Speaker
Description
The Energy Mover's Distance (EMD) has seen use in collider physics as a metric between events and as a geometric method for defining IRC-safe observables. Recently, the spectral EMD (SEMD) has been proposed as a more analytically tractable alternative to the EMD. In this work, we obtain a closed-form expression for the $p = 2$ SEMD metric between events, removing the need to numerically solve an optimal transport problem. Additionally, we show how the SEMD can be used to define event and jet shape observables by minimizing the metric between events and parameterized energy flows (similar to the EMD), and we obtain closed-form expressions for several of these observables. We present this as part of the SPECTER framework, an efficient and highly parallelized implementation of the SEMD metric and SEMD-derived shape observables that offers a significant speedup compared to traditional optimal transport methods.
