Positivity of Curvature-Squared Corrections in Gravity
نویسندگان
چکیده
منابع مشابه
Positivity of Curvature-Squared Corrections in Gravity.
We study the Gauss-Bonnet (GB) term as the leading higher-curvature correction to pure Einstein gravity. Assuming a tree-level ultraviolet completion free of ghosts or tachyons, we prove that the GB term has a nonnegative coefficient in dimensions greater than 4. Our result follows from unitarity of the spectral representation for a general ultraviolet completion of the GB term.
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2017
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.118.051601