Spontaneous Symmetry Breaking, Off-diagonal Long-range Order, and Nucleation of Quantum State
نویسنده
چکیده
Spontaneous symmetry breaking is determined by quantum mechanical measurement, and is classified to two types according to whether Hamiltonian commutes the relevant observable, the average of which is the order parameter. A supplement regarding phases is given to the expansion postulate and validate ensemble description of many-particle systems. Interference between many-particle states, macroscopic wavefunction, and off-diagonal long-range order present when there is a so-called nucleation of quantum state, which is proposed to be the origin of spontaneous gauge symmetry breaking. PACS Numbers: 05.30.-d, 03.65.Bz, 03.75.-b, 11.30.Qc Keywords; spontaneous symmetry breaking, macroscopic wavefunction, off-diagonal long-range order, nucleation of quantum state
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