The Law of Entropy Increase and the Meissner Effect

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.

The Concept of Entropy and Its Application in Thermal Engineering

Today, 156 years after the invention of entropy by Clausius, there remains disagreement among the scientific community on what entropy and the phenomenon of entropy increase mean [...]

Electric Vehicles That Extract Heat from the Air Without Charging: Entropy Law Does Not Prohibit This

Electromobiles protect the biosphere in places of human residence. Globally, they destroy it, as the electrical energy they consumed is extracted using "dirty" energy carriers. This article suggests learning the electromobiles to generate electrical energy in eco-friendly way, extracting heat from the air. Specifically, we suggest to equip the electromobiles with the Or lov and etc. installation, which schematically is a converging tube where the air flow is by itself accelerated and, according to the Bernoulli equation, is cooled; and its narrow end contains the electrical energy generating turbine. The problem is that the Orlovand etc. installation is prohibited by the entropy increase law due to the flow entropy decrease during its operation. However, it is important that actually in this case the Clausius entropy, i.e. thermal entropy, decreases. The thermal and total entropy increase laws are different laws that separately require verification. Planck, Fermi et al. indicatedthe cases of total conversion of heat into other forms of energy accompanied by thermal en- tropy decrease. These cases, proving invalidity of the thermal entropy increase law, admit transition to electromobiles with air heat trac- tion. As well as transition of water transport to ship's electric engines with water heat traction.

Exponential Negation of a Probability Distribution

Negation operation is important in intelligent information processing. Different with existing arithmetic negation, an exponential negation is presented in this paper. The new negation can be seen as a kind of geometry negation. Some basic properties of the proposed negation are investigated, we find that the fix point is the uniform probability distribution. The proposed exponential negation is an entropy increase operation and all the probability distributions will converge to the uniform distribution after multiple negation iterations. The convergence speed of the proposed negation is also faster than the existed negation. The number of iterations of convergence is inversely proportional to the number of elements in the distribution. Some numerical examples are used to illustrate the efficiency of the proposed negation.

Causality Is an Effect, II

Causality follows the thermodynamic arrow of time, where the latter is defined by the direction of entropy increase. After a brief review of an earlier version of this article, rooted in classical mechanics, we give a quantum generalization of the results. The quantum proofs are limited to a gas of Gaussian wave packets.

Mixing indistinguishable systems leads to a quantum Gibbs paradox

The classical Gibbs paradox concerns the entropy change upon mixing two gases. Whether an observer assigns an entropy increase to the process depends on their ability to distinguish the gases. A resolution is that an “ignorant” observer, who cannot distinguish the gases, has no way of extracting work by mixing them. Moving the thought experiment into the quantum realm, we reveal new and surprising behaviour: the ignorant observer can extract work from mixing different gases, even if the gases cannot be directly distinguished. Moreover, in the macroscopic limit, the quantum case diverges from the classical ideal gas: as much work can be extracted as if the gases were fully distinguishable. We show that the ignorant observer assigns more microstates to the system than found by naive counting in semiclassical statistical mechanics. This demonstrates the importance of accounting for the level of knowledge of an observer, and its implications for genuinely quantum modifications to thermodynamics.

Engines and Refrigerators

The laws of energy conservation and entropy increase put limits on the efficiency of any heat engine and any refrigeration device working over a given temperature range. The limits are independent of the details of how these machines operate, so this chapter first explains them by considering only energy and entropy flows. The detailed mechanisms are still interesting, however, so the chapter ends with descriptions of a variety of engine and refrigeration mechanisms, including methods of reaching temperatures near absolute zero.

Interactions and Implications

Although the law of entropy increase governs the direction in which things change, we don’t observe entropy directly. Instead we observe three quantities—temperature, pressure, and chemical potential—that tell us how the entropy of a system changes as it interacts in three different ways with its surroundings. This chapter shows how these three quantities are mathematically related to a system’s entropy, energy, volume, and number of particles. These relations complete the foundation of macroscopic thermodynamics. Moreover, for the three model systems whose entropies are calculated explicitly in the previous chapter, these relations lead to detailed testable predictions of thermal behavior.