4 papers
Quantum spin tunneling in a soluble quasi-spin model: An angle-based potential description
D. Galetti, C. L. Lima, B. M. Pimentel
We propose an approach which allows to construct and use a potential function written in terms of an angle variable to describe interacting spin systems. We show how this can be im…
Irreducibility and Compositeness in q-Deformed Harmonic Oscillator Algebras
D. Galetti, J. T. Lunardi, B. M. Pimentel +1
q-Deformed harmonic oscillator algebra for real and root of unity values of the deformation parameter is discussed by using an extension of the number concept proposed by Gauss, na…
Generalization of the Hamilton-Jacobi approach for higher order singular systems
B. M. Pimentel, R. G. Teixeira
We generalize the Hamilton-Jacobi formulation for higher order singular systems and obtain the equations of motion as total differential equations. To do this we first study the co…
Causal Propagators for the Second Order Wilson Loop
B. M. Pimentel, J. L. Tomazelli
We evaluate the Wilson loop at second order in general non-covariant gauges by means of the causal principal-value prescription for the gauge- dependent poles in the gauge-boson pr…