scholarly journals Quantum-gravity effects for excited states of inflationary perturbations

2019 ◽  
Vol 99 (10) ◽  
Author(s):  
David Brizuela ◽  
Claus Kiefer ◽  
Manuel Krämer ◽  
Salvador Robles-Pérez
Keyword(s):  
Quantum Gravity ◽  
Excited States ◽  
Gravity Effects

scholarly journals LARGE QUANTUM GRAVITY EFFECTS: CYLINDRICAL WAVES IN FOUR DIMENSIONS

2000 ◽  
Vol 09 (06) ◽  
pp. 669-686 ◽  
Author(s):  
MARÍA E. ANGULO ◽  
GUILLERMO A. MENA MARUGÁN
Keyword(s):  
Quantum Gravity ◽  
Symmetry Axis ◽  
Point Of View ◽  
Three Dimensions ◽  
Asymptotic Region ◽  
Four Dimensions ◽  
Cylindrical Waves ◽  
Significant Difference ◽  
Gravity Effects ◽  
Linearly Polarized

Linearly polarized cylindrical waves in four-dimensional vacuum gravity are mathematically equivalent to rotationally symmetric gravity coupled to a Maxwell (or Klein–Gordon) field in three dimensions. The quantization of this latter system was performed by Ashtekar and Pierri in a recent work. Employing that quantization, we obtain here a complete quantum theory which describes the four-dimensional geometry of the Einstein–Rosen waves. In particular, we construct regularized operators to represent the metric. It is shown that the results achieved by Ashtekar about the existence of important quantum gravity effects in the Einstein–Maxwell system at large distances from the symmetry axis continue to be valid from a four-dimensional point of view. The only significant difference is that, in order to admit an approximate classical description in the asymptotic region, states that are coherent in the Maxwell field need not contain a large number of photons anymore. We also analyze the metric fluctuations on the symmetry axis and argue that they are generally relevant for all of the coherent states.

scholarly journals Quantum Gravity Phenomenology from the Thermodynamics of Spacetime

Universe ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 50
Author(s):  
Ana Alonso-Serrano ◽  
Marek Liška
Keyword(s):  
Quantum Gravity ◽  
Big Bang ◽  
Einstein Equations ◽  
Logarithmic Term ◽  
Quantum Gravity Phenomenology ◽  
Gravity Effects ◽  
Energy Quantum ◽  
The Big Bang ◽  
Big Bang Singularity ◽  
Modified Dynamics

This work is based on the formalism developed in the study of the thermodynamics of spacetime used to derive Einstein equations from the proportionality of entropy within an area. When low-energy quantum gravity effects are considered, an extra logarithmic term in the area is added to the entropy expression. Here, we present the derivation of the quantum modified gravitational dynamics from this modified entropy expression and discuss its main features. Furthermore, we outline the application of the modified dynamics to cosmology, suggesting the replacement of the Big Bang singularity with a regular bounce.

scholarly journals Do we Observe Quantum Gravity Effects at Galactic Scales?

2006 ◽  
Vol 20 ◽  
pp. 251-256
Author(s):  
M. Reuter ◽  
H. Weyer
Keyword(s):  
Quantum Gravity ◽  
Gravity Effects

scholarly journals A PROPOSAL TO RESOLVE THE BLACK HOLE INFORMATION PARADOX

2002 ◽  
Vol 11 (10) ◽  
pp. 1537-1540 ◽  
Author(s):  
SAMIR D. MATHUR
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
String Theory ◽  
Quantum Gravity ◽  
Bound State ◽  
Nonlocal Effects ◽  
Information Paradox ◽  
Microscopic Scale ◽  
Gravity Effects ◽  
Black Hole Information

The entropy and information puzzles arising from black holes cannot be resolved if quantum gravity effects remain confined to a microscopic scale. We use concrete computations in nonperturbative string theory to argue for three kinds of nonlocal effects that operate over macroscopic distances. These effects arise when we make a bound state of a large number of branes, and occur at the correct scale to resolve the paradoxes associated with black holes.

scholarly journals Quantum Gravity Effects in Statistical Mechanics with Modified Dispersion Relation

2018 ◽  
Vol 2018 ◽  
pp. 1-7
Author(s):  
Shovon Biswas ◽  
Mir Mehedi Faruk
Keyword(s):  
Dispersion Relation ◽  
Quantum Gravity ◽  
Statistical Mechanics ◽  
Planck Scale ◽  
Maximum Energy ◽  
Gravity Models ◽  
Momentum Scale ◽  
Modified Dispersion Relation ◽  
Gravity Effects ◽  
Photon Gas

Planck scale inspired theories which are also often accompanied with maximum energy and/or momentum scale predict deformed dispersion relations compared to ordinary special relativity and quantum mechanics. In this paper, we resort to the methods of statistical mechanics in order to determine the effects of a deformed dispersion relation along with an upper bound in the partition function that maximum energy and/or momentum scale can have on the thermodynamics of photon gas. We also analyzed two distinct quantum gravity models in this paper.

Quantum gravity effects on scalar particle tunneling from rotating BTZ black hole

2018 ◽  
Vol 33 (12) ◽  
pp. 1850070 ◽  
Author(s):  
I. Ablu Meitei ◽  
T. Ibungochouba Singh ◽  
S. Gayatri Devi ◽  
N. Premeshwari Devi ◽  
K. Yugindro Singh
Keyword(s):  
Black Hole ◽  
Quantum Gravity ◽  
Generalized Uncertainty Principle ◽  
Scalar Particle ◽  
Mass Energy ◽  
Btz Black Hole ◽  
Logarithmic Term ◽  
Scalar Particles ◽  
Gravity Effects ◽  
Correction Terms

Tunneling of scalar particles across the event horizon of rotating BTZ black hole is investigated using the Generalized Uncertainty Principle to study the corrected Hawking temperature and entropy in the presence of quantum gravity effects. We have determined explicitly the various correction terms in the entropy of rotating BTZ black hole including the logarithmic term of the Bekenstein–Hawking entropy [Formula: see text], the inverse term of [Formula: see text] and terms with inverse powers of [Formula: see text], in terms of properties of the black hole and the emitted particles — mass, energy and angular momentum. In the presence of quantum gravity effects, for the emission of scalar particles, the Hawking radiation and thermodynamics of rotating BTZ black hole are observed to be related to the metric element, hence to the curvature of space–time.

scholarly journals Quantum gravity effects on Hořava–Lifshitz black hole

2018 ◽  
Vol 928 ◽  
pp. 415-434 ◽  
Author(s):  
B. Pourhassan ◽  
S. Upadhyay ◽  
H. Saadat ◽  
H. Farahani
Keyword(s):  
Black Hole ◽  
Quantum Gravity ◽  
Gravity Effects ◽  
Lifshitz Black Hole
Sign in / Sign up

Export Citation Format

Share Document