TY  - JOUR
AU  - Bombacigno, F.
AU  - Boudet, S.
AU  - Montani, G.
PY  - 2021
DA  - 2021//
TI  - Generalized Ashtekar variables for Palatini f(R) models
T2  - Nucl. Phys. B
JO  - Nuclear Physics B
SP  - 115281
EP  - 21pp
VL  - 963
PB  - Elsevier
AB  - We consider special classes of Palatini f(R) theories, featured by additional Loop Quantum Gravity inspired terms, with the aim of identifying a set of modified Ashtekar canonical variables, which still preserve the SU(2) gauge structure of the standard theory. In particular, we allow for affine connection to be endowed with torsion, which turns out to depend on the additional scalar degree affecting Palatini f( R) gravity, and in this respect we successfully construct a novel Gauss constraint. We analyze the role of the additional scalar field, outlining as it acquires a dynamical character by virtue of a non vanishing Immirzi parameter, and we describe some possible effects on the area operator stemming from such a revised theoretical framework. Finally, we compare our results with earlier studies in literature, discussing differences between metric and Palatini approaches. It is worth noting how the Hamiltonian turns out to be different in the two cases. The results can be reconciled when the analysis is performed in the Einstein frame.
SN  - 0550-3213
UR  - https://arxiv.org/abs/1911.09066
UR  - https://doi.org/10.1016/j.nuclphysb.2020.115281
DO  - 10.1016/j.nuclphysb.2020.115281
LA  - English
N1  - WOS:000613579500003
ID  - Bombacigno_etal2021
ER  -