Lepton pair production by high-energy neutrino in an external electromagnetic field

The process of the lepton pair production by a neutrino propagating in an external electromagnetic field is investigated in the framework of the Standard Model. Relatively simple exact expression for the probability as the single integral is obtained, which is suitable for a quantitative analysis.Comment: 9 pages, LATEX, 2 PS figures, submitted to Modern Physics Letters

Chaplygin ball over a fixed sphere: explicit integration

We consider a nonholonomic system describing a rolling of a dynamically non-symmetric sphere over a fixed sphere without slipping. The system generalizes the classical nonholonomic Chaplygin sphere problem and it is shown to be integrable for one special ratio of radii of the spheres. After a time reparameterization the system becomes a Hamiltonian one and admits a separation of variables and reduction to Abel--Jacobi quadratures. The separating variables that we found appear to be a non-trivial generalization of ellipsoidal (spheroconical) coordinates on the Poisson sphere, which can be useful in other integrable problems. Using the quadratures we also perform an explicit integration of the problem in theta-functions of the new time.Comment: This is an extended version of the paper to be published in Regular and Chaotic Dynamics, Vol. 13 (2008), No. 6. Contains 20 pages and 2 figure

Exchange-assisted tunneling in the classical limit

The exchange interaction and correlations may produce a power-law decay instead of the usual exponential decrease of the wave function under potential barrier. The exchange-assisted tunneling vanishes in the classical limit, however, the dependence on the Planck constant h is different from that for a conventional single-particle tunneling

Explication of Concept THOUGHT in Epic Formulas Olonkho “Ala Bulkun” T. V. Zakharova-Chebiy

A study of epic formulas that explicate variations of the concept THOUGHT in the olonkho text of the narrator T. V. Zakharova-Chebiy “Ala Bulkun”, which refers to the early (pre-revolutionary) records of the Yakut epic, is carried out. The results of a conceptual analysis of variations of the concept THOUGHT, which, according to the author's observations, are formed during the functioning of the lexemes sanaa ‘thought’ (39 formulas) and tolkuy ‘thought, idea, consideration, reflection’ (7 formulas), taking into account the general context of epic formulas are presented in the article. It has been established that the concept THOUGHT, as a prototype that reveals the greatest number of characteristics, underlies the formation of the following concept-variations derived from it: ANGRY THOUGHTS, BOLD THOUGHTS, REFLECTION, INTENTION, LIGHTNESS, BAD THOUGHTS, HEAVY THOUGHTS, HURRY THOUGHTS and THOUGHTS ABOUT LOVE. It has been established that conceptual information can also come from the general context of an epic formula without a representative lexeme. It was revealed that the studied concepts carry an axiological load and serve to reveal the images of epic characters. According to the author, the estimated value of the concepts under consideration, in addition to the cognitive function itself, is also one of the factors contributing to the stability of the epic formula

Epic Formulas with a Matrix Construction: from Stability in Structure to Reference in Consciousness (Image of a Hero in the Yakut Olonkho)

The complex processes involved in the generation of the image of the hero by the narrator and the perception of this image by the epic audience are studied. A comprehensive analysis of epic formulas with a matrix construction is carried out in order to identify their reference models. The novelty of the work lies in the fact that for the first time the problems of human speech-thinking activity on the basis of the epic formulas of the Yakut olonkho are considered. As a result of the research, the author comes to the conclusion that when revealing the image of the hero, the narrator uses the parallels as a referent: property of the material / property of the image. It is noted that, in turn, the recipients decipher these constructions thanks to the background knowledge about the referent, in particular, about the property of the described material, which is mentally brought under the image of a hero. According to the author, the very structure of the organization of matrix structures does not allow the olonkhosut to completely replace the components that form the referent. Moreover, it is stated that the structure of the analyzed constructions ignores even gender differences in describing the image of heroic women. It is pointed out that the described processes, when the narrator recites certain analyzed epic formulas, occur in a very short time