标题： 树级开弦振幅的递归关系的一般表达式 显示英文标题

标题： General Expressions for On-shell Recursion relations for Tree-level Open String Amplitudes

摘要： 本文中，我们系统地推导出旨在获得树级开弦振幅的递归关系通表达式。 我们的方法涉及将BCFW位移应用于用多重高斯超几何函数表示的开弦振幅。 通过采用二项式展开，我们证明了位移后的振幅表现出简单极点，这些极点对应于中间态的散射道。 利用留数定理，我们由此得出这些关系的通表达式。 显示英文摘要

摘要： In this paper, we present a systematic derivation aimed at obtaining general expressions for on-shell recursion relations for tree-level open string amplitudes. Our approach involves applying the BCFW shift to an open string amplitude written in terms of multiple Gaussian hypergeometric functions. By employing binomial expansions, we demonstrate that the shifted amplitudes manifest simple poles, which correspond to scattering channels of intermediate states. Using the residue theorem, we thereby derive a general expression for these relations.