
Scientists present the most accurate time measurements of quantum jumps to date - dnetesn
http://phys.org/news/2016-11-scientists-accurate-quantum-date.html
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CoryG89
Is a quantum jump the same as or related to what I have referred to as a
"quantum leap" in the past? IIRC, a quantum leap is supposed to be when a
electron changes it's orbit. Which I believe was also thought to be
instantaneous?

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btilly
Yes.

As for timing, it takes a few hundred attoseconds. See
[http://www.nature.com/nature/journal/v436/n7049/full/nature0...](http://www.nature.com/nature/journal/v436/n7049/full/nature03833.html).
Under 1 quadrillionth of a second is, for most purposes, instantaneous. Which
is why you were told it was instantaneous. But it is now a measurable process.

The timescale that we are talking is what it takes light to travel a
micrometer or so. Which is about the size of the smallest bacteria.

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imglorp
> light to travel a micrometer or so.

The Bohr radius is around 5e-11 m, while the bacteria is around 1e-6 m. That
seems like a gulf of difference. What's taking it so long?

~~~
btilly
I'm qualified to quote original sources found from Wikipedia, not to explain
them. :-)

That said, in the Bohr model, electrons move at around 1% of the velocity of
light. Multiply by pi for half the circumference, and you're in the right
general ballpark that the wave takes this long to propagate both ways around
the atom and then set up interference with itself resulting in the new
orbital.

(A highly inaccurate picture of what is really happening, but it gives basic
intuition.)

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Ono-Sendai
I have a simulation of a quantum jump as well, maybe I should polish it up and
get it published in Nature also.

