Yeong-Chuan Kao

Worldvolume Uncertainty Relations for D-Branes

By quantizing an open string ending on a D-brane in a nontrivial supergravity background, we argue that there is a new kind of uncertainty relation on a D-brane worldvolume. Furthermore, we fix the form of the uncertainty relations and their dependence on the string coupling constant by requiring them to be consistent with various string theory and M theory dualities. In this way we find a web of uncertainties of spacetime for all kinds of brane probes, including fundamental strings, D-branes of all dimensions as well as M theory membranes and fivebranes.

K+→π++γ̃γ̃ in spontaneously broken supersymmetric models

Abstract We study the decay K + →π + γ γ in models with spontaneous supersymmetry breaking and find that it is generally suppressed relative to the decay K + Λπ + ν ν of the conventional model, except possibly for a class of models where the squark masses are generated by radiative corrections from a much larger supersymmetry breaking scale. For a small range of squark and photino parameters, the cascade process K + →π + π 0 →π + γ γ will become dominant over the ν ν mode. We also comment on the possibility of probing the neutrino mass through the K + →π + π 0 →π + ν ν cascade decay.

Bulk versus edge in the quantum Hall effect

The manifestation of the bulk quantum Hall effect on edge is the chiral anomaly. The chiral anomaly {ital is} the underlying principle of the {open_quote}{open_quote}edge approach{close_quote}{close_quote} of quantum Hall effect. In that approach, {sigma}{sub {ital xy}} {ital should} {ital not} be taken as the conductance derived from the space-local current-current correlation function of the pure one-dimensional edge problem. {copyright} {ital 1996 The American Physical Society.}

Background fields, composite operators, and asymptotic freedom

Abstract The gluon self-energy in a covariant background gauge is related to the self-energy in an ordinary covariant gauge and the two-point function of a composite operator which enters the Kugo-Ojima confinement criterion. Asymptotic freedom is tied to anti-screening of global color.

On radiatively induced fermion mass in (2 + 1)-dimensional gauge theory with a Chern-Simons term

We study the dynamical generation of parity-odd fermion mass in (2+1)-dimensional topologically massive gauge theory. To one-loop order, the temperature dependence of the induced fermion mass is calculated. The implications of our study pertinent to some recent results concerning the Chern–Simons terms are discussed.

Another look at charge fractionalization at finite temperature

We study again the phenomenon of charge fractionalization at finite temperature. Our calculations are done in a framework in which the connection between the induced fermion number and the chiral anomaly is manifest. We find that the fractional fermion number induced on a soliton decreases as temperature rises and vanishes at infinite temperature at one-loop level. These results are consistent with previous studies. As an application of our approach, we have also studied the behavior of the induced Chern-Simons term in the (

Schwinger model on a half-line

2+1

THE MEISSNER EFFECT AND INFINITE CONDUCTIVITY IN ANYON SUPERCONDUCTOR AT FINITE TEMPERATURE

)-dimensional QED at finite temperature.

High temperature behavior of the fermion number breaking condensate around a monopole

We study the Schwinger model on a half-line in this paper. In particular, we investigate the behavior of the chiral condensate near the edge of the line. The effect of the chosen boundary condition is emphasized. The extension to the finite temperature case is straightforward in our approach.

Multiple-effect diffusion solar still coupled with a vacuum-tube collector and heat pipe

We study the conductivity tensor for the pure anyon system at finite temperature by calculating the electromagnetic response function Kμν(ω, k) in the random-phase approximation. We find that the conductivity is indeed infinite through the vanishing of the renormalized Chern-Simons term for the statistical gauge fields in the limit k=0, ω→0. To study the Meissner effect at finite temperature, others have looked at Kµν(ω, k) in the limit ω=0, k→0. We compare the results and make some comments.