Part 3/8:
O'Dowd emphasizes that while many systems obey these rules, there exists a fragile balance between forward determinism in time and the conservation of information concerning the past.
Causal Determinism vs. Time-Reversal Symmetry
An important distinction made in the discussion is between causal determinism — the idea that knowing the present can predict the future — and time-reversal symmetry, which allows for the reconstruction of the past. A nuanced example illustrates this: if two different states (A and B) can lead to the same outcome (C), knowing the present condition C doesn't inform us precisely which state's past configuration brought it about. Hence, information about the initial state is obscured.