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Basic Question: Positive and Negative Electrical Charge

  1. Nov 18, 2011 #1
    I am not a student of Physics. I want to know. I am curious. I never understood a basic thing. What is the difference between a positive and a negative electrical charge? What characteristics describe the two charges?

    Are they just something you mug up as a given example of the duality in the natural laws -- such as the existence two genders -- without probing further into the individual natures that distinguish the elements in the duality?
  2. jcsd
  3. Nov 18, 2011 #2

    Claude Bile

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    Aside from the obvious (like charges repel, opposites attract)?

    Particle physicists often use symmetry arguments to explain why positive charge must exist in conjunction with negative charge. For example, it can be argued that for each particle there must exist a corresponding anti-particle; and that anti-particle must possess a charge opposite to that of the original particle.

    One could then query why electrons possess negative charges etc. but this really boils down to why "normal" matter dominates ordinary matter, a question which is currently unresolved.

    This is not my field of expertise, so I'm hand waving a little here.

  4. Nov 18, 2011 #3
    One should be careful though to not confuse the proton as being the anti-electron, because it has the opposite charge of an electron. The antiparticle of the electron is the positron, not the proton.

    The idea of positive and negative charge came from experimental observations that some objects attracted each other, while others repeled each other. To explain this effect, it became convenient to come up with the idea of positive and negative charge. From a modern perspective, we now know charge comes from the U(1) gauge symmetry of the QED Lagrangian (I know if you are not a physicist, this just sounds like math jargon).
  5. Nov 18, 2011 #4
    "Probing further into the individual natures that distinguish the elements in the duality" is what goes on all the time in physics research, and has been going on for electric charge for a very long time.

    If you want to get deeper into the nature of electric charge, you probably need to learn the theory of QED and the charge renormalisation. It is fascinating, but demands a comprehensive knowledge of physics.
  6. Nov 19, 2011 #5
    I understand some of each of your answers. Thank you for taking the time.

    But I feel like I need some basic prep before I can understand the answer to my question.

    Could you point me to a very basic book on Physics that will be nice to read for a newbie? I must understand its contents and enjoy reading it.

    Thank you.
    Last edited by a moderator: Nov 23, 2011
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