The transition from the superconducting to the normal state in a magnetic field was considered as a irreversible thermodynamic process before 1933 because of Joule heating. But all physicists became to consider this transition as reversible after 1933 because of the obvious contradiction of the Meissner effect with the second law of thermodynamics if this transition is considered as a irreversible process. In order to avoid the contradiction with the second law of thermodynamics, physicists postulated in the thirties of the last century that the surface screening current is damped without the generation of Joule heat. The superconducting transition is considered as the phase transition since that time and the conventional theory of superconductivity was created in the framework of the equilibrium thermodynamics. The inconsistency of the conventional theory of superconductivity, created in the framework of the equilibrium thermodynamics, with Joule heating, on which Jorge Hirsch draws reader’s attention, is a consequence of this history.

1933 年以前，由于焦耳热，磁场中从超导到常态的转变被认为是不可逆的热力学过程。但所有物理学家在 1933 年之后开始认为这种转变是可逆的，因为如果这种转变被认为是一个不可逆的过程，那么迈斯纳效应与热力学第二定律的明显矛盾。为了避免与热力学第二定律的矛盾，上世纪三十年代，物理学家假设表面屏蔽电流衰减而不产生焦耳热。超导转变被认为是相变，因为那时超导的常规理论是在平衡热力学的框架内创建的。