M theory

time before: only forwards, at a constant speed (1/4 dimension?).

time as 1/2 dimension: can go forward, at different speeds.

time as 1 dimension: can go forward and backward, and at different speeds.

time as 2 dimensions: you can redo a change you didnt like (as seen in CERNs photon experiments).

time as 3 dimensions: ???????????.

if time is a dimension, can we photograph it?

(weve got cameras to photograph gravitational waves, why not?).

time as 0 dimensions: motion is only the speed at which atoms move around.

absolute zero: no time.

black holes time: ????????

universe contracting in a big crush: what time?