600 research outputs found
Exponentially fitted fifth-order two-step peer explicit methods
The so called peer methods for the numerical solution of Initial Value Problems (IVP) in ordinary differential systems were introduced by R. Weiner et al [6, 7, 11, 12, 13] for solving different types of problems either in sequential or parallel computers. In this work, we study exponentially fitted three-stage peer schemes that are able to fit functional spaces with dimension six. Finally, some numerical experiments are presented to show the behaviour of the new peer schemes for some periodic problems
Long-range correlations in finite nuclei: comparison of two self-consistent treatments
Long-range correlations, which are partially responsible for the observed fragmentation and depletion of low-lying single-particle strength, are studied in the Green's function formalism. The self-energy is expanded up to second order in the residual interaction. We compare two methods of implementing self-consistency in the solution of the Dyson equation beyond Hartree-Fock, for the case of the 16O nucleus. It is found that the energy-bin method and the BAGEL method lead to globally equivalent results. In both methods the final single-particle strength functions are characterized by exponential tails at energies far from the Fermi level
Heisenberg double as braided commutative Yetter-Drinfel'd module algebra over Drinfel'd double in multiplier Hopf algebra case
Based on a pairing of two regular multiplier Hopf algebras and ,
Heisenberg double is the smash product with respect to
the left regular action of on . Let be the
Drinfel'd double, then Heisenberg double is a Yetter-Drinfel'd
-module algebra, and it is also braided commutative by the
braiding of Yetter-Drinfel'd module, which generalizes the results in [10] to
some infinite dimensional cases.Comment: 18 pages. arXiv admin note: text overlap with arXiv:math/0404029 by
other author
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