Dispersive approach to QCD and hadronic contributions to electroweak observables

The dispersive approach to QCD is briefly overviewed and its application to the assessment of hadronic contributions to electroweak observables is discussed.Comment: Talk given at 12th International Conference on Quark Confinement and the Hadron Spectrum, 29 August - 3 September 2016, Thessaloniki, Greece; 10 pages, 3 figure

Inclusive tau lepton hadronic decay in the framework of dispersive approach to QCD

The dispersive approach to QCD and its applications to inclusive tau lepton hadronic decay and hadronic vacuum polarization function are briefly discussed.Comment: Based on talks given at the 12th Workshop on Nonperturbative QCD (10 - 13 June 2013, Paris, France) and the 16th Lomonosov Conference on Elementary Particle Physics (22 - 28 August 2013, Moscow, Russia); 4 pages, 1 figur

Calculation of the R-ratio of e+e−→e^{+}e^{-}\to hadrons at the higher-loop levels

The calculation of the R-ratio of electron-positron annihilation into hadrons is discussed. The method, which enables one to properly account for all the effects due to continuation of the spacelike perturbative results into the timelike domain at an arbitrary loop level, is delineated.Comment: Based on talk given at the 18th Lomonosov Conference on Elementary Particle Physics (24 - 30 August 2017, Moscow, Russia); 7 page

The QCD analytic effective charge and its dependence on the pion mass

A new model for the QCD analytic running coupling, which incorporates the effects due to the $\pi$ meson mass, is proposed. The properties of this invariant charge in spacelike and timelike regions are examined. Its main distinctive features are a finite infrared limiting value, which depends on the pion mass, and the "plateau-like" behavior in the deep infrared domain of the timelike region.Comment: Talk given at Eighth Workshop on Nonperturbative QCD, 7 - 11 June 2004, Paris, France; 6 pages, 2 EPS figure