Since to become excited an electron in its ground state have to absorb a particular frequency of light otherwise they will just pass through each other, I'm thinking how can the electron measure the photon and decide whether to absorb it or not? I even read that 1 single photon with sufficient high energy can excite 2 or more electrons at once and one of the electron may be quite far away unbelievable as I only know it is very rare for an electron to absorb 2 photons at once so that makes me believe that electron can sense nearby photons.

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    $\begingroup$ A photon is absorbed by an atom, not by an electron. $\endgroup$ – safesphere Feb 1 '19 at 13:46
  • $\begingroup$ What you describe is just a qualitative picture of what happens. You can derive the selection rules by studing the hamiltonian in presence of light, and the electron will follow what this rules say. However you should consider that the selection rules only say which probability has a certain event to happen, since this is a stochastic process. I think you should read something with a bit of math to have the ideas clearer. $\endgroup$ – Landau Feb 1 '19 at 13:52
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    $\begingroup$ And why not to let the photon arrive there and if energy fits than absorption occurs? $\endgroup$ – Alchimista Feb 1 '19 at 13:56
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    $\begingroup$ Electrons and photons don't have knowledge or senses. They just are, albeit in mysterious ways. How does the coin know it fits in the hole in your pocket? $\endgroup$ – my2cts Feb 1 '19 at 20:26