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Related papers: Ultrastatic spacetimes

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We show explicitly that there is particle creation in a static spacetime. This is done by studying the field in a coordinate system based on a physical principle which has recently been proposed. There the field is quantized by decomposing…

High Energy Physics - Theory · Physics 2015-06-26 D. J. Lamb , A. Z. Capri , S. M. Roy

A manifestly covariant equation is derived to describe the second order perturbations in topological defects and membranes on arbitrary curved background spacetimes. This, on one hand, generalizes work on macroscopic strings in Minkowski…

High Energy Physics - Theory · Physics 2019-01-07 V. Kiosses , A. Nicolaidis

This work provides a smooth and everywhere well-defined extension of Bondi-Metzner-Sachs (BMS) supertranslations into the bulk of Minkowski space. The supertranslations lead to physically distinct spacetimes, all isometric to Minkowski…

General Relativity and Quantum Cosmology · Physics 2018-02-20 Friedrich Schöller

We discuss the uniqueness of asymptotically flat and static spacetimes in the $n$-dimensional Einstein-conformal scalar system. This theory potentially has a singular point in the field equations where the effective Newton constant…

General Relativity and Quantum Cosmology · Physics 2021-11-24 Keisuke Izumi , Yoshimune Tomikawa , Tetsuya Shiromizu

It is univocally anticipated that in a theory of quantum gravity, there exist quantum superpositions of semiclassical states of spacetime geometry. Such states could arise for example, from a source mass in a superposition of spatial…

General Relativity and Quantum Cosmology · Physics 2025-01-20 Joshua Foo , Robert B. Mann , Magdalena Zych

The metric perturbation tensor corresponding to a transverse oscillation of spacetime is composed of products of cosines. When averaged over many wavelengths, such a metric may look either Minkowskian or Euclidean at large scales, depending…

General Relativity and Quantum Cosmology · Physics 2007-05-23 N. Redington

De Sitter spacetime can be separated into two parts along two kinds of hypersurfaces and the half-de Sitter spacetimes are covered by the planar and hyperbolic coordinates respectively. Two positive energy theorems were proved previously…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Zhuobin Liang , Xiao Zhang

Some highly speculative and serendipitous ideas that might relate thermodynamics, spacetime, shape and symmetry are brought together. A hypothetical spacetime comprising a pointwise lattice with a fixed metric is considered. If there were…

General Physics · Physics 2007-10-08 Jim McGovern

A generalised equivalence principle is put forward according to which space-time symmetries and internal quantum symmetries are indistinguishable before symmetry breaking. Based on this principle, a higher-dimensional extension of Minkowski…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Dorje C. Brody , Lane P. Hughston

Different approaches to quantum gravity generally predict that the dimension of spacetime at the fundamental level is not 4. The principal tool to measure how the dimension changes between the IR and UV scales of the theory is the spectral…

High Energy Physics - Theory · Physics 2020-10-07 Michał Eckstein , Tomasz Trześniewski

Two questions are investigated by looking successively at classical mechanics, special relativity, and relativistic gravity: first, how is space related with spacetime? The proposed answer is that each given reference fluid, that is a…

General Relativity and Quantum Cosmology · Physics 2018-07-06 Mayeul Arminjon

The difference between the timelike and spacelike meson form factors is analysed in the framework of perturbative QCD with Sudakov effects included. It is found that integrable singularities appear but that the asymptotic behavior is the…

High Energy Physics - Phenomenology · Physics 2009-12-30 T. Gousset , B. Pire

We give a brief overview of the nature of spacetime emerging from string theory. This is radically different from the familiar spacetime of Einstein's relativity. At a perturbative level, the spacetime metric appears as ``coupling…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Gary T. Horowitz

We consider the timelike minimal surface problem in Minkowski spacetimes and show local and global existence of such surfaces having arbitrary dimension $\geq 2$ and arbitrary co-dimension, provided they are initially close to a flat plane.

Differential Geometry · Mathematics 2007-05-23 Paul Allen , Lars Andersson , James Isenberg

The space time that is used in relativistic Quantum Mechanics and Quantum Field Theory is the Minkowski space time. Yet, as pointed out by several scholars this classical space time is incompatible with the Heisenberg Uncertainity…

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

The emergence of the concept of a causal fermion system is revisited and further investigated for the vacuum Dirac equation in Minkowski space. After a brief recap of the Dirac equation and its solution space, in order to allow for the…

Mathematical Physics · Physics 2020-12-15 Marco Oppio

Using the relativistic concept of time dilation we show that a superposition of gravitational potentials can lead to nonunitary time evolution. For sufficiently weak gravitational potentials one can still define, for all intents and…

The formulae of special relativity are developed through the k-calculus with no presumption of a manifold. The metric is determined empirically by the exchange of photons, and the treatment suggests that the exchange of photons seen in…

General Physics · Physics 2007-05-23 Charles Francis

According to the Lorentz transformation and clearly seen from the Minkowski diagram, hyperbolic spacetime motion of a test object relative to a stationary reference frame can be performed in a specific way such that time becomes frozen in…

General Physics · Physics 2011-08-25 Arne Bergstrom

In this essay, dedicated to the one hundredth anniversary of Hermann Minkowski's talk "Space and Time", I argue that physicists should face the issue of the reality of spacetime and worldtubes of physical objects for two reasons. First,…

General Physics · Physics 2012-07-30 Vesselin Petkov
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