X iv : h ep - t h / 99 06 06 7 v 1 9 J un 1 99 9 Magnetic fields and factored two - spheres

ar X iv : h ep - t h / 99 06 02 9 v 1 3 J un 1 99 9

ar X iv : h ep - p h / 95 06 25 9 v 1 7 J un 1 99 5 CERN – TH / 95 – 83 hep - ph / 9506259 May 1995 MULTIPLE HARD

ar X iv : h ep - t h / 99 06 07 2 v 1 9 J un 1 99 9 HD – THEP – 99 – 11 Hamiltonian Approach to Lagrangian Gauge Symmetries

We reconsider the problem of finding all local symmetries of a La-grangian. Our approach is completely Hamiltonian without any reference to the associated action. We present a simple algorithm for obtaining the restrictions on the gauge parameters entering in the definition of the generator of gauge transformations.

ar X iv : h ep - t h / 99 06 06 9 v 1 9 J un 1 99 9 UMTG – 219 Soliton S matrices for the critical A ( 1 ) N − 1 chain

We compute by Bethe Ansatz both bulk and boundary hole scattering matrices for the critical A (1) N−1 quantum spin chain. The bulk S matrix coincides with the soliton S matrix for the A (1) N−1 Toda field theory with imaginary coupling. We verify our result for the boundary S matrix using a generalization of the Ghoshal-Zamolodchikov boundary crossing relation.

ar X iv : h ep - p h / 99 06 27 2 v 1 7 J un 1 99 9 DISSIPATIVE CONTRIBUTIONS TO ε ′

The time evolution and decay of the neutral kaon system can be described using quantum dynamical semigroups. Non-standard terms appear in the expression of relevant observables; they can be parametrized in terms of six, new phenomenological constants. We discuss how the presence of these constants affects the determination of the parameter ε ′ /ε.