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Shao, Shu -Heng

Publications and source records attributed to Shao, Shu -Heng.

(2, 2) superconformal bootstrap in two dimensions

We find a simple relation between two-dimensional BPS N = 2 superconformal blocks and bosonic Virasoro conformal blocks, which allows us to analyze the crossing equations for BPS 4-point functions in unitary (2, 2) superconformal theories numerically with semidefinite programming. Here, we constrain gaps in the non-BPS spectrum through the operator product expansion of BPS operators, in ways that depend on the moduli of exactly marginal deformations through chiral ring coefficients. In some cases, our bounds on the spectral gaps are observed to be saturated by free theories, by N = 2 Liouville theory, and by certain Landau-Ginzburg models.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Higher derivative couplings in theories with sixteen supersymmetries

We give simple arguments for new non-renormalization theorems on higher derivative couplings of gauge theories to supergravity, with sixteen supersymmetries, by considerations of brane-bulk superamplitudes. This leads to some exact results on the effective coupling of D3-branes in type IIB string theory. As a result, we also derive exact results on higher dimensional operators in the torus compactification of the six dimensional (0, 2) superconformal theory.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Interpolating the Coulomb phase of little string theory

We study up to 8-derivative terms in the Coulomb branch effective action of (1,1) little string theory, by collecting results of 4-gluon scattering amplitudes from both perturbative 6D super-Yang-Mills theory up to 4-loop order, and tree-level double scaled little string theory (DSLST). In previous work we have matched the 6-derivative term from the 6D gauge theory to DSLST, indicating that this term is protected on the entire Coulomb branch. The 8-derivative term, on the other hand, is unprotected. In this paper we compute the 8-derivative term by interpolating from the two limits, near the origin and near the infinity on the Coulomb branch, numerically from SU(k) SYM and DSLST respectively, for k=2,3,4,5. We discuss the implication of this result on the UV completion of 6D SYM as well as the strong coupling completion of DSLST. As a result, we also comment on analogous interpolating functions in the Coulomb phase of circle-compactified (2,0) little string theory.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