Haisee provosoidulta : aineiston arvioinnin ongelmia Dmitri Tsvetkovin vatjan sanaston valossa

Summary: Suspicions of provocation: problems of data assesmemt in the light of Dmitri Tsvetkov's Votic dictionary

Kurzrezensionen

Kirjallisuusarvostelu

Uma análise retórica da Fuga Opus 87 nº 4 de Dmitri Shostakovich

O presente trabalho investiga a retórica da Fuga opus 87 n° 4 de Dmitri Shostakovich. Para atingir tal objetivo, foram utilizados os trabalhos de Lester (1986, 2001), Harrison (1990) e Roberts (2004). Neste último, estão os princípios metodológicos utilizados para a realização desta pesquisa, os quais consistem, basicamente, no reconhecimento dos elementos identificadores [notable properties], termo utilizado por Roberts para denominar propriedades distintas de uma fuga. Roberts (2004) aplicou seu método para reconhecer a natureza, retórica ou literal de quatro fugas de Bach para órgão (BWV 533, 545, 547 e 578). Na fuga dupla n° 4, em Mi menor, de Shostakovich foram encontrados cinco elementos identificadores: graus da escala em suspensão, ambigüidade tonal/modal, relação entre Integrantes, presença do terceiro contra-sujeito para um dos sujeitos e seções paralelas intensificadas. No discurso, a presença e inter-relações mútuas dos elementos identificadores estabelecem conflitos, os quais são resolvidos revelando a natureza retórica da composição.

Dmitri : a romance of old Russia /

Mode of access: Internet.

Zapiski Dmitrīi͡a︡ Ivanovicha Sverbeeva, 1799-1826.

Photocopy :

Dmitri; a grand story of Russia.

Mode of access: Internet.

Sbornik stateĭ v chestʹ Dmitrīi︠a︡ Aleksandrovicha Korsakova : po povodu sorokali︠e︡tīi︠a︡ ego uchenoĭ i pi︠a︡tidesi︠a︡tili︠e︡tīi︠a︡ ucheno-literaturnoĭ di︠e︡i︠a︡telʹnosti : istorīi︠a︡, istorīi︠a︡ literatury, arkheologīi︠a︡, i︠a︡zykovi︠e︡di︠e︡nīe filosofīi︠a︡, pedagogike = Mélanges Korsakoff : recueil de travaux, offert à M-r Dmitry Korsakoff, d-r et prof. émer. de l'Université de Kazan, à l'occasion du XL anniversaire de son professorat et de L ans d'activité comme savant et écrivain.

By D.V. Aĭnalov et al.

Quantum and pseudoclassical descriptions of nonrelativistic spinning particles in noncommutative space

We construct a nonrelativistic wave equation for spinning particles in the noncommutative space (in a sense, a theta modification of the Pauli equation). To this end, we consider the nonrelativistic limit of the theta-modified Dirac equation. To complete the consideration, we present a pseudoclassical model (a la Berezin-Marinov) for the corresponding nonrelativistic particle in the noncommutative space. To justify the latter model, we demonstrate that its quantization leads to the theta-modified Pauli equation. We extract theta-modified interaction between a nonrelativistic spin and a magnetic field from such a Pauli equation and construct a theta modification of the Heisenberg model for two coupled spins placed in an external magnetic field. In the framework of such a model, we calculate the probability transition between two orthogonal Einstein-Podolsky-Rosen states for a pair of spins in an oscillatory magnetic field and show that some of such transitions, which are forbidden in the commutative space, are possible due to the space noncommutativity. This allows us to estimate an upper bound on the noncommutativity parameter.

