# Cosmological perturbations of unimodular gravity and general relativity are identical

@article{Basak2015CosmologicalPO, title={Cosmological perturbations of unimodular gravity and general relativity are identical}, author={Abhishek Basak and Oph'elia Fabre and S. Shankaranarayanan}, journal={General Relativity and Gravitation}, year={2015}, volume={48}, pages={1-30} }

Unimodular gravity (UG) is a restricted version of general relativity (GR) in which the variation of the metric determinant is set to zero and the field equations are given by the trace-free part of the full Einstein equations. The background equations in UG and GR are identical. It was recently claimed that the first order contribution in the temperature fluctuations of the Cosmic Microwave Background (CMB) in UG is different from GR. In this work, we calculate the first order perturbation…

## 18 Citations

### Diffusion in unimodular gravity: Analytical solutions, late-time acceleration, and cosmological constraints

- Physics
- 2020

Unimodular gravity is an appealing approach to address the cosmological constant problem. In this scenario, the vacuum energy density of quantum fields does not gravitate and the cosmological…

### The Universe acceleration from the Unimodular gravity view point: Background and linear perturbations

- PhysicsPhysics of the Dark Universe
- 2021

### Unimodular F(R) gravity

- Physics
- 2015

We extend the formalism of the Einstein-Hilbert unimodular gravity in the context of modified F(R) gravity. After appropriately modifying the Friedmann-Robertson-Walker metric in a way that it…

### Weyl relativity: a novel approach to Weyl's ideas

- Physics
- 2017

In this paper we revisit the motivation and construction of a unified theory of gravity and electromagnetism, following Weyl's insights regarding the appealing potential connection between the gauge…

### Nonconservative traceless type gravity

- PhysicsInternational Journal of Modern Physics D
- 2019

Extensions of the gravity theory in order to obtain traceless field equations have been widely considered in the literature. The leading example of such class of theories is the unimodular gravity,…

### Reissner Nordstrom Metric in Unimodular Theory of Gravity

- Physics
- 2016

We study the modified Reissner Nordstrom metric in the unimodular gravity. So far the spherical symmetric Einstein field equation in unimodular gravity has been studied in the absence of any source.…

### A reconstruction method for anisotropic universes in unimodular F(R)-gravity

- MathematicsThe European Physical Journal C
- 2022

An extension of unimodular Einsteinian gravity in the context of F(R) gravities is used to construct a class of anisotropic evolution scenarios. In unimodular GR the determinant of the metric is…

### Inflation in generalized unimodular gravity

- PhysicsPhysical Review D
- 2019

The recently suggested generalized unimodular gravity theory, which was originally put forward as a model of dark energy, can serve as a model of cosmological inflation driven by the effective…

### Unimodular f(G) gravity

- Physics
- 2016

In this paper we study a modified version of unimodular general relativity in the context of f(G), G denoting the Gauss–Bonnet invariant. We focus on Bianchi-type I and Friendmann–Robertson–Walker…

### Compact objects in unimodular gravity

- PhysicsJournal of Cosmology and Astroparticle Physics
- 2019

Unimodular gravity provides a theoretical framework that allows for non-conservation of energy-momentum, with possible implications for the cosmological constant problem. It is then important to…

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