中文
相关论文

相关论文: Cosmological particle creation in Weyl geometry

200 篇论文

A Lagrangian relativistic approach to the non--linear dynamics of cosmological perturbations of an irrotational collisionless fluid is considered. Solutions are given at second order in perturbation theory for the relevant fluid and…

天体物理学 · 物理学 2015-06-24 S. Matarrese , O. Pantano , D. Saez

Recently, it has been pointed out that dimensionless actions in four dimensional curved spacetime possess a symmetry which goes beyond scale invariance but is smaller than full Weyl invariance. This symmetry was dubbed {\it restricted Weyl…

高能物理 - 理论 · 物理学 2015-08-26 Ariel Edery , Yu Nakayama

We construct a Weyl-Einsteinian-Cubic Gravity (ECG) as a cubic gauge theory of gravity via abelian gauge and properly tuned compensating real scalar fields. The model is free from any dimensionful parameters. The bare ECG emerges as the…

高能物理 - 理论 · 物理学 2025-09-05 Suat Dengiz

When the full connection of Weyl conformal gravity is varied instead of just the metric, the resulting vacuum field equations reduce to the vacuum Einstein equation, up to the choice of local units, if and only if the torsion vanishes. This…

广义相对论与量子宇宙学 · 物理学 2014-07-30 James T. Wheeler

Using an approximate solution to the $N$-body problem in general relativity, and the \emph{principle of local isotropy at any point}, we construct a cosmological model, with zero curvature, for a universe composed uniquely by collision-less…

广义相对论与量子宇宙学 · 物理学 2014-09-11 Miguel Portilla

A generalized Weyl integrable geometry (GWIG) is obtained from simultaneous affine transformations of the tangent and cotangent bundles of a (pseudo)-Riemannian manifold. In comparison with the classical Weyl integrable geometry (CWIG),…

数学物理 · 物理学 2020-05-26 Fereidoun Sabetghadam

We study Weyl conformal geometry as a general gauge theory of the Weyl group (of Poincar\'e and dilatations symmetries) in a manifestly Weyl gauge covariant formalism in which this geometry is automatically metric and physically relevant.…

高能物理 - 理论 · 物理学 2025-03-31 C. Condeescu , D. M. Ghilencea , A. Micu

We study the theory of Weyl conformal gravity with matter degrees of freedom in a conformally invariant interaction. Specifically, we consider a triplet of scalar fields and SO(3) non-abelian gauge fields, i.e. the Georgi-Glashow model…

高能物理 - 理论 · 物理学 2009-08-07 A. Edery , Luca Fabbri , M. B. Paranjape

We consider Weyl's conformal gravity coupled to a complex matter field in Weyl geometry. It is shown that a Higgs potential naturally arises from a $\tilde R^2$ term in moving from the Jordan frame to the Einstein frame. A massless…

高能物理 - 理论 · 物理学 2021-02-03 Ichiro Oda

We present exact analytical solutions to the Conformal Weyl Gravity cosmological equations that are valid for both the matter and radiation dominated eras. The Primordial Nucleosynthesis process is also exhaustively studied. The main…

天体物理学 · 物理学 2009-10-22 D. Elizondo , G. Yepes

It was recently found that, after performing a Weyl conformal transformation, the familiar analogy between black hole mechanics and black hole thermodynamics becomes ambiguous. It was argued that this fact can be traced back to the…

广义相对论与量子宇宙学 · 物理学 2019-04-16 Fayçal Hammad , Daniel Dijamco

It is shown that the recently geometric formulation of quantum mechanics implies the use of Weyl geometry. It is discussed that the natural framework for both gravity and quantum is Weyl geometry. At the end a Weyl invariant theory is…

广义相对论与量子宇宙学 · 物理学 2007-05-23 Fatimah Shojai , Ali Shojai

Already the simplest examples of Weyl geometry, the static space-time models of general relativity modified by an additional time-homogeneous Weylian length connection lead to beautiful cosmological models (Weyl universes) . The…

天体物理学 · 物理学 2007-05-23 Erhard Scholz

One of the important extensions of Riemann geometry is Weyl geometry, which is essentially based on the ideas of conformal invariance and nonmetricity. A similar non-Riemannian geometry was proposed by Erwin Schr\"{o}dinger in the late…

广义相对论与量子宇宙学 · 物理学 2023-10-10 Lei Ming , Shi-Dong Liang , Hong-Hao Zhang , Tiberiu Harko

In this paper we study the quantum cosmology of homogeneous and isotropic cosmology, via the Weyl-Wigner-Groenewold-Moyal formalism of phase space quantization, with perfect fluid as a matter source. The corresponding quantum cosmology is…

广义相对论与量子宇宙学 · 物理学 2017-01-25 M. Rashki , S. Jalalzadeh

We investigate the warm inflationary scenario in the Weyl geometric gravity theory, in which the action is constructed by adding matter to the simplest conformally invariant gravitational action in Weyl geometry. The $\tilde{R}^2$ theory…

广义相对论与量子宇宙学 · 物理学 2026-05-19 Runhua Huang , Tiberiu Harko , Shi-Dong Liang , Hong-Hao Zhang , Lei Ming

Weyl's conformal theory of gravity is an extension of Einstein's theory of general relativity which associates metrics with 1-forms . In the case of locally integrable (closed non-exact) 1-forms the spacetime manifolds are no more simply…

广义相对论与量子宇宙学 · 物理学 2022-06-09 Michel Duneau

A new method for the construction of conformally invariant equations in an arbitrary four dimensional (pseudo-) Riemannian space is presented. This method uses the Weyl geometry as a tool and exploits the natural conformal invariance we can…

高能物理 - 理论 · 物理学 2015-12-01 Sofiane Faci

The problem of cosmological particle creation for a spatially flat, homogeneous and isotropic Universes is discussed in the context of f(R) theories of gravity. Different from cosmological models based on general relativity theory, it is…

宇宙学与河外天体物理 · 物理学 2011-07-01 S. H. Pereira , C. H. G. Bessa , J. A. S. Lima

We show that there are no new consistent cosmological perfect fluid solutions when in an open neighbourhood ${\cal U}$ of an event the fluid kinematical variables and the electric and magnetic Weyl curvature are all assumed rotationally…

广义相对论与量子宇宙学 · 物理学 2014-11-17 Nazeem Mustapha , George F R Ellis , Henk van Elst , Mattias Marklund