  We derive a general expression for the large-scale halo bias, in theories
with a scale-dependent linear growth, using the excursion set formalism. Such
theories include modified gravity models, and models in which the dark energy
clustering is non-negligible. A scale dependence is imprinted in both the
formation and evolved biases by the scale-dependent growth. Mergers are
accounted for in our derivation, which thus extends earlier work which focused
on passive evolution. There is a simple analytic form for the bias for those
theories in which the nonlinear collapse of perturbations is approximately the
same as in general relativity. As an illustration, we apply our results to a
simple Yukawa modification of gravity, and use SDSS measurements of the
clustering of luminous red galaxies to constrain the theory's parameters.

Cosmology and Nongalactic Astrophysics