9:00-10:00 Kimyeong Lee
10:30-11:30 Zhenbin Yang
Lunch
1:00-2:00 Manki Kim
3:00-4:00 Shanming Ruan
Free Discussions
Speaker: Manki Kim
Title: Non-linear sigma model in string field theory
Abstract: I will describe how to construct data of the worldsheet CFT of the strings probing a curved background with a non-trivial topology in string field theory. As a simple application, I will describe how to use this result to compute the D-instanton superpotential and loop corrections to the Kahler potential in Calabi-Yau orientifold compactifications in the large volume limit.
Speaker: Kimyeong Lee
Title: Conformal Field Theories on Magic Triangle
Abstract: In a recent work with Kaiwen Sun, we complete the magic triangle of Lie algebra related to division algebras of real and complex numbers, quaternion and octonion by studying WZW model CFTs. Especially they obey magic quotient relation and magic bi-linear relations. From which we find 5 fundamental atomic theories and also an exact formula for the dimension and degeneracy of each primary operators.
Speaker: Zhenbin Yang
Title: Comments on the de Sitter double cone
Abstract: We study the double cone geometry proposed by Saad, Shenker, and Stanford in de Sitter space. We demonstrate that with the inclusion of static patch observers, the double cone leads to a linear ramp consistent with random matrix behavior. This ramp arises from the relative time shift between two clocks located in opposite static patches.
Speaker: Shanming Ruan
Title: The Finite Black Hole Interior in Quantum Gravity
Abstract: Quantum gravity faces deep tensions between the smooth geometry of classical spacetime and the discrete, finite nature of the quantum Hilbert space. One striking manifestation of this tension is the infinite size of a black hole’s interior. For an AdS black hole, the volume of its interior (the Einstein–Rosen bridge) increases almost linearly at late times. Motivated by the complexity = anything proposal, we introduce the spectral representation of infinite generating functions for both codimension-one and codimension-zero gravitational observables that probe the black hole interior. Their time evolution exhibits a characteristic slope–ramp–plateau structure, analogous to the spectral form factor in chaotic quantum systems. Upon incorporating quantum corrections from Euclidean wormholes, we find that holographic complexity measures obey a universal time evolution: they grow linearly for a long period and then saturate at a plateau at late times. We further show that this universal behaviour is governed by a specific pole structure and by spectral level repulsion, the hallmark of quantum chaos.
