Fair point. Depending on how you define it, all charges are an integral multiple of e or e/3 (see below). Either way, the relevant point to this discussion is that charge is quantized/discrete.
As for the Fractional quantum Hall effect, based on a quick glance, it seems that thus far only quasiparticees with charge e/3 have been discovered. So, while the theory could be correct, we will have wait and see if the other predicted fractional charges are detected.
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From the Quark wikipedia page you cited:
What is the quantum of charge?
All known elementary particles, including quarks, have charges that are integer multiples of 1⁄3 e. Therefore, one can say that the "quantum of charge" is 1⁄3 e. In this case, one says that the "elementary charge" is three times as large as the "quantum of charge".
On the other hand, all isolatable particles have charges that are integer multiples of e. (Quarks cannot be isolated, except in combinations like protons that have total charges that are integer multiples of e.) Therefore, one can say that the "quantum of charge" is e, with the proviso that quarks are not to be included. In this case, "elementary charge" would be synonymous with the "quantum of charge".
As for the Fractional quantum Hall effect, based on a quick glance, it seems that thus far only quasiparticees with charge e/3 have been discovered. So, while the theory could be correct, we will have wait and see if the other predicted fractional charges are detected.
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From the Quark wikipedia page you cited: What is the quantum of charge? All known elementary particles, including quarks, have charges that are integer multiples of 1⁄3 e. Therefore, one can say that the "quantum of charge" is 1⁄3 e. In this case, one says that the "elementary charge" is three times as large as the "quantum of charge". On the other hand, all isolatable particles have charges that are integer multiples of e. (Quarks cannot be isolated, except in combinations like protons that have total charges that are integer multiples of e.) Therefore, one can say that the "quantum of charge" is e, with the proviso that quarks are not to be included. In this case, "elementary charge" would be synonymous with the "quantum of charge".