http://arxiv.org/abs/1407.3384 Why do we remember the past and not the future? The 'time oriented coarse graining' hypothesis Phenomenological arrows of time can be traced to a past low-entropy state. Does this imply the universe was in an improbable state in the past? I suggest a different possibility: past low-entropy depends on the coarse-graining implicit in our definition of entropy. This, in turn depends on our physical coupling to the rest of the world. I conjecture that any generic motion of a sufficiently rich system satisfies the second law of thermodynamics, in either direction of time, for some choice of macroscopic observables. The low entropy of the past could then be due to the way we couple to the universe (a way needed for us doing what we do), hence to our natural macroscopic variables, rather than to a strange past microstate of the world at large. Is Rovelli saying that the low entropy state of the universe plusminus 13.7 bilion years ago is not the whole story ? I don't fully understand what he is trying capture here. Could t be that the discrete strutcture of the low entropy state universe thet whe vision after singularity or Bounce or whatever the universe state was 13.7 billion years ago, has something to do with our macroscopic ensemble view.