Reconstruction of the bubble nucleating potential.

We calculate analytically the bubble nucleation rate in a model of rst order in ation which is able to produce large scale structure. The computation includes the rst-order departure from the thin-wall limit, the explicit derivation of the pre-exponential factor, and the gravitational correction. The resulting bubble spectrum is then compared with constraints from the large scale structure and the microwave background. We show that there are models which pass all the constraints and produce bubble-like perturbations of interesting size. Furthermore, we show that it is in principle possible to reconstruct completely the in ationary twoeld potential from observations. PACS: 98.80 Cq, 98.80 Es Typeset using REVTEX