T. Harko, T. S. Koivisto, G. J. Olmo, F. S. N. Lobo, D. Rubiera-Garcia
We present a novel theory of gravity, namely, an extension of symmetric teleparallel gravity. This is done by introducing a new class of theories where the nonmetricity Q is coupled nonminimally to the matter Lagrangian. This nonminimal coupling entails the nonconservation of the energy-momentum tensor, and consequently the appearance of an extra force. We also present several cosmological applications.
Modified gravity; nonmetricity; cosmology
The Fifteenth Marcel Grossmann Meeting
Elia S Battistelli, Robert T Jantzen, Remo Ruffini
World Scientific Publishing Co. Pte. Ltd., Page 410