Rolling near the tachyon vacuum

摘要

A bstract In a linear dilaton background, it has been argued that an unstable D-brane can decay to the tachyon vacuum without leaving behind a remnant of tachyon matter. Here we address the question of how the D-brane can decay to the tachyon vacuum when the tachyon vacuum does not support physical fluctuations. Using the formalism of open string field theory, we find that the tachyon vacuum can support fluctuations provided they are “hidden” as nonperturbative effects behind a pure gauge asymptotic series.