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Higher Level Open String States from Vacuum String Field Theory

Hiroyuki Hata·Hisashi Kogetsu
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Abstract

We construct massive open string states around a classical solution in the oscillator formulation of Vacuum String Field Theory. In order for the correct mass spectrum to be reproduced, the projection operators onto the modes of the left- and right-half of the string must have an anomalous eigenvalue 1/2, and the massive states are constructed using the corresponding eigenvector. We analyze numerically the projection operators by regularizing them to finite size matrices and confirm that they indeed have eigenvalue 1/2. Beside the desired massive states, we have spurious massive as well as massless states, which are infinitely degenerate. We show that these unwanted states can be gauged away.

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Hiroyuki Hata, Hisashi Kogetsu. 2002-08-27. Higher Level Open String States from Vacuum String Field Theory. https://doi.org/10.1088/1126-6708%2F2002%2F09%2F027

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