Abstracts

Branislav Sazdovic

T-duality between effective string theories

We consider the open bosonic string moving in the constant background. We investigate whether the solving of the constraints obtained by applying the Dirac procedure to the boundary conditions of the open string, which leads to effective closed string theory and the T-dualization procedure are commutative. We consider the string with mixed boundary conditions. We start by applying the Dirac procedure to these conditions, which results in two parameter dependent constraints. These constraints are solved and for the solution the effective theory is obtained. On the other hand applying the T-dualization procedure to the initial theory one obtains the T-dual theory. As usual, the form of the theory is such that as if the T-dual boundary conditions are already chosen, so that the T-dual coordinates satisfy exactly the opposite set of the boundary conditions then the corresponding coordinates of the initial string. We apply the Dirac procedure to the T-dual boundary conditions, obtain the parameter dependent constraints and solve them to obtain the T-dual effective theory. We show that the effective theories of the initial and T-dual theory remain T-dual, and find the effective T-duality coordinate transformation laws.