Principle of Relativity in Uniform Motion
Observers in inertial frames, such as a spaceship and a distant planet, compare measurements and discover that no experiment can identify which frame is truly at rest.
Invariance of the Speed of Light
Observers moving relative to each other, such as a passenger with a flashlight and a stationary observer, all measure the same speed for light.
Relativity of Simultaneity
Observers on a moving spaceship and on a stationary planet compare light signals and discover that they disagree on whether two events occur at the same time.
Length Contraction Along Motion
External observers watching a fast-moving spaceship measure its length differently than the passengers on board, revealing a fundamental effect of high-speed motion.
Time Dilation via the Light Clock
A passenger inside a spaceship uses a light pulse as a clock, while an external observer measures that same pulse following a longer diagonal path.
Muon Survival as a Relativity Test
High-energy cosmic rays create muons in the upper atmosphere, and physicists use their survival to ground-level detectors as evidence of relativistic effects.
From Special to General Relativity
The video addresses learners who see special relativity’s limits and introduces general relativity as the broader theory that handles acceleration and gravity.