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Electromagnetic fields (nuclear & electron)

  1. Aug 9, 2005 #1


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    electromagnetic fields (nucleus & electron)

    An interesting conundrum is the nature and makeup behind the electromagnetic field. Quantum Mechanics was developed, for many reasons, but one perhaps, to greater introduce the notion of particle-particle interaction. More precisely to explain each of the fundamental forces as particle-particle interactions with the basis of fundamental particle physics. This greatly extended the use of mathematics as physics sought without intention to do from the start.

    One idea that always seems to come up a lot is what particles make up the EM field, why is it almost always just talked about as a field and not smaller inter-subatomic point particles? In einsteins special theory of relativity, section:
    XIX. The Gravitational Field
    Albert Einstein (1879–1955). Relativity: The Special and General Theory. 1920.

    there is stated: "" “IF we pick up a stone and then let it go, why does it fall to the ground?” The usual answer to this question is: “Because it is attracted by the earth.” Modern physics formulates the answer rather differently for the following reason. As a result of the more careful study of electromagnetic phenomena, we have come to regard action at a distance as a process impossible without the intervention of some intermediary medium. ""

    source: http://www.bartleby.com/173/19.html

    It further goes on to the suggestion that there are particles which are created by the earths gravitational field which are responsible for the force, that forces can be explained in such a manner. There also is commonly the idea that a field exists, in nature - a medium which is responsible, and many-a-time does not require the explanation of 'why' & 'how'. It is just disturbed by particle or energy in it. This is perhaps best and most suitable for the fundamental theory of how gravity works since it exists across all matter/energy regardless.

    Slightly getting off topic =>

    let us consider two lead balls of identical size and make in an empty portion of space which is not under any other influence by any other externally operating forces, including EM - Gravity - the Strong and Weak nuclear forces. This takes us to consider a sort of galilei-newton plane, which adhere's to the " law of inertia, can be stated thus: A body removed sufficiently far from other bodies continues in a state of rest or of uniform motion in a straight line. "

    source: http://www.bartleby.com/173/19.html

    now by convention and by the fundamentals of particle physics we have been asked to believe that the two balls would attract one another through the field defined as gravity i.e "the universal law of graviation" - every object attracts every other. But this goes against classical physics in its design of basic and fundamental motion. An object must be supplied force - energy to work and should not move unless been applied a force by another external body. Classically Electromagnetics is built in such a way that there are opposites (charges with opposite signs) which attract, like charges repel.
    In relation to a proton -&- electron,
    this means that they will have different properties, that there EM fields will be opposite. But with the example of the two lead balls, and if we apply this same line of thought, we cannot discriminate against two bodies which are identical is mass, and makeup. There must be something opposite which exists - but cannot. This is further troubling since a lot of theories and concepts have been created off the backbone of Electromagnetics since it has been so successful, what with the equations of maxwell and so forth...


    now getting back to the electromagnetic field,

    what is really interesting and should be looked at is when a free neutron undergoes beta minus decay in 10.4 min, and creates a proton, releasing and electron and an anti-neutrino -----> where is the description of the electromagnetic field? we don't see this in feynmann diagrams?

    1 1 0 _
    free n + 10.4 min ----> p + e + n
    0 +1 -1

    Now in feynmann diagrams, there are depicted 3 quarks inside the neutron, (ddu) (2 down, and 1 up). 1 quark transforms through a decay path which is the heavier one, the down, and creates an up quark - an electron and anti-neutrino. This now creates a proton which has 2 up quarks and 1 down (uud). But where is the depiction of the creation electromagnetic field. The proton undergoes a different spin as-well, a J = 1 (quantum total momentum angular operator) due to the individual spin of the quarks which are

    1 1 1
    _ - _ + _ = J = 1

    2 2 2

    (1/2 for an up quark, -1/2 for down)

    So this unique overall spin and the fact that one other quark is an up instead of a down paints the picture of a particle - a proton with fundamentally different and new properties to that of the earlier neutron. But where is the explanation of the EM field which is created around the particle, are we simply just to accept that this new spin and different quark allows the proton to interfere with the supposed EM medium around it? When anything in particle physics is applying a force on something else, this action takes energy and work. So the systems of nuclei must have these fields setup around each charged particle with a field of particles which is the EM field. These particles thus apply forces and interact with other changed particle.

    Or is the EM field a supposed medium which exists like more believably the gravitational field may be, but why then can't we apply the thought that these fields exist made up of particles which are distrurbed by matter / mass and energy
    Last edited: Aug 9, 2005
  2. jcsd
  3. Aug 10, 2005 #2


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    I don't get it.

    Your "essay" here appears to completely ignore QED, as if it doesn't even exist. Why is that? This is especially strange considering that currently, the MOST accurate agreement between experimental and theoretical value is the electronic gyromagnetic ratio. This ought to mean something regarding the validity of QED.

  4. Aug 10, 2005 #3
    I am afraid you are mixing QM with QFT. They are NOT the same, you know.

    ok, this is a popular remark. The answer is very simple and covers the very foundation of QFT, which you obviously seem to be missing.

    A particle is an excitation of a field. When a field (a vibration thereof)goes from one energy level to another, respecting einstein's energy relationship, the amount of energydifference dE corresponds to a particle of mass dm. The einstein energy relationship connects the dE and the dm part.
    The QM properties of a particle are determined by conservation laws, which arise due to symmetry of the formula's that describe the physics.

    Did you realize this ?

  5. Aug 10, 2005 #4


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    How do these replies explain the particle properties of the EM field around an electron or proton. I'm aware of concervation laws and the symmetry of formula's but this does not explain anything. Reread the section of beta minus decay....
  6. Aug 10, 2005 #5


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    Excuse me, but how is your reply answered my question on why you ignored completely QED? QED IS the quantum field theory of electromagnetic interactions. Why is it GLARINGLY missing in your discussion? Yet, you keep asking where is the explanation and the description? QED covers whole books! Did you somehow missed this?

    And beta decay is a WEAK interaction, not an electromagnetic interaction! It is only within the ELECTROWEAK theory is there unification between electromagnetic interaction and the weak interaction. So what in the world are you asking about with the beta decay not having any electromagnetic component? That's like asking why is blue not red!

    Either you address these questions, or I will assume that you are formulating your own "personal theory". If that is the case, then I strongly suggest you reread the PF guideline that you have explicitly agreed to upon join this forum. You are then welcome to submit your theory to the IR section of PF.

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