Title: Pseudo-gauge ambiguity of the mechanical properties inside a nucleon
Date: Oct 30, 2025
Time: 14:00 - 15:00
Speaker: Mr. Tomoya Uji
Affiliation: University of Tokyo
Abstract: Motivated by the upcoming EIC experiment, the internal structure of a nucleon has drawn much attention recently. In particular, numerous attempts have been made to determine the D-form factor. The D-form factor governs the spatial components of the energy–momentum tensor (EMT) and is therefore expected to encode the pressure and shear-force distributions inside the nucleon. However, the EMT is not unique owing to the pseudo-gauge ambiguity. Therefore, some quantities that are defined by the EMT, such as the energy density, the pressure, and the shear force, can be pseudo-gauge dependent. Given this context, we explicitly calculated the two different types of EMT, i.e., the canonical EMT and the Belinfante EMT, in the two-flavor Skyrme model with vector mesons. In this talk, we show the behavior of the resulting mechanical profiles and clarify which quantities depend on the pseudo-gauge choice and which do not.