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Related papers: Fractional Einstein-Hilbert Action Cosmology

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We analyze the functional integral for quantum Conformal Gravity and show that with the help of a Hubbard-Stratonovich transformation, the action can be broken into a local quadratic-curvature theory coupled to a scalar field. A one-loop…

High Energy Physics - Theory · Physics 2015-06-08 Petr Jizba , Hagen Kleinert , Fabio Scardigli

Fractional kinetic theory plays a vital role in describing anomalous diffusion in terms of complex dynamics generating semi-Markovian processes. Recently, the variational principle and associated Levy Ansatz have been proposed in order to…

Disordered Systems and Neural Networks · Physics 2018-10-15 Sumiyoshi Abe

We introduce a dynamical model to reduce a large cosmological constant to a sufficiently small value. The basic ingredient in this model is a distinction which has been made between the two unit systems used in cosmology and particle…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Yousef Bisabr

We construct the covariant nonlocal action for recently suggested long-distance modifications of gravity theory motivated by the cosmological constant and cosmological acceleration problems. This construction is based on the special…

High Energy Physics - Theory · Physics 2007-05-23 A. O. Barvinsky

The challenging issue of determining the correct $f(R)$ among several possibilities is here revised by means of numerical reconstructions of the modified Friedmann equations around the redshift interval $z\in[0,1]$. Frequently, a severe…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-24 Liberato Pizza

We present an alternative nonconservative gravitational theory based on the Herglotz variational principle in a fully covariant form. The present model may be seen as an improvement of the theory proposed in Ref. [Lazo et al, Phys. Rev. D…

General Relativity and Quantum Cosmology · Physics 2022-06-22 Juilson A. P. Paiva , Matheus J. Lazo , Vilson T. Zanchin

We study a Newtonian cosmological model in the context of a noncommutative space. It is shown that the trajectories of a test particle undergo modifications such that it no longer satisfies the cosmological principle. For the case of a…

High Energy Physics - Theory · Physics 2010-11-05 Juan M. Romero , J. A. Santiago

We consider the cosmological application of a (variant of) relatively newly proposed model \cite{1609.06915} unifying inflation, dark energy, dark matter, and the Higgs mechanism. The model was originally defined using additional…

General Relativity and Quantum Cosmology · Physics 2019-06-21 Denitsa Staicova , Michail Stoilov

We present an alternative cosmology based on conformal gravity, as originally introduced by H. Weyl and recently revisited by P. Mannheim and D. Kazanas. Unlike past similar attempts our approach is a purely kinematical application of the…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Gabriele U. Varieschi

In this paper, we introduce a new classical fractional particle model incorporating fractional first derivatives. This model represents a natural extension of the standard classical particle with kinetic energy being quadratic in fractional…

General Physics · Physics 2024-07-23 A. V. Crisan , C. M. Porto , C. F. L. Godinho , I. V. Vancea

We develop a novel framework for describing quantum fluctuations in field theory, with a focus on cosmological applications. Our method uniquely circumvents the use of operator/Hilbert-space formalism, instead relying on a systematic…

General Relativity and Quantum Cosmology · Physics 2024-06-25 Ding Ding , Zhao Yu , Yidun Wan

Fractional calculus is an effective tool in incorporating the effects of non-locality and memory into physical models. In this regard, successful applications exist rang- ing from signal processing to anomalous diffusion and quantum…

General Physics · Physics 2014-08-26 S. S. Bayin , J. P. Krisch

We consider cosmological models based on the spectral action formulation of (modified) gravity. We analyze the coupled effects, in this model, of the presence of nontrivial cosmic topology and of fractality in the large scale structure of…

General Relativity and Quantum Cosmology · Physics 2022-08-31 Pedro Guicardi , Matilde Marcolli

The covariant canonical transformation theory applied to the relativistic Hamiltonian theory of classical matter fields in dynamical space-time yields a novel (first order) gauge field theory of gravitation. The emerging field equations…

General Relativity and Quantum Cosmology · Physics 2023-11-29 David Vasak , Johannes Kirsch , Dirk Kehm , Juergen Struckmeier

In this paper we introduce the fractional dark energy model, in which the accelerated expansion of the Universe is driven by a nonrelativistic gas (composed by either fermions or bosons) with a noncanonical kinetic term. The kinetic energy…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-20 Ricardo G. Landim

In the era of precision cosmology, different observational data has led to precise measurements of the Hubble constant that differ significantly, what has been called the Hubble tension problem. In order to solve such a discrepancy, many…

General Relativity and Quantum Cosmology · Physics 2023-04-18 Shin'ichi Nojiri , Sergei D. Odintsov , Diego Sáez-Chillón Gómez

In this paper, the dynamical behavior of the accelerated expansion of the universe is discussed within the framework of $f(T)$ gravity, considering power law functional form of $ f(T)=\alpha (-T)^{n}$. Two distinct redshift-dependent…

General Relativity and Quantum Cosmology · Physics 2025-08-29 Shivank Pal , Romanshu Garg , Gyan Prakash Singh , Gauree Shanker

We propose a modified gravity theory by extending the Einstein-Hilbert action with an arbitrary function of the Ricci scalar and the Kretschmann scalar invariants. The resulting modified Friedmann equations for a spatially flat FRW universe…

General Relativity and Quantum Cosmology · Physics 2026-05-29 A. Dehyadegari , A. Sheykhi

A new type of fluid matter model in general relativity is introduced, in which the fluid particles are subject to velocity diffusion without friction. In order to compensate for the energy gained by the fluid particles due to diffusion, a…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Simone Calogero

We survay our recent results on fractional gravity theory. It is also provided the Main Theorem on encoding of geometric data (metrics and connections in gravity and geometric mechanics) into solitonic hierarchies. Our approach is based on…

Mathematical Physics · Physics 2012-03-13 Dumitru Baleanu , Sergiu I. Vacaru
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