On Multibrane Solutions in Open String Field Theory

The classical solutions of open string field theory are solitonic extended objects whose fluctuation spectra are described by open strings. At the turn of the millennium, Ashoke Sen discovered that tachyonic modes lead to instabilities of these solitionic objects and that there are classical solutions describing various endpoints with the expected properties, and among them a solution with no soliton. A group of researchers at MIT speculated that reverse phenomenon might occur, namely that there can be classical solutions describing multiple xerox copies of the original soliton. In this paper, first strong evidence for such a speculation was provided by constructing analytic solution with the desired properties. The result sheds a new light on why there is a color, i.e. non-abelian gauge symmetry, in particle physics.

M. Murata. M. Schnabl, Prog.Theor.Phys.Suppl. 188 (2011) 50-55; JHEP 1207 (2012) 063.