Hamiltonian dynamics: four dimensional BF-like theories with a compact dimension

Abstract

A detailed Dirac's canonical analysis for a topological four dimensional $BF$-like theory with a compact dimension is developed. By performing the compactification process we find out the relevant symmetries of the theory, namely, the full structure of the constraints and the extended action. We show that the extended Hamiltonian is a linear combination of first class constraints, which means that the general covariance of the theory is not affected by the compactification process. Furthermore, in order to carry out the correct counting of physical degrees of freedom, we show that must be taken into account reducibility conditions among the first class constraints associated to the excited KK modes. Moreover, we perform the Hamiltonian analysis of Maxwell theory written as a $BF$-like theory with a compact dimension, we analyze the constraints of the theory and we calculate the fundamental Dirac's brackets, finally the results obtained are compared with those found in the literature.