I was watching a Youtube video and the narrator mentioned that sometimes antimatter can be thought of matter traveling backwards in time and that confused me. I started thinking about what time is and it doesn't make any sense that antimatter acts in any way like it's traveling backwards in time. Wouldn't that imply gravity would be reversed and even weirder, it'd entropy backwards? That got me thinking that I can define the direction of time by which way entropy points and it's possible that everything we observer seems to only travel in one chronological direction simply because we can only observe things that experience entropy. That got me wondering if the rate of entropy changes, so I googled entropy and relativity together and was surprised to find that I don't see any formulations of entropy that includes relativity. Could time dilation be thought of as changes in the rate of entropy? I tried to continue my thought process to see other manifestations of such things and I also realized that faster entropy in one location over another would cause objects to drift, just like gravity. So then I googled entropy gravity and found a few articles. Is this an active area of research in physics or has the idea since been thrown out? And why does the equation of entropy not have any reference to the curvature of space? It seems that the more space is curved, the slower the rate of entropy.