←back to thread

Time is a dimension, but not like space

(bigthink.com)
171 points belter | 1 comments | 17 Oct 24 15:29 UTC | HN request time: 0.201s | source
Show context
IgorPartola ◴[20 Oct 24 14:13 UTC] No.41895504[source]▶
If I understand correctly, we experience time at nearly the speed of light. What I mean by that is that any particle’s 4 dimensional velocity vector has the magnitude of c which means that if it is mostly at rest in space then time has to be the major contributing factor but the magnitude of the vector. On the other hand something like a photon experiences to time at all as it moves through the 3 space dimensions at a total of c.
replies(7): >>41895838 #>>41895843 #>>41895992 #>>41896270 #>>41897669 #>>41897752 #>>41902254 #
1. scotty79 ◴[21 Oct 24 09:31 UTC] No.41902254[source]▶
It's better to think that our 4 velocity always has a magnitude of 1 and use c only as a scaling factor necessary because our weird choice to use different units for time and space.

Acceleration is a rotation in this weird 3+it dimensions.

I think it better to think about 4 velocity as a unitless quantity. Because our intuitions about units and dimensions are formed by 3 dimensional space where every dimension can be swapped with any other and everything is still the same. 1 meter rotated is still 1 meter. Doesn't become 0.56m/s