Energy of magnetic moment of superconducting current in magnetic field

• Quantization effects observed in superconducting loops are considered.
• The energy of magnetic moment in magnetic field can not be deduced from Hamiltonian.
• This energy is deduced from a history of the current state in the classical case.
• It can not be deduced directly in the quantum case.
• Taking this energy into account demolishes agreement between theory and experiment.

The energy of magnetic moment of the persistent current circulating in superconducting loop in an externally produced magnetic field is not taken into account in the theory of quantization effects because of identification of the Hamiltonian with the energy. This identification misleads if, in accordance with the conservation law, the energy of a state is the energy expended for its creation. The energy of magnetic moment is deduced from a creation history of the current state in magnetic field both in the classical and quantum case. But taking this energy into account demolishes the agreement between theory and experiment. Impartial consideration of this problem discovers the contradiction both in theory and experiment.