On the "Legendre scalarization" of nonlinear gravity theories
General Relativity and Quantum Cosmology
2024-01-22 v1
Abstract
We discuss the proposal of a new method to transform a f(R) metric gravity theory into a general relativistic theory including an auxiliary scalar field, recently introduced by S. Cotsakis et al. We argue that (i) the fact that the fourth order equations of f(R) metric gravity can be recast (via a Legendre transformation) into Einstein equations without any conformal rescaling has been thoroughly clarified in the previous literature, and (ii) the newly proposed method produces a set of equations that are not equivalent to the original theory. In the conclusion, a comment is added on another aspect of the Legendre transformation which seems to be generally overlooked.
Cite
@article{arxiv.2308.05854,
title = {On the "Legendre scalarization" of nonlinear gravity theories},
author = {Guido Magnano},
journal= {arXiv preprint arXiv:2308.05854},
year = {2024}
}