# Exactly Solvable Lattice Hamiltonians and Gravitational Anomalies

@inproceedings{Chen2021ExactlySL, title={Exactly Solvable Lattice Hamiltonians and Gravitational Anomalies}, author={Yu-An Chen and Po-Shen Hsin}, year={2021} }

We construct infinitely many new exactly solvable local commuting projector lattice Hamiltonian models for general bosonic beyond group cohomology invertible topological phases of order two and four in any spacetime dimensions, whose boundaries are characterized by gravitational anomalies. Examples include the beyond group cohomology invertible phase without symmetry in (4+1)D that has an anomalous boundary Z2 topological order with fermionic particle and fermionic loop excitations that have…

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