f(T) Gravity and local Lorentz invariance
Abstract
We show that in theories of generalised teleparallel gravity, whose Lagrangians are algebraic functions of the usual teleparallel Lagrangian, the action and the field equations are not invariant under local Lorentz transformations. We also argue that these theories appear to have extra degrees of freedom with respect to general relativity. The usual teleparallel Lagrangian, which has been extensively studied and leads to a theory dynamically equivalent to general relativity, is an exception. Both of these facts appear to have been overlooked in the recent literature on f(T) gravity, but are crucial for assessing the viability of these theories as alternative explanations for the acceleration of the universe.
Cite
@article{arxiv.1010.1041,
title = {f(T) Gravity and local Lorentz invariance},
author = {Baojiu Li and Thomas P. Sotiriou and John D. Barrow},
journal= {arXiv preprint arXiv:1010.1041},
year = {2012}
}
Comments
4 pages, no figure; v2: Added discussion about modifying the theory in order to make it manifestly Lorentz covariant and one reference; v3: minor changes to match published version