Linear perturbations of symmetric teleparallel gravity on Minkowski background

Symmetric teleparallel gravity (STG) can be regarded as a modified gravity theory that lacks diffeomorphism symmetries, which complicates the calculation of its degrees of freedom. In this study, we analyze the linear perturbations of general STG models on a Minkowski background, considering both scenarios with and without scalar couplings. Furthermore, we provide lower bounds for the number of degrees of freedom associated with each model.