Events

Date: 11 December 2025   Time: 14:00 - 15:00

Location: Room 610, G.O. Jones Building

One Constant to Rule Them All

The SU(N) theory with 2N fundamental matter multiplets, in the vicinity of the so-called special vacuum - where the vacuum expectation values of the Higgs field are arranged near the vertices of a regular N-gon - is known to possess ⌊N/2⌋ effective coupling constants. I will show, however, that with the diameter of the polygon tending to infinity, a single effective coupling constant emerges. Moreover, this unique effective coupling enters the Zamolodchikov-like recurrence relation for the instanton partition function that remains valid for arbitrary vacuum expectation values, and is therefore meaningful beyond the special vacuum. By reconstructing the coupling matrix with simple symmetry and dimensional arguments, I will clarify the origin of this unique effective coupling. Finally, I will present the complete set of ⌊N/2⌋ effective couplings and discuss their modular properties, as well as the corrections induced by the masses of the matter multiplets.