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Can someone explain to me the difference (if any) between measurement of the first kind and quantum non-demolition measurement?
Thanks!
Thanks!
Demystifier said:Can someone explain to me the difference (if any) between measurement of the first kind and quantum non-demolition measurement?
Thanks!
Why? Do you think this question is too easy? If so, can YOU answer it?audioloop said:you ?
asking that ?
...very suspect
Demystifier said:Why? Do you think this is too easy? If so, can YOU answer it?
First-kind measurements, non-demolition measurements, andDemystifier said:but I ask specifically for the DIFFERENCE between the two. I found the explanations of either of the two concepts in many places, but I could not find any single book or article that explains BOTH concepts at one place. And I must admit, from various explanations of these concepts at various places, I still cannot see clearly what exactly is the DIFFERENCE between them.
Thanks, the difference is now clear to me.audioloop said:First-kind measurements, non-demolition measurements, and
conservation laws
http://arxiv.org/pdf/quant-ph/9804026v3.pdf
...Any QND measurement is of the FK, but the inverse becomes true only when Qˆ is a constant-of-motion of S,...
Quantum measurement is the process of obtaining information about a quantum system, such as its position or momentum. This process involves interacting with the system and causing it to collapse from a superposition of states to a single definite state.
The first kind of quantum measurement, also known as the projective measurement, is a measurement that completely collapses the quantum system into one of its possible states. This type of measurement is irreversible and provides a definite outcome.
Non-demolition measurement is a type of quantum measurement that does not entirely collapse the system, but instead provides information about the system while still preserving its superposition of states. This type of measurement is used in quantum systems that require continuous monitoring without disturbing the system.
The main difference between the first kind and non-demolition measurement is the effect they have on the quantum system. First kind measurements completely collapse the system, while non-demolition measurements only provide partial information while preserving the superposition of states. Non-demolition measurements are also reversible, while first kind measurements are irreversible.
Quantum measurement is essential for understanding and manipulating quantum systems, which have various applications in technology, such as quantum computing, cryptography, and precision measurements in fields like biology and medicine. It also plays a crucial role in fundamental research in quantum mechanics and understanding the nature of reality at a microscopic level.