SCIENCE - Quantum measurement carries information even when the measurement outcome is unread

Some tasks that are impossible in classical systems can be realized in quantum systems. This fact is exemplified by a new protocol that highlights an important difference between classical and quantum measurements. In classical mechanics, performing a measurement without reading the measurement outcome does not carry any information and is therefore equivalent to not performing the measurement at all. But in the new protocol, a quantum measurement that is performed but not read can carry information because the information can be encoded in the choice of the type of measurement that was performed. Read more at: http://phys.org/news/2013-08-quantum-outcome-unread.html#jCp

http://phys.org/news/2013-08-quantum-outcome-unread.htm