Quantum circuits with mixed states
STOC '98 Proceedings of the thirtieth annual ACM symposium on Theory of computing
Classical and Quantum Computation
Classical and Quantum Computation
On the Hardness of Distinguishing Mixed-State Quantum Computations
CCC '05 Proceedings of the 20th Annual IEEE Conference on Computational Complexity
Proceedings of the forty-second ACM symposium on Theory of computing
On the complexity of approximating the diamond norm
Quantum Information & Computation
| Hi-index | 0.00 |
A channel is degradable if there exists a second channel that maps the output stateof the channel to the environment state. These channels satisfy the property that theoutput state contains more information about the input than the environment does. Acomplementary class of channels is the antidegradable channels, which admit channelsthat map the environment state to the output state of the channel. In this paper weshow that the computational problem of distinguishing two channels remains PSPACE-complete when restricted to these classes of channels. This is shown using a constructionof Cubitt, Ruskai, and Smith [1] that embeds any channel into a degradable channel,and a related construction for the case of antidegradable channels.