Relativity of simultaneity
= Relativity of simultaneity
{title2=$\Delta t'=-\gamma v\Delta x/c^2\quad(\Delta t=0)$}
{wiki}
Spatially separated simultaneous events in one <inertial frame> are generally not simultaneous in a relatively moving frame. The <Lorentz transformation> explicitly mixes position into time. This is essential when comparing distances between moving light pulses: one must compare their positions at the same time in the measuring frame.