# Unimodular gravity redux

@article{lvarez2015UnimodularGR, title={Unimodular gravity redux}, author={Enrique {\'A}lvarez and Sergio Gonz'alez-Mart'in and Mario Herrero-Valea and C. P. Mart'in}, journal={Physical Review D}, year={2015}, volume={92}, pages={061502} }

It is well known that the problem of the cosmological constant appears in a new light in unimodular gravity. In particular, the zero-momentum piece of the potential does not automatically produce a corresponding cosmological constant. Here we show that quantum corrections do not renormalize the classical value of this observable.

## 36 Citations

### Unimodular quantum gravity and the cosmological constant

- PhysicsFoundations of Physics
- 2018

It is shown that the one-loop effective action of unimodular gravity is the same as that of ordinary gravity, restricted to unimodular metrics. The only difference is in the treatment of the global…

### Unimodular Cosmological models

- Physics
- 2021

It is claimed that in the unimodular gravity framework the observational fact of exponential expansion of the universe cannot be taken as evidence for the presence for a cosmological constant or…

### Essential nature of Newton’s constant in unimodular gravity

- Physics
- 2015

We point out that in unimodular gravity Newton’s constant is an essential coupling, i.e. it is independent of field redefinitions. We illustrate the consequences of this fact by a calculation in a…

### The KLT relations in unimodular gravity

- Physics, Geology
- 2015

With this article, we initiate a systematic study of some of the symmetry properties of unimodular gravity, building on much of the known structure of general relativity, and utilising the powerful…

### Massive unimodular gravity

- Geology, PhysicsClassical and Quantum Gravity
- 2020

A ghost free massive deformation of unimodular gravity (UG), in the spirit of mimetic massive gravity, is shown to exist. This construction avoids the no-go theorem for a Fierz–Pauli type of mass…

### The cosmological constant as a boundary term

- PhysicsJournal of High Energy Physics
- 2022

Abstract
We compare the path integral for transition functions in unimodular gravity and in general relativity. In unimodular gravity the cosmological constant is a property of states that are…

### What do gravitons say about (unimodular) gravity?

- Physics, GeologyJournal of High Energy Physics
- 2018

A bstractWe revisit the problem of constraining the weak field limit of the gravitational lagrangian from S-matrix properties. From unitarity and Lorentz invariance of the S-matrix of massless…

### Can quantum fluctuations differentiate between standard and unimodular gravity?

- MathematicsJournal of High Energy Physics
- 2021

Abstract
We formally prove the existence of a quantization procedure that makes the path integral of a general diffeomorphism-invariant theory of gravity, with fixed total spacetime volume,…

### Covariant BRST quantization of unimodular gravity. II. Formulation with a vector antighost

- PhysicsPhysical Review D
- 2022

In our previous paper, we have presented a covariant BRST quantization of unimodular gravity which may account for the smallness of the cosmological constant, and we have shown that the physical…

### Unimodular trees versus Einstein trees

- Physics
- 2016

The maximally helicity violating tree-level scattering amplitudes involving three, four or five gravitons are worked out in Unimodular Gravity. They are found to coincide with the corresponding…

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