In Causality Principle As the Framework to Contextualize Time in Modern Physics
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Arxiv:2103.15570V2 [Physics.Hist-Ph] 22 Jun 2021 to This Article in Its Purpose and Content
An Analysis of the Concept of Inertial Frame Boris Čulina Department of Mathematics University of Applied Sciences Velika Gorica Zagrebačka cesta 5, 10410 Velika Gorica, Croatia e-mail: [email protected] Abstract. The concept of inertial frame of reference is analysed. It has been shown that this fundamental concept of physics is not clear enough. A definition of inertial frame of reference is proposed which expresses its key inherent property. The definition is operational and powerful. Many other properties of inertial frames follow from the definition or it makes them plausible. In particular, the definition shows why physical laws obey space and time symmetries and the principle of relativity, it resolves the problem of clock synchronization and the role of light in it, as well as the problem of the geometry of inertial frames. keywords: inertial frame of reference, space and time symmetries, the principle of relativity, clock synchronization, physical geometry The concept of inertial frame is a fundamental concept of physics. The opinion of the author is that not enough attention has been paid to such a significant concept, not only in textbooks, but also in the scientific literature. In the scientific literature, many particular issues related to the concept of inertial frame have been addressed, but, as far as the author is aware, a sys- tematic analysis of this concept has not been made. DiSalle’s article [DiS20] in the Stanford Encyclopedia of Philosophy gives an overview of the histori- cal development of the concept of an inertial frame as an essential part of the historical development of physics. -
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. -
Principle of Relativity in Physics and in Epistemology Guang-Jiong
Principle of Relativity in Physics and in Epistemology Guang-jiong Ni Department of Physics, Fudan University, Shanghai 200433,China Department of Physics , Portland State University, Portland,OR97207,USA (Email: [email protected]) Abstract: The conceptual evolution of principle of relativity in the theory of special relativity is discussed in detail . It is intimately related to a series of difficulties in quantum mechanics, relativistic quantum mechanics and quantum field theory as well as to new predictions about antigravity and tachyonic neutrinos etc. I. Introduction: Two Postulates of Einstein As is well known, the theory of special relativity(SR) was established by Einstein in 1905 on two postulates (see,e.g.,[1]): Postulate 1: All inertial frames are equivalent with respect to all the laws of physics. Postulate 2: The speed of light in empty space always has the same value c. The postulate 1 , usually called as the “principle of relativity” , was accepted by all physicists in 1905 without suspicion whereas the postulate 2 aroused a great surprise among many physicists at that time. The surprise was inevitable and even necessary since SR is a totally new theory out broken from the classical physics. Both postulates are relativistic in essence and intimately related. This is because a law of physics is expressed by certain equation. When we compare its form from one inertial frame to another, a coordinate transformation is needed to check if its form remains invariant. And this Lorentz transformation must be established by the postulate 2 before postulate 1 can have quantitative meaning. Hence, as a metaphor, to propose postulate 1 was just like “ to paint a dragon on the wall” and Einstein brought it to life “by putting in the pupils of its eyes”(before the dragon could fly out of the wall) via the postulate 2[2]. -
Reconstructing William Craig Explanation of Absolute Time Based on Islamic Philosophy
Reconstructing William Craig Explanation of Absolute Time Based on Islamic Philosophy M. S. Kavyani (1), H. Parsania (2), and H. Razmi (3) Department of Philosophy of Physics, Baqir al Olum University, 37185-787, Qom, I. R. Iran. (2) Permanent Address: Department of Social Sciences, Tehran University, Tehran, I. R. Iran. (3) Permanent Address: Department of Physics, University of Qom, Qom, I. R. Iran. (1) [email protected] (2) [email protected] (3) [email protected] Abstract After the advent of the theory of special relativity, the existence of an absolute time in nature was rejected in physics society. In recent decades, William Craig has endeavored to offer an interpretation of empirical evidences corresponding to theory of relativity with the preservation of an absolute time. His strategy is based on two viewpoints including dynamical theory of time and the Eminent God’s