aiqbench analysis
This research investigates the entanglement Hamiltonian in infinite hopping chains following partial projective measurements, revealing how local inverse temperature and chemical potential encode specific information about measurement outcomes via conformal mappings. The study highlights a fundamental distinction where post-selected states retain detailed outcome data beyond what entropy alone can provide, advancing theoretical understanding of quantum many-body systems under observation.
Measurement-induced entanglement Hamiltonian
arXiv:2608.06006v1 Announce Type: cross Abstract: We study the entanglement Hamiltonian of an infinite hopping chain in its ground state, after partial projective measurements in the occupation basis. For a segment separated by two measurement regions from the rest of the chain, we show that the reduced density matrix can be related to a grand-canonical state via a conformal mapping and a gauge transformation in the underlying field-theory description. The entanglement Hamiltonian is then described by a local inverse temperature that vanishes as a square root around the endpoints and is independent of the particular measurement outcome. In sharp contrast, the local chemical potential is shown to be related to the induced charge density in the segment. Hence the entanglement Hamiltonian of a post-selected state contains much more information on the measurement outcome than the respective entropy.
Abstract:We study the entanglement Hamiltonian of an infinite hopping chain in its ground state, after partial projective measurements in the occupation basis. For a segment separated by two measurement regions from the rest of the chain, we show that the reduced density matrix can be related to a grand-canonical state via a conformal mapping and a gauge transformation in the underlying field-theory description. The entanglement Hamiltonian is then described by a local inverse temperature that vanishes as a square root around the endpoints and is independent of the particular measurement outcome. In sharp contrast, the local chemical potential is shown to be related to the induced charge density in the segment. Hence the entanglement Hamiltonian of a post-selected state contains much more information on the measurement outcome than the respective entropy.
Statistical Mechanics (cond-mat.stat-mech); High Energy Physics - Theory (hep-th); Quantum Physics (quant-ph)
arXiv:2608.06006 [cond-mat.stat-mech]
(or arXiv:2608.06006v1 [cond-mat.stat-mech] for this version)
https://doi.org/10.48550/arXiv.2608.06006 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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Full text under the publisher's open licence · 234 words
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