Torsion

Torsion may refer to:

Science

• Torsion (mechanics), the twisting of an object due to an applied torque
• Torsion of spacetime, the field used in Einstein–Cartan theory and
  • Alternatives to general relativity
• Torsion angle, in chemistry

Biology and medicine

• Torsion fracture or spiral fracture, a bone fracture when torque is applied
• Organ torsion, twisting that interrupts the blood supply to that organ:
  • Splenic torsion, causing splenic infarction
  • Ovarian torsion
  • Testicular torsion
• Penile torsion, a congenital condition
• Torsion of the digestive tract in some domestic animals:
  • Torsion, a type of horse colic
  • Gastric torsion, or gastric dilatation volvulus
• Torsion (gastropod), a developmental feature of all gastropods

Mathematics

• Torsion of a curve
• Torsion tensor, in differential geometry
• Torsion (algebra), in ring theory
• Torsion group, in group theory and arithmetic geometry
• Tor functor, the derived functors of the tensor product of modules over a ring
• Torsion-free module, in algebra
• Analytic torsion (Reidemeister torsion, R-torsion, Franz torsion, de Rham torsion, Ray-Singer torsion), a topological invariant of manifolds
• Whitehead torsion, in geometric topology

Other uses

• Torsion field (pseudoscience), a field alleged to make faster-than-light communication and paranormal phenomena possible