Tachyon condensation and universality of DBI action

We show that a low-energy action for massless fluctuations around a tachyonic soliton background representing a codimension one D-brane coincides with the Dirac-Born-Infeld action. The scalar modes which describe transverse oscillations of the D-brane are translational collective coordinates of the soliton. The appearance of the DBI action is a universal feature independent of details of a tachyon effective action, provided it has the structure implied by the open string sigma model partition function.

我们表明，在代表余维为一的D - 膜的快子孤子背景周围的无质量涨落的低能作用与狄拉克 - 玻恩 - 英费尔德作用一致。描述D - 膜横向振动的标量模式是孤子的平移集体坐标。只要快子有效作用具有由开弦西格玛模型配分函数所暗示的结构，狄拉克 - 玻恩 - 英费尔德作用的出现就是一个与快子有效作用的细节无关的普遍特征。