Results 31 to 40 of about 2,700,632 (80)
Covariant action for bouncing cosmologies in modified Gauss-Bonnet gravity
, 2019 Cyclic universes with bouncing solutions are candidates for solving the big bang initial singularity problem. Here we seek bouncing solutions in a modified Gauss-Bonnet gravity theory, of the type $R+f(G)$, where $R$ is the Ricci scalar, $G$ is the Gauss-
Lemos, José P. S. +2 more
core +1 more source
The Geometry of Black Hole singularities [PDF]
, 2014 Recent results show that important singularities in General Relativity can be naturally described in terms of finite and invariant canonical geometric objects. Consequently, one can write field equations which are equivalent to Einstein's at non-singular
Stoica, Ovidiu Cristinel
core +3 more sources
Switching internal times and a new perspective on the 'wave function of the universe'
, 2019 Despite its importance in general relativity, a quantum notion of general covariance has not yet been established in quantum gravity and cosmology, where, given the a priori absence of coordinates, it is necessary to replace classical frames with ...
Hoehn, Philipp A
core +1 more source
Cyclic Cosmology and Holographic Entanglement Entropy [PDF]
, 2018 No abstract prepared.
arxiv +1 more source
Loop Quantum Gravity: Four Recent Advances and a Dozen Frequently Asked Questions
, 2007 As per organizers' request, my talk at the 11th Marcel Grossmann Conference consisted of two parts. In the first, I illustrated recent advances in loop quantum gravity through examples.
Ashtekar, Abhay
core +1 more source
The volume operator in covariant quantum gravity [PDF]
, 2010 A covariant spin-foam formulation of quantum gravity has been recently developed, characterized by a kinematics which appears to match well the one of canonical loop quantum gravity.
Alexandrov S +30 more
core +3 more sources
(Loop) quantum gravity and the inflationary scenario [PDF]
, 2015 Quantum gravity, as a fundamental theory of space-time, is expected to reveal how the universe may have started, perhaps during or before an inflationary epoch.
Bojowald, Martin
core +2 more sources
On the Chern-Simons State in General Relativity and Modified Gravity Theories
, 2014 The Chern-Simons state is one solution to quantum constraints of gravity in the context of general relativity (GR) theory if we use Ashtekar's variables and if one orders the constraints with the triads to the left.
R. Rosas-Rodríguez
semanticscholar +1 more source
Singularities and Quantum Gravity
, 2007 Although there is general agreement that a removal of classical gravitational singularities is not only a crucial conceptual test of any approach to quantum gravity but also a prerequisite for any fundamental theory, the precise criteria for non-singular
Bojowald, Martin
core +2 more sources
Loop quantum gravity corrections to gravitational wave dispersion [PDF]
, 1997 Cosmological tensor perturbations equations are derived for Hamiltonian cosmology based on Ashtekar's formulation of general relativity, including typical quantum gravity effects in the Hamiltonian constraint as they are expected from loop quantum ...
Bojowald, Martin, Hossain, Golam Mortuza
core +3 more sources