On Mar 22, 10:29*pm, wrote:
When an electron jumps from one permitted energy level to another it
absorbs a photon with an energy equal to the difference between the
two levels. Lets call it x Joules.
Can it achieve the same jump by absorbing two or more photons with a
total eneregy of x joules? If so is there a finite time limit within
which the two photons must be absobed and what is the time limit?

Very creative question. Searching the web for "multi-photon
absorption" indicates the answer is "yes". I didn't read deep enough
into the articles to determine any time limit (but my bet would be
that Heisenberg would come into play).

So here's what I've always wondered: Although there is a very small
range of energies that allow an electron to jump energy levels, it is
indeed a range. Why is it not an infinitely precise energy value?
(Which one may argue would then never allow "jumping" to occur.) Is
the size of the range based on uncertainty somewhere? If an electron
jumps so that the energy is at the very bottom or very top of the
range for say, the L line, then does the emission occur more quickly?
I guess I could just work through the equations some day....