English
Related papers

Related papers: Electrodynamics with a Future Conformal Horizon

200 papers

We consider modifications to the Friedmann equation motivated by recent proposals along these lines pursuing an explanation to the observed late time acceleration. Here we show those modifications can be framed within a theory with…

Astrophysics · Physics 2014-10-13 Luis P. Chimento , Ruth Lazkoz

On spacetimes that are not time orientable we construct a U(1) bundle to measure the twisting of the time axis. This single assumption, and simple construction, gives rise to Maxwell's equations of electromagnetism, the Lorentz force law…

General Physics · Physics 2024-01-03 Mark J. Hadley

In this work we consider a family of cosmological models featuring future singularities. This type of cosmological evolution is typical of dark energy models with an equation of state violating some of the standard energy conditions (e.g.…

General Relativity and Quantum Cosmology · Physics 2016-12-21 Jose Beltran Jimenez , Ruth Lazkoz , Diego Saez-Gomez , Vincenzo Salzano

A holographic correspondence between data on horizon and space-time physics is investigated. We find similarities with the AdS/CFT correspondence, based on the observation that the optical metric near the horizon describes a Euclidean…

High Energy Physics - Theory · Physics 2014-11-18 Ivo Sachs , Sergey N. Solodukhin

We report on some advances made in the problem of singularities in general relativity. First is introduced the singular semi-Riemannian geometry for metrics which can change their signature (in particular be degenerate). The standard…

Differential Geometry · Mathematics 2013-09-20 Ovidiu Cristinel Stoica

We show that Parity-time symmetry in matching electric permittivity to magnetic permeability can be established by considering an effective Parity operator involving both mirror symmetry and coupling between electric and magnetic fields.…

Optics · Physics 2015-08-05 James Gear , Fu Liu , S. T. Chu , Stefan Rotter , Jensen Li

We investigate the existence of action for both the electric and magnetic sectors of Galilean Electrodynamics using Helmholtz conditions. We prove the existence of unique action in magnetic limit with the addition of a scalar field in the…

High Energy Physics - Theory · Physics 2019-11-13 Kinjal Banerjee , Rudranil Basu , Akhila Mohan

Intensities in high-resolution phase-contrast images from electron microscopes build up discretely in time by detecting single electrons. A wave description of pulse-like coherent-inelastic interaction of an electron with matter is detailed…

Materials Science · Physics 2024-04-23 Christian Kisielowski , Petra Specht , Joerg R. Jinschek , Stig Helveg

Maxwell's equations are valid only in Lorentz frame i.e. in inertial frame where the Einstein synchronization procedure is used to assign values of the time coordinate. Einstein time order must be applied and kept in consistent way in both…

Accelerator Physics · Physics 2018-08-24 Evgeny Saldin

We consider issues related to the conformal mapping between the Einstein and Jordan frames in f(R) cosmology. We consider the impact of the conformal transformation on the gauge of a perturbed system and show that unless the system is…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Iain A. Brown , Amir Hammami

We establish an exact bidirectional map between interior Friedmann density of a collapsing star and exterior static spherically symmetric metric in generalized Oppenheimer-Snyder collapse. This reduces Einstein's differential…

General Relativity and Quantum Cosmology · Physics 2026-05-12 H. Khodabakhshi , Zhi-Chao Li , H. Lu , F. Shojai

As soon as an interaction between holographic dark energy and dark matter is taken into account, the identification of IR cutoff with Hubble radius $H^{-1}$, in flat universe, can simultaneously drive accelerated expansion and solve the…

High Energy Physics - Theory · Physics 2010-01-06 Ahmad Sheykhi

This is a companion article to `Using massless fields for observing black hole features in the collapsed phase of Euclidean dynamical triangulations' [1]. It clarifies a singular co\"{o}rdinate transformation of an $SO(4)$ invariant metric…

General Relativity and Quantum Cosmology · Physics 2024-12-18 Jan Smit

We study the gravitational collapse in five-dimensional de Sitter (dS) spacetime and discuss the existence of the conformal boundaries at future timelike infinity from the perspective of the dS/CFT correspondence. We investigate the motion…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Yukinori Iwashita , Hirotaka Yoshino , Tetsuya Shiromizu

We consider the motion of test particles and light rays in a static cylindrically symmetric conformal spacetime given by Said et al [1]. We derive the equations of motion and present their analytical solutions in terms of the Weierstrass…

General Relativity and Quantum Cosmology · Physics 2016-08-16 Bahareh Hoseini , Reza Saffari , Saheb Soroushfar , Jutta Kunz , Saskia Grunau

Let us imagine that there is an overall quantum theory (not necessarily recognized yet) of matter and energy ({\it i.e.}, of elementary fermions and bosons) interacting with the physical spacetime (treated on a quantum level). Since states…

High Energy Physics - Theory · Physics 2007-05-23 Wojciech Krolikowski

The Friedmann cosmological solution of the standard Einstein gravitational field equation has a curvature singularity at a moment in time known as the Big Bang. It has been suggested that this Big Bang curvature singularity can be…

General Relativity and Quantum Cosmology · Physics 2026-04-09 Frans R. Klinkhamer

Consistency relations involving the soft limit of the (n + 1)-correlator functions of dark matter and galaxy overdensities can be obtained, both in real and redshift space, thanks to the symmetries enjoyed by the Newtonian equations of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Alexandros Kehagias , Jorge Noreña , Hideki Perrier , Antonio Riotto

We construct a large class of vacuum solutions of the Einstein equations without any symmetries and with controlled asymptotics near a timelike singularity. The solutions are obtained by a Fuchs analysis of the equations which evolve the…

General Relativity and Quantum Cosmology · Physics 2016-05-12 Paul Klinger

A simple yet systematic new algorithm to investigate the global structure of Kerr-Newman spacetime is suggested. Namely, the global structure of \theta=const. timelike submanifolds of Kerr-Newman metric are studied by introducing a new time…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Hongsu Kim