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Property that gives electrons charge.

  1. May 3, 2009 #1
    Im a new student and I have searched high and low for a clear explanation as to why electrons and protons have something called charge.

    So far my basic understanding stands at

    1. Charge is a fundamental conserved property of certain particles like electrons and protons.

    2. This property of charge will create a electrostatic force that will draw these two particles together.

    Now my questions come.

    What is it about an electron that will produce a property called charge that is opposite of the same force that is created by a proton.

    An analogy to my question would be take my height 5'11''. It is a property of my body. This property exists because I have bones and these bones have length, and my body has a certain layout that causes it to have a particular length or height.

    What inside an electron will produce a charge, is it inside the electron or is this charge simply a product of the way the electron spins.

    Everywhere i read the definition they keep saying that electrons have charge but why? And why is this charge opposite and equal to a proton.

    Thank you
  2. jcsd
  3. May 3, 2009 #2


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    Homework Helper

    Well, you might have to ask string theory for the answer to that question ;-)

    There is no generally accepted explanation for why an electron has charge. As far as anyone knows, the electron is a fundamental particle. It doesn't have any components or structure inside that you could point to as a reason it has a particular charge. (It's not spin.) The proton does have some substructure, namely it's made of 3 quarks (plus "junk" - no charge), but you could ask the same question about the quarks: why do they have charge? And nobody really knows the answer.

    As for why the electron has a charge exactly opposite to that of a proton: charge is quantized. In all free particles in nature, it occurs in multiples of a unit charge, and that unit charge happens to be the charge of the electron. That's not a full answer, I know, but once you get beyond that, it's similar to asking why charge exists at all - there's no really good answer.

    Physicists just say that the charge is one of the numbers that identifies an electron as distinct from, say, a positron.
  4. May 3, 2009 #3
    So im asking a question that no one can clearly explain.... :(

    I know that + and - were just symbols assigned to two forces that made two particles approach each other.

    And I know about quarks and leptons and you're absolutely right that we can go on and ask why do quarks have the property called charge that seems to draw particles toward each other.

    The only reason we know about this force is we observe its phenomenon. Otherwise for example the color of my toothbrush does not make it a more effective or less effective toothbrush.

    Yes energy is quantized, but charge is then a force created by a certain property that cannot be defined

    Thank you
  5. May 3, 2009 #4


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    Staff: Mentor

    In quantum field theory, the property that we call "charge" is the conserved quantity that arises (via Noether's Theorem) from the fact that the universe apparently has "local U(1) gauge symmetry."

    Of course, this begs, the question, "why does the universe have local U(1) gauge symmetry?" :uhh:
  6. May 4, 2009 #5
    I think of charge as the divergence of the electric field.
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