# Non-ergodic dynamics in SU(2) lattice gauge theory: scars, fragmentation, and disorder-free localization

- Institution: CERN
- Speaker: Giovanni Cataldi
- Year: 2026
- Language: English
- Source: [CERN](https://videos.cern.ch/record/3025647)
- Licence: [CERN](https://copyright.web.cern)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

Non-Abelian lattice gauge theories provide a setting where local constraints reshape far-from-equilibrium quantum many-body dynamics and can obstruct thermalization. In a (1+1)D SU(2) lattice gauge theory with dynamical matter, three non-ergodic phenomena are identified, each with a different origin. In regimes where the gauge-invariant dynamics is otherwise ergodic, low-overhead product-state quenches exhibit robust quantum many-body scarring, seen as long-lived coherent oscillations in local observables and pronounced fidelity revivals enabled by non-Abelian meson and baryon–antibaryon excitations. In a separate region of parameters, the gauge-invariant model becomes nonthermal yet delocalized due to Hilbert-space fragmentation into disconnected Krylov subsectors. Finally, when static SU(2) background charges are introduced to encode gauge superselection sectors, and the system is initialized in a coherent superposition of these sectors, disorder-free localization emerges even where a fixed sector is ergodic: spatial matter inhomogeneities persist at long times, and entanglement exhibits MBL-like (logarithmic) growth. These results provide a unified benchmark suite for non-ergodic far-from-equilibrium dynamics in non-Abelian constrained systems and are compatible with digital quantum simulation on existing qudit platforms.

00:00:00 Slide 1

00:00:25 Slide 2

00:01:17 Slide 3

00:02:25 Slide 4

00:04:12 Slide 5

00:06:51 Slide 6

00:10:14 Slide 7

00:12:42 Slide 8

00:15:03 Slide 9

00:17:31 Slide 10

00:19:16 Slide 11

00:23:40 Slide 12

00:25:28 Slide 13

00:27:00 Slide 14

00:27:48 Slide 15

00:28:25 Slide 16

00:29:17 Slide 17

00:30:55 Slide 18

00:32:28 Slide 19

00:33:36 Slide 20

00:34:13 Slide 21

00:36:23 Slide 22

00:37:54 Slide 23

00:38:30 Slide 24

00:38:55 Slide 25

00:40:01 Slide 26

00:44:07 Slide 27

00:45:39 Slide 28

00:47:09 Slide 29

00:48:54 Slide 30

00:49:12 Slide 31

00:51:28 Slide 32

00:52:24 Slide 33

00:53:38 Slide 34

00:54:31…

## Lectures

1. [Non-ergodic dynamics in SU(2) lattice gauge theory: scars, fragmentation, and disorder-free localization](https://invisiblenetwork.ai/learn/cern/3025647/f52a7ea78047), 1 h 6 min (CERN's player)