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Quantum View of Electron and Photon

  1. Feb 7, 2014 #1
    Quantum View of the Electron and Photon

    Sorry if the questions sound too amateurish.

    1. Is electron a packet of matter, while a photon a packet of energy? or is photon just a force carrier?

    2. Can the mass of an electron be converted into energy, and then into electromagnetic radiation
    i.e. photons?

    3. Rest mass of a photon is said to be zero. However, if photon is a packet of energy then wouldn't that energy theoretically correspond to some mass (via e=mc2)?

    4. The electrons have half integer values as spin. How does QM explain the absence of a charged particle with full integer spin? or why

    5. Can a Boson be converted (at east theoretically) into a Fermion?

    i.e can matter (?) be converted into a force carrier?

    6. A photon is part of the electromagnetic spectrum. Electron is part of electricity. Electricity can create an electromagnetic

    7. Is space-time a-priori or Electromagnetic Radiation?
    Last edited: Feb 7, 2014
  2. jcsd
  3. Feb 7, 2014 #2
    Matter(electron-positron) can be created out of two large momentum photons and the mass of electrons is already measured in energy units - eV so no need to convert mass into energy.

    Some similar questions motivate physicists to believe that all elemenary particles are aspects of something else - strings, branes, loops, something else entirely, etc. If it seems obvious and logical to me, it must be obvious to everyone else esp. to those with physics majors.
    Last edited: Feb 7, 2014
  4. Feb 7, 2014 #3


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    Both electrons and photons are pointlike elementary particles. A photon is not "just a packet of energy", it also carries momentum and spin, and most importantly it couples to the electromagnetic charge and current.

    Not by itself, but an electron can collide and annihilate with a positron, producing two photons. All of their energy goes into the energy of the photons directly, it's not correct to think of the conversion into energy as an intermediate step.

    In place of E = mc2 the more general relationship that holds for all particles is E2 = p2c2 + m2c4. So even a massless particle like the photon can have energy by virtue of its momentum.

    The W meson is an example of an elementary particle that has charge and integer spin.

    Not in the Standard Model. It can happen in speculative "Grand Unified Theories".
  5. Feb 8, 2014 #4
    thanks Bill_k and Maui
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