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Related papers: Cosmic acceleration in Lovelock quantum gravity

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This paper discusses the problem of inflation in the context of Friedmann-Robertson-Walker Cosmology. We show how, after a simple change of variables, one can quantize the problem in a way which parallels the classical discussion. The…

High Energy Physics - Theory · Physics 2007-05-23 Marvin Weinstein , Ratin Akhoury

We present a cosmological model arising from a gravitational theory with an infinite tower of higher-order curvature invariants that can reproduce the entire evolution of the Universe: from inflation to late-time acceleration, without…

General Relativity and Quantum Cosmology · Physics 2022-02-10 Luisa G. Jaime , Gustavo Arciniega

An alternative to dark energy as an explanation for the present phase of accelerated expansion of the Universe is that the Friedmann equation is modified, e.g. by extra dimensional gravity, on large scales. We explore a natural…

Astrophysics · Physics 2009-11-10 Oystein Elgaroy , Tuomas Multamaki

We investigate the dynamics of super-inflation in two versions of Loop Quantum Cosmology, one in which the Friedmann equation is modified by the presence of inverse volume corrections, and one in which quadratic corrections are important.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 E. J. Copeland , D. J. Mulryne , N. J. Nunes , M. Shaeri

We propose the unified description of the early acceleration (cosmological inflation) and the present epoch of so called "dark energy". The inflation can be described by cosmic fluid with van der Waals equation of state and with viscosity…

General Relativity and Quantum Cosmology · Physics 2022-01-19 A. V. Astashenok , S. D. Odintsov , A. S. Tepliakov

Models of cosmic inflation posit an early phase of accelerated expansion of the universe, driven by the dynamics of one or more scalar fields in curved spacetime. Though detailed assumptions about fields and couplings vary across models,…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-09 Alan H. Guth , David I. Kaiser , Yasunori Nomura

The Universe is currently in a phase of accelerated expansion, a fact that was experimentally proven in the late 1990s. Cosmological models involving scalar fields allow the description of this accelerated expansion regime in the Cosmos and…

General Relativity and Quantum Cosmology · Physics 2023-10-11 Joao R. L. Santos , S. Santos da Costa , Romario S. Santos

The impact of topological terms that modify the Hilbert-Einstein action is here explored by virtue of a further $f(G)$ contribution. In particular, we investigate the phase-space stability and critical points of an equivalent scalar field…

General Relativity and Quantum Cosmology · Physics 2025-05-01 Giannis Papagiannopoulos , Orlando Luongo , Genly Leon , Andronikos Paliathanasis

We construct a model of higher dimensional cosmology in which extra dimensions are frozen by virtue of the cubic-order Lovelock gravity throughout the cosmic history from inflation to the present with radiation and matter-dominated regimes…

General Relativity and Quantum Cosmology · Physics 2020-10-21 Hiroaki W. H. Tahara , Tsutomu Kobayashi , Jun'ichi Yokoyama

A self-consistent pre-inflationary extension of the inflationary scenario with the Starobinsky potential, favored by Planck data, is studied using techniques from loop quantum cosmology (LQC). The results are compared with the quadratic…

General Relativity and Quantum Cosmology · Physics 2016-05-25 Béatrice Bonga , Brajesh Gupt

Using techniques from loop quantum gravity, the standard theory of cosmological perturbations was recently generalized to encompass the Planck era. We now apply this framework to explore pre-inflationary dynamics. The framework enables us…

General Relativity and Quantum Cosmology · Physics 2015-03-12 Ivan Agullo , Abhay Ashtekar , William Nelson

This work examines the cosmological implications of two functional forms of $f(R,T) = R + \alpha T^n$ gravity: for two different value of $n $ where $n=1$ and $n\neq 1$, and $\alpha$ and $n$ are free parameters. The modified Friedmann…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-24 Mustapha Lamaaoune

I consider the generic model independent predictions of the theory of quantum cosmological perturbations. To describe the stage of cosmic inflation, where these perturbations are amplified, the hydrodynamical approch is used. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Viatcheslav Mukhanov

We put forward novel extensions of Starobinsky inflation, involving a class of 'geometric' higher-curvature corrections that yield second-order Friedmann-Lema\^itre equations and second-order-in-time linearized equations around cosmological…

High Energy Physics - Theory · Physics 2021-05-26 Pablo A. Cano , Kwinten Fransen , Thomas Hertog

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

Researches in the several decades have shown that the dynamics of gravity is closely related to thermodynamics of the horizon. In this paper, we derive the Friedmann acceleration equation based on the idea of "emergence of space" and…

General Relativity and Quantum Cosmology · Physics 2018-09-03 Fei-Quan Tu , Yi-Xin Chen , Bin Sun , You-Chang Yang

Cosmology appears as the most promising way to test and constrain quantum gravity theories. Loop quantum gravity is among the most advanced attempts to perform a non-perturbative quantization of general relativity. Its cosmological…

General Relativity and Quantum Cosmology · Physics 2023-06-27 Killian Martineau

Based on an analogy between diffraction integral formalism of classical field propagation and Feynman path integral approach to quantum field theory, we develop a quantum model for light and radiation in Rindler spacetime. The framework…

General Relativity and Quantum Cosmology · Physics 2025-06-04 Fujin Wang , Syed Masood , L. G. Wang

Cosmological solutions for homogeneous isotropic models in the framework of the Poincar\'e gauge theory of gravity based on gravitational Lagrangian adopted in the paper by Kun-Feng Shie, James M. Nester and Hwei-Jang Yo (Phys. Rev. D…

General Relativity and Quantum Cosmology · Physics 2009-08-28 A. V. Minkevich , A. S. Garkun , V. I. Kudin

Padmanabhan [arXiv:1206.4916] argues that the cosmic acceleration can be understood from the perspective that spacetime dynamics is an emergence phenomena. By calculating the difference between the surface degrees of freedom and the bulk…

General Relativity and Quantum Cosmology · Physics 2013-04-19 Ahmad Sheykhi
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