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arXiv · 1703.05382

Stability of the nonperturbative bosonic string vacuum

J. Ambjorn·Y. Makeenko
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Abstract

Quantization of the bosonic string around the classical, perturbative vacuum is not consistent for spacetime dimensions 2<d<26. Recently we have showed that at large d there is another so-called mean field vacuum. Here we extend this mean field calculation to finite d and show that the corresponding mean field vacuum is stable under quadratic fluctuations for 2<d<26. We point out the analogy with the two-dimensional O(N)-symmetric sigma-model, where the 1/N-vacuum is very close to the real vacuum state even for finite N, in contrast to the perturbative vacuum.

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J. Ambjorn, Y. Makeenko. 2017-03-15. Stability of the nonperturbative bosonic string vacuum. https://doi.org/10.1016/j.physletb.2017.05.021

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