====== Electron / Quark charge balance ====== {{tag>Inexplicable}} It's known that all atoms are based on a structure where the 'negative' electric charge of the electron(s) (conventionally known as '-1') //exactly// balances the 'positive' charge of the corresponding proton(s) in the atom's nucleus. [ see notes below ] The proton's electric charge comes from the [[content:physics:quantum_physics:quarks|quarks]] from which it's built. Protons are composed of two up quarks, each with a 'fractional' charge of +⅔ , and one down quark with a charge of −1⁄3 , Thus giving a total charge of //exactly// +1. This means that all non-ionised atoms (i.e. ones having the 'correct' number of electrons) have absolutely no overall electrical charge. There is currently no explanation as to why the charge-balances //exactly// cancel. Which is especially enigmatic given that electrons and quarks are known to be very radically different particles. If the charge-balances //didn't// cancel exactly, the universe as we currently understand it would not be viable. //Notes:// [1] It's not known //how// //closely// the charges match. But no discrepancy of any kind has ever been measured. And for the Standard Model to remain intact, it's calculated that accuracy of the match must reach at least 22 decimal places (roughly one part in 10 billion trillion). [2] Most nuclear physicists currently assume that electrons and quarks are //not// built from sub-components. As yet, there has never been any experimental evidence to suggest that they might be. [3] Since the discovery of the quark's 'fractional' charges, the question arises as to whether a better convention might be to say that the electron has a charge of 3 , the up quarks each +2 , the down quarks -1. ''Editor's note :''\\ '' The Standard Model has no explanation for the exact charge balance, and Wikenigma has so far been unable to source any peer-reviewed scientific literature which tackles the question. Although Wikenigma policy is to always require and include links to academic references, it's overlooked in this instance, given the crucial importance of the subject.'' ~~stars>4/5~~