A note on gauge-covariant vertex operators of the ambitwistor string

Osvaldo Chandia

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arXiv · 2609.27026

A note on gauge-covariant vertex operators of the ambitwistor string

Osvaldo Chandia

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Abstract

We construct gauge-covariant unintegrated vertex operators in an antighost-independent subcomplex of the bosonic ambitwistor string. For a linearized gauge field, a world-sheet ghost-derivative term completes the standard vertex so that BRST closure imposes $\p^nF_{nmI}=0$ without the Lorenz condition. In the rank-two sector we use an antighost-free ansatz that is sufficient to isolate a diffeomorphism-invariant spin-two subsector. After eliminating auxiliary fields and consistently setting the antisymmetric and scalar combinations to zero, BRST closure gives $R_{mn}=0$ without imposing transversality. We distinguish this construction from the full relative BRST cohomology of the bosonic ambitwistor string, whose additional antighost-dependent states lead to the known higher-derivative spectrum.

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Osvaldo Chandia. 2026-09-22. A note on gauge-covariant vertex operators of the ambitwistor string. https://arxiv.org/abs/2609.27026

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