177,345 research outputs found
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
Il Sistema Comunitario di Ecogestione ed Audit. Elementi di Analogia con la norma BS 7750, con le norme ISO 9000 e con il sistema di certificazione
No full textOn 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
The behaviour of the lactating sow as affected by two different feeding techniques
No full textIn order to evaluate the behavioural effects of two different feeding techniques, 30 lactating sows were homogeneously allocated to two groups: T1 in which animal received a dry meal at fixed times (8:30 a.m. and 4:00 p.m.) that was ad libitum offered for 30 minutes and group T2 in which sows received a liquid feed that was available all over the day (from 6:00 a.m. to 11:00 p.m.). Sows belonging to group T2 ate more feed (P0.05), the number of piglets weaned per sow and the body weight of piglets at weaning were higher for T2 sows. With regard to behavioural patterns, T2 sows spent more time standing and engaged in eating (P<0.001) and showed improved welfare condition by means of a reduction of abnormal behaviours such as sitting (P<0.01) and bar biting (P<0.01). No significant differences were observed with regard to piglets’ behaviour
APPROXIMATE TIME EVOLUTION OPERATOR OF AN ANHARMONIC OSCILLATOR
No full textWe use an approximation procedure to calculate the form of the time evolution operator of an anharmonic oscillator in the region where perturbation theory is no longer valid
UNITARY AND PSEUDOUNITARY SYMMETRIES IN A GENERALIZED STATISTICS
No full textWe show that the ''guonic'' formalism, based on a g-operator deformation of the Heisenberg-Weyl algebra, preserves, under a Jordan-Schwinger map, unitary (U(N)) and pseudounitary (SU(1,1)) symmetries. This result is a strict consequence of the properties of the operator g
Nota preliminare sul comportamento della latticodeidrogenasi serica e muscolare in suini con razionamento “a secco” ed “in borlanda”
No full textI risultati delle ricerche hanno messo in evidenza che, nella produzione del suino pesante, l'alimentazione "in borlanda" sembra indurre, nei confronti di quella "a secco", un aumento del contenuto in LDH muscolare senza peraltro modificare in maniera statisticamente apprezzabile quella sierica
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
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