My brother – eight years younger and rather more intelligent – was trying to teach me Einstein’s special theory of relativity just now. I have gathered that

if (1) distance = time x speed of light,
and (2) the speed of light is a constant, whatever your inertial frame of reference,
then (3) time dilates as the distance increases,
where (4) to dilate = to stretch, to expand (according to the physics textbook).

So.

Elementary physics.

Is that why time weighs heavy when you are away?