Classical noncommutative electrodynamics with external source

In a U(1)(*)-noncommutative gauge field theory we extend the Seiberg-Witten map to include the (gauge-invariance-violating) external current and formulate-to the first order in the noncommutative parameter-gauge-covariant classical field equations. We find solutions to these equations in the vacuum and in an external magnetic field, when the 4-current is a static electric charge of a finite size a, restricted from below by the elementary length. We impose extra boundary conditions, which we use to rule out all singularities, 1/r included, from the solutions. The static charge proves to be a magnetic dipole, with its magnetic moment being inversely proportional to its size a. The external magnetic field modifies the long-range Coulomb field and some electromagnetic form factors. We also analyze the ambiguity in the Seiberg-Witten map and show that at least to the order studied here it is equivalent to the ambiguity of adding a homogeneous solution to the current-conservation equation.

Gauge invariance and classical dynamics of noncommutative particle theory

We consider a model of classical noncommutative particle in an external electromagnetic field. For this model, we prove the existence of generalized gauge transformations. Classical dynamics in Hamiltonian and Lagrangian form is discussed; in particular, the motion in the constant magnetic field is studied in detail. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3299296]

Casimir interaction between a perfect conductor and graphene described by the Dirac model

We adopt the Dirac model for graphene and calculate the Casimir interaction energy between a plane suspended graphene sample and a parallel plane perfect conductor. This is done in two ways. First, we use the quantum-field-theory approach and evaluate the leading-order diagram in a theory with 2+1-dimensional fermions interacting with 3+1-dimensional photons. Next, we consider an effective theory for the electromagnetic field with matching conditions induced by quantum quasiparticles in graphene. The first approach turns out to be the leading order in the coupling constant of the second one. The Casimir interaction for this system appears to be rather weak. It exhibits a strong dependence on the mass of the quasiparticles in graphene.

Consistency restrictions on maximal electric-field strength in quantum field theory

Quantum field theory with an external background can be considered as a consistent model only if backreaction is relatively small with respect to the background. To find the corresponding consistency restrictions on an external electric field and its duration in QED and QCD, we analyze the mean-energy density of quantized fields for an arbitrary constant electric field E, acting during a large but finite time T. Using the corresponding asymptotics with respect to the dimensionless parameter eET(2), one can see that the leading contributions to the energy are due to the creation of particles by the electric field. Assuming that these contributions are small in comparison with the energy density of the electric background, we establish the above-mentioned restrictions, which determine, in fact, the time scales from above of depletion of an electric field due to the backreaction.

One-loop energy-momentum tensor in QED with electriclike background

We have obtained nonperturbative one-loop expressions for the mean-energy-momentum tensor and current density of Dirac's field on a constant electriclike back-round. One of the goals of this calculation is to give a consistent description of backreaction in such a theory. Two cases of initial states are considered: the vacuum state and the thermal equilibrium state. First, we perform calculations for the vacuum initial state. In the obtained expressions, we separate the contributions due to particle creation and vacuum polarization. The latter contribution,, are related to the Heisenberg-Euler Lagrangian. Then, we Study the case of the thermal initial state. Here, we separate the contributions due to particle creation, vacuum polarization, and the contributions due to the work of the external field on the particles at the initial state. All these contributions are studied in detail, in different regimes of weak and strong fields and low and high temperatures. The obtained results allow us to establish restrictions on the electric field and its duration under which QED with a strong constant electric field is consistent. Under such restrictions, one can neglect the backreaction of particles created by the electric field. Some of the obtained results generalize the calculations of Heisenberg-Euler for energy density to the case of arbitrary strong electric fields.

Nilpotent noncommutativity and renormalization

We analyze renormalizability properties of noncommutative (NC) theories with a bifermionic NC parameter. We introduce a new four-dimensional scalar field model which is renormalizable at all orders of the loop expansion. We show that this model has an infrared stable fixed point (at the one-loop level). We check that the NC QED (which is one-loop renormalizable with a usual NC parameter) remains renormalizable when the NC parameter is bifermionic, at least to the extent of one-loop diagrams with external photon legs. Our general conclusion is that bifermionic noncommutativity improves renormalizability properties of NC theories.