Two-Dimensional Quantum Cosmology*
نویسنده
چکیده
Two-dimensional quantum gravity coupled to conformally invariant matter with central charge c > 25 has been proposed as a toy model for quantum gravity in higher dimensions. The associated “Wheeler-Dewitt equation” is non-linear and unstable to forming a condensate of baby universes. This will occur even in the classical c + co limit. Small fluctuations about this background describe the propagation of single universes and satisfy a more conventional linear WheelerDewitt equation. The resulting two-dimensional cosmology depends on details of the non-linear dynamics. In particular the existence of a large scale cosmological constant is determined by the behavior of a string theoretic tachyon potential near its minimum.
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