Torsion

Torsion may refer to:

• In geometry:
  • Torsion of a curve
  • Torsion tensor in differential geometry
  • The closely related concepts of Reidemeister torsion (also called R-torsion, Franz torsion, de Rham torsion) and analytic torsion (also called Ray-Singer torsion)
  • Whitehead torsion
  • Dihedral angle

• In algebra:
  • Torsion (algebra)
  • Tor functor
  • Torsion-free module

• In medicine:
  • Of bones, "torsion fracture" is another term for spiral fracture.
  • Of organs, torsion refers to twisting, in particular twisting that interrupts the blood supply to that organ, e.g. splenic torsion, ovarian torsion, or testicular torsion.
  • Torsion of the digestive tract in some domestic animals:
    • A type of horse colic
    • One complication of bloat (gastric torsion)

• In physics and engineering:
  • Torsion (mechanics)
  • Torsion coefficient
  • Torsion pendulum
  • Torsion spring or -bar

• In science and pseudoscience
  • Torsion balance, a delicate measuring instrument used in scientific research
  • Torsion field (pseudoscience), a field alleged to make faster-than-light communication and paranormal phenomena possible, a theory by Russian scientists
  • The field used in Einstein–Cartan theory and other alternatives to general relativity that involve torsion of spacetime

• In biology:
  • Torsion (gastropod), a developmental feature of all gastropods

• In warfare:
  • Torsion siege engine, a kind of catapult