# Definition of "timelike" [timelike]

- (adjective) Of a four-vector in representing a point in spacetime, having a positive four-vector norm.

- (adjective) (of the interval between two events in spacetime) Having overlapping light cones, so that information can pass from one to the other, and one can be envisaged as a cause of the other.

## Use "timelike" in a sentence

- "The far future of our universe is therefore representable by de Sitter space-time, and in this type of space-time the future timelike boundary is a spacelike hypersurface."
- "Now, in an open or flat Friedmann-Robertson-Walker cosmological model with no cosmological constant, whilst the past 'Big-Bang' singularity corresponds to a spacelike hypersurface in the boundary of the conformal compactification, the future timelike infinity corresponds to a single point."
- "The boundary of the conformal compactification contains components which correspond to singularities, and components which correspond to spacelike infinity, timelike infinity, (and null infinity)."