Monday, October 7, 2024

Hjalmar Rosengren (Chalmars) -- Thursday, Oct 10, 2024, 4:00 PM IST (12:30 PM CEST)

 Dear all,


Our talk this week is by Hjalmar Rosengren (Chalmers). Here is the announcement.

Talk Announcement: 

Title:  
String amplitudes and partial fractions: A mathematician's perspective
Speaker:  Hjalmar Rosengren (Chalmers University of Technology and University of Gothenburg)
When: Oct 10, 2024, 4:00 PM- 5:00 PM IST/ 12:30 PM (CEST)

Where: Zoom: Zoom


Abstract:
Using physics methods, Saha and Sinha recently obtained many intriguing expansions of string amplitudes (see Sinha's talk in this seminar 3 October). From a mathematical perspective, they are very unusual deformations of classical hypergeometric identities. One very special case gives a deformation of Madhava's famous series for pi, which received a lot of media attention. I will discuss these identities from a mathematical perspective. They can be derived from partial fraction expansions for symmetric rational functions, which may have some independent interest. 

The talk is based on the preprint https://arxiv.org/abs/2409.06658


Best wishes,

Gaurav Bhatnagar, Atul Dixit and Krishnan Rajkumar (organisers)

Thursday, October 3, 2024

Aninda Sinha (IISc, Bangalore) -- Thursday, Oct 3, 2024, 4:00 PM IST


Dear all,

We are back to our usual time with a talk by Aninda Sinha of IISc, Bangalore. 

Next week (on Oct 10), we will have a follow-up talk by Hjalmar Rosengren on the topic: String amplitudes and partial fractions: A mathematician's perspective. The formal announcement will be made on the weekend. But please mark your calendars. 


Talk Announcement: 

Title:  
Field theory expansions of string theory amplitudes
Speaker:  Aninda Sinha (Indian Institute of Science, Bangalore)
When: Oct 3, 2024, 4:00 PM- 5:00 PM IST 


Abstract:

This talk is based on: Phys. Rev. Lett. 132 (2024) 22, 221601 (e-print: 2401.05733 [hep-th])

I will explain the reasons (both physics and maths) for trying to find a new formula, satisfying certain physics inspired criteria, for the Euler-Beta and related functions. I will give a sketch of the derivation which relies on a novel dispersion relation. Towards the end, time permitting, new results from the Bootstrap will be presented. 


Best wishes,

Gaurav Bhatnagar, Atul Dixit and Krishnan Rajkumar (organisers)