In mathematics, gap theorem may refer to:
The Hadamard gap theorem on lacunary functions The Fabry gap theorem on lacunary functions Pólya's gap theorem on power series The Weierstrass gap theorem in algebraic geometry The gap theorem of Fourier analysis, a statement about the vanishing of discrete Fourier coefficients for functions that are identically zero on an interval shorter than 2π The gap theorem in computational complexity theory Saharon Shelah's Main Gap Theorem which solved Morley's problem in model theory