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Quantum mechanics

Evolution stopped in its tracks

Nature volume 451, pages 137–138 (2008)Cite this article

How do you watch the evolution of something that doesn't evolve? In the classical world, even posing this question would provoke raised eyebrows. But where quantum physics is involved, no question is too silly.

“A watched pot never boils,” the saying goes, although the laws of physics tell us that this can't be true. More precisely, the cosy intuitions of classical physics tell us this can't be true. But enter the topsy-turvy realm of quantum physics, and the saying and the science converge. Specifically, a phenomenon known as the quantum Zeno effect states that if we find a system in a particular quantum state, and repeatedly and frequently check whether it is still in that state, it will remain in that state. It does this even if, without constant checking, it would evolve to another state. The watched quantum pot never boils.

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Figure 1: A step forward, a step back.

References

  1. Dowling, J. Nature 439, 920–921 (2006).

    Article  ADS  Google Scholar 

  2. De Liberato, S. Phys. Rev. A 76, 042107 (2007).

    Article  ADS  Google Scholar 

  3. Arntzenius, F. Monist 83, 187–208 (2000).

    Article  Google Scholar 

  4. Aharonov, Y. & Vaidman, L. Phys. Rev. A 41, 11–20 (1990).

    Article  ADS  MathSciNet  CAS  Google Scholar 

  5. Aharonov, Y. & Vaidman, L. Phys. Lett. A 178, 38–42 (1993).

    Article  ADS  Google Scholar 

  6. Aharonov, Y. & Rohrlich, D. Quantum Paradoxes: Quantum Theory for the Perplexed (Wiley-VCH, Weinheim, 2005).

    Book  Google Scholar 

Download references

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  1. Lev Vaidman is in the Physics Department, Tel Aviv University, Tel Aviv 69978, Israel. vaidman@post.tau.ac.il,

    Lev Vaidman

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  1. Lev Vaidman
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Vaidman, L. Evolution stopped in its tracks. Nature 451, 137–138 (2008). https://doi.org/10.1038/451137a

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