In
quantum information theory, the identity channel is a noise-free
quantum channel
In quantum information theory, a quantum channel is a communication channel which can transmit quantum information, as well as classical information. An example of quantum information is the state of a qubit. An example of classical information i ...
. That is, the channel outputs exactly what was put in.
[.]
The identity channel is commonly denoted as
,
or
.
References
Information theory
Mathematical analysis
{{physics-stub