  A physical interpretation of translation-invariant polarons and bipolarons is
presented, some results of their existence are discussed. Consideration is
given to the problem of quantization in the vicinity of the classical solution
in the quantum field theory. The lowest variational estimate is obtained for
the bipolaron energy E(\eta) with E(0)=-0,440636\alpha^2, where \alpha is a
constant of electron-phonon coupling, \eta is a parameter of ion binding.
