# Many-Body Scars as a Group Invariant Sector of Hilbert Space.

@article{Pakrouski2020ManyBodySA,
title={Many-Body Scars as a Group Invariant Sector of Hilbert Space.},
author={Kiryl Pakrouski and Preethi N. Pallegar and Fedor K. Popov and Igor R. Klebanov},
journal={Physical review letters},
year={2020},
volume={125 23},
pages={
230602
}
}
We present a class of Hamiltonians H for which a sector of the Hilbert space invariant under a Lie group G, which is not a symmetry of H, possesses the essential properties of many-body scar states. These include the absence of thermalization and the "revivals" of special initial states in time evolution. A particular class of examples concerns interacting spin-1/2 fermions on a lattice consisting of N sites (it includes deformations of the Fermi-Hubbard model as special cases), and we show…

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