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No causal order and topological phases

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 نشر من قبل Sudipto Singha Roy
 تاريخ النشر 2021
  مجال البحث فيزياء
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We consider a topological Hamiltonian and establish a correspondence between its eigenstates and the resource for a causal order game introduced in Ref. [1], known as process matrix. We show that quantum correlations generated in the quantum many-body energy eigenstates of the model can mimic the statistics that can be obtained by exploiting different quantum measurements on the process matrix of the game. This provides an interpretation of the expectation values of the observables computed for the quantum many-body states in terms of success probabilities of the game. As a result, we show that the ground state of the model can be related to the optimal strategy of the causal order game. Along with this, we show that a correspondence between the considered topological quantum Hamiltonian and the causal order game can also be made by relating the behavior of topological order parameters characterizing different phases of the model with the different regions of the causal order game.

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