Until now, quantum communication protocols relied on an assumption about how channels combine, that averaging them always behaved predictably during transmission. New results demonstrate explicit instances where combining identical quantum channels violates this expectation, failing to produce a simple averaged output state. This stronger deviation from expected behaviour reveals inherent limitations within established methods for quantifying communication capacity.
Universität zu Cologne refines understanding of quantum limits
Until now, quantum communication protocols relied on an assumption about how channels combine, that averaging them always behaved predictably during transmission. New results demonstrate explicit instances where combining identical quantum channels violates this expectation, failing to produce a simple averaged output state. This stronger deviation from expected behaviour reveals inherent limitations within established methods for quantifying communication capacity.