Inversion or inversions may refer to:

Arts

* , a French gay magazine (1924/1925) * ''Inversion'' (artwork), a 2005 temporary sculpture in Houston, Texas * Inversion (music), a term with various meanings in music theory and musical set theory * ''Inversions'' (novel) by Iain M. Banks * ''Inversion'' (video game), a 2012 third person shooter for Xbox 360, PlayStation 3, and PC * ''Inversions'' (EP), the 2014 extended play album by American rock music ensemble The Colourist * ''Inversions'' (album), a 2019 album by Belinda O'Hooley * ''Inversion'' (film), a 2016 Iranian film

Linguistics and language

* Inversion (linguistics), grammatical constructions where two expressions switch their order of appearance *

Inversion (prosody) In English poetry substitution, also known as inversion, is the use of an alien metric foot in a line of otherwise regular metrical pattern. For instance in an iambic line of "da DUM", a trochaic substitution would introduce a foot of "DUM&n ...

, the reversal of the order of a foot's elements in poetry * Anastrophe, a figure of speech also known as an ''inversion''

Mathematics and logic

Involution (mathematics) In mathematics, an involution, involutory function, or self-inverse function is a function that is its own inverse, : for all in the domain of . Equivalently, applying twice produces the original value. General properties Any involution ...

, a function that is its own inverse (when applied twice, the starting value is obtained) *

Inversion (discrete mathematics) In computer science and discrete mathematics, an inversion in a sequence is a pair of elements that are out of their natural order. Definitions Inversion Let \pi be a permutation. There is an inversion of \pi between i and j if i \pi(j). ...

, any item that is out of order in a sequence *

Inverse element In mathematics, the concept of an inverse element generalises the concepts of opposite () and reciprocal () of numbers. Given an operation denoted here , and an identity element denoted , if , one says that is a left inverse of , and that ...

* Inversive geometry#Circle inversion, a transformation of the Euclidean plane that maps generalized circles to generalized circles * Inversion in a point, or point reflection, a kind of isometric (distance-preserving) transformation in a Euclidean space * Inversion transformation, a conformal transformation (one which preserves angles of intersection) * Method of inversion, the image of a harmonic function in a sphere (or plane); see

Method of image charges The method of image charges (also known as the method of images and method of mirror charges) is a basic problem-solving tool in electrostatics. The name originates from the replacement of certain elements in the original layout with imaginary c ...

Multiplicative inverse In mathematics, a multiplicative inverse or reciprocal for a number ''x'', denoted by 1/''x'' or ''x''−1, is a number which when multiplied by ''x'' yields the multiplicative identity, 1. The multiplicative inverse of a fraction ''a''/''b ...

, the reciprocal of a number (or any other type of element for which a multiplication function is defined) *

Matrix inversion In linear algebra, an -by- square matrix is called invertible (also nonsingular or nondegenerate), if there exists an -by- square matrix such that :\mathbf = \mathbf = \mathbf_n \ where denotes the -by- identity matrix and the multiplicat ...

, an operation on a matrix that results in its multiplicative inverse * Model inversion *

Set inversion In mathematics, set inversion is the problem of characterizing the preimage ''X'' of a set ''Y'' by a function ''f'', i.e., ''X'' = ''f'' −1(''Y'' ) = . It can also be viewed as the problem of describing the solution set ...

Natural sciences

Biology and medicine

* Inversion (evolutionary biology), a hypothesis about the evolution of the dorsoventral axis in animals * Inversion (kinesiology), movement of the sole towards the median plane * Chromosomal inversion, where a segment of a chromosome is reversed end-to-end *

Inversion therapy Inversion therapy, or simply inversion, is the process of seeking therapeutic benefits from hanging by the legs, ankles, or feet in an inverted angle or entirely upside down. It is a form of spinal traction. Spinal Traction can be useful for eff ...

, the practice of hanging upside down (heart higher than head) for supposed health benefits

Geology

* Inversion (geology), the relative uplift of a previously basinal area resulting from local shortening, in structural geology *

Relief inversion Inverted relief, inverted topography, or topographic inversion refers to landscape features that have reversed their elevation relative to other features. It most often occurs when low areas of a landscape become filled with lava or sediment th ...

, when a previous depression becomes a landform that stands out from its surroundings *

Seismic inversion In geophysics (primarily in oil-and-gas exploration/development), seismic inversion is the process of transforming seismic reflection data into a quantitative rock-property description of a reservoir. Seismic inversion may be pre- or post-stack, ...

, transforming seismic reflection data into a quantitative rock-property description of a geological formation

Physics and chemistry

Island of inversion An island of inversion is a region of the chart of nuclides that contains isotopes with a non-standard ordering of single particle levels in the nuclear shell model. Such an area was first described in 1975 by French physicists carrying out spec ...

, a group of elements with abnormal nuclear shell structure * Nitrogen inversion, a chemical process in which a trigonal nitrogen-containing structure turns inside-out * Population inversion, in statistical mechanics, when a system exists in state with more members in an excited state than in lower-energy states * Pyramidal inversion, a chemical process in which a trigonal structure turns inside-out *

Inverted sugar syrup Inverted sugar syrup, also called invert syrup, invert sugar, simple syrup, sugar syrup, sugar water, bar syrup, syrup USP, or sucrose inversion, is a syrup mixture of the monosaccharides glucose and fructose, that is made by hydrolytic ...

, a chemical reaction converting sucrose into glucose and fructose

Other uses in the natural sciences

Inverse problem An inverse problem in science is the process of calculating from a set of observations the causal factors that produced them: for example, calculating an image in X-ray computed tomography, source reconstruction in acoustics, or calculating th ...

, the process of calculating from a set of observations the causal factors that produced them *

Inversion (meteorology) In meteorology, an inversion is a deviation from the normal change of an atmospheric property with altitude. It almost always refers to an inversion of the air temperature lapse rate, in which case it is called a temperature inversion. ...

, air temperature increasing with height

Other uses

Priority inversion In computer science, priority inversion is a scenario in scheduling in which a high priority task is indirectly superseded by a lower priority task effectively inverting the assigned priorities of the tasks. This violates the priority model that h ...

, the condition of a low-priority task holding a shared resource that a high-priority task needs *

Inversion in postcolonial theory The concept of inversion in postcolonial theory and subaltern studies refers to a discursive strategy which opposes or resists a dominant discourse by turning around its categories and re-enacting an asymmetrical relation with the terms the other ...

, a discursive strategy/gesture in cultural and subaltern studies *

Roller coaster inversion A roller coaster inversion is a roller coaster element in which the track turns riders upside-down and then returns them to an upright position. Early forms of inversions were circular in nature and date back to 1848 on the Centrifugal railway i ...

, which turns riders upside-down *

Tax inversion A tax inversion or corporate tax inversion is a form of tax avoidance where a corporation restructures so that the current parent is replaced by a foreign parent, and the original parent company becomes a subsidiary of the foreign parent, thus mov ...

, a form of tax avoidance by moving corporate ownership to low-tax nations