The self-accelerating universe with vectors in massive gravity

We consider the model of modified gravity with dynamical torsion. This model was found to have promising stability properties about various backgrounds. The model admits a self-accelerating solution. We have shown previously that if the parameters are adjusted in such a way that the torsion is much greater than the effective cosmological constant, the self-accelerating solution is unstable: there are exponentially growing modes. Here, we study the scalar perturbations in the case when the torsion is of the order of the effective cosmological constant. We find that there are no exponential instabilities.

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Partially massless theory in three dimensions and self-dual massive gravity

Modern Physics Letters A ◽

10.1142/s0217732318500670 ◽

2018 ◽

Vol 33 (12) ◽

pp. 1850067 ◽

Cited By ~ 1

Author(s):

Daniel Galviz ◽

Adel Khoudeir

Keyword(s):

Scalar Field ◽

Physical System ◽

Higher Dimensions ◽

Massive Gravity ◽

Degree Of Freedom ◽

The Self ◽

Three Dimensions ◽

Massless Theory ◽

Chern Simons ◽

Topologically Massive Gravity

Partially massless theory in three dimensions is revisited and its relationship with the self-dual massive gravity is considered. The only mode of the partially massless theory is shown explicitly through an action for a scalar field on (A)dS background. This fact can be generalized to higher dimensions. This degree of freedom is altered when a triadic Chern–Simons is introduced, giving rise to the self-dual massive gravity on (A)dS background. We present another physical system with partially massless symmetry and its connection with topologically massive gravity is discussed.

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Minimal theory of massive gravity and constraints on the graviton mass

Journal of Cosmology and Astroparticle Physics ◽

10.1088/1475-7516/2021/12/011 ◽

2021 ◽

Vol 2021 (12) ◽

pp. 011

Author(s):

Antonio De Felice ◽

Shinji Mukohyama ◽

Masroor C. Pookkillath

Keyword(s):

General Relativity ◽

Upper Bound ◽

Massive Gravity ◽

The Self ◽

Data Sets ◽

Graviton Mass ◽

Minimal Theory ◽

Linear Perturbations ◽

Normal Branch ◽

The One

Abstract The Minimal theory of Massive Gravity (MTMG) is endowed non-linearly with only two tensor modes in the gravity sector which acquire a non-zero mass. On a homogeneous and isotropic background the theory is known to possess two branches: the self-accelerating branch with a phenomenology in cosmology which, except for the mass of the tensor modes, exactly matches the one of ΛCDM; and the normal branch which instead shows deviation from General Relativity in terms of both background and linear perturbations dynamics. For the latter branch we study using several early and late times data sets the constraints on today's value of the graviton mass μ0, finding that (μ0/H 0)2 = 0.119-0.098 +0.12 at 68% CL, which in turn gives an upper bound at 95% CL as μ0 < 8.4 × 10-34 eV. This corresponds to the strongest bound on the mass of the graviton for the normal branch of MTMG.

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SELF-ACCELERATING UNIVERSE IN NONLINEAR MASSIVE GRAVITY

Modern Physics Letters A ◽

10.1142/s0217732313400166 ◽

2013 ◽

Vol 28 (03) ◽

pp. 1340016 ◽

Cited By ~ 4

Author(s):

A. E. GUMRUKCUOGLU ◽

C. LIN ◽

S. MUKOHYAMA

Keyword(s):

Wave Spectrum ◽

Background Level ◽

Mass Term ◽

Constant Term ◽

Massive Gravity ◽

Accelerating Universe ◽

Effective Cosmological Constant ◽

De Rham ◽

Mass Terms ◽

MASTER ACTIONS FOR LINEARIZED MASSIVE GRAVITY MODELS IN 3D

International Journal of Modern Physics A ◽

10.1142/s0217751x12500157 ◽

2012 ◽

Vol 27 (03n04) ◽

pp. 1250015 ◽

Cited By ~ 3

Author(s):

PIO J. ARIAS ◽

ADEL KHOUDEIR ◽

J. STEPHANY

Keyword(s):

Fourth Order ◽

General Model ◽

Massive Gravity ◽

Second Order ◽

The Self ◽

Gravity Models ◽

Order Model ◽

Duality Transformation ◽

First Order ◽

Chern Simons

We present a unified analysis of the self-dual, second order, topologically massive and the recently introduced fourth-order models of massive gravity in 3D. We show that there is a family of first-order actions which interpolate between these different single excitation models. We show how the master actions are related by duality transformation. We construct by the same method the master action which relates the fourth-order new massive model with two excitations and the usual second-order model with Fierz–Pauli mass. We show that the more general model obtained by adding a Chern–Simons term to the new massive model is equivalent off-shell to the second-order spontaneously broken linearized massive gravity.

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The stability of self-accelerating Universe in modified gravity with dynamical torsion

International Journal of Modern Physics A ◽

10.1142/s0217751x17501378 ◽

2017 ◽

Vol 32 (23n24) ◽

pp. 1750137 ◽

Cited By ~ 5

Author(s):

Vasilisa Nikiforova

Keyword(s):

Cosmological Constant ◽

Modified Gravity ◽

Degrees Of Freedom ◽

The Self ◽

Accelerating Universe ◽

Effective Cosmological Constant ◽

Linear Perturbations ◽

The Stability ◽

Scalar Sector ◽

Rule Out

We consider the model of modified gravity with dynamical torsion. This model was previously found to have promising stability properties about various backgrounds. Here, we study the stability of linear perturbations about the self-accelerating solution. We apply the (3[Formula: see text]+[Formula: see text]1)-decomposition and consider the scalar sector of perturbations. We find that the number of degrees of freedom is equal to 2, which is the same as in Minkowski background. However, there is at least one instability in the scalar sector, if the value of background torsion is large enough. This does not rule out the possibility of stable self-acceleration with torsion of the order of the effective cosmological constant.

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