(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

Dynamical Symmetry Breaking on Langevin Equation : Nambu ⋅\cdot Jona-Lasinio Model

In order to investigate dynamical symmetry breaking, we study Nambu$\cdot$Jona-Lasinio model in the large-N limit in the stochastic quantization method. Here in order to solve Langevin equation, we impose specified initial conditions and construct ``effective Langevin equation'' in the large-N limit and give the same non-perturbative results as path-integral approach gives. Moreover we discuss stability of vacuum by means of ``effective potential''.Comment: 12 pages (Plain TeX), 7 figures(not included, sorry!), CHIBA-EP-6

Non-axisymmetric oscillations of rapidly rotating relativistic stars by conformal flatness approximation

We present a new numerical code to compute non-axisymmetric eigenmodes of rapidly rotating relativistic stars by adopting spatially conformally flat approximation of general relativity. The approximation suppresses the radiative degree of freedom of relativistic gravity and the field equations are cast into a set of elliptic equations. The code is tested against the low-order f- and p-modes of slowly rotating stars for which a good agreement is observed in frequencies computed by our new code and those computed by the full theory. Entire sequences of the low order counter-rotating f-modes are computed, which are susceptible to an instability driven by gravitational radiation.Comment: 3 figures. To appear in Phys.Rev.

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 $A \approx$ 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 $F_2, xF_3, F_L$ and $F_2^{c\bar{c}}$ and their parametrizations, the measurement of the gluon density, recent theoretical work on the small $x$ behavior of structure functions, theoretical and experimental results on $\alpha_s$, the direct photon cross section, and a discussion of the event rates in the high $p_T$ range at Tevatron and the high $Q^2$ 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