Free will is not compatible with a deterministic universe governed by linear causality. This camp proposes that non-linear causality is alive and well in our brains and similar devices and it is this that characterises free will.
In order to accommodate loops in causality, time must have a second dimension. Standard physics assumes one dimensional time so the present is but a point in time and thus there is no room for free will (or the conscious now in fact). What devices like the brain do is expand the conventional point in time into the now of consciousness. We then have the opportunity to make choices.