arXiv subjects
Publications and source records attributed to Avtandil Shurgaia.
A field theoretical perturbation theory in inverse powers of coupling constant is developed which is manifestly covariant in every order of the expansion. A dilatation operator serves as an evolution dynamical one in a scale non-invariant theory.
A simple theoretical model of scalar fields in one spatial dimension with internal symmetry is considered. Assuming the existence of localized classical field configurations, the Schrödinger picture is used to describe their quantum properties. Using the collective coordinates method for the Schrödinger equation allows the development of a perturbation theory that accurately describes the symmetry properties of the theory. Examples of $U(1)$ and $SU (2)$ symmetries are analyzed and the discreteness of the energy of bound states is shown as a result of the symmetry of the theory.
Quantum properties of a (1+1)-dimensional scalar theory on a cylinder with a compact spatial part, namely, $0\leq x\leq L$, are considered. In particular, quantum theory around the classical periodic field configurations is studied and the lifetime of a quantum periodic instanton is estimated.