  We investigate scalar-tensor theories, motivated by dark energy models, in
the strong gravity regime around the black hole at the centre of our galaxy. In
such theories general relativity is modified since the scalar field couples to
matter. We consider the most general conformal and disformal couplings of the
scalar field to matter to study the orbital behavior of the nearby stars around
the galactic star center $Sgr A^{*}$. Markov Chain Monte Carlo (MCMC)
simulation yields a bound on the parameters of the couplings of the scalar
field to matter. Using Bayesian Analysis yields the first constraints on such
theories in the strong gravity regime.
