On the concept of time and the origin of the cosmological temperature

A Born-Oppenheimer factorization of the Schroedinger wave function which is appropriate to the problem where light matter follows heavy gravity adiabatically (the matter mass scale being much smaller than the Planck mass) is presently applied to cosmology, in conjunction with the Hartle-Hawking (1983) wavefunction-of-the-universe approach. The model is sufficiently characteristic to invite the firm conjecture that, in the presence of bounce behind the horizon and in the presence of weak violations of conformal coupling, the conclusions obtained are quite general.