temporal being. After considering and criticizing these two viewpoints, using the well-known overall substantial motion of nature in Islamic philosophy and thus the realization of a general time for all the nature, we have tried to reconstruct Craig argument for an absolute time. Although Craig has considered some evidences from modern physics reasoning on an absolute time, the special advantage of the approach considered here is in this fact that it connects better the existing gap between the metaphysics and the physics of the argument. Keywords: Absolute time; Theory of relativity; William Craig; The dynamical time theory; Islamic Philosophy; Nature overall substantial motion; General time Introduction In classical mechanics, the absolute universal time was considered as the measure of the events chronology and a parameter for determining their priority, posteriority, and simultaneity. -
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. -
Relationalism About Mechanics Based on a Minimalist Ontology of Matter
Relationalism about mechanics based on a minimalist ontology of matter Antonio Vassallo,∗ Dirk-André Deckert,† Michael Esfeld‡ Accepted for publication in European Journal for Philosophy of Science This paper elaborates on relationalism about space and time as motivated by a minimalist ontology of the physical world: there are only matter points that are individuated by the distance relations among them, with these re- lations changing. We assess two strategies to combine this ontology with physics, using classical mechanics as example: the Humean strategy adopts the standard, non-relationalist physical theories as they stand and interprets their formal apparatus as the means of bookkeeping of the change of the distance relations instead of committing us to additional elements of the on- tology. The alternative theory strategy seeks to combine the relationalist ontology with a relationalist physical theory that reproduces the predictions of the standard theory in the domain where these are empirically tested. We show that, as things stand, this strategy cannot be accomplished without compromising a minimalist relationalist ontology. Keywords: relationalism, parsimony, atomism, matter points, ontic structural realism, Humeanism, classical mechanics Contents 1 From atomism to relationalism about space and time 2 2 From ontology to physics: two strategies 11 ∗Université de Lausanne, Faculté des lettres, Section de philosophie, 1015 Lausanne, Switzerland. E- arXiv:1609.00277v1 [physics.hist-ph] 1 Sep 2016 mail: [email protected] †Ludwig-Maximilians-Universität -
Newtonian Space-Time
L1lCU .. l.HC I..i.~UU Ul 411 LU •••..)C .lU,)I.~1.lJ.LLol.L.LI".Uu..) ,)t'IA •••.••,•.) u.I...J.y v....I.UUU6.l..L1." V.L u.~ ...1...1••.• 10cIIs Of all pQHible eVeJlts; it is called "sp:l.ce-time." (3) The instant.l!!::ousthree-dimensional spaces, which so far as (2) goes are entirely separ.lte, form p:lrt of a luger connected, structure: sp:lce-time is, intrinsicallr, :z fOllr-dimensional real affine space-that is, it possesses a a notion of "str:light line," having the same properties in respect of inter- section (and. so also parallelism) as in a Euclidean space of four di- y REMARKS TODAY AND TO};!OR.~.OW WILL BE BASED UPON A RATHER mensions. (The stmight lines of space-time are to be thought of as repre- lengthy paper, written witl1severl1 simultaneous objectives: senting all F{)ssibleuniform rectilinear lIIotiollS.2) Moreover, the natural M. (I) To cast light upon the issues involved in a celebrated pass:lge of intel- projection of space-time upon T (assigning to every possible event its lectu:ll history, and incidentally to clarify some of the purely historical cir- "epoch" or "date") is an :lffine mapping; :lnd the Euclide:ln structures of cumstances; the insontar.eous spaces :lre compatible with their :lffine structures as the ( 2) By elucidating those is'sues, to help furnish insight on related questions of fibersof this ffi3.pping. current interest; The technicalities of this :l.ccountneed not too much concern those to whom they (3) To promote an attitude tow:lrd philosophical questions that was a prevalent :lreunfa.miliar; but it is important to remark that the structure required by (3), one in the seventeenth century, th3.tseems to me sound and admirable, and which I shall refer to as the "kinematical connection" of space-time, and which th:lt seems not to be prewaLenttoday. -
Can Spacetime Help Settle Any Issues in Modern Philosophy?∗
