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We propose that at the beginning of the universe gravity existed in a limbo either because it was switched off or because it was only conformally coupled to all particles. This picture can be reverse-engineered from the requirement that the…

General Relativity and Quantum Cosmology · Physics 2015-12-09 Giovanni Amelino-Camelia , Michele Arzano , Giulia Gubitosi , Joao Magueijo

Gauge theories of conformal spacetime symmetries are presented which merge features of Yang-Mills theory and general relativity in a new way. The models are local but nonpolynomial in the gauge fields, with a nonpolynomial structure that…

High Energy Physics - Theory · Physics 2014-11-18 Friedemann Brandt

We explore the possibility of a consistent cosmology based on the gauge-fixing independent running of the gravitational and cosmological constants ($G$ and $\Lambda$) in the framework of effective quantum gravity. In particular, their…

General Relativity and Quantum Cosmology · Physics 2024-04-30 Nicolas R. Bertini , Davi C. Rodrigues , Ilya L. Shapiro

A generic prediction of the standard cosmology, based on general relativity (GR), dark matter and the cosmological constant (and more generally, smooth dark energy), is that, the two gravitational potentials describing the spatial and…

Astrophysics · Physics 2008-09-18 Pengjie Zhang , Rachel Bean , Michele Liguori , Scott Dodelson

The "Universality Theorem" for gravity shows that f(R) theories (in their metric-affine formulation) in vacuum are dynamically equivalent to vacuum Einstein equations with suitable cosmological constants. This holds true for a generic (i.e.…

General Relativity and Quantum Cosmology · Physics 2014-11-20 L. Fatibene , M. Ferraris , M. Francaviglia

In the present article, which is the first part of a work in three parts, we build an equation of quantum gravity. This equation is tensorial, is equivalent to general relativity in vacuum, but differs completely from general relativity…

General Physics · Physics 2007-11-25 Christophe Real

We find that the total entropy of the massive conformal gravity universe is an increasing function of time, and therefore the cosmological model of the theory passes the generalized second law of thermodynamics test.

General Physics · Physics 2025-05-26 F. F. Faria

General relativity can be formally derived as a flat spacetime theory, but the consistency of the resulting curved metric's light cone with the flat metric's null cone has not been adequately considered. If the two are inconsistent, then…

General Relativity and Quantum Cosmology · Physics 2016-08-31 J. Brian Pitts , W. C. Schieve

A new canonical transformation is found that enables the direct canonical treatment of the conformal factor in general relativity. The resulting formulation significantly simplifies the previously presented conformal geometrodynamics. It…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Charles H. -T. Wang

The absence of an identified consequence at solar system scale of the cosmological space expansion is usually explained considering that space expansion does not affect local anysotropies in matter distribution. This can also be explained…

General Physics · Physics 2007-05-23 A. Gouveia Oliveira , Rodrigo de Abreu

We investigate the impact of conformal transformations on the physical properties of solution trajectories in nonmetricity gravity. Specifically, we explore the phase-space and reconstruct the cosmological history of a spatially flat…

General Relativity and Quantum Cosmology · Physics 2023-12-19 Nikolaos Dimakis , Kevin Duffy , Alex Giacomini , Alexander Yu. Kamenshchik , Genly Leon , Andronikos Paliathanasis

The simplest variant of gauge gravitation theory in Riemann-Cartan spacetime leading to the solution of the problem of cosmological singularity and dark energy problem is investigated. It is shown that this theory by certain restrictions on…

General Relativity and Quantum Cosmology · Physics 2017-12-06 A. V. Minkevich

We investigate vacuum solutions of Einstein's equation for a universe with an S^1 topology of time. Such a universe behaves like a time-machine and has geodesics which coincide with closed time-like curves (CTCs). A system evolving along a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Moninder Singh Modgil , Deshdeep Sahdev

The Maxwell extension of the conformal algebra is presented. With the help of gauging the Maxwell-conformal group, a conformally invariant theory of gravity is constructed. In contrast to the conventional conformally invariant actions, our…

High Energy Physics - Theory · Physics 2020-02-21 Salih Kibaroğlu , Oktay Cebecioğlu

We present a classical theory of gravity, which is singularity free at short distances and reduces to General Relativity at large distances. We discuss its implications.

General Relativity and Quantum Cosmology · Physics 2025-02-19 Saurya Das , Mitja Fridman , Sourav Sur

We first review the cosmological constant problem, and then mention a conjecture of Feynman according to which the general relativistic theory of gravity should be reformulated in such a way that energy does not couple to gravity. We point…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Murat Özer

The postulate of universal Weyl conformal symmetry for all elementary physical fields introduces nonclassical gravitational effects in both conformal gravitation(CG) and the conformal Higgs model (CHM). The resulting theory is found to…

General Relativity and Quantum Cosmology · Physics 2023-12-27 R. K. Nesbet

A physical theory of the world is presented under the unifying principle that all of nature is laid out before us and experienced through the passage of time. The one-dimensional progression in time is opened out into a multi-dimensional…

General Physics · Physics 2016-07-01 David J. Jackson

The objective of this thesis is to present a viable extension of general relativity free from cosmological singularities. A viable cosmology, in this sense, is one that is free from ghosts, tachyons or exotic matter, while staying true to…

General Relativity and Quantum Cosmology · Physics 2017-04-25 Aindriú Conroy

In quantum cosmology, one applies quantum physics to the whole universe. While no unique version and no completely well-defined theory is available yet, the framework gives rise to interesting conceptual, mathematical and physical…

General Relativity and Quantum Cosmology · Physics 2015-01-21 Martin Bojowald