Quantum Measurements, Instruments, and Uncertainty Principle ( The Proceedings of the Second Sendai Workshop on Quantum Probability and Quantum Information)
Masanao Ozawa
Abstract
The Heisenberg uncertainty relation for measurement noise and disturbance states that any position measurement with noise ε brings the momentum disturbance not less than h/2ε. However, this relation holds only for restricted class of measurements. Here, we discuss universally valid uncertainty relations for measurement noise and disturbance, which hold for all the possible quantum measurements.