Enlarged minisuperspace quantization and black hole singularity resolution
摘要
The intricacy of the gravitational field poses a central challenge for quantum gravity, since a full nonperturbative quantization of the spacetime metric remains analytically intractable. The Kantowski-Sachs minisuperspace model, widely used for the black hole interior, offers a useful simplification but may overly constrain the quantum dynamics near the classical singularity. We therefore propose in this paper an enlarged minisuperspace model that extends the Kantowski-Sachs framework by incorporating an additional metric degree of freedom. This minimal extension enriches the dynamical structure of the model and allows for a more nuanced exploration of the quantum geometry in the black hole interior while maintaining analytical tractability. Applying canonical quantization to this enlarged minisuperspace, we obtain the corresponding Wheeler-DeWitt equation. Remarkably, we find that this model is amenable to exact analytical solution, yielding the wave function of the black hole interior. The resulting wave function