I had always thought of this as sort of a pseudo-problem. After all, I would think, why shouldn't the dynamical laws be symmetric wrt time-reversal. As John Baez stated in a review of H. D. Zeh's The Physical Basis of the Direction of Time (which I haven't read) http://math.ucr.edu/home/baez/time/time.html: "Our world is evidently in a state that is not even approximately invariant under time reversal; there are many processes going on whose time-reversed versions never seem to happen. But this is logically independent from the question of whether the dynamical laws of physics admit time reversal symmetry." Which seemed to reinforce my notion that the time reversal asymmetry of the world isn't necessarily in conflict with the time reversal symmetry of dynamical laws. But at the end of the review he states: "The main remaining mystery, then, is why the state of the universe is grossly asymmetric under time reversal, even though the dynamical laws of physics are almost - but not quite! - symmetric." Did I miss something in Baez' review. If the time reversal asymmetry of the world and the time reversal symmetry of the dynamical laws are logically independent, then what exactly is the problem? Is it that physics doesn't offer an underlying general dynamic for the apparently pervasive time reversal asymmetry of the physical universe? Or is it more complicated than that? Thanks in advance for any comments.