(x1, ct1) = (25m, 25m) - What do the 'm' represent? (SR)

[seasponges]

I'm currently completing a special relativity assignment, and whenever coordinates are referred to they're represented as (x1, ct1) = (25m, 25m) or (6m, 2m). There are no units given (other than the 'm', and I highly doubt they're using minutes for ct). If someone could clear this up for me I'd be very grateful.

Cheers!

 

[arildno]

"m" as in Minkowski coordinates, perhaps?

ct has dimensions of length, btw.

Note that unless you work with the full 4-vector, it would be extremely easy for students to misunderstand the notation without the "m", falsely believing the time coordinate was a regular space coordinate.

 

[Sybren]

M for meter perhaps, since these have the dimension of length.

 

[AdamIsCylon]

Just to clarify, it is for "meters."

Spatial units are typically denoted in m, and I'm sure you've seen x represent a spatial coordinate.

ct is also meters, because c is the speed of light and c=3*10⁸ meters/second [m/s] except it is multiplied by time. So you have a velocity (c) times time.
(meters/seconds)*seconds=meters because the seconds cancel.

 

[seasponges]

Ha, it didn't occur to me ct was in meters (very new to SR). Thanks!