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Related papers: Seminal Electromagnetic fields from preinflation

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We investigate the circumstances under which cosmic inflation can arise from very inhomogeneous initial conditions using numerical relativity simulations. Previous studies have not considered cases with non-zero momentum density due to…

General Relativity and Quantum Cosmology · Physics 2023-12-15 Maxence Corman , William E. East

The physics of the inflationary universe requires the study of the out of equilibrium evolution of quantum fields in curved spacetime. We present the evolution for both the geometry and the matter (described by the quantum inflaton field)…

Astrophysics · Physics 2007-05-23 D. Boyanovsky , D. Cormier , H. J. de Vega , R. Holman , S. P. Kumar

There is sufficient amount of internal evidence in the nature of gravitational theories to indicate that gravity is an emergent phenomenon like, e.g, elasticity. Such an emergent nature is most apparent in the structure of gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 T. Padmanabhan

We propose a simple modified gravity model without any initial matter fields in terms of several alternative non-Riemannian spacetime volume elements within the metric (second order) formalism. We show how the non-Riemannian…

General Relativity and Quantum Cosmology · Physics 2019-10-02 David Benisty , Eduardo Guendelman , Emil Nissimov , Svetlana Pacheva

Quantum geometry predicts that a universe evolves through an inflationary phase at small volume before exiting gracefully into a standard Friedmann phase. This does not require the introduction of additional matter fields with ad hoc…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald

Process of formation of the universe with its further expansion in the first evolution stage is investigated in the framework of Friedmann-Robertson-Walker metrics on the basis of quantum model, where a new type of matter is introduced,…

General Relativity and Quantum Cosmology · Physics 2013-01-17 Sergei P. Maydanyuk

The possible cosmological effects of primordial fluctuation corrections to the evolution equation of matter obtained from the Wheeler--De Witt equation are explored. In particular, both the metric and a scalar matter field are expanded…

General Relativity and Quantum Cosmology · Physics 2008-11-26 C. Bertoni , E. Carretti , F. Finelli , A. Messina , G. Venturi

The mechanism for triggering the universe inflation could be that at very early periods the time variable was discrete instead of smooth. Alternatively, and perhaps equivalently, it could be the consequence that the metrics of the early…

High Energy Physics - Theory · Physics 2016-12-28 Laurent Baulieu

In this paper, we study the model of the late universe with the homogeneous, isotropic and flat Friedmann-Robertson-Walker metric, where the source of the gravitational field is based on the fermion and boson field, with the Maxwell term…

General Relativity and Quantum Cosmology · Physics 2020-07-13 O. Razina , P. Tsyba , B. Meirbekov , R. Myrzakulov

Quantum field theory, which is generally used to describe the origin of large-scale gravitational perturbations during cosmic inflation, has been shown to omit an important physical effect in curved space-time, the nonlocal entanglement…

General Relativity and Quantum Cosmology · Physics 2022-04-01 Craig Hogan

This thesis is dedicated to analysing the generation and destruction of quantum correlations in the context of inflationary cosmology and an experiment of 'analogue' preheating. Inflation is a phase of accelerated expansion of the Universe,…

General Relativity and Quantum Cosmology · Physics 2024-12-04 Amaury Micheli

The early universe provides an opportunity for quantum gravity to connect to observation by explaining the large-scale structure of the Universe. In the group field theory (GFT) approach, a macroscopic universe is described as a GFT…

General Relativity and Quantum Cosmology · Physics 2018-12-05 Steffen Gielen , Daniele Oriti

The origin of magnetic fields observed on both astrophysical and cosmological scales is a compelling problem that has the potential to shed light on the early Universe. We analytically investigate inflationary magnetogenesis in scenarios…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-08 Bill Atkins , Debika Chowdhury , Alisha Marriott-Best , Gianmassimo Tasinato

Primordial magnetic fields may account for all or part of the fields observed in galaxies. We consider the evolution of the magnetic fields created by pseudoscalar effects in the early universe. Such processes can create force-free fields…

Astrophysics · Physics 2009-10-31 George B. Field , Sean M. Carroll

We investigate cosmological predictions on the early universe based on the noncommutative geometry models of gravity coupled to matter. Using the renormalization group analysis for the Standard Model with right handed neutrinos and Majorana…

High Energy Physics - Theory · Physics 2009-08-27 Matilde Marcolli , Elena Pierpaoli

In standard inflationary cosmology, scalar and tensor perturbations grew as the Universe expanded and froze when their wavelengths exceeded the Hubble horizon, producing a tell-tale signature in the fluctuation spectrum and amplitude of the…

General Relativity and Quantum Cosmology · Physics 2023-07-21 Fulvio Melia

In the context of Quantum Cosmology and the Wheeler-DeWitt equation we investigate the possible effects of a non semiclassical wave-function of the universe on the evolution of the inflationary perturbations. These are associated with the…

General Relativity and Quantum Cosmology · Physics 2018-06-20 A. Y. Kamenshchik , A. Tronconi , T. Vardanyan , G. Venturi

We explore the ways in which primordial magnetic fields influence the thermal and ionization history of the post-recombination universe. After recombination the universe becomes mostly neutral resulting also in a sharp drop in the radiative…

Astrophysics · Physics 2008-11-26 Shiv K. Sethi , Kandaswamy Subramanian

It has been recently proposed that the presence of a temporal electromagnetic field on cosmological scales could explain the phase of accelerated expansion that the universe is currently undergoing. The field contributes as a cosmological…

General Physics · Physics 2009-11-13 Jose Beltran Jimenez , Tomi S. Koivisto , Antonio L. Maroto , David F. Mota

As soon as the geometry expands quasi-exponentially the plasma sources are customarily tuned to zero as if the duration of the inflationary phase was immaterial for the gauge field fluctuations at large-scale. The serendipitous…

High Energy Physics - Theory · Physics 2015-06-05 Massimo Giovannini
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