26,801 research outputs found
(D+1)-Dimensional Formulation for D-Dimensional Constrained Systems
D-dimensional constrained systems are studied with stochastic Lagrangian
and\break Hamiltonian. It is shown that stochastic consistency conditions are
second class constraints and Lagrange multiplier fields can be determined in
(D+1)-dimensional canonical formulation. The Langevin equations for the
constrained system are obtained as Hamilton's equations of motion where
conjugate momenta play a part of noise fields.Comment: 10 pages (Plain TeX), CHIBA-EP-58-Re
Non-perturbative gadget for topological quantum codes
Many-body entangled systems, in particular topologically ordered spin systems
proposed as resources for quantum information processing tasks, often involve
highly non-local interaction terms. While one may approximate such systems
through two-body interactions perturbatively, these approaches have a number of
drawbacks in practice. Here, we propose a scheme to simulate many-body spin
Hamiltonians with two-body Hamiltonians non-perturbatively. Unlike previous
approaches, our Hamiltonians are not only exactly solvable with exact ground
state degeneracy, but also support completely localized quasi-particle
excitations, which are ideal for quantum information processing tasks. Our
construction is limited to simulating the toric code and quantum double models,
but generalizations to other non-local spin Hamiltonians may be possible.Comment: 13 pages, 8 figures, PRL Accepte
Theoretical study of the decay-out spin of superdeformed bands in the Dy and Hg regions
Decay of the superdeformed bands have been studied mainly concentrating upon
the decay-out spin, which is sensitive to the tunneling probability between the
super- and normal-deformed wells. Although the basic features are well
understood by the calculations, it is difficult to precisely reproduce the
decay-out spins in some cases. Comparison of the systematic calculations with
experimental data reveals that values of the calculated decay-out spins scatter
more broadly around the average value in both the 150 and 190
regions, which reflects the variety of calculated tunneling probability in each
band.Comment: 6 pages 4 figures (30 PS files). To appear in Proc. of NS2000
(Nuclear Structure 2000) conf., at MSU, 15-19 Aug., 200
Summary of Working Group I: Hadron Structure
A summary is given on the main aspects which were discussed by the working
group. They include new results on the deep inelastic scattering structure
functions and and their parametrizations, the
measurement of the gluon density, recent theoretical work on the small
behavior of structure functions, theoretical and experimental results on
, the direct photon cross section, and a discussion of the event
rates in the high range at Tevatron and the high range at HERA, as
well as possible interpretations.Comment: 22 pages latex, including 8 figures (ps,eps), to appear in the
Proceedings of the International Conference on Deep Inelastic Scattering,
Chicago, April 1997, AI
- …