# Symbol Alphabets from the Landau Singular Locus

- Institution: CERN
- Department: Conferences, Workshops & Schools
- Speaker: Christoph Dlapa
- Year: 2023
- Language: English
- Source: [CERN](https://videos.cern.ch/record/2302573)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

I present work which provides evidence through two loops that rational letters of polylogarithmic Feynman integrals are captured by the Landau equations, when the latter are recast as a polynomial of the kinematic variables of the integral, known as the principal A-determinant. Focusing on one loop, I further discuss how all square-root letters may also be obtained, by re-factorizing the principal A-determinant with the help of Jacobi identities. The letters are verified by explicitly constructing canonical differential equations for the one-loop integrals in both odd and even dimensions of loop momenta..

0:00:00 Slide 1

0:03:03 Slide 2

0:05:01 Slide 3

0:08:01 Slide 4

0:09:30 Slide 5

0:11:19 Slide 6

0:13:15 Slide 7

0:15:22 Slide 8

0:17:21 Slide 9

0:19:35 Slide 10

0:21:09 Slide 11

0:22:26 Slide 12

0:26:57 Slide 13

0:28:02 Slide 14

0:30:13 Slide 15

## Lectures

1. [Symbol Alphabets from the Landau Singular Locus](https://invisiblenetwork.ai/learn/cern/2302573/c40ffb48f792), 33 min (CERN's player)