Quantum fluctuations and CMB anisotropies in one-bubble open inflation models

We first develop a method to calculate a complete set of mode functions whichdescribe the quantum fluctuations generated in one-bubble open inflationmodels. We consider two classes of models. One is a single scalar field modelproposed by Bucher, Goldhaber and Turok and by us as an example of the openinflation scinario, and the other is a two-field model such as the``supernatural'' inflation proposed by Linde and Mezhlumian. In both cases weassume the difference in the vacuum energy density between inside and outsidethe bubble is negligible. There are two kinds of mode functions. One kind hasusual continuous spectrum and the other has discrete spectrum withcharacteristic wavelengths exceeding the spatial curvature scale. The lattercan be further devided into two classes in terms of its origin. One is calledthe de Sitter super-curvature mode, which arises due to the global spacetimestructure of de Sitter space, and the other is due to fluctuations of thebubble wall. We calculate the spectrum of quantum fluctuations in these modelsand evaluate the resulting large angular scale CMB anisotropies. We find thereare ranges of model parameters that are consistent with observed CMBanisotropies.Comment: 22 pages revtex file, 12 postscript figures, tarred, gzippe