Triangle Seminars
Tuesday, 13 Jan 2026
TBA
๐ London
Aron Wall
(University of Cambridge)
Abstract:
TBA
TBA
Posted by: Sebastian Cespedes
Wednesday, 14 Jan 2026
Solving the AdS3/CFT2 duality
๐ London
Alessandro Sfondrini
(Birmingham University)
Abstract:
The correspondence between strings on AdS3 and dual CFT2s is one of the cornerstones of holography since its very inception. In the last few years there has been a remarkable revival of activity and progress in understanding quantitatively (i.e., solving) this duality. In this blackboard talk, I will present a pedagogical review of this progress and point out the exciting challenges which lie ahead.
Reference literature: A recent review of the subject can be found in arXiv:2408.08414
The correspondence between strings on AdS3 and dual CFT2s is one of the cornerstones of holography since its very inception. In the last few years there has been a remarkable revival of activity and progress in understanding quantitatively (i.e., solving) this duality. In this blackboard talk, I will present a pedagogical review of this progress and point out the exciting challenges which lie ahead.
Reference literature: A recent review of the subject can be found in arXiv:2408.08414
Posted by: Jesse van Muiden
Thursday, 15 Jan 2026
Automorphic L-functions, primon gases and quantum cosmology
๐ London
Sean A. Hartnoll
(Cambridge U., DAMTP)
Abstract:
I will review how the equations of general relativity near a spacetime singularity map onto an arithmetic hyperbolic billiard dynamics. The semiclassical quantum states for this dynamics are Maaฮฒ cusp forms on fundamental domains of modular groups. For example, gravity in four spacetime dimensions leads to PSL(2,Z) while five dimensional gravity leads to PSL(2,Z[w]), with Z[w] the Eisenstein integers. The automorphic forms can be expressed, in a dilatation (Mellin transformed) basis as L-functions. The Euler product representation of these L-functions indicates that these quantum states admit a dual interpretation as a "primon gas" partition function. I will describe some physically motivated mathematical questions that arise from these observations.
I will review how the equations of general relativity near a spacetime singularity map onto an arithmetic hyperbolic billiard dynamics. The semiclassical quantum states for this dynamics are Maaฮฒ cusp forms on fundamental domains of modular groups. For example, gravity in four spacetime dimensions leads to PSL(2,Z) while five dimensional gravity leads to PSL(2,Z[w]), with Z[w] the Eisenstein integers. The automorphic forms can be expressed, in a dilatation (Mellin transformed) basis as L-functions. The Euler product representation of these L-functions indicates that these quantum states admit a dual interpretation as a "primon gas" partition function. I will describe some physically motivated mathematical questions that arise from these observations.
Posted by: Morteza S. Hosseini