Editing Quantum Zeno effect (section)

==Description==
Unstable quantum systems are predicted to exhibit a short-time deviation from the exponential decay law.<ref name=Khalfin>
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}}</ref> This universal phenomenon has led to the prediction that frequent measurements during this nonexponential period could inhibit decay of the system, one form of the quantum Zeno effect. Subsequently, it was predicted that measurements applied more slowly could also ''enhance'' decay rates, a phenomenon known as the '''quantum anti-Zeno effect'''.<ref>{{Cite journal |last=Chaudhry |first=Adam Zaman |date=2016-07-13 |title=A general framework for the Quantum Zeno and anti-Zeno effects |journal=[[Scientific Reports]] |language=en |volume=6 |issue=1 |pages= 29497|arxiv=1604.06561 |doi=10.1038/srep29497 |issn=2045-2322 |pmc=4942788 |pmid=27405268 |bibcode=2016NatSR...629497C}}</ref>

In [[quantum mechanics]], the interaction mentioned is called "measurement" because its result can be interpreted in terms of [[classical mechanics]]. Frequent measurement prohibits the transition. It can be a transition of a particle from one half-space to another (which could be used for an [[atomic mirror]] in an [[atomic nanoscope]]<ref name="nanoscope">
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 }}</ref>) as in the time-of-arrival problem,<ref name=allcock>
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 }}</ref> a transition of a [[photon]] in a [[waveguide]] from one mode to another, and it can be a transition of an atom from one [[quantum state]] to another. It can be a transition from the subspace without decoherent loss of a [[qubit]] to a state with a qubit lost in a [[quantum computer]].<ref name=Stolze>{{cite book
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 }}{{Dead link|date=May 2024 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><ref>
{{cite web
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}}</ref> In this sense, for the qubit correction, it is sufficient to determine whether the decoherence has already occurred or not. All these can be considered as applications of the Zeno effect.<ref name=Franson>{{cite journal
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|s2cid=119071343
 }}</ref> By its nature, the effect appears only in systems with distinguishable quantum states, and hence is inapplicable to classical phenomena and macroscopic bodies.

The idea is implicit in [[John von Neumann]]'s early work ''[[Mathematical Foundations of Quantum Mechanics]]'', and in particular the rule sometimes called the ''[[Wave function collapse#History and context|reduction postulate]]''.<ref name="vonNeumann">{{cite book |title=Mathematische Grundlagen der Quantenmechanik |publisher=[[Springer (publisher)|Springer]] |year=1932 |isbn=978-3-540-59207-5 |page=Chapter V.2 |no-pp=true |last1=von Neumann |first1=J.}} See also {{cite book |title=Mathematical Foundations of Quantum Mechanics |url=https://archive.org/details/mathematicalfoun0613vonn |url-access=registration |publisher=[[Princeton University Press]] |year=1955 |isbn=978-0-691-02893-4 |page=[https://archive.org/details/mathematicalfoun0613vonn/page/366 366] |last1=von Neumann |first1=J.}}); {{cite book |url=https://books.google.com/books?id=Bo7jujlMqL8C&pg=PA80 |title=Quantum Measurements and Decoherence |publisher=[[Springer (publisher)|Springer]] |year=2000 |isbn=978-0-7923-6227-2 |page=§4.1.1, pp. 315 ff |no-pp=yes |last1=Menskey |first1=M. B.}}; {{cite book |url=https://books.google.com/books?id=mmhJ37o8fdwC&pg=PA315 |title=Quantum Measurements and New Concepts for Experiments with Trapped Ions |last2=Balzer |first2=C. |publisher=[[Academic Press]] |year=2003 |isbn=978-0-12-003849-7 |series=Advances in Atomic, Molecular, and Optical Physics |volume=49 |pages=315 |last1=Wunderlich |first1=C. |editor1-last=Bederson |editor1-first=B. |editor2-last=Walther |editor2-first=H.}}</ref> It was later shown that the quantum Zeno effect of a single system is equivalent to the indetermination of the quantum state of a single system.<ref>{{Cite journal |date=April 1997 |title=Quantum Zeno Effect and the Impossibility of Determining the Quantum State of a Single System |journal=Phys. Rev. A |volume=55 |issue=5 |pages=R2499–R2502 |bibcode=1997PhRvA..55.2499A |doi=10.1103/PhysRevA.55.R2499 |author=[[Orly Alter]] and [[Yoshihisa Yamamoto (scientist)|Yoshihisa Yamamoto]]}}</ref><ref>{{Cite book |chapter-url=http://www.alterlab.org/publications/Alter_Yamamoto_Quantum_Interferometry_1996.pdf |title=Quantum Interferometry |date=October 1996 |publisher=Wiley-VCH |pages=539–544 |chapter=The quantum Zeno effect of a single system is equivalent to the indetermination of the quantum state of a single system |author=[[Orly Alter]] and [[Yoshihisa Yamamoto (scientist)|Yoshihisa Yamamoto]] |editor=F. De Martini, G. Denardo and Y. Shih}}</ref><ref>{{Cite book |url=https://alterlab.org/publications/Alter_Yamamoto_Wiley-Interscience_2001.pdf |title=Quantum Measurement of a Single System |date=2001 |publisher=Wiley-Interscience |doi=10.1002/9783527617128 |author=[[Orly Alter]] and [[Yoshihisa Yamamoto (scientist)|Yoshihisa Yamamoto]] |isbn=9780471283089 |access-date=2021-12-04 |archive-date=2021-12-04 |archive-url=https://web.archive.org/web/20211204211255/https://alterlab.org/publications/Alter_Yamamoto_Wiley-Interscience_2001.pdf |url-status=dead }}</ref>