Amplitudes for the Bosonic String with Boundaries

We deal with the problem of the computation of amplitudes for the bosonic Polyakov string with boundaries and show that both conformal invariance and reparametrisation invariance are maintained in critical dimensional d = 26 as the case without boundaries. The amplitudes of the bosonic, closed oriented Polyakov string with boundaries are formulated aa integral over moduli space with respect to the Weil-Petersson measure.