41 research outputs found
Edge States and Entanglement Entropy
It is known that gauge fields defined on manifolds with spatial boundaries
support states localized at the boundaries. In this paper, we demonstrate how
coarse-graining over these states can lead to an entanglement entropy. In
particular, we show that the entanglement entropy of the ground state for the
quantum Hall effect on a disk exhibits an approximate ``area " law.Comment: 16 pages, minor corrections and futher details adde
Charged Scalar Pair Production in Strong-Field Photon-Photon Interaction
Following the pioneering work of H. Reiss [1], we provide a covariant
calculation of the charged scalar particle pair production. The calculation is
facilitated by the use of two-dimensional Bessel functions and light-font
coordinates.Comment: 8 page
Novel Edge States in Self-Dual Gravity
In contrast to the Einstein-Hilbert action, the action for self-dual gravity
contains vierbeins. They are eleminated at the level of observables by an
gauge condition implied by the action. We argue that despite
this condition, new "edge" or superselected state vectors corresponding to maps
of the spheres at infinity to arise. They
are characterised by new quantum numbers and they lead to mixed states. For
black holes, they arise both at the horizon and the spatial infinity and may be
relevant for the black hole information paradox. Similar comments can be made
about the Einstein-Palatini action which uses vierbeins.Comment: 15 pages, reference added, some minor notational changes - no changes
in conclusio
Heavy Meson Radiative Decays and Light Vector Meson Dominance
Electromagnetic interactions are introduced in the effective chiral
Lagrangian for heavy mesons which includes light vector particles. A suitable
notion of vector meson dominance is formulated. The constraints on the heavy
meson -light vector and heavy meson-light pseudoscalar coupling constants are
obtained using experimental D^* \ra D \, \gamma branching ratios. These
constraints are compared with values estimated from semi-leptonic transition
amplitudes as well as from extension of the light meson coupling pattern.
Application to the heavy baryon spectrum in the ``bound state " model is made.Comment: 14 pages, 1 figure as compressed uuencoded file appended at the end
of the paper, report# SU-4240-58