Thread by @fgrosshans

Now at #IWQNS, Kavan Modi from @MonashUni on Stochastic proceses and application to quantum networks
#LTQI

@MonashUni Kavan Modi: Classical stochastic processes can ofte be modelled by MArkov Chains, ore hidden markov chains, where the last n responses (n:= Markov order) are lumped together. #LTQI #IWQNS

@MonashUni Kavan Modi: What happens on quantum systems ? Like Biomolecule hit by a stream of laser pulses, or qubit modified by gates in presence of correlated environment. #LTQI #IWQNS

Kavan Modi: In quantum systems, measurements influence the system, and it hase to be taken into account. The process is modelled by alternating things we control ℳ_n (measurement, unitaries, suff in between) ant the U_n of the process itself.
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Kavan Modi: The part we do not control, comb shaped (quantum comp) can be described by a tensor. Processes can be mapped to states with tensor network reprensentation, where bond dimension is memory → measure of non-markovianity. #LTQI #IWQNS

Kavan Modi: Is there a Markov order ? Memory is either 0 or ∞ :-(
But it can be approximated :-)
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Kavan Modi tested the IBM computer with successive gates. Non-markovianity is seen, and can be dealt with
arxiv:1902.05223 arxiv.org/abs/1902.05223 arxiv:1902.07980 arxiv.org/abs/1902.07980
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