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We develop a novel model for Cosmological Hyperfluids, that is fluids with intrinsic hypermomentum that induce spacetime torsion and non-metricity. Imposing the Cosmological Principle to Metric-Affine Spaces, we present the most general…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Damianos Iosifidis

Within the framework of the Finslerian approach to the problem of violation of Lorentz symmetry, consideration is given to a flat axially symmetric Finslerian space of events, which is the generalization of Minkowski space. Such an event…

High Energy Physics - Theory · Physics 2008-11-26 G. Yu. Bogoslovsky

We introduce a novel method to circumvent Weinberg's no-go theorem for self-tuning the cosmological vacuum energy: a Lorentz-violating finite-temperature superfluid can counter the effects of an arbitrarily large cosmological constant.…

High Energy Physics - Theory · Physics 2018-08-20 Justin Khoury , Jeremy Sakstein , Adam R. Solomon

We consider inhomogeneous viscous fluids in flat Friedmann-Robertson-Walker universe. We analyze different kinds of such fluids and investigate the possibility to reproduce the current cosmic acceleration providing a different future…

General Relativity and Quantum Cosmology · Physics 2015-09-21 Shynaray Myrzakul , Ratbay Myrzakulov , Lorenzo Sebastiani

We study some properties of a recently proposed local Lorentz Violating Finsler geometry, the so-called Bipartite space. This anisotropic structure deforms the causal null surface to an elliptic cone and provides an anisotropy to the…

High Energy Physics - Theory · Physics 2014-03-07 J. E. G. Silva , C. A. S. Almeida

We present a Friedmann-Robertson-Walker (FRW) quantum cosmological model within the framework of Finslerian geometry. In this work, we consider a specific fluid. We obtain the corresponding Wheeler-DeWitt equation as the usual constraint…

General Physics · Physics 2019-11-04 S S De , Farook Rahaman , Nupur Paul

Applying the cosmological principle to Finsler spacetimes, we identify the Lie Algebra of symmetry generators of spatially homogeneous and isotropic Finsler geometries, thus generalising Friedmann-Lema\^{i}tre-Robertson-Walker geometry. In…

General Relativity and Quantum Cosmology · Physics 2020-05-06 Manuel Hohmann , Christian Pfeifer , Nicoleta Voicu

We consider the diffeomorphism invariant gravity coupled with the ideal fluid in the non-standard way. The Lorentz-invariance of the graviton propagator in such a theory considered as perturbation over flat background turns out to be broken…

High Energy Physics - Theory · Physics 2010-04-06 Shin'ichi Nojiri , Sergei D. Odintsov

We investigate the bounce cosmology induced by inhomogeneous viscous fluids in FRW space-time (non necessarly flat), taking into account the early-time acceleration after the bounce. Different forms for the scale factor and several examples…

General Relativity and Quantum Cosmology · Physics 2015-09-21 Ratbay Myrzakulov , Lorenzo Sebastiani

Finsler geometry is a natural and fundamental generalization of Riemann geometry, and is a tool to research Lorentz invariance violation. We find the connection between the most general modified dispersion relation and a pseudo-Finsler…

General Relativity and Quantum Cosmology · Physics 2023-05-02 Jie Zhu , Bo-Qiang Ma

The concept of smooth deformation of Riemannian manifolds associated with the extrinsic curvature is explained and applied to the FLRW cosmology. We show that such deformation can be derived from Einstein-Hilbert-like dynamical principle…

General Relativity and Quantum Cosmology · Physics 2017-04-06 Abraao J. S. Capistrano , Luiz A. Cabral

We present fully nonlinear and exact cosmological perturbation equations in the presence of multiple components of fluids and minimally coupled scalar fields. We ignore the tensor-type perturbation. The equations are presented without…

General Relativity and Quantum Cosmology · Physics 2015-11-05 Jai-chan Hwang , Hyerim Noh , Chan-Gyung Park

Granted the post-Lorentzian relativistic kinematic transformations are described in the Finslerian framework, the uniformity between the actual light velocity anisotropy change and the anisotropic deformation of measuring rods can be the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. S. Asanov

We outline how the symmetry groups of spacetime are interpreted in a gauge-theoretic approach. Specifically, we focus on the hypermomentum concept and discuss the hyperfluid, that appropriately generalizes the perfect (Euler) fluid of…

General Relativity and Quantum Cosmology · Physics 2023-11-07 Yuri N. Obukhov , Friedrich W. Hehl

In this work we investigate the anisotropic conformal structure of the gravitational field incorporating dark gravity in a generalized Lagrange geometric framework on the Lorentz tangent bundle and we present two applications; the…

General Relativity and Quantum Cosmology · Physics 2023-08-28 Christos Savvopoulos , Panayiotis Stavrinos

In a recent paper [Phys. Rev. D 92:084012, 2015], the author studied the classical $(1+1)$-dimensional Friedmann-Robertson-Walker (FRW) universe filled with a perfect fluid in Ho\v{r}ava-Lifshitz (HL) theory of gravity. This theory is…

General Relativity and Quantum Cosmology · Physics 2016-05-25 J. P. M. Pitelli

We consider a model of Quantum Gravity phenomenology, based on the idea that space-time may have some unknown granular structure that respects the Lorentz symmetry. The proposal involves non-trivial couplings of curvature to matter fields…

General Relativity and Quantum Cosmology · Physics 2008-01-21 Y. Bonder

A spherically symmetric comoving fluid solution of Einstein's equations is adapted for cosmological application by extending the geometry of standard FRW cosmology using a generalised curvature term. The resulting model retains many of the…

General Relativity and Quantum Cosmology · Physics 2009-09-15 Ron Wiltshire

Recent observations of ultra high energy cosmic rays and gamma rays suggest that there are small violations of Lorentz symmetry. If there were no such violations, then the GZK cut off would hold and cosmic rays with energy $\sim 10^{20}eV$…

General Physics · Physics 2007-05-23 B. G. Sidharth

The $(1+1)$-dimensional Friedmann-Robertson-Walker (FRW) universe filled with a perfect fluid with equation of state $p=\omega \rho$ is analyzed through the view of Ho\v rava-Lifshitz (HL) theory of gravity. In this theory, the anisotropic…

General Relativity and Quantum Cosmology · Physics 2016-05-09 J. P. M. Pitelli