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Divergence Cancellation and Loop Corrections in String Field Theory on a Plane Wave Background

Gianluca Grignani·Marta Orselli·Bojan Ramadanovic·Gordon W. Semenoff·Donovan Young
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Abstract

We investigate the one-loop energy shift E to certain two-impurity string states in light-cone string field theory on a plane wave background. We find that there exist logarithmic divergences in the sums over intermediate mode numbers which cancel between the cubic Hamiltonian and quartic ``contact term''. Analyzing the impurity non-conserving channel we find that the non-perturbative, order g_2^2 sqrt(lambda') contribution to E/mu predicted in hep-th/0211220 is in fact an artifact of these logarithmic divergences and vanishes with them, leaving an order g_2^2 lambda' contribution. Exploiting the supersymmetry algebra, we present a form for the energy shift which appears to be manifestly convergent and free of non-perturbative terms. We use this form to argue that E/mu receives order g_2^2 lambda' contributions at every order in intermediate state impurities.

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Gianluca Grignani, Marta Orselli, Bojan Ramadanovic, Gordon W. Semenoff, Donovan Young. 2005-08-23. Divergence Cancellation and Loop Corrections in String Field Theory on a Plane Wave Background. https://doi.org/10.1088/1126-6708%2F2005%2F12%2F017

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