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Related papers: The nature of the present

200 papers

The conceptual definition and understanding of the nature of time, both qualitatively and quantitatively is of the utmost difficulty and importance, and plays a fundamental role in physics. Physical systems seem to evolve in paths of…

General Relativity and Quantum Cosmology · Physics 2015-01-14 Francisco S. N. Lobo

A review of some basic facts of classical dynamics shows that time, or precisely duration, is redundant as a fundamental concept. Duration and the behaviour of clocks emerge from a timeless law that governs change.

General Relativity and Quantum Cosmology · Physics 2009-03-23 Julian Barbour

Contrary to the informed consensus, time travel implies spontaneity (as distinct from chance) so that time travel can only be of the second kind.

General Physics · Physics 2011-07-22 C. K. Raju

The world is four-dimensional according to fundamental physics, governed by basic laws that operate in a spacetime that has no unique division into space and time. Yet our subjective experience is divided into present, past, and future.…

General Relativity and Quantum Cosmology · Physics 2009-11-10 James B. Hartle

We review the idea, due to Einstein, Eddington, Hoyle and Ballard, that time is a subjective label, whose primary purpose is to order events, perhaps in a higher-dimensional universe. In this approach, all moments in time exist…

General Physics · Physics 2015-05-13 Paul S. Wesson

Are time-travels possible? is the past still existing? and is the future already existing? We try to give an answer to these an other questions concerning the properties of time and the close connection (but deep physical difference)…

General Relativity and Quantum Cosmology · Physics 2025-07-09 Maurizio Gasperini

A closer look (with hindsight) at Newtonian and relativistic kinematics reveals two things. Not surprisingly, Newtonian time remains the empty and artificial - albeit useful - figment it is known to be. Quite unexpectedly however it turns…

General Physics · Physics 2007-05-23 Chris Leemann

The Block Universe idea, representing spacetime as a fixed whole, suggests the flow of time is an illusion: the entire universe just is, with no special meaning attached to the present time. This view is however based on time-reversible…

General Relativity and Quantum Cosmology · Physics 2009-11-11 George F. R. Ellis

This paper proposes an abstract mathematical frame for describing some features of cognitive and biological time. We focus here on the so called "extended present" as a result of protentional and retentional activities (memory and…

Other Quantitative Biology · Quantitative Biology 2012-04-09 Giuseppe Longo , Maël Montévil

In this work we present an epistemic analysis of time phenomenon using the mathematical machinery of information theory and modular theory. By adopting limited commitment to the ontology of time evolution, and instead by mainly relying on…

History and Philosophy of Physics · Physics 2022-06-09 Farhang Hadad Farshi , Silvia DeBianchi

I dissent from the standard assertion of a "Two Times Problem," in which physical time is taken as being at odds with the human sense of a "flow of time." I provide a brief overview of the case to be made for the contrary view: namely, that…

History and Philosophy of Physics · Physics 2023-07-18 Ruth E. Kastner

This paper investigates the mathematical representation of time in physics. In existing theories time is represented by the real numbers, hence their formal properties represent properties of time: these are surveyed. The central question…

History and Philosophy of Physics · Physics 2015-08-27 Nick Huggett

Theories in physics usually do not address ``the present''or ``the now''. However, they usually have a precise notion of an ``instant'' (or state). I review how this notion appears in relational point mechanics and how it suffices to…

History and Philosophy of Physics · Physics 2015-06-02 Domenico Giulini

The meaning of instantaneous action at a distance is elucidated. It is shown that the absence of a medium to transmit action (usually referred to as AAD in the literature) and instantaneous action are not identical. Since the term…

General Physics · Physics 2007-05-23 S. C. Tiwari

It seems natural to ask why the universe exists at all. Modern physics suggests that the universe can exist all by itself as a self-contained system, without anything external to create or sustain it. But there might not be an absolute…

History and Philosophy of Physics · Physics 2018-06-06 Sean M. Carroll

Theoretical physics is the search for simple and universal mathematical descriptions of the natural world. In contrast, much of modern biology is an exploration of the complexity and diversity of life. For many, this contrast is prima facie…

Biological Physics · Physics 2024-01-23 William Bialek

In this paper I argue that the fundamental aspect of our notion of time is that it defines an order relation, be it a total order relation between configurations of the world or just a partial order relation between events. This position is…

History and Philosophy of Physics · Physics 2024-10-11 Álvaro Mozota Frauca

The quantum-mechanical description of the world, including human observers, makes substantial use of entanglement. In order to understand this, we need to adopt concepts of truth, probability and time which are unfamiliar in modern…

Quantum Physics · Physics 2013-04-23 Anthony Sudbery

After a short review on the use of time in various branches of physics, I suggest to change the interpretation of time, from a duration to a cut. A reassessment of terminology is also required to avoid meaning traps. I also address the…

General Physics · Physics 2026-05-05 Luigi Foschini

Some unique source -- the world, W -- must underlie all the information realized in the universe throughout time. Perceived reality, R, is a progressively emerging representation of W in the form of the geometrical universe. Time…

General Physics · Physics 2009-03-11 Martin A. Green