English
Related papers

Related papers: Quantum Matter near a Cosmological Singularity

200 papers

A covariant description of quantum matter fields in the early universe underpins models for the origin of species, e.g. baryogenesis and dark matter production. In nearly all cases the relevant cosmological observables are computed in a…

General Relativity and Quantum Cosmology · Physics 2019-03-11 Mahmoud Parvizi

We show that the quantization ambiguities of loop quantum cosmology, when considered in wider generality, can be used to produce discretionary dynamical behavior. There is an infinite dimensional space of ambiguities which parallels the…

General Relativity and Quantum Cosmology · Physics 2023-05-03 Lautaro Amadei , Alejandro Perez , Salvatore Ribisi

Numerical simulations are performed of a test scalar field in a spacetime undergoing gravitational collapse. The behavior of the scalar field near the singularity is examined and implications for generic singularities are discussed. In…

General Relativity and Quantum Cosmology · Physics 2011-09-12 Ryo Saotome , Ratindranath Akhoury , David Garfinkle

Global existence results in the past time direction of cosmological models with collisionless matter and a massless scalar field are presented. It is shown that the singularity is crushing and that the Kretschmann scalar diverges uniformly…

General Relativity and Quantum Cosmology · Physics 2009-11-11 David Tegankong , Alan D. Rendall

Coupling any interacting quantum mechanical system to gravity in one dimension requires the cosmological constant to belong to the matter energy spectrum and thus to be quantized, even though the gravity sector is free of any quantum…

High Energy Physics - Theory · Physics 2007-05-23 Jan Govaerts

Chaotic BKL dynamics provides a canonical description of the approach to spacelike singularities as a sequence of Kasner epochs grouped into eras. While this paradigm is well established for cosmological singularities, explicit realizations…

High Energy Physics - Theory · Physics 2026-03-09 Elena Cáceres , Ángel J. Murcia , Ayan K. Patra , Juan F. Pedraza

We demonstrate that the Carroll limit of general relativity coupled to matter captures the chaotic mixmaster dynamics of near-singularity limits. Zooming in on the behavior of general relativity close to spacelike singularities reveals rich…

High Energy Physics - Theory · Physics 2025-03-05 Gerben Oling , Juan F. Pedraza

Hardy's theorem states that the hidden variables of any realistic theory of quantum measurement, whose predictions agree with ordinary quantum theory, must have a preferred Lorentz frame. This presents the conflict between special…

Quantum Physics · Physics 2009-10-31 i. c. percival

We hereby show that the Kasner spacetime turns out to be singularity-free in Einstein's conformal gravity in vacuum or in presence of matter. Such a statement is based on the regularity of the curvature invariants and on the geodesic…

General Relativity and Quantum Cosmology · Physics 2019-06-24 Leonardo Modesto , Hui-Yu Zhu , Jun-Yan Zhang

Attempts to formulate a quantum theory of gravitation are collectively known as {\it quantum gravity}. Various approaches to quantum gravity such as string theory and loop quantum gravity, as well as black hole physics and doubly special…

High Energy Physics - Theory · Physics 2011-12-25 Ahmed Farag Ali , Saurya Das , Elias C. Vagenas

Recently, it was shown that the quantum effects of the matter, could be used to determine the conformal degree of freedom of the space-time metric. So both gravity and quantum are geometrical features. Gravity determines the causal…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Fatimah Shojai , Ali Shojai , Mehdi Golshani

An alternative cosmological model is presented, which avoids the requirement of dark energy and dark matter. Based on the proposition that energy conservation should be valid not only locally but also globally, the energy tensor of general…

General Physics · Physics 2007-08-30 Ernst Fischer

We investigate the late-time cosmological behaviour of scalar-tensor theories with a universal multiplicative coupling between the scalar field and the matter Lagrangian in the matter era. This class of theory encompasses the case of the…

General Relativity and Quantum Cosmology · Physics 2014-07-24 Olivier Minazzoli , Aurélien Hees

As shown in the classic work of Belinski, Khalatnikov and Lifshitz, the approach to a generic space-like singularity in general relativity consists of a sequence of eras and epochs in which the metric is locally Kasner, connected by brief…

General Relativity and Quantum Cosmology · Physics 2024-07-22 Pablo Bueno , Pablo A. Cano , Robie A. Hennigar

General relativity predicts a singularity in the beginning of the universe being called big bang. Recent developments in loop quantum cosmology avoid the singularity and the big bang is replaced by a big bounce. A classical theory of…

General Physics · Physics 2011-02-08 Walter Petry

In the last decade, progress on quantization of homogeneous cosmological spacetimes using techniques of loop quantum gravity has led to insights on various fundamental questions and has opened new avenues to explore Planck scale physics.…

General Relativity and Quantum Cosmology · Physics 2016-12-06 Ivan Agullo , Parampreet Singh

We show that the f(T) gravitational paradigm, in which gravity is described by an arbitrary function of the torsion scalar, can provide a mechanism for realizing bouncing cosmologies, thereby avoiding the Big Bang singularity. After…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-07 Yi-Fu Cai , Shih-Hung Chen , James B. Dent , Sourish Dutta , Emmanuel N. Saridakis

We study the interior of black holes in the presence of charged scalar hair of small amplitude $\epsilon$ on the event horizon and show their terminal boundary is a crushing Kasner-like singularity. These spacetimes are spatially…

General Relativity and Quantum Cosmology · Physics 2025-01-09 Warren Li , Maxime Van de Moortel

We argue that massive quantum fields source low-frequency long-wavelength metric fluctuations through the quantum fluctuations of their stress-energy, given reasonable assumptions about the analytic structure of its correlators. This can be…

High Energy Physics - Theory · Physics 2017-03-17 Niayesh Afshordi , Hyungjin Kim , Elliot Nelson

A non-singular bouncing cosmology is generically obtained in loop quantum cosmology due to non-perturbative quantum gravity effects. A similar picture can be achieved in standard general relativity in the presence of a scalar field with a…

General Relativity and Quantum Cosmology · Physics 2014-03-17 Yi-Fu Cai , Edward Wilson-Ewing
‹ Prev 1 4 5 6 7 8 10 Next ›