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The cosmological implications of the Covariant Canonical Gauge Theory of Gravity (CCGG) are investigated. We deduce that, in a metric compatible geometry, the requirement of covariant conservation of matter invokes torsion of space-time. In…

General Relativity and Quantum Cosmology · Physics 2024-10-28 David Vasak , Johannes Kirsch , Juergen Struckmeier

Extending previous results [Phys. Rev.D {\bf 56}, 6351 (1997)], we estimate the back reaction of cosmological gravitons in the expansion dynamics, during the matter age. Tensor perturbations with scales larger than the Hubble radius are…

Astrophysics · Physics 2009-10-31 M. R. de Garcia Maia , J. C. Carvalho , J. S. Alcaniz

The dark energy-cold dark matter paradigm ($\Lambda$CDM) has gained widespread acceptance because it explains the pattern of anisotropies observed in the cosmic microwave background radiation, the observed distribution of large scale…

Astrophysics of Galaxies · Physics 2019-12-03 Robert H. Sanders

The discrepancy between dynamical mass measures of objects such as galaxies and the observed distribution of luminous matter in the universe is typically explained by invoking an unseen ``dark matter'' component. Dark matter must…

Astrophysics · Physics 2015-06-24 William H. Kinney , Martina Brisudova

We show that dark energy and dark matter can be described simultaneously by ordinary Einstein gravity interacting with a single scalar field provided the scalar field Lagrangian couples in a symmetric fashion to two different spacetime…

General Relativity and Quantum Cosmology · Physics 2016-11-29 Eduardo Guendelman , Emil Nissimov , Svetlana Pacheva

Einstein-Cartan theory is an extension of the standard formulation of General Relativity where torsion (the antisymmetric part of the affine connection) is non-vanishing. Just as the space-time metric is sourced by the stress-energy tensor…

General Relativity and Quantum Cosmology · Physics 2019-12-30 Francisco Cabral , Francisco S. N. Lobo , Diego Rubiera-Garcia

The similar cosmological abundances observed for visible and dark matter suggest a common origin for both. By viewing the dark matter density as a dark-sector asymmetry, mirroring the situation in the visible sector, we show that the…

High Energy Physics - Phenomenology · Physics 2012-03-01 Kalliopi Petraki , Mark Trodden , Raymond R. Volkas

More than sixty years ago Zwicky made the case that the great clusters of galaxies are held together by the gravitational force of unseen (dark) matter. Today, the case is stronger and more precise: Dark, nonbaryonic matter accounts for 30%…

Astrophysics · Physics 2016-11-23 Michael S. Turner

Beginning with a geometric motivation for dark matter going back to the axioms of general relativity, we show how scalar field dark matter, which naturally forms dark matter density waves due to its wave nature, may cause the observed…

General Physics · Physics 2012-12-27 Hubert L. Bray

The explicit violation of the general gauge invariance/relativity is adopted as the origin of dark matter and dark energy of the gravitational nature. The violation of the local scale invariance alone, with the residual unimodular one, is…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Yu. F. Pirogov

We generalize Einstein's General Relativity (GR) by assuming that all matter (including macro-objects) has quantum effects. An appropriate theory to fulfill this task is Gauge Theory Gravity (GTG) developed by the Cambridge group. GTG is a…

General Relativity and Quantum Cosmology · Physics 2022-12-14 Da-Ming Chen

Universe heating in $R^2$-modified gravity is considered. The rates of particle production by the scalaron are calculated for different decay channels. Freezing of massive stable relics with the interaction strength typical for…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-15 E. V. Arbuzova , A. D. Dolgov

We show that in cosmology the gravitational action of the far away matter has quite relevant effects, if retardation of the forces and discreteness of matter (with its spatial correlation) are taken into account. The expansion rate is found…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-03 A. Carati , S. L. Cacciatori , L. Galgani

We study the phenomenological consequences of the recently proposed idea of a running gravitational coupling on macroscopic scales. When applied to the rotation curves of galaxies, we find that their flatness requires the presence of…

Astrophysics · Physics 2010-11-01 Orfeu Bertolami , Juan Garcia-Bellido

Neutrino masses may arise from spontaneous breaking of ungauged lepton number. Due to quantum gravity effects the associated Goldstone boson - the majoron - will pick up a mass. We determine the lifetime and mass required by cosmic…

Astrophysics · Physics 2008-12-18 M. Lattanzi , J. W. F. Valle

The effective evolution of an inhomogeneous universe model in Einstein's theory of gravitation may be described in terms of spatially averaged scalar variables. This evolution can be modeled by solutions of a set of Friedmann equations for…

General Relativity and Quantum Cosmology · Physics 2011-02-25 Thomas Buchert

In the context of the fact that the existence of dark energy causing the accelerated expansion of the universe has been confirmed by the WMAP and the Sloan Digital Sky Survey, we re-examine gravitation itself, starting with the formulation…

General Physics · Physics 2007-05-23 B. G. Sidharth

We revise the cosmological standard model presuming that matter, i.e. baryons and cold dark matter, exhibits a non-vanishing pressure mimicking the cosmological constant effects. In particular, we propose a scalar field Lagrangian $\mathcal…

General Relativity and Quantum Cosmology · Physics 2018-11-28 Orlando Luongo , Marco Muccino

We study the cosmological evolution of an induced gravity model with a self-interacting scalar field $\sigma$ and in the presence of matter and radiation. Such model leads to Einstein Gravity plus a cosmological constant as a stable…

Astrophysics · Physics 2008-11-26 F. Finelli , A. Tronconi , G. Venturi

The stress-energy tensor of the quantum vacuum is studied for the particular case of quantum electrodynamics (QED), that is a fictituous universe where only the electromagnetic and the electron-positron fields exist. The integrals involved…

General Relativity and Quantum Cosmology · Physics 2015-05-12 Emilio Santos
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