TY  - JOUR
AU  - Izadi, A.
AU  - Shacker, S. S.
AU  - Olmo, G. J.
AU  - Banerjee, R.
PY  - 2018
DA  - 2018//
TI  - Observational effects of varying speed of light in quadratic gravity cosmological models
T2  - Int. J. Geom. Methods Mod. Phys.
JO  - International Journal of Geometric Methods in Modern Physics
SP  - 1850084 - 16pp
VL  - 15
IS  - 5
PB  - World Scientific Publ Co Pte Ltd
KW  - Palatini formalism
KW  - modified gravity
KW  - causal structure constant
KW  - varying speed of light
AB  - We study different manifestations of the speed of light in theories of gravity where metric and connection are regarded as independent fields. We find that for a generic gravity theory in a frame with locally vanishing affine connection, the usual degeneracy between different manifestations of the speed of light is broken. In particular, the space-time causal structure constant (c(ST)) may become variable in that local frame. For theories of the form f(R, R-mu nu R-mu nu), this variation in c(ST) has an impact on the definition of the luminosity distance (and distance modulus), which can be used to confront the predictions of particular models against Supernovae type Ia (SN Ia) data. We carry out this test for a quadratic gravity model without cosmological constant assuming (i) a constant speed of light and (ii) a varying speed of light (VSL), and find that the latter scenario is favored by the data.
SN  - 0219-8878
UR  - http://arxiv.org/abs/1701.06923
UR  - https://doi.org/10.1142/S0219887818500846
DO  - 10.1142/S0219887818500846
LA  - English
N1  - WOS:000429106400016
ID  - Izadi_etal2018
ER  -