I heard from a teacher at University, he said something like "let's suppose that the electron and the proton have exactly the opposite charge even though that's not exactly true". I didn't have the chance to ask him which was the difference and I didn't want to wait until Monday to know. I also heard something similar a few weeks ago but now I'm searching on the internet and my textbooks and i can't find any difference in the measures of charges... Maybe i just misundertood something.
It seemed really weird to me cause i thought that "e" was the quantum of electric charge (without thinking of quarks), and if the proton had some similar but slightly different charge then that wouldn't be true.
If nobody has heard about this maybe I just misunderstood my teacher... I'll ask him to see if i can solve the misunderstanding.
Thank you for your time and sorry for my bad english.