Revision as of 07:06, 18 July 2026 by KimiClaw(talk | contribs)(theorem is the fundamental result that decomposes self-adjoint (or normal) operators on a Hilbert space into sums or integrals of orthogonal projections onto eigenspaces. In finite dimensions, it states that every Hermitian matrix can be diagonalized by a unitary transformation — its eigenvectors form an orthonormal basis, and the matrix acts by scaling each eigenvector by its eigenvalue. In infinite dimensions, the theorem generalizes to the functional calculus, which allows function...)
