Single-mode approximation in the quantum theory of a relativistic string. String field

This paper constructs the canonical formalism for the classical string field in independent variables and quantize this field. It is shown how the noncovariant description of the string field is related to covariant Rarita-Schwinger fields with integral spins. The possibility of introducing an interaction is discussed. The simplest vertex is constructed and the widths of resonances with different spins are calculated. The authors use the metric in Minkowski space with signature (+, -, -, -). Summation over repeated indices is understood and the Greek indices take the values 0, 1, 2, 3; the Latin 1, 2, 3