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arXiv · 0712.0627

Linear b-Gauges for Open String Fields

Michael Kiermaier·Ashoke Sen·Barton Zwiebach
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Abstract

Motivated by Schnabl's gauge choice, we explore open string perturbation theory in gauges where a linear combination of antighost oscillators annihilates the string field. We find that in these linear b-gauges different gauge conditions are needed at different ghost numbers. We derive the full propagator and prove the formal properties which guarantee that the Feynman diagrams reproduce the correct on-shell amplitudes. We find that these properties can fail due to the need to regularize the propagator, and identify a large class of linear b-gauges for which they hold rigorously. In these gauges the propagator has a non-anomalous Schwinger representation and builds Riemann surfaces by adding strip-like domains. Projector-based gauges, like Schnabl's, are not in this class of gauges but we construct a family of regular linear b-gauges which interpolate between Siegel gauge and Schnabl gauge.

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Michael Kiermaier, Ashoke Sen, Barton Zwiebach. 2007-12-05. Linear b-Gauges for Open String Fields. https://doi.org/10.1088/1126-6708%2F2008%2F03%2F050

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