Robust Hilbert space fragmentation in group-valued loop models

• URL: http://arxiv.org/abs/2406.19386v2
• Date: Tue, 2 Jul 2024 19:04:09 GMT
• Title: Robust Hilbert space fragmentation in group-valued loop models
• Authors: Alexey Khudorozhkov, Charles Stahl, Oliver Hart, Rahul Nandkishore,
• Abstract summary: We introduce a large class of models exhibiting robust ergodicity breaking in quantum dynamics. Our work is inspired by recent discussions of "topologically robust space fragmentation" We make crisp connections to gauge theories, and our construction generalizes Kitaev's quantum double to infinite groups.
• Score: 0.32834134397982795
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We introduce a large class of models exhibiting robust ergodicity breaking in quantum dynamics. Our work is inspired by recent discussions of "topologically robust Hilbert space fragmentation," but massively generalizes in two directions: firstly from states describable as "loop-soups" to a broader class of states reminiscent of string-nets and sponges, and secondly from models restricted to square or cubic lattices, to models defined on arbitrary lattices (and even arbitrary graphs without translation invariance). Our constructions leverage a recently proposed group-theory framework [PRX 14, 021034 (2024)], and identify a host of new phenomena arising from the interplay of "group-model dynamics" and lattice structure. We make crisp connections to gauge theories, and our construction generalizes Kitaev's quantum double to infinite groups.

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