Schwarzschild wormholes

A wormhole is a solution of the Einstein field equations having a non-trivial structure linking separate points in spacetime, much like a tunnel with two ends, each at separate points in spacetime. Such connections are consistent with the general theory of relativity, yet their existence remains hypothetical.

A wormhole may connect extremely long distances such as a billion light years or more; short distances such as a few meters; different universes; and/or different points in time. This is proposed in Albert Einstein's special theory of relativity, where the combination of space and time into a single spacetime continuum could theoretically allow one to traverse both space and time using a wormhole with the correct conditions.

In 1921, Hermann Weyl proposed a wormhole theory of matter in connection with mass analysis of electromagnetic field energy; however, he did not use the term "wormhole" (he spoke of "one-dimensional tubes" instead).

American theoretical physicist John Archibald Wheeler (inspired by Weyl's work) coined the term "wormhole" in a 1957 paper co-authored by Charles Misner:

This analysis forces one to consider situations... where there is a net flux of lines of force, through what topologists would call "a handle" of the multiply-connected space, and what physicists might perhaps be excused for more vividly terming a "wormhole".

Wormholes have been defined both geometrically and topologically,

An intra-universe wormhole (a wormhole between two points in the same universe) is a compact region of spacetime whose boundary is topologically trivial, but whose interior is not simply connected. Formalizing this idea leads to definitions such as the following, taken from Matt Visser's Lorentzian Wormholes (1996).

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