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We show that modelling the universe as a pre-geometric system with emergent quantum modes, and then constructing the classical limit, we obtain a new account of space and gravity that goes beyond Newtonian gravity even in the…

General Physics · Physics 2007-09-20 Reginald T Cahill

Loop quantum cosmology is an application of recent developments for a non-perturbative and background independent quantization of gravity to a cosmological setting. Characteristic properties of the quantization such as discreteness of…

Astrophysics · Physics 2009-11-13 Martin Bojowald

Based on an earlier introduced new class of generalized gravity-matter models defined in terms of two independent non-Riemannian volume forms (alternative generally covariant integration measure densities) on the space-time manifold, we…

High Energy Physics - Theory · Physics 2016-11-29 Eduardo Guendelman , Ramon Herrera , Pedro Labrana , Emil Nissimov , Svetlana Pacheva

We propose that the size of the universe and its rate of expansion cannot be simultaneously specified with arbitrary precision, a quantum mechanical statement encoded in a deformed commutation relation for the scale factor. The deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-15 Savvas M. Koushiappas

Despite all fundamental objections against Newtonian concepts in cosmology, the Friedmann equation derives from these in an astoundingly simple way through application of the shell theorem and conservation of Newtonian energy in an infinite…

General Relativity and Quantum Cosmology · Physics 2017-04-05 Herman Telkamp

This paper proposes a new avenue for understanding the cosmological singularity. The standard cosmological model contains a generic initial singularity usually referred to as the {\em big bang}. Herein, we present a novel idea to extend the…

General Relativity and Quantum Cosmology · Physics 2026-04-15 Justin C. Feng , Shinji Mukohyama , Jean-Philippe Uzan

The Einstein static universe has played a central role in a number of emergent scenarios recently put forward to deal with the singular origin of the standard cosmological model. Here we study the existence and stability of the Einstein…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-01 Saulo Carneiro , Reza Tavakol

A model of an emergent universe is formulated using the mechanism of particle creation. Here the universe is considered as a non-equilibrium thermodynamical system with dissipation due to particle creation mechanism. The universe is chosen…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Subenoy Chakraborty

Plausible cause and effect of the big bang model are presented without violating conventional laws of physics. The initial cosmological singularity is resolved by introducing the uncertainty principle of quantum theory. We postulate that,…

Astrophysics · Physics 2007-05-23 D. C. Choudhury

The effort to discover a quantum theory of gravity is motivated by the need to reconcile the incompatibility between quantum theory and general relativity. Here, we present an alternative approach by constructing a consistent theory of…

High Energy Physics - Theory · Physics 2023-11-28 Jonathan Oppenheim

In this note, it is shown that nonvanishing spatial curvature produces primordial matter in the initially empty universe due to quantum gravity effects. This matter decays faster than radiation and is described by a stiff equation of state.…

General Relativity and Quantum Cosmology · Physics 2026-04-14 V. E. Kuzmichev , V. V. Kuzmichev

I present the theoretical evidence which suggests that gravity is an emergent phenomenon like gas dynamics or elasticity with the gravitational field equations having the same status as, say, the equations of fluid dynamics/elasticity. This…

General Relativity and Quantum Cosmology · Physics 2011-07-13 T. Padmanabhan

The causal set approach to the problem of quantum gravity is based on the hypothesis that spacetime is fundamentally discrete. Spacetime discreteness opens the door to novel types of dynamical law for cosmology and the Classical Sequential…

General Relativity and Quantum Cosmology · Physics 2017-03-23 Fay Dowker , Stav Zalel

The evidence for a Big Bang origin of the Universe is truly compelling, though its cause remains a complete mystery. As the cosmic spacetime is revealed to us with ever improving detail, however, we are beginning to refine the range of its…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-01 Fulvio Melia

Cosmological observations strongly suggest the presence of dark energy which comprises the majority of the current energy density of the universe. The equation of state relating the pressure and energy density of this dark energy, p = w…

Astrophysics · Physics 2007-05-23 Eric Gawiser

Based on some observations, the apparent energy, associated with gravity, of vacuums is defined, with that of normal vacuums to be zero and that of the vacuums losing some energy to be negative. An important application of the energy is its…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Yi-Ping Qin

We explicitly compute the dynamics of closed homogeneous and isotropic universes permeated by a single perfect fluid with a constant equation of state parameter $w$ in the context of a recent reformulation of general relativity, proposed in…

General Relativity and Quantum Cosmology · Physics 2015-05-06 P. P. Avelino

Observations indicate that the universe is effectively flat, but they do not rule out a closed universe. The role of positive curvature is negligible at late times, but can be crucial in the early universe. In particular, positive curvature…

General Relativity and Quantum Cosmology · Physics 2010-04-06 George Ellis , Roy Maartens

The integrals of the Friedmann cosmology equations are identified as constant physical characteristics for both vacuum and non-vacuum cosmic energies. The integrals are found to be numerically coincident. A model shows that the coincidence…

Astrophysics · Physics 2016-08-30 Arthur D. Chernin

We study cosmological solutions for the very early universe beginning at the Planck scale for a universe containing radiation, curvature and, as a simplification of a possible scalar field potential, a cosmological constant term. The…

General Relativity and Quantum Cosmology · Physics 2010-01-30 E. Galindo-Dellavalle , G. German , A. de la Macorra