7,549 research outputs found
Effective field theory approach to N=4 supersymmetric Yang-Mills at finite temperature
We study the perturbation expansion of the free energy of N=4 supersymmetric
SU(N) Yang-Mills at finite temperature in powers of 't Hooft's coupling g^2 N
in the large N limit. Infrared divergences are controlled by constructing a
hierarchy of two 3 dimensional effective field theories. This procedure is
applied to the calculation of the free energy to order (g^2 N)^(3/2), but it
can be extended to higher order corrections.Comment: LaTeX, 10 pages, 1 figure, uses eps
Complexified sigma model and duality
We show that the equations of motion associated with a complexified
sigma-model action do not admit manifest dual SO(n,n) symmetry. In the process
we discover new type of numbers which we called `complexoids' in order to
emphasize their close relation with both complex numbers and matroids. It turns
out that the complexoids allow to consider the analogue of the complexified
sigma-model action but with (1+1)-worldsheet metric, instead of
Euclidean-worldsheet metric. Our observations can be useful for further
developments of complexified quantum mechanics.Comment: 15 pages, Latex, improved versio
Equivalence between various versions of the self-dual action of the Ashtekar formalism
Different aspects of the self-dual (anti-self-dual) action of the Ashtekar
canonical formalism are discussed. In particular, we study the equivalences and
differences between the various versions of such an action. Our analysis may be
useful for the development of an Ashtekar formalism in eight dimensions.Comment: 10 pages, Latex, minor correction
About a Coincidente Index for the State of the Economy
The construction of coincident indexes for the economic activity of a country is a common practice since the fifties. The methodologies vary from heuristic methods to probabilistic or statistical ones. In this paper, we present a new procedure for estimating a coincient index of the state of the economy which is optimum in a statiscal sense. This procedure is based on state space models that do possess the steady-state property.We apply our methodology for computing a coincident index for the Colombian economy.State of the economy, Coincidente Index, State Space Models.
General Approach to Functional Forms for the Exponential Quadratic Operators in Coordinate-Momentum Space
In a recent paper [Nieto M M 1996 Quantum and Semiclassical Optics, 8 1061;
quant-ph/9605032], the one dimensional squeezed and harmonic oscillator
time-displacement operators were reordered in coordinate-momentum space. In
this paper, we give a general approach for reordering multi-dimensional
exponential quadratic operator(EQO) in coordinate-momentum space. An explicit
computational formula is provided and applied to the single mode and
double-mode EQO through the squeezed operator and the time displacement
operator of the harmonic oscillator.Comment: To appear in J. Phys. A: Mathematics and Genera
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