We present a microscopic approach in the framework of Sklyanin's quantum
separation of variables (SOV) for the exact solution of 1+1-dimensional quantum
field theories by integrable lattice regularizations. Sklyanin's SOV is the
natural quantum analogue of the classical method of separation of variables and
it allows a more symmetric description of classical and quantum integrability
w.r.t. traditional Bethe ansatz methods. Moreover, it has the advantage to be
applicable to a more general class of models for which its implementation gives
a characterization of the spectrum complete by construction. Our aim is to
introduce a method in this framework which allows at once to derive the
spectrum (eigenvalues and eigenvectors) and the dynamics (time dependent
correlation functions) of integrable quantum field theories (IQFTs). This
approach is presented for a paradigmatic example of relativistic IQFT, the
sine-Gordon model.Comment: 8 pages; invited contribution to the Proceedings of the XVIIth
INTERNATIONAL CONGRESS ON MATHEMATICAL PHYSICS, August 2012, Aalborg,
Danemark; accepted for publication on the ICMP12 Proceedings by World
Scientific. The material here presented is strictly connected to that
introduced in arXiv:0910.3173 and arXiv:1204.630