I am currently reading The road to reality by Roger Penrose. In chapter 27 he discusses time symmetry in dynamic evolution. He defines the Second Law of thermodynamics the following way:
Heat flows from a hotter to a colder body.
He states that this law implies time asymmetry: When you look at a system of two bodies, one colder than the other, the hotter body will become colder and the heat will transfer to the other body until they are in equilibrium. The system evolves perfectly deterministically. But when you look at the system backwards, the two bodies are in equilibrium and after some time suddenly one body will get colder and the other one will get hotter.
Now my question: In a universe where time evolution is reversed would such a process be perceived as a random process with no deterministic cause? In a two body system in equilibrium one body would suddenly get colder and the other one hotter. But in this universe it can not be determined which body will get colder and when - it is essentially a random process. If the theoretical inhabitants of this universe looked at this process backwards, they could not really recover the Second Law of Thermodynamics. From their viewpoint they could only state that the body that ends up hotter after the equilibrium breaks will get hotter.
Is it possible that there are such "hidden laws" that underlie a process, but cannot be determined because their dynamical evolution is hidden similarly to the process described above?