Gravidade quântica, a origem do tempo e a flecha do tempo (1992)

sexta-feira, abril 06, 2012

Quantum Gravity, the Origin of Time and Time's Arrow


(Submitted on 2 Sep 1992)

The local Lorentz and diffeomorphism symmetries of Einstein's gravitational theory are spontaneously broken by a Higgs mechanism by invoking a phase transition in the early Universe, at a critical temperature $T_c$ below which the symmetry is restored. The spontaneous breakdown of the vacuum state generates an external time and the wave function of the Universe satisfies a time dependent Schrodinger equation, which reduces to the Wheeler-deWitt equation in the classical regime for $T < T_c$, allowing a semi-classical WKB approximation to the wave function. The conservation of energy is spontaneously violated for $T > T_c$ and matter is created fractions of seconds after the big bang, generating the matter in the Universe. The time direction of the vacuum expectation value of the scalar Higgs field generates a time asymmetry, which defines the cosmological arrow of time and the direction of increasing entropy as the Lorentz symmetry is restored at low temperatures.

Comments: 37 pages

Subjects: General Relativity and Quantum Cosmology (gr-qc)

Journal reference: Found.Phys. 23 (1993) 411-437


Report number: UTPT--92--09


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