3 papers
quant-ph2024
Exponential separation in quantum query complexity of the quantum switch with respect to simulations with standard quantum circuits
Hlér Kristjánsson, Tatsuki Odake, Satoshi Yoshida +4
Quantum theory is consistent with a computational model permitting black-box operations to be applied in an indefinite causal order, going beyond the standard circuit model of comp…
quant-ph2024
Simulating the quantum switch with quantum circuits is computationally hard
Jessica Bavaresco, Hlér Kristjánsson, Mio Murao +4
Higher-order transformations acting on input quantum channels in an indefinite causal order, such as the quantum switch, cannot be described by quantum circuits using the same numb…
quant-ph2024
Analytical Lower Bound on Query Complexity for Transformations of Unknown Unitary Operations
Tatsuki Odake, Satoshi Yoshida, Mio Murao
Recent developments have revealed deterministic and exact protocols for performing complex conjugation, inversion, and transposition of a general -dimensional unknown unitary op…