Thermo field dynamics on a quantum computer

Thermofield dynamics: Quantum Chaos versus Decoherence

“…It could be probed via the quantum simulation of the SYK Hamiltonian [42][43][44][45] but it is generally expected in an arbitrary quantum chaotic system. While the preparation of the TFD state is being pursued [62][63][64][65] this requirement can be relaxed for the study of some observables, such as the fidelity of a TFD state, as its expectation value can be related to that of a coherent Gibbs state |ψ β = n e −βEn/2 |n / Z(β) involving a single copy of the system. Indeed, under unitary time evolution…”