Unitary evolution for anisotropic quantum cosmologies: models with variable spatial curvature

Understand

Contrary to the general belief, there has recently been quite a few examples of unitary evolution of quantum cosmological models.

• The present work gives more examples, namely Bianchi type VI and type II.
• These examples are important as they involve varying spatial curvature unlike the most talked about homogeneous but anisotropic cosmological models like Bianchi I, V and IX.
• We exhibit either explicit example of the unitary solutions of the Wheeler-DeWitt equation, or at least show that a self-adjoint extension is possible.