Definition

Noun: 1. The speed at which light travels in a vacuum: This is a fundamental constant of nature, representing the maximum speed at which all conventional matter and information in the universe can travel. It is defined as exactly 299,792,458 meters per second.

Usage Examples

• Noun:
  • Nothing with mass can travel at light speed.
  • The theory of relativity is based on the principle that light speed is constant for all observers.
  • Scientists measured the distance using the known value of light speed.

Advanced Usage

• "faster-than-light": A theoretical concept describing speeds exceeding the speed of light, often abbreviated as . This is not currently possible according to established physics.
  • Warp drive is a science-fiction concept for faster-than-light travel.
• In scientific contexts, it is often denoted by the lowercase letter c.
  • The famous equation E=mc² uses c to represent the speed of light.

Variants and Related Words

• Speed of light: This is the full, more formal term and is perfectly synonymous with "light speed."
  • The speed of light is a universal constant.
• c (symbol): The standard scientific symbol for the speed of light in a vacuum.

Synonyms

• Velocity of light: A more technical synonym, emphasizing it as a vector quantity (though its magnitude is constant).
• Cosmic speed limit: An informal term highlighting its role as the universe's maximum speed.

Related Phrases

• At light speed: Moving or occurring at this velocity. Often used figuratively.
  • The news spread at light speed across the internet.
• Approach light speed: To travel at a velocity very close to, but still less than, .
  • As particles approach light speed, their mass effectively increases.

Noun

1. the speed at which light travels in a vacuum; the constancy and universality of the speed of light is recognized by defining it to be exactly 299,792,458 meters per second