TY  - JOUR
AU  - Delhom, A.
AU  - Mariz, T.
AU  - Nascimento, J. R.
AU  - Olmo, G. J.
AU  - Petrov, A. Y.
AU  - Porfirio, P. J.
PY  - 2022
DA  - 2022//
TI  - Spontaneous Lorentz symmetry breaking and one-loop effective action in the metric-affine bumblebee gravity
T2  - J. Cosmol. Astropart. Phys.
JO  - Journal of Cosmology and Astroparticle Physics
SP  - 018
EP  - 27pp
VL  - 07
IS  - 7
PB  - IOP Publishing Ltd
KW  - gravity
KW  - modified gravity
KW  - quantum field theory on curved space
KW  - Quantum fields in curved spacetimes
AB  - The metric-affine bumblebee model in the presence of fermionic matter minimally coupled to the connection is studied. We show that the model admits an Einstein frame representation in which the matter sector is described by a non-minimal Dirac action without any analogy in the literature. Such non-minimal terms involve unconventional couplings between the bumblebee and the fermion field. We then rewrite the quadratic fermion action in the Einstein frame in the basis of 16 Dirac matrices in order to identify the coefficients for Lorentz/CPT violation in all orders of the non-minimal coupling xi. The exact result for the fermionic determinant in the Einstein frame, including all orders in xi, is also provided. We demonstrate that the axial contributions are at least of second order in the perturbative expansion of xi. Furthermore, we compute the one-loop effective potential within the weak field approximation.
SN  - 1475-7516
UR  - https://arxiv.org/abs/2202.11613
UR  - https://doi.org/10.1088/1475-7516/2022/07/018
DO  - 10.1088/1475-7516/2022/07/018
LA  - English
N1  - WOS:000834157900011
ID  - Delhom_etal2022
ER  -