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  Open string amplitude with higher vertices

+ 2 like - 0 dislike

In Polchinski's String Theory, section 6.2, the tree level amplitude for open strings with higher vertices are given (6.2.18-20).

The amplitude

$\langle \prod_i[e^{ik_i\cdot X(z_i,\bar {z_i})}]_r\prod_j\partial X^{\mu_j}(z_j')\prod_k\bar \partial X^{\nu_k}(\bar z_k'')\rangle$

yields result

$\text{other terms }\times \langle\prod_j[v^{\mu_j}+q^{\mu_j}]\prod_k[\tilde v^{\mu_k}+\tilde q^{\mu_k}]\rangle$

However I could not repeat the calculation there. To be specific, I don't know what source term $J$ corresponds to the $\partial X^\mu$ terms in the amplitude. Could you help me with this or point out some notes with more detailed calculation?

asked Apr 21, 2014 in Theoretical Physics by Han Yan (110 points) [ revision history ]
edited Apr 21, 2014 by dimension10

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