According to Einstein's special theory of relativity, which of the following is true? The speed of light starts at 3.0 E 8 m/s, but then increases due to red shifts. Time speeds up or slows, depending on how fast something is moving relative to something else. All the laws of physics are the same only for frames of reference at rest, but not those in constant velocity. Inertial frames of reference are at rest, while kinetic frames of reference are moving with constant velocity