Definition of light cone in US English:

light cone


  • A surface in space-time, represented as a cone in three dimensions, comprising all the points from which a light signal would reach a given point (at the apex) simultaneously, and that therefore appear simultaneous to an observer at the apex.

    • ‘The future light cone represents the space that will eventually be filled by light emitted at that point.’
    • ‘But finally, the star may shrink in a way that the light cones will bend so much that they will not be able to escape.’
    • ‘His work on light cones, black holes, wormholes, and time travel were are extremely revolutionary.’
    • ‘Angular momentum can twist light cones and even make time travel possible in theory if not in practice.’
    • ‘The easiest way to describe light rays and light cones is through geometric optics.’