Grelling-Nelson paradox

plural of Weyl group

(mathematics) A subgroup of the isometry group of a root system, generated by reflections through the hyperplanes orthogonal to the roots.

(electronics, quantum mechanics) A massless quasiparticle and fermion, which carries electric charge, and cannot move backwards, that may exist in Weyl semimetals, where an electron can be split into two Weyl fermions which move in opposite directions, which can form an electron by combining two Weyl fermions.

plural of Weyl fermion

(algebra) The ring of differential operators with polynomial coefficients (in one variable), namely expressions of the form f_m(X)∂_Xᵐ+f_m-1(X)∂_Xᵐ⁻¹+⋯+f_1(X)∂_X+f_0(X).

plural of Weyl algebra

plural of Weyl tensor

(differential geometry) A measure of the curvature of spacetime (or, more generally, a pseudo-Riemannian manifold), differing from the Riemann tensor in that it does not convey information on how the volume of the body changes, but only how its shape is distorted by the tidal force.