# 28th Texas Symposium on Relativistic Astrophysics

13-18 December 2015
International Conference Centre Geneva
Europe/Zurich timezone

## A Palatini formalism for MOND in $f(\chi)$ gravity

15 Dec 2015, 18:22
3m
Level 2, Room 14 (International Conference Centre Geneva)

### Speaker

Ernesto Barrientos Rodríguez (Universidad Nacional Autónoma de México)

### Description

In this work we construct a relativistic extension of the MODified Newtonian Dynamics (MOND) in the metric formalism $f(\chi)$ using the Palatini approach. We show that a simple power law: $f(\chi)=\chi^b$, with $b = 3/2$ corresponds to the non-relativistic form of MOND. Amongst the many approaches proposed to extend MOND to a relativistic regime, the Palatini metric formalism discussed here, yields second order field equations, which is a desirable (but not a necessary) requirement in a gravitational theory. We briefly discuss lensing applications of this proposal.

### Primary author

Ernesto Barrientos Rodríguez (Universidad Nacional Autónoma de México)