1,721,030 research outputs found
On the solutions of the vacuum Cartan equation in Metric Affine Gravity
No full textWe review some particular solutions of the vacuum Cartan equation for the non-Riemannian part of the connection in Metric Affine Gravity, by exploiting a variational approach. As application we show how a quite general non Riemannian model gives a Proca type equation for the trace of the non metricity 1-form Q
HARMONIC OSCILLATOR WITH GENERALIZED STATISTICS
No full textUsing the formalism of g-operator we find a generalization of the harmonic-oscillator algebra, which contains as particular cases the boson and fermion oscillators. The form of the creation and annihilation operators is obtained as a function of two operators, alpha and beta, which satisfy a certain new algebra of the Lie-admissible type
Heisenberg equation and constants of the motion for an anharmonic oscillator in the high-frequency limit
No full textUsing the best approximation of the time evolution operator of a quartic oscillator in the high-frequency limit, we derive its equation of the motion in the Heisenberg picture and show that such an anharmonic oscillator admits a wider class of constants of the motion than the standard harmonic oscillator
APPROXIMATION METHOD FOR THE PARTITION-FUNCTION OF AN ANHARMONIC-OSCILLATOR GAS
No full textWe use an approximation procedure to find the partition function of a gas composed by anharmonic oscillators in a region where perturbation theory breaks down. The results are still quite accurate for small values of the coupling constant
Approximation procedure for an anharmonic oscillator with cubic and quartic terms
No full textWe use -after a shift transformation of the variable- the Burrows, Cohen and Feldmann approximation procedure to solve the problem of finding the energy eigenvalues for an anharmonic oscillator with cubic and quartic terms subjected to a linear external potential. Both low- and high-frequency limits are considered. A first application is given by deriving (in the high-frequency case) the partition function of a gas composed of such anharmonic oscillators. We also exploit the recently proved formal equivalence between a high-frequency anharmonic oscillator (in the approximation considered) and an infinitesimally deformed harmonic oscillator to introduce SU(2) and SU(1, 1) algebras for the anharmonic oscillator with cubic and quartic terms
q-parameter dependence of a gas in equilibrium with a deformed solid
No full textWe show that the main thermodynamical quantities of a gas in equilibrium with a deformed solid (composed by q-oscillators) exhibit a dependence on the deformation parameter of the lattice oscillators
Non-invariant ground states, thermal average, and generalized fermionic statistics
No full textWe present an approach to generalized fermionic statistics which relates the existence of a generalized statistical behaviour to non-invariant ground states. Considering the thermal average of an operator generalization of the Heisenberg algebra, we get an occupation number which depends on the degree of mixing between symmetric and antisymmetric sectors of the ground state. A natural prescription is given for the construction of a supersymmetric statistics. We also show that the structure of the vacuum, and therefore the statistical behaviour of the system, can be accounted for in terms of a second-order phase transition. (C) 1999 Published by Elsevier Science B.V. All rights reserved
VARIATIONAL APPROACH TO GENERALIZED STATISTICS
No full textBy means of the Schwinger variational principle, we show that a field theory with a linearly realized symmetry admits the generalized g-statistics as a possible solution
AN ALTERNATIVE APPROACH TO DEFORMED STATISTICS
No full textStarting from general assumptions about creation and annihilation operators we propose a new generalized approach to deformed statistics, which permits to distinguish between two different situations; the first, in which we may define an intrinsically defined statistics, and the second one, in which this is not possible, because the symmetry properties of the system are determined by the vacuum state. The dynamical evolution of the generalized particles (guons) is derived by exploiting the Lie-admissible structure of the g-algebra
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