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arXiv · 2606.24859

Additional constraints for the tensor bootstrap

Samuel Laliberte·Reiko Toriumi
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Abstract

Recently, new positivity constraints were suggested to constrain arbitrary unitary tensor integrals. In the present work, we explore two variants of these positivity constraints: one built from ``open bubbles'', which are tensor-like objects found by removing a tensor from a bubble invariant, and the second built from ``color matrices'', which are matrices found by removing a color contraction from a bubble invariant. Using these positivity constraints, we find sharp bounds on unitary tensor integrals at finite $N$, and probe deviations from Gaussian universality in this limit.

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Samuel Laliberte, Reiko Toriumi. 2026-06-23. Additional constraints for the tensor bootstrap. https://arxiv.org/abs/2606.24859

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