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arXiv · hep-th/9501049

Scaling in quantum gravity

J. Ambjorn·Y. Watabiki
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Abstract

The 2-point function is the natural object in quantum gravity for extracting critical behavior: The exponential fall off of the 2-point function with geodesic distance determines the fractal dimension $d_H$ of space-time. The integral of the 2-point function determines the entropy exponent $γ$, i.e. the fractal structure related to baby universes, while the short distance behavior of the 2-point function connects $γ$ and $d_H$ by a quantum gravity version of Fisher's scaling relation. We verify this behavior in the case of 2d gravity by explicit calculation.

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J. Ambjorn, Y. Watabiki. 1995-01-13. Scaling in quantum gravity. https://doi.org/10.1016/0550-3213(95)00154-k

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