(political science) The theory that the far left and the far right, rather than being at opposite ends of a political continuum, in fact closely resemble one another.

A theorem of representation theory and quantum mechanics, stating that matrix elements of spherical tensor operators on the basis of angular momentum eigenstates can be expressed as the product of two factors, one of which is independent of angular momentum orientation, and the other a Clebsch-Gordan coefficient.

(mathematical logic) A theorem stating that, if a countable first-order theory has an infinite model, then for every infinite cardinal number κ it has a model of size κ. The result implies that first-order theories are unable to control the cardinality of their infinite models, and that no first-order theory with an infinite model can have a unique model up to isomorphism.

(graph theory) The theorem stating that every cubic bridgeless graph contains a perfect matching.

(mathematics) An important structural theorem in the theory of Banach spaces, essentially stating that every sufficiently high-dimensional normed vector space will have low-dimensional subspaces that are approximately Euclidean.

(statistics) A theorem relating to the distribution of the likelihood ratio.

(US) A person who believes that religion should play a role in forming public policy.

plural of theoconservative

(linguistics) A linguistic model proposing that the observed forms of language arise from the interaction between conflicting constraints.

A theorem stating that two connected graphs are isomorphic if and only if their line graphs are isomorphic, with a single exception: K₃, the complete graph on three vertices, and the complete bipartite graph K_(1,3), which are not isomorphic but both have K₃ as their line graph.