Time evolution viaS-branes

Abstract

Using S(pacelike)-branes defined through rolling tachyon solutions, we show how the dynamical formation of D(irichlet)-branes and strings in tachyon condensation can be understood. Specifically we present solutions of S-brane actions illustrating the classical confinement of electric and magnetic flux into fundamental strings and D-branes. The role of S-branes in string theory is further clarified and their RR charges are discussed. In addition, by examining "boosted" S-branes, we find what appears to be a surprising dual S-brane description of strings and D-branes, which also indicates that the critical electric field can be considered as a self-dual point in string theory. We also introduce new tachyonic S-branes as Euclidean counterparts to non-BPS branes.

Effects of brane-flux transition on black holes in string theory

“…Time evolution of the S(pacelike)-brane has already been considered for simpler setup [37,38]. It is of importance to study the dynamics of this transition from black hole into the RR flux.…”

D-branes in overcritical electric fields

“…The fact that the D25-brane becomes tachyonic has another manifestation in the superluminal velocity of the T-dual D24-brane [12]. Equivalently, this is known to be a (tilted) S-brane, a spacelike object which arises in the description of the standard D-brane decay via the rolling tachyon picture [2,3]. In particular, in [2] an effective action has been derived for S-branes, which turns out to be equal to the Dirac-Born-Infeld action times a factor i.…”

“…The sign of the "bare" squared mass term depending on the level n is always reversed in overcritical fields. 3 We remark that a possible interpretation of this change of signature from the point of view of the full target space could be ascribed to an interchange of the role of space and time between the directions 0 and 1. However, if one demands now x1 to assume the role of time, thus recovering a standard positive mass spectrum for the open string tower, then the closed string sector of the theory, whose masses are determined via the closed string metric as κµg µν κν = −4(n − 1), would have infinite tachyons.…”

“…From the open string point of view, the analogy with pair production of pointlike charges suggests that the endpoint of the condensation process corresponds to the discharge of the overcritical electric field: dipoles nucleating from the vacuum easily stretch to infinity until they screen the electric field making it critical or undercritical [3]. When looking at the D-brane decay, this means that the fluctuations around the unstable configuration are going to lower the value of the electric background itself towards critical or undercritical values.…”

“…Open strings in the presence of an overcritical electric field mainly have been considered as an ill-defined setting (there are however interesting connections with S-branes, see for instance [2,3]). Classically the endpoints of open strings have to move with superluminal velocity and at the quantum level there appears a singularity at the critical field strength in the string analog of the Schwinger pair creation [4,5].…”