Albert Einstein's special theory of relativity, published in 1905, predicts unusual counterintuitive effects that occur when objects are traveling close to the speed of light, including:
- Lorentz contraction
- time dilation
- mass increase with speed
- the speed of light as the ultimate speed limit
- mass energy equivalency, E=mc²
Speed of Light as a Fundamental Constant
Einstein based his theory of special relativity on the assumption that the speed of light in a vacuum is a fundamental constant. Hence, all nonaccelerating observers measure the same value for the speed of a light beam regardless of their velocity.
Prior to Einstein's special relativity theory and the Michelson-Morley experiment, physicists thought that observers moving at different velocities would measure different values for the speed of light.
