Supersymmetry of FRW barotropic cosmologies

Barotropic FRW cosmologies are presented from the standpoint of nonrelativistic supersymmetry. First, we reduce the barotropic FRW system of differential equations to simple harmonic oscillator differential equations. Employing the factorization procedure, the solutions of the latter equations are divided into the two classes of bosonic (nonsingular) and fermionic (singular) cosmological solutions. We next introduce a coupling parameter denoted by K between the two classes of solutions and obtain barotropic cosmologies with dissipative features acting on the scale factors and spatial curvature of the universe. The K-extended FRW equations in comoving time are presented in explicit form in the low coupling regime. The standard barotropic FRW cosmologies correspond to the dissipationless limit K =0Comment: 6 page

Supersymmetric Fokker-Planck strict isospectrality

I report a study of the nonstationary one-dimensional Fokker-Planck solutions by means of the strictly isospectral method of supesymmetric quantum mechanics. The main conclusion is that this technique can lead to a space-dependent (modulational) damping of the spatial part of the nonstationary Fokker-Planck solutions, which I call strictly isospectral damping. At the same time, using an additive decomposition of the nonstationary solutions suggested by the strictly isospectral procedure and by an argument of Englefield [J. Stat. Phys. 52, 369 (1988)], they can be normalized and thus turned into physical solutions, i.e., Fokker-Planck probability densities. There might be applications to many physical processes during their transient periodComment: revised version, scheduled for PRE 56 (1 August 1997) as a B

Supersymmetric pairing of kinks for polynomial nonlinearities

We show how one can obtain kink solutions of ordinary differential equations with polynomial nonlinearities by an efficient factorization procedure directly related to the factorization of their nonlinear polynomial part. We focus on reaction-diffusion equations in the travelling frame and damped-anharmonic-oscillator equations. We also report an interesting pairing of the kink solutions, a result obtained by reversing the factorization brackets in the supersymmetric quantum mechanical style. In this way, one gets ordinary differential equations with a different polynomial nonlinearity possessing kink solutions of different width but propagating at the same velocity as the kinks of the original equation. This pairing of kinks could have many applications. We illustrate the mathematical procedure with several important cases, among which the generalized Fisher equation, the FitzHugh-Nagumo equation, and the polymerization fronts of microtubulesComment: 13 pages, 2 figures, revised during the 2nd week of Dec. 200

The new Indies, the desired Indies: Antonio Possevino and the Jesuits between diplomacy and missionarism in northeastern Europe, 1577-1587

This paper discusses the diplomatic career of a Jesuit whose political acumen and militant understanding of mission went to loggerheads with imperial, papal, and even Jesuit interests in northeastern Europe. Antonio Possevino (1533-1611) was a priest, writer, and administrator who served as the superior of the Jesuit mission in Sweden and the pope’s extraordinary legate to Muscovy, the Polish-Lithuanian Commonwealth, and the Holy Roman Empire between 1577 and 1587. Like any high-ranking Jesuit, Possevino had dreams of global evangelization, but the means he envisaged for attaining them were predominantly political and military. During his diplomatic career he became so enmeshed in local politics that he was accused of partiality to the Polish-Lithuanian king, whose envoy he effectively became on several occasions. At the request of the imperial court, who perceived him as hostile to their interests, and despite Possevino’s efforts to prove his impartiality, his superiors dismissed him from his diplomatic activities. Exiled in Italy, far from high-level politics, Possevino remained involved with northeastern Europe, but only behind the scenes or under the cover of a pseudonym. His story illustrates the multiple identities and uneasy but inevitable mixture of politics and religion in early modern Catholic diplomacy. Collective identities and transnational networks in medieval and early modern Europe, 1000-180

Review of Flóra, Á. (2019) The matter of honour: the leading urban elite in sixteenth century Transylvania

Collective identities and transnational networks in medieval and early modern Europe, 1000-180

Benchmarking acid and base dopants with respect to enabling the ice V to XIII and ice VI to XV hydrogen-ordering phase transitions

Doping the hydrogen-disordered phases of ice V, VI and XII with hydrochloric acid (HCl) has led to the discovery of their hydrogen-ordered counterparts ices XIII, XV and XIV. Yet, the mechanistic details of the hydrogen-ordering phase transitions are still not fully understood. This includes in particular the role of the acid dopant and the defect dynamics that it creates within the ices. Here we investigate the effects of several acid and base dopants on the hydrogen ordering of ices V and VI with calorimetry and X-ray diffraction. HCl is found to be most effective for both phases which is attributed to a favourable combination of high solubility and strong acid properties which create mobile H3O+ defects that enable the hydrogen-ordering processes. Hydrofluoric acid (HF) is the second most effective dopant highlighting that the acid strengths of HCl and HF are much more similar in ice than they are in liquid water. Surprisingly, hydrobromic acid doping facilitates hydrogen ordering in ice VI whereas only a very small effect is observed for ice V. Conversely, lithium hydroxide (LiOH) doping achieves a performance comparable to HF-doping in ice V but it is ineffective in the case of ice VI. Sodium hydroxide, potassium hydroxide (as previously shown) and perchloric acid doping are ineffective for both phases. These findings highlight the need for future computational studies but also raise the question why LiOH-doping achieves hydrogen-ordering of ice V whereas potassium hydroxide doping is most effective for the 'ordinary' ice Ih.Comment: 18 pages, 7 figures, 1 tabl

Review of Kálnoky, N. (2020) The Szekler Nation and Medieval Hungary: Politics, Law and Identity on the Frontier

Collective identities and transnational networks in medieval and early modern Europe, 1000-180