arXiv subjects

V. I. Yasnov

Publications and source records attributed to V. I. Yasnov.

3 recordsLinked to original sources

arXiv2000

Renormalization Scheme and Higher Loop Stability in Hadronic $τ$ Decay within Analytic Perturbation Theory

We apply an analytic description to the inclusive decay of the $τ$ lepton. We argue that this method gives not only a self-consistent description of the process both in the timelike region by using the initial expression for $R_τ$ and in the spacelike domain by using the analytic properties of the hadronic correlator, but also leads to the fact that theoretical uncertainties associated with unknown higher-loop contributions and renormalization scheme dependence can be reduced dramatically.

hep-ph↗

arXiv1998

Analytic Perturbation Theory and Renormalization Scheme Dependence in Tau Decay

We apply analytic perturbation theory in next-to-next-to-leading order to inclusive semileptonic $τ$-decay and study the renormalization scheme dependence. We argue that the renormalization scheme ambiguity is considerably reduced in the analytic perturbation theory framework and we obtain a rather stable theoretical prediction.

hep-ph↗

arXiv1996

Hamiltonian reduction of free particle motion on group SL(2, ${\Bbb R}$)

The structure of the reduced phase space arising in the Hamiltonian reduction of the phase space corresponding to a free particle motion on the group ${\rm SL}(2, {\Bbb R})$ is investigated. The considered reduction is based on the constraints similar to those used in the Hamiltonian reduction of the Wess--Zumino--Novikov--Witten model to Toda systems. It is shown that the reduced phase space is diffeomorphic either to the union of two two--dimensional planes, or to the cylinder $S^1 \times {\Bbb R}$. Canonical coordinates are constructed for the both cases, and it is shown that in the first case the reduced phase space is symplectomorphic to the union of two cotangent bundles $T^*({\Bbb R})$ endowed with the canonical symplectic structure, while in the second case it is symplectomorphic to the cotangent bundle $T^*(S^1)$ also endowed with the canonical symplectic structure.

hep-th↗