2 ms·
> That is, if I fire Alice light beam at you from a moving train, while Bob fires a beam at you from a platform, both beams will reach you at the same time. Th
by dnautics 6y ago
> That is, if I fire Alice light beam at you from a moving train, while Bob fires a beam at you from a platform, both beams will reach you at the same time.
That's wrong. Simultaneity is ill-defined in relativity.
The correct example is, "if Alice fires a light beam at you from a moving train and Bob fires a light beam from you from the platform, you will measure the Alice photons as going equally fast as the Bob photons.
- tsimionescu 6y agoAbsolute simultaneity is ill-defined, but simultaneity in my frame of reference does exist. However, you're right, your formulation is more precise, and actually possible to measure.