Time flies by when you are happy, engaged, enjoying etc. and slows down to a crawl when you have extreme pain. More than the ‘proportional theory’ of time’ these experiences seem to have congruence with the general theory of relativity which states “spending 1hr with a loved one would feel like 5-10mins”. In the clock time sense, the theory states that – heavier objects warp space-time and slow down time. Like if you stand next to the pyramid in Egypt, time should be slower for you compared to a person standing far away. I guess time perception is more important than actual time passed since that is what would impact you. I think time perception would be related to how much new information you’re processing from the environment. If the environment is all familiar and you are doing the same things that you’ve been doing for ages, time seems to go by very fast since there is very little new information added. It is also a factor of how aware you are at the present moment with respect to your surroundings and body. Things in the environment need to really captivate your interest to that extent for you to feel time slow down. Time would thus essentially be the slowest when EVERYTHING is new around you and when you are most intrigued by them.
Maybe at the time you were just born or if you visit an alien planet which is fundamentally different in every aspect compared to ours. Even a 1 day visit to such a planet would be the information equivalent of a month or more on earth. Traveling to a new place should slow down time too. Office is the most common environment where time starts to go very fast once you get accustomed to the job. Months pass by and you kind of have a feeling your losing control. Day -dreaming surprisingly makes time pass real quick. Maybe because no new information is added during day dreaming, in retrospect nothing much is remembered and hence we feel the time just flew by.
It is also said that, emotions like fear collapse time while awe expands it. It is also said that for stress free productivity you need to be relaxed first. So maybe relaxation without reduction in alertness should also slow time. The difficult part is that when we think of relaxation we conjure up states of mild hypnosis and stupor, but it is actually possible to get relaxed w/o compromising on alertness. Ive noticed this while drinking alcohol(assuming you’ve already had more than enough sleep to start with). The relaxation greatly increases without compromising attention. Another thing that comes to my mind is martial arts and sports when I think of time perception or speed of perception. In shaolin kung-fu and even bruce lee’s jee kwon do it is emphasized that you need to turn off your mind and stay in a no mind state. Maybe we need to turn off the thinking mind to greatly increase our perception of time. Marital art masters train their reflexes and speed of perception to a level of 0.1sec response. That is if an average person’s movements(0.3sec) would appear to be 3 times slower to the master. Martial arts is a very intriguing discipline as it trains both the mind and body.