On the finite-size behavior of systems with asymptotically large critical shift

Exact results of the finite-size behavior of the susceptibility in three-dimensional mean spherical model films under Dirichlet-Dirichlet, Dirichlet-Neumann and Neumann-Neumann boundary conditions are presented. The corresponding scaling functions are explicitly derived and their asymptotics close to, above and below the bulk critical temperature $T_c$ are obtained. The results can be incorporated in the framework of the finite-size scaling theory where the exponent $\lambda$ characterizing the shift of the finite-size critical temperature with respect to $T_c$ is smaller than $1/\nu$, with $\nu$ being the critical exponent of the bulk correlation length.Comment: 24 pages, late

Electric Oscillations Generated by Fluctuation Cooper Pairs

A short review of the history and the contemporary numerical calculations of the operation of an electronic device for generation of electric oscillations by negative differential conductivity of a supercooled below the critical temperature superconductor. The superconductor is cooled below the critical temperature at applied small constant electric field, which keeps the superconductor in normal state. To simulate the device operation, beforehand analytical expressions for the conductivity of nano-structured superconductors supercooled below the critical temperature in electric field are used. The numerical analysis meant to alleviate the development of a device shows that the region of negative differential conductivity of the current voltage characteristics leads to generation of electric oscillations. The study of layered high temperature superconductors and radiated electromagnetic waves in space will be an important problem of the future space technology.Comment: Master degree thesis of Aleksander Petkov with scientific advisor Albert Varonov and consultant Todor Mishonov, 20 pages, 16 figures, 1 table; version 2 has the master thesis added to the source files (filename "MasterThesis.pdf", Bulgarian translation

Проведення фінансової реформи IV ст. в Римській імперії

Данча М. І. Проведення фінансової реформи IV ст. в Римській імперії / М. І. Данча // Часопис цивілістики. – 2015. – Вип. 19. – С. 231-235.У статті розглядаються питання визначення та характеристики таких державних відомств, як священні щедроти, особисте майно, преторіанський префект. Встановлюється призначення основних видів податків у Римській імперії у IV ст., які відомства здійснювали оподаткування. Також в аспекті фінансової реформи розглядається введення нової золотої монети – соліда, соціально-правове становище таких прошарків населення, як колони, взаємозв’язок фінансових органів, їх роль у державному апараті.В статье рассматриваются вопросы определения и характеристики таких государственных ведомств, как священные щедроты, личное имущество, преторианский префект. Устанавливается назначение основных видов налогов в Римской империи в IV в., какие ведомства осуществляли налогообложение. Также в аспекте финансовой реформы рассматривается введение новой золотой монеты-солида, социально-правовое положение таких слоёв населения, как колонны, взаимосвязь финансовых органов, их роль в государственном аппарате.The article deals with the definition and characteristics of other state institutions assacred bounties, personal property, praetorian prefect. Set the main purpose taxes in the Roman Empirein IVst., Who carried out the tax office. Also in terms of financial reform isseenentering a new golden solidus monety-, social and legal status of population groups as columns, the relationship of financial authorities, the irrolein the state apparatus

On the Finite-Temperature Generalization of the C-theorem and the Interplay between Classical and Quantum Fluctuations

The behavior of the finite-temperature C-function, defined by Neto and Fradkin [Nucl. Phys. B {\bf 400}, 525 (1993)], is analyzed within a d -dimensional exactly solvable lattice model, recently proposed by Vojta [Phys. Rev. B {\bf 53}, 710 (1996)], which is of the same universality class as the quantum nonlinear O(n) sigma model in the limit $n\to \infty$. The scaling functions of C for the cases d=1 (absence of long-range order), d=2 (existence of a quantum critical point), d=4 (existence of a line of finite temperature critical points that ends up with a quantum critical point) are derived and analyzed. The locations of regions where C is monotonically increasing (which depend significantly on d) are exactly determined. The results are interpreted within the finite-size scaling theory that has to be modified for d=4. PACS number(s): 05.20.-y, 05.50.+q, 75.10.Hk, 75.10.Jm, 63.70.+h, 05.30-d, 02.30Comment: 15 pages LATEX, ioplppt.sty file used, 6 EPS figures. Some changes made in section V (on finite-size scaling interpretation of the results obtained

Fluctuation - induced forces in critical fluids

The current knowledge about fluctuation - induced long - ranged forces is summarized. Reference is made in particular to fluids near critical points, for which some new insight has been obtained recently. Where appropiate, results of analytic theory are compared with computer simulations and experiments.Comment: Topical review, 24 pages RevTeX, 6 figure