Can Spacetime Help Settle Any Issues in Modern Philosophy?∗ Presented at the Issues in Modern Philosophy Conference at NYU November 10-11 2006 Nick Huggett Philosophy, UIC December 7, 2006 1 Introduction Deciding what to talk about in this paper was a challenge; perhaps contemporary phi- losophy offers no more possible topics to choose from than any of the individual figures considered over these two days, but what to present that might connect the historical pa- pers with contemporary philosophy? How to say something that might be informative and substantive and useful to an audience which likely comes from a historical background? One option was to discuss philosophical issues concerning contemporary spacetime physics – quantum gravity and string theory say. While that approach might show something of how philosophy continues to engage with emerging science, the danger is that attempts to relate such issues to historical concerns will be forced. I’ve opted instead to discuss a few influential ideas about how twentieth century math- ematics and philosophy can help understand and resolve early modern questions about the nature of space and time. In part I’ll be offering a map of the issues; I’ll be covering quite a lot of ground in a small time, but presumably it’s not entirely new to this audience. To be substantive as well as informative, I want to engage with the ideas I discuss. In particular, (i) I want to explore the limits of the mathematical theory of spacetime (more generally, differential geometry) as an analytical tool for interpreting early modern thought. -
Newton and Leibniz on Space and Time
Newton and Leibniz on Space and Time Jeremy Safran and Jack Kissel Introduction • Can you explain the concept of motion without the notion of space and/or time? – Both Leibniz and Newton’s theories of space and time are rooted in observations of change (e.g. motion). • What is space and time? Are they real substances in the world? Can a single object or event have an absolute space or time, or do space and time rely on relational properties between multiple objects or events? A Few Definitions • Relativism - Leibniz’s theory on space and time • Absolutism – Newton’s theory on space and time • Plenum – a space every part of which is full of matter, which included air and ether • Void – space that contains no matter • Sensory organs – the tools with which we perceive the world. • Sensorium – the seat of sensation where an organism experiences and interprets the environment within which it lives Relativism • First, what are space and time? Are they real substances in the world or simply relational properties between objects and events? • “I hold space to be something merely relative… as an order of coexistences, as time is an order of successions” (Leibniz, L111.4, AW 297b). • For example: If the entire universe were moved 3 inches or 3 seconds from where it actually is, nothing in the universe would change in any significant (relative) way Absolutism • “Absolute space, in its own nature, without relation to anything external, always remains similar and immovable” (Newton, AW 285) • Humans can only observe relative space and time, but absolute space and time must presuppose the relative. -
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. -
The Universe Be (Before Einstein)
ACTIVITY ONE: NOVEMBER 7 THE UNIVERSE B.E. (BEFORE EINSTEIN) On November 7, 2014, Interstellar, a saga of courage, sacrifice, desperation and hope, will challenge moviegoers to think about the radical ways a changing Earth and the need to address its changes might challenge our daily ACTIVITY OVERVIEW: ACTIVITY GUIDELINES lives and the concepts that shape our existence. This film explores the often-startling aspects of the fabric of the universe, as understood by modern scientists. Interstellar will introduce you to scientific concepts that may These thought-provoking supplemental activities are designed to introduce the concept of relativity, and to give boggle your mind. In order to understand and appreciate those concepts, become familiar with the scientific ideas students a broader and deeper understanding of some of the fascinating science behind Interstellar. Use these activities introduced in these activities. as an introduction to the movie and its concepts, and then see the movie together (talk to your PTA!) or have students see the movie with their families and friends before embarking on post-movie discussions about the intriguing concepts and questions the movie raises. PART 1 It’s helpful to know how scientists understood motion through space for hundreds of years. Things like time ACTIVITY ONE: ACTIVITY TWO: ACTIVITY THREE: and distance were absolute: the same everywhere for THE UNIVERSE B.E. (BEFORE EINSTEIN) IT’S ALL RELATIVE CONCEPTUAL CLOCKS On November 7, 2014, Interstellar, a saga of courage, sacrifice, desperation and hope, will challenge moviegoers The universe we know and as depicted in Interstellar has a history of changed and challenging scientific understandings. -
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