Line Defects, Tropicalization, and Multi-Centered Quiver Quantum Mechanics

Understand

We study BPS line defects in N=2 supersymmetric four-dimensional field theories.

• We focus on theories of "quiver type," those for which the BPS particle spectrum can be computed using quiver quantum mechanics.
• For a wide class of models, the renormalization group flow between defects defined in the ultraviolet and in the infrared is bijective.
• Using this fact, we propose a way to compute the BPS Hilbert space of a defect defined in the ultraviolet, using only infrared data.