Quantum Mechanics and Quantum Field Theory

In physics, the no-cloning theorem states that it is impossible to create an independent and identical copy of an arbitrary unknown quantum state, a statement which has profound implications in the field of quantum computing among others.

The spin-statistics theorem proves that the observed relationship between the intrinsic spin of a particle (angular momentum not due to the orbital motion) and the quantum particle statistics of collections of such particles is a consequence of the mathematics of quantum mechanics.

CPT is the only combination of C, P, and T that is observed to be an exact symmetry of nature at the fundamental level. The CPT theorem says that CPT symmetry holds for all physical phenomena, or more precisely, that any Lorentz invariant local quantum field theory with a Hermitian Hamiltonian must have CPT symmetry.

In condensed matter physics, Bloch's theorem states that solutions to the Schrödinger equation in a periodic potential can be expressed as plane waves modulated by periodic functions.

related results in physics, all of which determine that quantum mechanics is incompatible with local hidden-variable theories

In quantum mechanics, the Kochen-Specker (KS) theorem, also known

value. It is most apparent in the Heisenberg picture of quantum mechanics, where it amounts to just the expectation value

1931, is a cornerstone of the mathematical formulation of quantum mechanics. The theorem specifies how physical symmetries

physicist Gian Carlo Wick. It is used extensively in quantum field theory to reduce arbitrary products of creation and

In theoretical physics, the Coleman-Mandula theorem is a no-go theorem

The adiabatic theorem is a concept in quantum mechanics. Its original form, due to Max Born and Vladimir

In quantum mechanics, the Hellmann-Feynman theorem relates the derivative

the mathematical physics of an interacting, relativistic, quantum field theory, Rudolf Haag developed an argument against the

Reeh-Schlieder theorem is a result in relativistic local quantum field theory published by Helmut Reeh and Siegfried Schlieder

In quantum mechanics, Kramers' theorem or Kramers' degeneracy theorem

theorem is a theorem of representation theory and quantum mechanics. It states that matrix elements of spherical

(j = 2) cannot be a composite particle in a relativistic quantum field theory.

In quantum field theory and statistical field theory, Elitzur's theorem

shows that the rule one uses to calculate probabilities in quantum physics, the Born rule, can be derived from the usual

of the past, then, under specific assumptions drawn from quantum mechanics and relativity, so must some elementary particles.

In quantum information and computation, the Solovay-Kitaev

In quantum field theory and statistical mechanics, the Hohenberg-Mermin-Wagner