Birkhoff's theorem

Birkhoff's theorem may refer to several theorems named for the American mathematician George David Birkhoff:

• Birkhoff's theorem (relativity)
• Birkhoff's theorem (electromagnetism)
• Birkhoff's ergodic theorem

It may also refer to theorems named for his son, Garrett Birkhoff:

• Birkhoff–von Neumann theorem for doubly stochastic matrices
• Birkhoff's HSP theorem, concerning the closure operations of homomorphism, subalgebra and product
• Birkhoff's representation theorem for distributive lattices
• Birkhoff's theorem (equational logic), stating that syntactic and semantic consequence coincide