- #1
Jehannum
- 102
- 26
- TL;DR Summary
- I'm interested in separating out things that can be observed by looking at a picture of the universe at a single moment in time, and things that can't
If we took a snapshot of the entire universe (or if we stopped time) but still had the power to move around and measure, we could observe static properties such as:
Mass
Force
Position
From the above, we would be able to infer acceleration. But we couldn't observe present velocity and therefore kinetic energy or momentum.
Therefore the state of the universe isn't fully encoded in its own three dimensions. Yet, if we were to restart the universe, objects would move at their previous velocity.
Where is this extra information "stored"?
What is the fundamental difference between properties that can be measured in the snapshot (e.g. mass) and those that can't (velocity)?
Is the answer simply "spacetime"?
Mass
Force
Position
From the above, we would be able to infer acceleration. But we couldn't observe present velocity and therefore kinetic energy or momentum.
Therefore the state of the universe isn't fully encoded in its own three dimensions. Yet, if we were to restart the universe, objects would move at their previous velocity.
Where is this extra information "stored"?
What is the fundamental difference between properties that can be measured in the snapshot (e.g. mass) and those that can't (velocity)?
Is the answer simply "spacetime"?