Shi-Lin Wan | Searcharxiv

arXiv2026

Analytic Bootstrap of the Veneziano Amplitude

We analytically prove that the Veneziano amplitude is the unique outcome of a dual bootstrap based on dispersive sum rules, unitarity, and a small amount of additional stringy input. This stringy input can be either the string monodromy condition or the recently uncovered splitting condition. A key ingredient in our proofs is to interpret the dispersive sum rules as sequences of moments. Also important is the precise incorporation of the extra stringy input into the amplitude ansatz. Together, these ingredients make the bootstrap analytically tractable and uniquely fix the Veneziano amplitude.

hep-th↗

arXiv2024

Matrix moment approach to positivity bounds and UV reconstruction from IR

Positivity bounds in effective field theories (EFTs) can be extracted through the moment problem approach, utilizing well-established results from the mathematical literature. We generalize this formalism using the matrix moment approach to derive positivity bounds for theories with multiple field components. The sufficient conditions for obtaining optimal bounds are identified and applied to several example field theories, yielding results that match precisely the numerical bounds computed using other methods. The upper unitarity bounds can also be easily harnessed in the matrix case. Furthermore, the moment problem formulation also provides a means to reverse engineer the UV spectrum from the EFT coefficients, often uniquely, as explicitly demonstrated in examples such as string amplitudes and the $stu$ kink theory.

hep-th↗