  We discuss novel properties of the string field and the Open String Field
Theory action arising in a system with multiple D-branes, then use the level
truncation scheme to study marginal deformations and tachyon condensation in a
system with two parallel but separated branes. We find string fields
corresponding to D-brane decay combined with a finite change in the distance
between the two D-branes. Using D-brane separation as a yardstick, we are able
to continuously control the spacetime displacement of the D-branes and find
that our solutions exist only for a finite range of this displacement. Thus, at
least in level truncation, Open String Field Theory seems unable to describe
the entire CFT moduli space.

High Energy Physics - Theory