## SPACETIME

### Spacetime

In physics, spacetime is any mathematical model that combines space and time into a single continuum. Spacetime is usually interpreted with space as existing in three dimensions and time playing the role of a fourth dimension that is of a different sort from the spatial dimensions. From a Euclidean space perspective, the universe has three dimensions of space and one of time. By combining space and time into a single manifold, physicists have significantly simplified a large number of physical theories, as well as described in a more uniform way the workings of the universe at both the supergalactic and subatomic levels.

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### Space / Time

"Space" and "Time" are two mini-episodes of the British science fiction television series Doctor Who. They were broadcast on 18 March 2011 as part of BBC One's Red Nose Day telethon for the charity Comic Relief. The two mini-episodes were written by the programme's head writer Steven Moffat and directed by Richard Senior.

The above text is a snippet from Wikipedia: Space / Time

### spacetime

#### Noun

1. The four-dimensional continuum of the three spatial dimensions plus time.
An event is a point in spacetime, specified by the coordinates x,y,z and t.
2. An n-dimensional continuum consisting of dimensions of both space & time. Normally spacetime is considered as having 4 dimensions (x, y, z, t), but higher-dimensional spacetimes are often encountered in theoretical physics, e.g. the 5-dimensional spacetime of Kaluza-Klein theory or the 11 dimensions of spacetime in M-theory.
3. A specific region of the universe with mathematically different properties than the surrounding spacetime. Synonymous with "metric" within the context of general relativity.
"a Schwarzschild spacetime," "a Reissner-Nordstrom spacetime," etc. as opposed to sense (2) describing the universe's spacetime as a whole: "a Minkowski spacetime," "a 5-dimensional spacetime," etc.

The above text is a snippet from Wiktionary: spacetime