1,898 research outputs found
Renormalization theory for the Fulde-Ferrell-Larkin-Ovchinnikov states at
Within the renormalization group framework we study the stability of
superfluid density wave states, known as Fulde-Ferrell-Larkin-Ovchinnikov
(FFLO) phases, with respect to thermal order-parameter fluctuations in two and
three-dimensional () systems. We analyze the
renormalization-group flow of the relevant ordering wave-vector .
The calculation indicates an instability of the FFLO-type states towards either
a uniform superfluid or the normal state in and . In
this is signaled by being renormalized towards zero, corresponding
to the flow being attracted either to the usual Kosterlitz-Thouless fixed-point
or to the normal phase. We supplement a solution of the RG flow equations by a
simple scaling argument, supporting the generality of the result. The tendency
to reduce the magnitude of by thermal fluctuations persists in
, where the very presence of long-range order is immune to thermal
fluctuations, but the effect of attracting towards zero by the flow
remains observed at
The application of the Schur-Weyl duality in the one-dimensional Hubbard model
We present the application of the Schur-Weyl duality in the one-dimensional
Hubbard model in the case of half-filled system of any numer of atoms. We
replace the actions of the dual symmetric and unitary groups in the whole
Hilbert space by the actions of the dual groups in the spin and pseudo-spin
spaces. The calculations significantly reduce the dimension of the eigenproblem
of the one-dimensional Hubbard model.Comment: 16 pages, 2 table
Dimensional crossovers and Casimir forces for the Bose gas in anisotropic optical lattices
We consider the Bose gas on a -dimensional anisotropic lattice employing
the imperfect (mean-field) gas as a prototype example. We study the dimensional
crossover arising as a result of varying the dispersion relation at finite
temperature . We analyze in particular situations where one of the relevant
effective dimensionalities is located at or below the lower critical dimension,
so that the Bose-Einstein condensate becomes expelled from the system by
anisotropically modifying the lattice parameters controlling the kinetic term
in the Hamiltonian. We clarify the mechanism governing this phenomenon.
Subsequently we study the thermodynamic Casimir effect occurring in this
system. We compute the exact profile of the scaling function for the Casimir
energy. As an effect of strongly anisotropic scale invariance, the Casimir
force below or at the critical temperature may be repulsive even for
periodic boundary conditions. The corresponding Casimir amplitude is universal
only in a restricted sense, and the power law governing the decay of the
Casimir interaction becomes modified. We also demonstrate that, under certain
circumstances, the scaling function is constant for suffciently large values of
the scaling variable, and in consequence is not an analytical function. At the Casimir-like interactions reflect the structure of the correlation
function, and, for certain orientations of the confining walls, show
exponentially damped oscillatory behavior so that the corresponding force is
attractive or repulsive depending on the distance.Comment: 12 pages, 5 figures, major changes in the manuscrip
Altmanʼs Model as an Instrument for the Evaluation of the Financial Situation of the Alma Market S.A.
Using a set of standard financial statements, you can designate a large
number of economic and financial indicators that show the condition of the
company. A large number of indicators gives a lot of opportunities to assess the
health of the company. However, there is a risk of introduction of information
chaos, which instead help in the assessment of the economic and social situation
of the firm may make it harder for making analyses. Comes with the help
of LDA, which is becoming more and more popular method to synthetic
evaluation of the financial health of enterprises on the basis of the available
financial statements. It not only allows for the simultaneous and consistent use,
at least a couple of economic and financial information, but also takes into
account the ability of certain indicators of financial and economic bankruptcy
predictor. The essence of this method involves applying a discriminatory
function linear, often called discriminatory model. The calculated value to the
total health assessment by subject classification of it to one of two groups,
businesses operating without any visible signs of problems in the economic
sphere or at risk of bankruptcy. The main objective of the article was reached to
Alma Market S.A. not threatened bankruptcy in the test for years to come. The
article has been following the research hypothesis: An Alma Market S.A. does not run the risk of bankruptcy in all the years of the period considered. This
hypothesis is confirmed, because throughout the period, the level of this
indicator was higher than Altmanʼs equation, and therefore we can bankruptcy
2,60 except in accordance with the theory of Altman
Fast loans – method of raising liqyudity
This article describes the essence of fast, instant cash loans which can raise liquidity or be
the cause of growing indebtedness. The purpose of this article is to show the advantages and
disadvantages of fast loans and attempt to compare different loan options available to the client on
the Polish market. In this paper an analysis of the costs, repayment terms and specificities loan
offers, which showed that fast loans perfect solution for those conscious consequences borrowings
The influence of droplet size on line tension
Within the effective interfacial Hamiltonian approach we evaluate the excess
line free energy associated with cylinder-shaped droplets sessile on a
stripe-like chemical inhomogeneity of a planar substrate. In the case of
short-range intermolecular forces the droplet morphology and the corresponding
expression for the line tension - which includes the inhomogeneity finite width
effects - are derived and discussed as functions of temperature and increasing
width. The width-dependent contributions to the line tension change their
structure at the stripe wetting temperature T_W1: for T<T_W1 they decay
exponentially while for T>T_W1 the decay is algebraic. In addition, a geometric
construction of the corresponding contact angle is carried out and its
implications are discussed
- …
