- #1
Dmitry67
- 2,567
- 1
Say, we have empty flat spacetime; there is a lab frame and 2 particles - bradyon and tachyon. While movement of bradyon is stable, tachyon is believed to lose energy because of Cherenkov radiation:
http://en.wikipedia.org/wiki/Tachyon#Cherenkov_radiation
if it is charged and even if it is not (gravitational cherenkov radiation). So there is an intristic assymetry between timelike trajectories of bradyons, which are stable, and spacelike trajectories of tachyons, which are not.
However, the metrics itself, if we take 2-D space is symmetric between space and time:
s^2 = r^2 - t^2
Question:
Is the symmetry I described above an indirect result of having more spatial dimensions than time dimensions (3 vs 1), or you need some extra assumptions (like arrow of time) to explain it?
http://en.wikipedia.org/wiki/Tachyon#Cherenkov_radiation
if it is charged and even if it is not (gravitational cherenkov radiation). So there is an intristic assymetry between timelike trajectories of bradyons, which are stable, and spacelike trajectories of tachyons, which are not.
However, the metrics itself, if we take 2-D space is symmetric between space and time:
s^2 = r^2 - t^2
Question:
Is the symmetry I described above an indirect result of having more spatial dimensions than time dimensions (3 vs 1), or you need some extra assumptions (like arrow of time) to explain it?