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Spikes in Quantum Regge Calculus

J. Ambjorn·J. Nielsen·J. Rolf·G. Savvidy
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Abstract

We demonstrate by explicit calculation of the DeWitt-like measure in two-dimensional quantum Regge gravity that it is highly non-local and that the average values of link lengths $l, $, do not exist for sufficient high powers of $n$. Thus the concept of length has no natural definition in this formalism and a generic manifold degenerates into spikes. This might explain the failure of quantum Regge calculus to reproduce the continuum results of two-dimensional quantum gravity. It points to severe problems for the Regge approach in higher dimensions.

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J. Ambjorn, J. Nielsen, J. Rolf, G. Savvidy. 1997-04-28. Spikes in Quantum Regge Calculus. https://doi.org/10.1088/0264-9381%2F14%2F12%2F009

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