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Does an electron have a makeup

  1. Jan 14, 2005 #1
    While this question might seem ignorant to some I have not yet come across any literature that addresses and solves it.
    The question is, has anyone cracked open an electron to see what it is made of ? I ask because if it is more than one particle; couldn't it's internal reactions serve to cause a wobbling in a double slit experiment making it appear to have wave like properties.While the electron is propelled in a straight line it would almost certainly wobble before it hit the receiver even in a "vacuum".
    also I have yet to find a double slit experiment which it has been made apparent that it was done in a vacuum.If anyone can post a link that would be great
    Last edited: Jan 14, 2005
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  3. Jan 14, 2005 #2


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    I will answer to the only question reasonable,which doesn't include speculations.
    No.My guess is,they never will.In the Standard Model of Particles and Interactions,the electron is a fundamental particle,just like the others.Among the massive particles (let's exclude neutrino(s),it's still fuzzy),it has the smallest mass,therefore,roughly speaking,it has no other massive particles to decay into.Therefore it is a stable particle,just like the photon and all other fundamental particles.
    So far,no experiment has indicated an internal structure for the electron.

  4. Jan 14, 2005 #3
    As far as anyone knows, and according to the theory called QED, no, and they never will. An electron is a very simple beast; it doesn't have many characteristics. It's so simple that you can't tell one from another, literally. It's single reason for existence appears to be that it is the lightest particle that can carry an electric charge.

    No one has ever seen anything remotely like this, and if it was there they couldn't have missed it.

    I don't know if the dual slit experiment has been explicitly done with electrons, but you see diffraction and interference of them every time you turn on your computer monitor. We know all about it, and them. We have to, or the monitor doesn't work and you aren't reading this, and I'm not writing it.
  5. Jan 14, 2005 #4


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    A Google search for "double slit experiment with electrons" produces this as one of the first hits:

  6. Jan 14, 2005 #5
    This is an easy question to answer.

    The electron has no internal structure because it has an infinite lifetime. By this I mean it does not decay to any lower order components. We can show this is true because we know what all the other reactions of the electron should be and they fit together like a puzzle, if there were another decay mode, it wouldn't fit.

    The electron is a 'lepton', meaning that it is considered to be a point particle with zero volume. This idea is strongly support by experiment. Be aware not to confuse wavefunction (probability) with the 'size'.
  7. Jan 14, 2005 #6


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    Protons and neutrons do have structure. There is no sign that they "wobble". If electrons wobbled, then electron accelerators would not work, nor, for that matter, would proton accelerators.

    Also, I'm not sure that wobbling electrons would work in an electron microscope.
    Reilly Atkinson
  8. Jan 14, 2005 #7
    The Standard Model is the best theory that we have up till now when it comes to describing the properties of elementary particles (of which the electron is one); The electron does not have an internal structure for several reasons in this model. No experimental verification, no other elementary particles to decay into, no decay is possible because that would mess up the conservation laws that govern the weak interaction (eg : beta-decay) which are correctly bescribed by this modell. Also, no theory proves this possibility, in stead it is ruled out by the theory used to construct the standard model (eg field theories and group theory to govern the symmetries)...

  9. Jan 16, 2005 #8


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    Yes indeed, electrons have been cracked open. To wit, consider the electron-positron beam collision experiments.
    Reilly Atkinson
  10. Jan 18, 2005 #9
    In the Standard Model, the proton doesn't decay either and has an infinite lifetime. Yet it has an internal structure.
  11. Jan 18, 2005 #10
    Well, some think the proton may have an extremely long half-life, but I can't comment on the validity of that theory seeing how I don't know much about it.

    As for an electron substructure. Closest thing you could say by today's knowledge would be strings.

    I personally think we will discover an electron substructure in the future, but thats based on how I feel. But in the current model the electron doesn't need a substructure.
  12. Jan 23, 2005 #11
    An easy question to answer: I dought! However, I subscribe to your transaction.
    Yet could you just give a link, or any documented reference to what you said and why the electron "should" be a "point" particle; because I only got this as "talkings"
    BTW if you know the origin of the word "lepton" give me a hint. Any one but "dextercioby" :yuck: is welcome to answer.
  13. May 11, 2006 #12
    The electron must have a substructure.

    To do not need a substructure dose not mean there is no substructure. If there is no substructure in electron, it is hard to explain how can an electron absorb a photon.
  14. May 11, 2006 #13


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    But an electron does NOT absorb a photon! You're confusing an atom absorbing a photon via an electronic transition versus an electron sitting around and absorbing a photon. The latter doesn't occur.

    Darn it. We need to have an FAQ on this one.

  15. May 11, 2006 #14
    This is a common misconception. An electron does NOT absorb a photon.
    Photons can be absorbed by :

    1) atoms : The energylevels of an electron in an atom are NOT the same as the energylevels of a single electron.

    2) bulk materials like crystals, etc : the absorption occurs thanks to interaction with the phonons but NOT single atoms. The vibrational modes of the lattice vibrations absorb photons. So, this process is NOT the same as the one described in 1)

  16. May 11, 2006 #15

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    marlon and Zz,

    Sorry guys, but what are you talking about? An electron can absorb a photon, it's the basic QED vertex. A simple physical example is Compton scattering.
  17. May 11, 2006 #16
    The point is that a photon cannot be absorbed by a free electron. It can be scattered by a bunch of free electrons though. In the case of Compton scattering you do not get an absorption of photon by a free electron, so i don't get why you give this example.


    edit : we have had this discussion here
    Last edited: May 11, 2006
  18. May 11, 2006 #17


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    The standard model says that the electron has no substructure, this is true, but this hardly proves that the electron has no substructure.

    There are a lot of complaints about the standard model, a primary one of them is that it has too many free parameters. In looking for a deeper theory, we must look around for any coincidences that appear among the parameters of the standard model.

    For some examples of the coincidences, see:

    Last edited: May 11, 2006
  19. May 11, 2006 #18

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    It is true that a real electron cannot emit or absorb a real photon without something else happening. However, the requirement that the electron be on shell is not at all essential, so electrons can absorb photons. Don't let the names fool you, the difference between real (on shell) electrons and virtual electrons is somewhat arbitrary and definitely subtle. I brought up Compton scattering because QED describes it in terms of electrons emitting and absorbing photons. The two leading order diagrams each involve an electron emitting one photon and absorbing one photon. In particular, the outgoing photon is not the same as the ingoing photon, but you can never tell because photons are identical.

    I think I understand the point you and Zz were trying to make, and I agree that it is an often missed distinction. However, saying that electrons don't absorb photons is like telling the whole high energy physics community that their working language is nonsense.
  20. May 11, 2006 #19
    That is indeed the point.

    I don't follow. How about the conservation laws being violated (lepton number, J-momentum ???)

    I don't agree that the difference between real <---> virtual is arbitrary. I mean the definition based upon the fact that real particles are on mass shell is very straightforward. "The more" a particle is off mass shell, "the more" it is virtual. That is how i look at it and how i have always learned it.

    Correct but the electrons involved are not single free particles. That's why i had difficulties with your giving this example within the context of my first post.

    Well, to be honest when one speaks about "an electron", one refers to "one free electron". I know this can be debated but the general impression will be exactly this one. That is also why we get many such "electrons absorb photons"-misconceptions in this forum.

  21. May 11, 2006 #20


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