scholarly journals The Law of Entropy Increase and the Meissner Effect

Entropy ◽  
2022 ◽  
Vol 24 (1) ◽  
pp. 83
Author(s):  
Alexey Nikulov

The law of entropy increase postulates the existence of irreversible processes in physics: the total entropy of an isolated system can increase, but cannot decrease. The annihilation of an electric current in normal metal with the generation of Joule heat because of a non-zero resistance is a well-known example of an irreversible process. The persistent current, an undamped electric current observed in a superconductor, annihilates after the transition into the normal state. Therefore, this transition was considered as an irreversible thermodynamic process before 1933. However, if this transition is irreversible, then the Meissner effect discovered in 1933 is experimental evidence of a process reverse to the irreversible process. Belief in the law of entropy increase forced physicists to change their understanding of the superconducting transition, which is considered a phase transition after 1933. This change has resulted to the internal inconsistency of the conventional theory of superconductivity, which is created within the framework of reversible thermodynamics, but predicts Joule heating. The persistent current annihilates after the transition into the normal state with the generation of Joule heat and reappears during the return to the superconducting state according to this theory and contrary to the law of entropy increase. The success of the conventional theory of superconductivity forces us to consider the validity of belief in the law of entropy increase.

2018 ◽  
Vol 32 (13) ◽  
pp. 1850158 ◽  
Author(s):  
J. E. Hirsch

Since the discovery of the Meissner effect, the superconductor to normal (S–N) phase transition in the presence of a magnetic field is understood to be a first-order phase transformation that is reversible under ideal conditions and obeys the laws of thermodynamics. The reverse (N–S) transition is the Meissner effect. This implies in particular that the kinetic energy of the supercurrent is not dissipated as Joule heat in the process where the superconductor becomes normal and the supercurrent stops. In this paper, we analyze the entropy generation and the momentum transfer between the supercurrent and the body in the S–N transition and the N–S transition as described by the conventional theory of superconductivity. We find that it is not possible to explain the transition in a way that is consistent with the laws of thermodynamics unless the momentum transfer between the supercurrent and the body occurs with zero entropy generation, for which the conventional theory of superconductivity provides no mechanism. Instead, we point out that the alternative theory of hole superconductivity does not encounter such difficulties.


2016 ◽  
Vol 845 ◽  
pp. 146-149
Author(s):  
Dmitriy S. Kuchin ◽  
Victor V. Koledov ◽  
Pavel V. Bogun ◽  
Peter V. Lega ◽  
Vedamanickam Sampath ◽  
...  

A new technique for the production of nanograined alloys from rapidly quenched amorphous ribbons by serial electric pulses has been proposed recently [1]. The present work involves a theoretical study of electric current flow in a nonhomogeneous Ti2NiCu alloy consisting of an amorphous matrix with a crystalline phase of spherical morphology embedded in it. The electric current density distribution was calculated in the vicinity of a spherical nucleus, which has an electrical resistance that is only 0.4 times that of the amorphous matrix. The calculation of Joule heat density was done in the nucleus and in the amorphous volume surrounding it. It was shown that during the current pulse the Joule heat evolution in nucleus exceeds one in equatorial region in matrix, but less than near the poles. The dependence of relative resistivity of nonhomogeneous amorphous-crystalline alloy on volume fraction of spherical crystalline nuclei was calculated


2019 ◽  
Vol 4 (12) ◽  

"The agent Na + acts constantly on the circulatory rotation of the neurons, which accentuates the operational deficiency of the cellular rhythm in normal state, the agent Ca acts on the bone system and indirectly on the cardiac rhythm. This relativity provokes the law of body weight with respect to atmospheric deficiency."


2021 ◽  
Author(s):  
Yannan Yang

Abstract In this article, a loop that is partly electrostatic shielded is analyzed. It is found that the line integral of electrostatic field around this loop is not zero. This is against the theorem that the line integral of electrostatic field around any closed loop is zero and the curl of electrostatic field is zero. When the loop is made of conductor wire, there is no electric current flowing around the loop although the line integral of electric field is not zero. A loop current driven by electrostatic field will break the law of energy conservation, so it is expected and reasonable that we cannot observe a current in the loop.


2019 ◽  
Vol 298 ◽  
pp. 00145
Author(s):  
Vladimir Fedyaev ◽  
Petr Osipov ◽  
Alexey Belyaev ◽  
Liliya Sirotkina

One of the effective methods of surfacing protective coatings on large areas, as well as the formation of permanent joints is the method of immersion (dipping) of parts into the melt. In order to increase the productivity of this method, the quality of surfacing is proposed to heat the work surfaces of the parts with an electroslag method. The rational regimes for its realization are determined by calculation. A mathematical model is proposed for heating the contacting layers of a solid body, slag and melt, taking into account the Joule heat released during the passage of an electric current. The corresponding problem is solved numerically with the help of the method of finite differences. The results are discussed, practical recommendations are presented.


2012 ◽  
Vol 34 (1) ◽  
pp. 83-94 ◽  
Author(s):  
Pier A Mello ◽  
Rosalío F Rodríguez
Keyword(s):  

The experiments to be described in this paper arose from a suggestion by M. von Laue that it would be of interest to examine more closely the behaviour of simply and multiply connected supraconducting bodies in an external magnetic field. If a closed circuit be taken wholly within a supraconducting body, sufficiently far from the surface, the magnetic flux through the circuit should be constant as long as no part of the body is subjected to a magnetic field greater than the critical field strength. For a simply connected body, if the spontaneous ejection of flux on cooling through the transition point, the so-called Meissner effect, is complete, the constant flux through any circuit should be zero. For a multiply connected body, it should be equal to the value immediately after the body became supraconducting. Only in the case of a multiply connected body, that is, a closed circuit, can there be a resultant current through any cross-section in the steady state. This may be taken as a definition of the current I in the circuit, the so-called persistent current. Let L be the self-inductance of the circuit, calculated for the supraconducting state on the assumption that the current flows entirely in a layer very close to the surface. Let ϕ be the calculated magnetic flux through the circuit due to external magnetic field, allowing for the distortion of the field by the presence of supraconducting material. Then, if it can be assumed that the maintenance of the constant flux through the closed circuit is due to a persistent current in the above sense, the law of constant flux can be written in the form LI + ϕ = ϕ 0 . (1)


2016 ◽  
Vol 54 (6) ◽  
pp. 348-350 ◽  
Author(s):  
William Dittrich ◽  
Robert Drosd ◽  
Leonid Minkin ◽  
Alexander S. Shapovalov

1997 ◽  
Vol 89 (3-4) ◽  
pp. 801-816 ◽  
Author(s):  
Toshio Niwa

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