# Second law of quantum complexity

@article{Brown2018SecondLO, title={Second law of quantum complexity}, author={Adam R. Brown and Leonard Susskind}, journal={Physical Review D}, year={2018}, volume={97}, pages={086015} }

We give arguments for the existence of a thermodynamics of quantum complexity that includes a “second law of complexity.” To guide us, we derive a correspondence between the computational (circuit) complexity of a quantum system of K qubits, and the positional entropy of a related classical system with 2K degrees of freedom. We also argue that the kinetic entropy of the classical system is equivalent to the Kolmogorov complexity of the quantum Hamiltonian. We observe that the expected pattern…

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