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arXiv · 2606.17602

Lorentzian Regularization of the Type IIB Superstring Torus Vacuum

Thomas Junkai Wang
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Abstract

We study the one-loop torus vacuum of Type IIB Superstring theory through sector-resolved modular integrals. Building on the i\varepsilon-prescription and the E_s-regularized modular-integral framework of Manschot and Wang [1], we construct regularized sector functionals for the closed oriented torus before the final GSO projection. The construction keeps the unprojected spin-sector data explicit and fixes the compact-domain and cusp contributions within a single modular prescription. We also independently cross-check the result with the Lorentzian-inversion reconstruction of modular integrals by Baccianti et al. [2] This provides a first direct regularized construction of the unprojected sectors of the Type IIB Superstring torus vacuum.

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Thomas Junkai Wang. 2026-06-16. Lorentzian Regularization of the Type IIB Superstring Torus Vacuum. https://arxiv.org/abs/2606.17602

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