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arXiv · 0805.3971

Can Quantum Gravitational Effects Influence the Entire History of the Universe?

Edésio M. Barboza Jr.·Nivaldo A. Lemos
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Abstract

In this work, a flat Friedmann-Robertson-Walker (FRW) universe with dust and a cosmological constant is quantized. By means of a canonical transformation, the classical Hamiltonian is reduced to that of either a harmonic oscillator or anti-oscillator, depending on whether $Λ<0$ or $Λ>0$, respectively. In this way exact solutions to the Wheeler-DeWitt equation can easily be obtained. It turns out that a positive cosmological constant alone may account for an early inflationary regime and a later accelerated expansion phase, with a period of decelerated expansion in between. This suggests that quantum gravitational effects can influence most of the history or even the entire history of the Universe.

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BibTeXRIS

Edésio M. Barboza Jr., Nivaldo A. Lemos. 2008-05-26. Can Quantum Gravitational Effects Influence the Entire History of the Universe?. https://doi.org/10.1103/physrevd.78.023504

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