Quantum tunneling instantaneous

God Plays Dice
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The electron does not have a well-defined position or speed. There are no instantaneous jumps, and the propagation of any signals is limited by the speed of light.
 
God Plays Dice said:
http://m.phys.org/news/2015-05-physicists-quantum-tunneling-mystery.html

Does this mean that the tunnelling time was actually zero, and the electron 'skips' over the gap, or does it mean that the electron wave traveled at the speed of light followed by an instantaneous jump later on
The way I look at it (which is probably wrong) is that the electron exists as a fuzzy ball of probability. It only localizes when "observed" (for some value of observation that I can't define). Thus the electron is on both sides of the barrier. The article you linked seemed to be a computer simulation that claimed the observation localized it in zero time. That is not the same as the electron moving.

There are some important caveats: Most importantly, simulations are not experiments. They may lead to experiments, but until they do, they are just a new and potentially wrong (if the simulators missed something) way of looking at the model they are simulating. They can add insight, but they have lots of weaknesses.

Second, this seems to be a popular press release. The popular press is notorious for making complex scientific issues into simple pissing contests (look, FTL electrons!) between scientific theories. Science facts are often left to fend for themselves.

I will say the link you provided gives rise to some deep thoughts. It could easily lead to a testable hypothesis and new knowledge. It sounds like someone is doing good work.
 
God Plays Dice said:
does it mean that the electron wave traveled at the speed of light followed by an instantaneous jump later on
Despite the seemingly lack in the firm theoretical description of tunnel ionization, hasn't the article itself already anticipated the rise of such notion in the reader's mind by quoting Dr. Igor Ivanov, "A very interesting paradox arises, because electron velocity during tunneling may become greater than the speed of light. However, this does not contradict the special theory of relativity, as the tunneling velocity is also imaginary."?
 
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