Full Idea
We could say that what we call the past is just the direction towards (for instance) decreasing entropy, and the direction we call the future is the direction towards increasing entropy.
Gist of Idea
Maybe the past is just the direction of decreasing entropy
Source
Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 5.3.3)
Book Reference
Baron,S/Miller,K: 'Introduction to the Philosophy of Time' [Polity 2019], p.133
A Reaction
One problem is that locally entropy can sometimes go the other way, which would imply local pockets with a reversed time's arrow,.