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Non-Local Modification of Gravity and the Cosmological Constant Problem

Nima Arkani-Hamed·Savas Dimopoulos·Gia Dvali·Gregory Gabadadze
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Abstract

We propose a phenomenological approach to the cosmological constant problem based on generally covariant non-local and acausal modifications of four-dimensional gravity at enormous distances. The effective Newton constant becomes very small at large length scales, so that sources with immense wavelengths and periods -- such as the vacuum energy-- produce minuscule curvature. Conventional astrophysics, cosmology and standard inflationary scenaria are unaffected, as they involve shorter length scales. A new possibility emerges that inflation may ``self-terminate'' naturally by its own action of stretching wavelengths to enormous sizes. In a simple limit our proposal leads to a modification of Einstein's equation by a single additional term proportional to the average space-time curvature of the Universe. It may also have a qualitative connection with the dS/CFT conjecture.

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Nima Arkani-Hamed, Savas Dimopoulos, Gia Dvali, Gregory Gabadadze. 2002-09-26. Non-Local Modification of Gravity and the Cosmological Constant Problem. https://arxiv.org/abs/hep-th/0209227

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