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I read in Auletta's quantum mechanics (section 11.2) that the charge of the proton is, apart from the sign, approximately equal to that of the electron.. What bothers me is the word approximately, shouldn't $q_e=q_p$ because any small difference on the atomic scale will induce a huge electric charge for macroscopic bodies.


marked as duplicate by BMS, ACuriousMind, Prahar, Kyle Kanos, Brandon Enright Sep 27 '14 at 1:29

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    $\begingroup$ Already answered here: physics.stackexchange.com/questions/21753/… $\endgroup$ – Jasper Sep 26 '14 at 21:11
  • $\begingroup$ While there is a previous answer, you need to be careful which of the answers to trust and you need to read the fine print, especially the phrase "within experimental limits", which explains the phrase "approximately" in your source. Every other argument that people make in that answer that contains some "theoretical proof" using charge quantization, the standard model etc. is simply false. $\endgroup$ – CuriousOne Sep 27 '14 at 2:03