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arXiv · 0802.4395

Nonlocal instantons and solitons in string models

Gianluca Calcagni·Giuseppe Nardelli
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Abstract

We study a class of nonlocal systems which can be described by a local scalar field diffusing in an auxiliary radial dimension. As examples p-adic, open and boundary string field theory are considered on Minkowski, Friedmann-Robertson-Walker and Euclidean metric backgrounds. Starting from distribution-like initial field configurations which are constant almost everywhere, we construct exact and approximate nonlocal solutions. The Euclidean p-adic lump is interpreted as a solitonic brane, and the Euclidean kink of supersymmetric open string field theory as an instanton. Some relations between solutions of different string theories are highlighted also thanks to a reformulation of nonlocal systems as fixed points in a renormalization group flow.

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BibTeXRIS

Gianluca Calcagni, Giuseppe Nardelli. 2008-10-02. Nonlocal instantons and solitons in string models. https://doi.org/10.1016/j.physletb.2008.09.016

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