Even though the complete quantum theory admits a semiclassical description of intense fields when treated as external,
or background, fields, the presence of such fields turns out to produce nontrivial quantum effects, such as the Klein
paradox, the Hawking black-hole radiation, and the creation from vacuum of electron-positron pairs by external
electric and supercritical Coulomb fields. These effects require a nonperturbative consideration for their description
within relativistic quantum mechanics, and sometimes also within quantum field theory involving background fields.
The foundation for these theories was laid in the works by the outstanding physicists P.A.M.Dirac, R.Feynman, J.Schwinger,
as well as by many others. In recent years, significat attention has been attracted to the application of these theories
and their corresponding quantum effects to high-energy physics, astrophysics, and condensed matter physics, especially
the physics of graphene and other nanostructures.
Even though all these effects and their applications are discussed at various meetings on a regular basis, many important
problems of the theory remain untouched, and we believe it is timely to discuss the existing unsolved problems of the
nonperturbative approach to theories with background fields, for instance, the problems associated with spontaneous
creation of electron-positron pairs by supercritical Coulomb fields, the problems involving the range of applicability
of nonperturbative QFT methods to neutrino and nanostructure physics, etc. Any other contributions devoted to these
problems and special effects associated with strong fields are certainly welcome.
It is worth noting that the organizing bodies of the Workshop, namely, Lebedev Institute and Tomsk State University
(together with Tomsk State Pedagogical University) were among the pioneers of the work on quantum effects in strong
fields in the former USSR and Russia. In this connection, one can mention the works of A.I.Nikishov, V.I.Ritus,
E.S.Fradkin, A.E.Shabad , I.A.Batalin, D.M.Gitman, V.G.Bagrov, Sh.M.Shwartsman, J.L.Buchbinder, S.P.Gavrilov,
as well as their numerous students.