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Effective Nonlocal Euclidean Gravity

C. Wetterich
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Abstract

A nonlocal form of the effective gravitational action could cure the unboundedness of euclidean gravity with Einstein action. On sub-horizon length scales the modified gravitational field equations seem compatible with all present tests of general relativity and post-Newtonian gravity. They induce a difference in the effective Newton's constant between regions of space with vanishing or nonvanishing curvature scalar (or Ricci tensor). In cosmology they may lead to a value $Ω<1$ for the critical density after inflation. The simplest model considered here appears to be in conflict with nucleosynthesis, but generalizations consistent with all cosmological observations seem conceivable.

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C. Wetterich. 1997-04-18. Effective Nonlocal Euclidean Gravity. https://doi.org/10.1023/a%3A1018837319976

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