English
Related papers

Related papers: Time and its arrow from quantum geometrodynamics?

200 papers

Our observed Universe has a very strong arrow of time rooted in its low entropy starting point. This low entropy start can be related to various "tuning puzzles" about the early state of the Universe. Here we explore the relationship…

High Energy Physics - Theory · Physics 2022-12-28 Andreas Albrecht , Rose Baunach , Andrew Arrasmith

The nature of time in quantum mechanics is closely related to the use of a complex, rather than say real, Hilbert space. This becomes particularly clear when considering quantum field theory in time dependent backgrounds, such as in…

General Relativity and Quantum Cosmology · Physics 2011-11-03 G. W. Gibbons

Why time is a one-way corridor? What's the origin of the arrow of time? We attribute the thermodynamic arrow of time as the direction of increasing quantum state complexity. Inspired by the work of Nielsen, Susskind and Micadei, we checked…

Quantum Physics · Physics 2017-12-20 Xiao Dong , Ling Zhou

One of the most difficult problems in the foundations of physics is what gives rise to the arrow of time. Since the fundamental dynamical laws of physics are (essentially) symmetric in time, the explanation for time's arrow must come from…

History and Philosophy of Physics · Physics 2021-10-26 Eddy Keming Chen

This paper extends the work of a previous paper [arXiv:1208.2611] on the flow of time, to consider the origin of the arrow of time. It proposes that a `past condition' cascades down from cosmological to micro scales, being realized in many…

General Relativity and Quantum Cosmology · Physics 2013-03-04 George F R Ellis

This paper presents a unified formulation of the origin of the arrow of time in classical and quantum mechanics. We begin with a mechanical analysis of a one-dimensional three-particle system, which provides a concrete example in which…

Statistical Mechanics · Physics 2025-12-19 Shuhei Kobayashi

In a recent paper (arXiv:1412.6000) a general mechanism for emergence of cosmological space-time geometry from a quantum gravity setting was devised and departure from standard dispersion relations for elementary particle were predicted. We…

General Relativity and Quantum Cosmology · Physics 2015-12-16 Ricardo Gallego Torromé , Marco Letizia , Stefano Liberati

We address a long-standing misperception on the gravitational ``arrow of time'', a proposal by Penrose (also known as the ``Weyl-curvature hypothesis") that associates structure formation along timelike directions in which Weyl-curvature…

General Relativity and Quantum Cosmology · Physics 2025-12-03 Roberto A. Sussman , Sebastián Nájera , Fernando A. Pizaña , Juan Carlos Hidalgo

We propose a mathematical model of quantum spacetime as an infinite-dimensional manifold locally homeomorphic to an appropriate Schwartz space. This extends and unifies both the standard function space construction of quantum mechanics and…

Mathematical Physics · Physics 2008-09-19 Manuel Hohmann , Raffaele Punzi , Mattias N. R. Wohlfarth

I present the theoretical evidence which suggests that gravity is an emergent phenomenon like gas dynamics or elasticity with the gravitational field equations having the same status as, say, the equations of fluid dynamics/elasticity. This…

General Relativity and Quantum Cosmology · Physics 2011-07-13 T. Padmanabhan

The gravity is classically formulated as the geometric curvature of the space-time in general relativity which is completely different from the other well-known physical forces. Since seeking a quantum framework for the gravity is a great…

High Energy Physics - Theory · Physics 2014-09-29 Cao H. Nam

In the understanding of the fundamental interactions, the origin of an arrow of time is viewed as problematic. However, quantum field theory has an arrow of causality, which tells us which time direction is the past lightcone and which is…

Quantum Physics · Physics 2020-10-15 John F. Donoghue , Gabriel Menezes

In this paper, we investigate an important issue addressed by several approaches to quantum cosmology, like that based on loop quantum gravity and string theory: the existence of an arrow of time driving the cosmological evolution according…

General Relativity and Quantum Cosmology · Physics 2026-03-25 Carlos Silva , Renan Aragão , Francisco A. Brito

The only widely accepted explanation for the various arrows of time that everywhere and at all epochs point in the same direction is the `past hypothesis': the Universe had a very special low-entropy initial state. We present the first…

General Relativity and Quantum Cosmology · Physics 2014-12-11 Julian Barbour , Tim Koslowski , Flavio Mercati

We revisit the issue of time in quantum geometrodynamics and suggest a quantization procedure on the space of true dynamic variables. This procedure separates the issue of quantization from enforcing the constraints caused by the general…

General Relativity and Quantum Cosmology · Physics 2016-12-21 Warner A. Miller , Arkady Kheyfets

All the laws of physics are time-reversible. Time arrow emerges only when ensembles of classical particles are treated probabilistically, outside of physics laws, and the entropy and the second law of thermodynamics are introduced. In…

Quantum Physics · Physics 2021-03-16 Davi Geiger , Zvi M. Kedem

The relation between the thermodynamical and cosmological arrows of time is usually viewed in the context of the initial conditions of the Universe. It is a necessary but not sufficient condition for ensuring the thermodynamical arrow. We…

Astrophysics · Physics 2018-03-28 A. E. Allahverdyan , V. G. Gurzadyan

The question about the appearance of time in the semiclassical limit of quantum gravity continues to be discussed in the literature. It is believed that a temporal Schrodinger equation for matter fields on the background of a classical…

General Relativity and Quantum Cosmology · Physics 2025-07-24 R. I. Ayala Oña , M. B. Kalmykov , D. P. Kislyakova , T. P. Shestakova

The description of the universe evolving in time according to general relativity is given in comparison with the quantum description of the same universe in terms of semiclassical wave functions. The spacetime geometry is determined by the…

General Relativity and Quantum Cosmology · Physics 2015-12-09 V. E. Kuzmichev , V. V. Kuzmichev

The "problem of time" in canonical quantum gravity refers to the difficulties involved in defining a Hilbert space structure on states -- and local observables on this Hilbert space -- for a theory in which the spacetime metric is treated…

General Relativity and Quantum Cosmology · Physics 2009-12-30 Robert M. Wald