A new touch temperature of the event horizon and Rindler horizon in the Kinnersley spacetime

The Kinnersley spacetime not only describes a non-spherical symmetric, non-stationary and accelerating black hole, but also can be used to explore the characteristics of collision of two black holes because it has two horizons: the Rindler horizon and the event horizon. Previous research shows Rindler horizon and the event horizon cannot touch due to violation of the third law of thermodynamics. By solving a fermion dynamical equation including the Lorentz dispersion relation, we obtain a modified radiation temperature at the event horizon of the black hole, as well as the colliding temperature at the touch point of Rindler horizon and the event horizon. We find the temperature at the touch point is not equal to zero if $${\dot{r}}_H\ne 0$$ r ˙ H ≠ 0 . This result indicates that the event horizon and Rindler horizon can collide without violation of the third law of thermodynamics when Lorentz dispersion relation is considered.

Some Implications of a Scale Invariant Model of Statistical Mechanics to Boltzmann versus Shannon Entropy in Thermodynamics and Information Theory

A scale invariant model of statistical mechanics is applied for a comparative study of Boltzmann’s entropy in thermodynamics versus Shannon’s entropy in information theory. The implications of the model to the objective versus subjective aspects of entropy as well as Nernst-Planck statement of the third law of thermodynamics are also discussed

Nernst equation applied to electrochemical systems and centenary of his Nobel Prize in chemistry

Walther Hermann Nernst received the Nobel Prize in Chemistry in 1920 for the formulation of the third law of thermodynamics, thus celebrating a century in this 2020 year. His work helped the establishment of modern physical chemistry, since he researched into fields, such as thermodynamics and electrochemistry, in which the Nernst equation is included. This paper reports on several experiments that used a Daniell galvanic cell working in different electrolyte concentrations for comparing results with the theoretical values calculated by the Nernst equation. The concentration and activity coefficients values employed for zinc sulfate and copper electrolytes showed activity can replaces concentrations in thermodynamic functions, and the results are entirely consistent with experimental data. The experimental electromotive force from standard Daniell cell, for ZnSO4 and CuSO4, with unitary activity and in different concentrations at room temperature is in agreement with those from theoretical calculations. Cu2+ ion concentrations and temperature were simultaneously varied; however, the cell potential cannot be included in calculations of Nernst equation for different temperatures than 25 °C because the standard potential value was set at 25 °C. The cell potential decreases drastically when the Cu2+ concentration was reduced and the temperature was above 80 oC.

A possible thermodynamic origin of the spacetime minimum length

In this paper, by applying the generalized uncertainty principle (GUP) at the final stage of black hole evaporation, we have proposed a thermodynamic explanation for the minimal scale of quantum gravity, i.e. it may stem from the basic requirements of the third law of thermodynamics for quantum gravitation system. At the same time, we have interestingly found that the third law of black hole thermodynamics acts as a supervisor in quantum gravity spacetime to ensure the causality of the spacetime as that does in classical gravity.

Observation of an apparent first-order glass transition in ultrafragile Pt–Cu–P bulk metallic glasses

An experimental study of the configurational thermodynamics for a series of near-eutectic Pt80-xCuxP20 bulk metallic glass-forming alloys is reported where 14 < x < 27. The undercooled liquid alloys exhibit very high fragility that increases as x decreases, resulting in an increasingly sharp glass transition. With decreasing x, the extrapolated Kauzmann temperature of the liquid, TK, becomes indistinguishable from the conventionally defined glass transition temperature, Tg. For x < 17, the observed liquid configurational enthalpy vs. T displays a marked discontinuous drop or latent heat at a well-defined freezing temperature, Tgm. The entropy drop for this first-order liquid/glass transition is approximately two-thirds of the entropy of fusion of the crystallized eutectic alloy. Below Tgm, the configurational entropy of the frozen glass continues to fall rapidly, approaching that of the crystallized eutectic solid in the low T limit. The so-called Kauzmann paradox, with negative liquid entropy (vs. the crystalline state), is averted and the liquid configurational entropy appears to comply with the third law of thermodynamics. Despite their ultrafragile character, the liquids at x = 14 and 16 are bulk glass formers, yielding fully glassy rods up to 2- and 3-mm diameter on water quenching in thin-wall silica tubes. The low Cu content alloys are definitive examples of glasses that exhibit first-order melting.

The Nernst Postulate: The Third Law of Thermodynamics

The Nernst postulate, or Third Law of Thermodynamics, is derived from quantum statistical mechanics. It states, ‘The entropy of a thermodynamic system goes to a constant as the temperature goes to zero.’ The main consequences are that specific heat and compressibility goes to zero as temperature goes to zero. Both are demonstrated. It is shown that, both with and without the Nernst postulate, zero temperature is not experimentally attainable. Gases are usually well behaved in this respect, but we all know from experience that molecules of H2O can clump together, form drops, and rain on us.