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Related papers: Spacetime in the Ultimate Theory

200 papers

Following recent assumptions to unify quantum mechanics and general relativity, the structure of spacetime is suppose to be a consequence of the relations among some fundamental objects, and its concept can be formulated without the…

High Energy Physics - Lattice · Physics 2007-05-23 M. Lorente

Several physical concepts, including the concept of time, are clarified herein by taking into account existing experimental data. In addition, the missing links among these physical concepts are established. This allows us to take another…

General Physics · Physics 2022-10-04 Robert Sadykov

A new speculative model for the expansion of our universe has been under development by the author for the last two decades, which correctly predicts astronomical measurements with no dark matter or dark energy. This new closed model (no…

General Physics · Physics 2010-02-16 Charles B. Leffert

Whether or not space-time is fundamentally discrete is of central importance for the development of the theory of quantum gravity. If the fundamental description of space-time is discrete, typically represented in terms of a graph or…

High Energy Physics - Phenomenology · Physics 2014-03-24 Sabine Hossenfelder

Every spacetime is defined by its metric, the mathematical object which further defines the spacetime curvature. From the relativity principle, we have the freedom to choose which coordinate system to write our metric in. Some coordinate…

General Relativity and Quantum Cosmology · Physics 2021-04-22 Joshua Baines

Despite the obvious utility of the concept, it has often been argued that time does not exist. I take the opposite perspective: let's imagine that time does exist, and the universe is described by a quantum state obeying ordinary…

General Relativity and Quantum Cosmology · Physics 2008-11-25 Sean M. Carroll

This paper explores the status of some notions which are usually associated to time, like datations, chronology, durations, causality, cosmic time and time functions in the Einsteinian relativistic theories. It shows how, even if some of…

General Relativity and Quantum Cosmology · Physics 2013-12-11 Marc Lachieze-Rey

How special (or not) is the epoch we are living in? What is the appropriate reference class for embedding the observations made at the present time? How probable -- or else -- is anything we observe in the fulness of time? Contemporary…

History and Philosophy of Physics · Physics 2020-03-18 Milan M. Ćirković , Amedeo Balbi

In contemporary physics space and time are intertwined entities so that kinematical and dynamical quantities are expressed in the four-dimensional space-time. This formulation seems to contradict our every-day experience and perception…

General Physics · Physics 2023-05-23 Orfeu Bertolami

A deformation of special relativistic kinematics (possible signal of a theory of quantum gravity at low energies) leads to a modification of the notion of spacetime. At the classical level, this modification is required when one considers a…

High Energy Physics - Theory · Physics 2019-12-02 J. M. Carmona , J. L. Cortes , J. J. Relancio

In this letter we briefly investigate the mathematical structure of space-time in the framework of discretization. It is shown that the discreteness of space-time may result in a new mechanical system which differ from the usual quantum…

Quantum Physics · Physics 2010-03-29 An-Wei Zhang

In the History of Ideas, a succession of philosophical and scientific achievements, concerning the concept of space and its dimensionality, were essential to contribute, after a long period, to the theoretical possibility of thinking…

History and Philosophy of Physics · Physics 2024-07-10 Francisco Caruso

Preparing general relativity for quantization in the Hamiltonian approach leads to the `problem of time,' rendering the world fundamentally timeless. One proposed solution is the `thermal time hypothesis,' which defines time in terms of…

History and Philosophy of Physics · Physics 2024-07-30 Eugene Y. S. Chua

Quantum gravity (or quantum spacetime) is to unify general relativity and quantum mechanics into a single theoretical framework and presented as the most important open puzzle in fundamental physics. The development of a microscopic theory…

General Physics · Physics 2025-10-24 Su-Peng Kou

This paper argues against the proposal to draw from current research into a physical theory of quantum gravity the ontological conclusion that spacetime or spatiotemporal relations are not fundamental. As things stand, the status of this…

History and Philosophy of Physics · Physics 2019-03-18 Michael Esfeld

A five-dimensional cosmological theory of gravitation that unifies space, time and velocity is presented

Astrophysics · Physics 2009-11-07 Moshe Carmeli

Ideal rods and clocks are defined as an infinitesimal symmetry of the spacetime. Since no a priori geometric structure is considered, all the possible models of spacetime are obtained.

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. N. Bernal , M. P. Lopez , M. Sanchez

Why is the manifold topology in a spacetime taken for granted? Why do we prefer to use Riemann open balls as basic-open sets, while there also exists a Lorentz metric? Which topology is a best candidate for a spacetime; a topology…

Mathematical Physics · Physics 2019-09-17 Kyriakos Papadopoulos , Fabio Scardigli

A thermo field dynamics approach for calculating the entropy of a spacetime is suggested. It is exemplified through the Rindler spacetime, the Milne spacetime, the Boulware spacetime, and the Minkowski spacetime with a moving mirror that…

General Relativity and Quantum Cosmology · Physics 2015-11-03 Yu-Zhu Chen , Wen-Du Li , Wu-Sheng Dai

We briefly review theories of fuzzy spacetime or with a spacetime cut off, particularising on the author's own model which correctloy predicted the present cosmological model of an accelerating universe and dark energy, and which points to…

General Physics · Physics 2007-05-23 B. G. Sidharth