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arXiv · 1810.02236

One-loop bosonic string and De Sitter space

Sabine Harribey·Dimitrios Tsimpis
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Abstract

We calculate the bosonic string one-loop three- and four-point amplitudes to quadradic order in momentum, and we read off the one-loop low-energy two-derivative effective action for the massless fields, $S_{eff}$. Treating the renormalized one-loop vacuum energy as a tunable parameter and extrapolating to a supercritical dimension $D > 26$, one can reach a regime where the one-loop couplings in Seff are of the same order as the tree-level ones while all higher-loop corrections are negligible. Moreover the effective spacetime curvature is small in string units. We show that the effective action thus obtained admits weakly-curved de Sitter solutions with constant dilaton at small string coupling.

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Sabine Harribey, Dimitrios Tsimpis. 2019-09-25. One-loop bosonic string and De Sitter space. https://doi.org/10.1016/j.nuclphysb.2019.114768

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