Within the mini-superspace model, brane-like cosmology means performing the variation with respect to the embedding (Minkowski) time τ before fixing the cosmic (Einstein) time t. The departure from the Einstein limit is parametrized by the 'energy' conjugate to τ and characterized by a classically disconnected embryonic epoch. In contrast with canonical quantum gravity, the wavefunction of the Universe is (a) τ dependent and (b) vanishes at the big bang. Hartle-Hawking and Linde proposals dictate discrete 'energy' levels, whereas the Vilenkin proposal resembles α-disintegration.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)