Results 91 to 100 of about 51,631 (191)

A short introduction to cosmology and its current status

SciPost Physics Lecture Notes
The current cosmological model, known as the $\Lambda$-Cold Dark Matter model (or $\Lambda$CDM for short) is one of the most astonishing accomplishments of contemporary theoretical physics.
Pedro G. Ferreira, Alexander Roskill
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Darkness without dark matter and energy – generalized unimodular gravity

Physics Letters B, 2017
We suggest a Lorentz non-invariant generalization of the unimodular gravity theory, which is classically equivalent to general relativity with a locally inert (devoid of local degrees of freedom) perfect fluid having an equation of state with a constant ...
A.O. Barvinsky, A.Yu. Kamenshchik
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Towards inhomogeneous loop quantum cosmology: triangulating Bianchi IX with perturbations

, 2010
This brief article sums up results obtained in arXiv:0911.2653, which develops a constrained SU(2) lattice gauge theory in the "dipole" approximation.
Marciano, Antonino
core   +1 more source

Brane-World Gravity

Living Reviews in Relativity, 2010
The observable universe could be a 1+3-surface (the “brane”) embedded in a 1+3+d-dimensional spacetime (the “bulk”), with Standard Model particles and fields trapped on the brane while gravity is free to access the bulk.
Roy Maartens, Kazuya Koyama
doaj  

Cosmic Inflation, Quantum Information and the Pioneering Role of John S Bell in Cosmology

Universe, 2019
According to the theory of cosmic inflation, the large scale structures observed in our Universe (galaxies, clusters of galaxies, Cosmic Background Microwave—CMB—anisotropy…) are of quantum mechanical origin. They are nothing but vacuum
Jérôme Martin
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On the Geometric Meaning of General Relativity and the Foundations of Newtonian Cosmology

AppliedMath
The geometric foundations of General Relativity are revisited here, with particular attention to its gauge invariance, as a key to understanding the true nature of spacetime.
Jaume de Haro, Emilio Elizalde
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A strictly local solution to the problem of energy in general relativity

Frontiers in Astronomy and Space Sciences
The problem of energy and its conservation is more than a century old in general relativity (GR) and is considered by many scholars to be, at least, not sufficiently solved.
Werner M. Vieira, Nadja S. Magalhaes
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Energy-Flow Cosmology: A Thermodynamic Bridge Between General Relativity and Quantum Field

This study proposes a thermodynamic framework that unifies General Relativity (GR) and Quantum Field Theory (QFT) through a continuous energy-flow field parameterized by entropy S. The model introduces an entropy-dependent coupling and an emergent light speed, showing that both spacetime geometry and quantum fluctuations arise as limiting cases of the ...
openaire   +1 more source

Power-series dynamics equation of fields based on geometric algebra and high-order covariant-derivative schemes

AIP Advances
Based on previous work, we explore in the context of quantum field theory and cosmology a geometric algebra (GA)-based approach to field dynamics through a multi-derivative power-series equation.
R. W. Haase
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A review of basic results on the Bose–Einstein condensate dark matter model

Frontiers in Astronomy and Space Sciences
We review basic results on the Bose–Einstein condensate dark matter (BECDM) model. Self-gravitating BECs experience a collisionless process of gravitational cooling and violent relaxation, leading to BECDM halos with a “core-envelope” structure.
Pierre-Henri Chavanis, Pierre-Henri Chavanis   +1 more
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