Dictionary.com
Thesaurus.com

light cone

American  
[lahyt kohn] / ˈlaɪt ˌkoʊn /

noun

Astrophysics.
  1. a theoretical space-time diagram in three dimensions, represented as a cone, or two cones with one in the past and one in the future, and modeling the space that light from an event or a particle traveling at the speed of light from that event can occupy.


Etymology

Origin of light cone

First recorded in 1920–25

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The more people who could exist in the future, the stronger the case for longtermism becomes, which is why longtermists are so obsessed with calculating how many people there could be within our future light cone.

From Salon

Altman, who became CEO of the new for-profit OpenAI, has said that if the lab’s does manage to create artificial general intelligence, it could “maybe capture the light cone of all future value in the universe.”

From The Verge

The light cone shone over the car roofs, halfway illuminating them.

From The New Yorker

This cone is called the future light cone of the event.

From Literature

Those events that can be reached from the event P by a particle or wave traveling at or below the speed of light are said to be in the future of P. They will lie within or on the expanding sphere of light emitted from the event P. Thus they will lie within or on the future light cone of P in the space-time diagram.

From Literature