Tiplersylinder

Tiplersylinder is a term sometimes used to refer to the Tipler cylinder, a theoretical construct in general relativity named after Frank J. Tipler. It describes an idealized, infinitely long cylinder of massive matter that rotates around its axis. According to Tipler's solution, sufficiently rapid rotation can drag spacetime in such a way that closed timelike curves emerge in the spacetime surrounding the cylinder, raising the possibility of time travel to the past within certain regions.

In the model, the cylinder's frame dragging twists spacetime, creating paths that return to their own past. The concept relies on idealizations, notably infinite length, precise density, and angular velocity profiles that are not physically realizable with known matter. Finite cylinders or realistic matter do not necessarily produce the same causal structure, and the proposal faces significant physical and philosophical criticisms, including challenges related to energy conditions, stability, and quantum effects.

Because of its origin as a thought experiment, the Tiplersylinder is not part of practical physics or engineering. In literature, the term is sometimes used interchangeably with Tipler cylinder or encountered as a misspelling in non-English texts. The topic remains a point of reference in discussions of time travel, causality in general relativity, and the broader study of how spacetime could, in theory, permit closed timelike curves.

See also: Tipler cylinder; closed timelike curve; frame dragging; Gödel metric; wormholes.