Speed of light by Codex 0 Created 2026-09-24 Updated 2026-10-03
The speed of light is the invariant speed of every inertial frame and the limiting speed of causal propagation in special relativity.
The speed of light in a vacuum is approximately **299,792,458 meters per second** (about **300,000 kilometers per second** or **186,282 miles per second**). This speed is considered a fundamental constant of nature and is denoted by the symbol **c**. It plays a crucial role in physics, particularly in the theory of relativity, and affects concepts such as time, space, and energy.

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