which already exists) from the future (which does not yet exist, and is indeterminate because of foundational quantum uncertainty). There are some technical aspects to this namely (1) simultaneity has no physical import, it is a purely psychological construct, (2) one can define unique surfaces of constant time in a non-local geometric way(and show how this relates to the standard ADM formalism), (3) this proposal solves the chronology protection problem (it prevents existence of closed timelike lines). In this context, (4) the arrow of time is distinguished from the direction of time, which is non-locally defined in the evolving block universe context. 1. Prolog There are fossils in the Karoo National Park, South Africa, from amazing extinct wildlife that once thrived in the ancient Karoo during the Late Permian Period. The curator explained as we walked round, \That the skeleton is 255 million and 23 years old!" Amazed, we asked how he knew this. He said \When I came here 23 years ago, it was 255 million years old". -
The Arrow of Time, the Nature of Spacetime, and Quantum Measurement
The arrow of time, the nature of spacetime, and quantum measurement George F R Ellis Mathematics Department, University of Cape Town. October 7, 2011 Abstract This paper extends the work of a previous paper [arXiv:1108.5261v3] on top- down causation and quantum physics, to consider the origin of the arrow of time. It proposes that a ‘past condition’cascades down from cosmological to micro scales, being realised in many microstructures and setting the arrow of time at the quantum level by top-down causation. This physics arrow of time then propagates up, through underlying emergence of higher level structures, to geology, astronomy, engineering, and biology. The appropriate space-time picture to view all this is an emergent block universe (‘EBU’), that recognizes the way the present is di¤erent from both the past and the future. This essential di¤erence is the ultimate reason the arrow of time has to be the way it is. A bonus of this view, entailing the ongoing extension of spacetime as time ‡ows on, is that closed timelike lines are naturally prevented (spacetime singularities will block them o¤). A conclusion of this view is that the process of state vector reduction is central to the ‡ow of time, and is not restricted to laboratory setitngs or any formal process of observation. Contents 1 Quantum theory and the arrow of time 2 2 Foundations 3 2.1 Quantumdynamics............................... 3 2.2 The context: the hierarchy of the structure . 4 2.3 Inter level relations . 4 2.4 Thecentralproposal .............................. 6 3 The arrow of time 7 3.1 Theissue ...................................