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arXiv · hep-th/9212016

On the spectrum, no ghost theorem and modular invariance of $W_3$ strings

Peter West
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Abstract

A spectrum generating algebra is constructed and used to find all the physical states of the $W_3$ string with standard ghost number. These states are shown to have positive norm and their partition function is found to involve the Ising model characters corresponding to the weights 0 and 1/16. The theory is found to be modular invariant if , in addition, one includes states that correspond to the Ising character of weight 1/2. It is shown that these additional states are indeed contained in the cohomology of $Q$.

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Peter West. 1992-12-02. On the spectrum, no ghost theorem and modular invariance of $W_3$ strings. https://doi.org/10.1142/s0217751x93001168

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