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Non-Perturbative Formulation of Time-Dependent String Solutions

Jean Alexandre·John Ellis·Nikolaos E. Mavromatos
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Abstract

We formulate here a new world-sheet renormalization-group technique for the bosonic string, which is non-perturbative in the Regge slope alpha' and based on a functional method for controlling the quantum fluctuations, whose magnitudes are scaled by the value of alpha'. Using this technique we exhibit, in addition to the well-known linear-dilaton cosmology, a new, non-perturbative time-dependent background solution. Using the reparametrization invariance of the string S-matrix, we demonstrate that this solution is conformally invariant to alpha', and we give a heuristic inductive argument that conformal invariance can be maintained to all orders in alpha'. This new time-dependent string solution may be applicable to primordial cosmology or to the exit from linear-dilaton cosmology at large times.

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Jean Alexandre, John Ellis, Nikolaos E. Mavromatos. 2006-10-06. Non-Perturbative Formulation of Time-Dependent String Solutions. https://doi.org/10.1088/1126-6708%2F2006%2F12%2F071

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