I am an amateur physics enthusiast and a science fiction writer who also sometimes writes factual articles. I like to inspire lay people to get interested in the big scientific problems and am currently writing a sort of primer on the question of time. Getting across the basic ideas is the most important thing and I add disclaimers saying that what I'm writing is at best only part of the truth.
I'm thinking about the question is there really an arrow of time? So far all the arrows turn out to be illusory. Physical processes are time symmetrical, even entropy may be a double headed arrow. Quantum mechanics also involves time reversible processes and maths. I believe there are several proposals to explain the collapse of a wave function and some of them are time symmetrical, some aren't. I'd be happy to read more thoughts on the time symmetry of collapse, in layman's terms, but I'm not trying to get the full story here, I want to follow a particular train of though, without saying anything that's wrong.
It seems to me that a wave function contains a lot of information because it tells you the probability of a particle being in any location, while after the collapse you only have binary information for all possible locations - the particle is there or not there. Therefore information is lost and the process appears to be non-reversible.
I realise that the wave function can be represented by a curve and that curves can be represented by formulas – so maybe the wave function is effectively compressed information and does not really contain more data?
I'll be grateful for any thoughts.