But that is just a selfish hope for free will to exist.
think about it:
taps head
If it's a time 'line' then you don't get to pick your direction - no choice is no free will, only if a line exists in a plane does choice come into the picture. /s
Why is time "constrained" as a dimension, that is, you can only move one direction through time, why?
So thinking about how to constrain a dimension, I thought of black holes, once you pass the event horizon they remove half a dimension,
This then makes me think of the big bang and why is it not a black hole? the entire mass of the universe in one place... suspicious, then I think... what if it is a black hole(ish) and we(and the entire known universe) are in the event . horizon and the dimension constrained we perceive as time. and each layer of event horizon constrains another dimension.
At which point I usually fall asleep.
The way I think about time (also probably wrong and not nuanced enough) is through the energy of a system (entropy?). Essentially if the whole universe operates on a tick based update system, then moving from one state to the next is all about how various particles interact with each other. And this in general would be particles moving from a higher entropy state to a lower entropy state. So effectively to go back in time you'd need a lot of energy to undo all the chemical reactions / potential to kinetic energy conversions etc. that caused us to go from one state to the next. So even if it was possible to undo the appropriate state changes using some magic machine, there wouldn't be energy to do it
Now what's really mind blowing is that if such a machine was operating on you, you might still be conscious in a potentially horrifying way. The conclusions of your thoughts come before the thoughs that triggered them, and then they melt away into the thoughts that will trigger them...