LoopFest XXIV

Toward an All-order Understanding of Region Structures

27 May 2026, 16:40

20m

Physics Department (Bldg. 510), Large Seminar Room (Brookhaven National Laboratory)

Parallel Session

Speaker

Yao Ma (ETH Zurich)

Description

The expansion-by-regions technique is a powerful tool for analyzing the asymptotic behavior of Feynman integrals, and the first critical step is to identify all relevant regions. In Euclidean kinematics, this has been understood to all orders, formulated as an "expansion-by-subgraphs" procedure. In Minkowski kinematics, however, the situation is much more subtle.

Much progress has been made in recent years. Regions have been classified as "facet regions" and "hidden regions", and this talk will summarize the state-of-the-art understanding of their structures. In particular, a recent work 2601.22144 will be highlighted, where an all-order prescription has been given for facet regions of any massless graph in the wide-angle kinematics.