Talk:Atomic electron transition

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Previous discussion while the article was still titled Quantum leap is now at Talk:Quantum leap.

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"few nanoseconds or less"[edit]

First, the timing depends on the energy gap value. Second, it is generally not correct to suggest a picture like

  • the "↑" state before T0
  • transition started at T0
  • intermediate state between T0 and T1
  • transition ended at T1
  • the "↓" state after T1.

In the Schrödinger picture, we will always see some superposed state with the ↑ amplitude gradually decreasing and ↓ amplitude increasing. More general, the moment of a transition is always uncertain, and speculation such as "transition started at… and ended at…" do not have a sense. Incnis Mrsi (talk) 20:03, 22 September 2012 (UTC)

The moment (on the time scale) of a transition is uncertain (Poissonian statistics for a single atom/ion). Nevertheless the time for a transition (jump) is always shorter then statistical period of jumping cycle (interval between jumps) - obtained from density matrix ("superposition"). You can see (experimental - not speculation) it in wiki reference[1] (page 3). The probability for given state is very close to 1 between jumps. It is similar as the radioactive decay. A given (long-living radioactive) nucleus is in an excited state (with probability about 1) until its decay (unpredictable when but statistically predictable from this matrix element). But it does not mean that nucleus is decaying - e.g. millions years - and that we can not say (at any time) which (chemical) element it is (In reality, decay/transition itself is very fast - "few nanoseconds or less"). (talk) 13:09, 2 October 2012 (UTC)

Quantum leap[edit]

As far as I know this phrase is slightly more specific than "big increase". The phrase is more synonymous with "paradigm shift", and presumably has arisen because quantum mechanics is one of the most important discoveries in science, and the word "leap" is in some senses similar to "advance" (eg, "a giant leap for mankind"). Hence, probably, some layman heard this phrase and assumed it meant "the advance in physics associated with quantum theory" and it stuck. Not that I'm an etymologist or a lexicographer or anything. — Preceding unsigned comment added by (talk) 19:23, 24 January 2013 (UTC)

I think the link is simpler and more analogous than that - it's a not a big nor a small but a definite jump, without significant intermediate steps. (talk) 13:07, 30 April 2013 (UTC)

Removed obscure sentence[edit]

I removed the following sentence. It is expressed obscurely (what is "doubt"?) and it does not give any context or motivation. It appears to concern stimulated emission (or absorption) in an individual atom, so it would be quite interesting to see it explained.

The prediction expressed in the paper[1] and doubt was present in the 1980s.[2] Nevertheless it was shown experimentally, that the fluorescence rate of a single atom can not be calculated by Maxwell-Bloch equations. — Preceding unsigned comment added by (talk) 17:43, 27 April 2015 (UTC)