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Lamb shift and creation of mass

  1. Aug 5, 2004 #1
    A 2s electron in a hydrogen atom has more energy than a 2p electron.
    Quantum field theory says this is because the 2s electron interacts with itself
    by emitting and absorbing a photon.But what if the proton and the electron carry a charge which is always repulsive.Then a 2s electron which is closer to the proton on average will have a higher energy because of repulsion.And if space is filled with lots of small particles bearing this new repulsive charge,couldn't this charge be the cause of the reluctance of quarks and leptons to change their speeds.Couldn't this repulsive charge be the cause of the mass of all particles with rest mass?
     
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  3. Aug 6, 2004 #2

    anti_crank

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    Since I have absolutely nothing against your boundless kuriosity, here's the informal version. The Lamb shift corresponds to a number of Feynman diagrams of four vertices each (not just the one you mentioned). It turns out that this correction breaks a degeneracy otherwise present in the hydrogen atom. As for the idea of universal repulsion, I doubt it will work: if it is strong enough to be measurable in the Lamb shift, we should have surely observed it by now in other interactions. Interestingly, mass generation in the standard model is done by the Higgs vacuum, so indeed it is the result of an external field (and not intrinsic to the particles), but this is far too technical to formalize here.
     
  4. Aug 6, 2004 #3
    The Feynman diagram I mentioned is the most important contribution isn't it?
    There is universal attraction in the universe - gravity- why not some universal repulsion? I must find some more evidence for it...
     
  5. Aug 6, 2004 #4

    anti_crank

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    I will have to look up which diagram is the main contribution to the Lamb shift. But as for universal (ie mass-independent) repulsion, how do you propose to find it? As gravity is a universal attraction, the universal repulsion would simply result in a lesser net measurement of the strength of gravity: we would not be able to separate its effects outright. As an analogy, if we measure the net value 2, we cannot infer the physics is in fact 3-1 unless there's some other way to separate them. If the repulsion were indeed universal, that wouldn't be the case. There were some papers and experiments in the late 80's and early 90's that suggested another fundamental interaction acting on baryon number; they have largely been discredited since.
     
  6. Aug 6, 2004 #5
    anti crank:
    the universal repulsion would simply result in a lesser net measurement of the strength of gravity

    Kurious:
    Not if the universal repulsion only works over a short range such as 10^-10 metres.
    At shorter range its effects would be difficult to separate from a powerful force like the colour force.
     
  7. Aug 6, 2004 #6
    As the universe expands the density of mass-giving particles would go down and so would the mass of large bodies like the Earth.In a 100 year period there would be a change in volume of the universe of:
    [ (100/ current age of universe in years) x 10^26 (current radius)] ^3 = 10^54 kg/m^3
    This is so small compared to the current volume 10^54/10^78 = 10^-24
    that we would not be able to detect the density change for mass-giving particles.
    Therefore we can't rule out the idea that there are a finite and constant number of mass-giving particles filling space.
     
  8. Aug 7, 2004 #7

    anti_crank

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    This scale / energy range has been very thoroughly probed, and AFAIK there are no surprises there. To avoid the color force, you can go to an EM process like electron-positron colliders. I must congratulate you though on having found the best loophole in the business: "the effects are so small as to be unmeasurable". You can slip almost any kind of interaction through that one by making it small enough. At this point, however, allow me to remind you that physics requires proof of existence - otherwise we have to allow anything in that's not currently excluded. Try to think of a way to show it experimentally, or at least get some theoretical motivation for it.

    Gravity is 'universal attraction', yes, but so far it is different from all other interactions. Until we can quantize it, we won't know what a repulsive counterpart may look like on symmetry principles, and I've already explained that classically you cannot distinguish the separate two from the resulting whole. I can give you plenty of examples for how some feasible theoretical arguments may look:

    1) Magnetic monopoles - classically, they would restore symmetry to Maxwell's equations and in QED, explain why charge is quantized. None have been found, but nonetheless we have good reasons to look for them, and we still do. Do you need what you're proposing for some framework, or are you just brainstorming here?

    2) Neutral weak currents - these were required for the completeness of the GWS model and predicted a few years before their discovery. It helps if you know what you're looking for, and why. Got anything specific in mind?

    Edit: you were right, the electron mass renormalization is the most significant contribution to the Lamb shift. The contributions are shown here: http://www.pha.jhu.edu/~rt19/hydro/node8.html
     
    Last edited: Aug 7, 2004
  9. Aug 7, 2004 #8
    I'm looking for an explanation for the cause of mass that can fit in with a modification to relativity of the type (1 - v^2/c^2 + small constant)^1/2 - this keeps
    Tab = Tba and the magnitude of the four momentum of a photon at zero.
    It would mean a rest mass can reach the speed of light at a finite but very large energy input and that lengths do not contract to zero if the speed of light is reached
    by an observer -and hopefully it would also mean that a proton moving at the speed of
    light in the region of a singularity in a black hole would have a finite radius and there fore if all particles move at the speed of light at the singularity the singularity as a point of infinite density would not exist.
    Now, I would have to have a physical justification for the small constant.I looked at Einstein's own derivation of the Lorentz transforms and concluded that a small constant would be needed if a clock with zero velocity in some frame of reference
    ticked faster than a clock at rest should.I then concluded that this would mean that a field with the opposite effect of a gravitational field could be speeding up a clock at rest - that field would have to fill all of space because a clock could be located anywhere. But because I also want to explain the cause of mass (which relativity does not) and of relativistic mass increase and to introduce some quantum mechanics into relativity, I decided that some particles (which can be quanta of fields) filling space would be a useful way of explaining mass and fast ticking clocks.These particles having the opposite effect on clocks to normal mass would be associated with a repulsive force.The small constant, I guess would be about 10^-40 at the smallest so that at a singularity a proton could not get smaller than the planck length - a reasonable supposition, I think.But I set the small constant to 10^-38 so time dilation can never be greater than the current age of the universe which is about 10^19 seconds.I have used my ideas to calculate the maximum classical angular momentum of a black hole and I got a value of 10^42 which compares favourably with the general relativistic calculation of
    10^41.My calculation assumes that the distance between quarks ( using the small constant to reduce the diameter of a neutron at rest from 10^-15 to 10^-15 x 10^-19) is 10^-34 metres for all quarks moving at the speed of light in a spherical region of radius 10^-15 metres centred on where the singularity used to be (10^-15 is 10^19 x 10^-34 - there are 10^19 neutrons on a radius of a sphere containing all 10^57 of a black hole's neutrons).


    According to standard relativity theory the maximum angular momentum of a black hole is given by: GM^2 / c

    For a black hole of a few solar masses this amounts to 10^41
    In my theory 10^57 neutrons spin at a maximum average speed of 10^8 m/s at a maximum distance of 10^-15 metres.The neutrons in my theory will have a mass
    that is about 10^19 x rest mass ( 1 / small constant = 10^19) i.e 10^19 x 10^-27 = 10^-8 kg/neutron.
    Using the classical formula angular momentum = mass x velocity x radius
    we get my prediction of the maximum angular momentum of the black hole.
    This is: 10^57 (number of neutrons) x 10^-8 x 10^8 x 10^ -15 = 10^42

    This is close to general relativity's prediction of 10^41

    I have done a calculation for the entropy of a five solar mass black hole (which I am not sure about) and my calculation gives 10^53 JK^-1 compared to the GR result of 10^55 JK^-1.

    As for magnetic monopoles:if their existence means inflation theory is wrong then I am all for them existing because I think the simplest explanation for the coincidence in density of baryonic mattr and dark energy is that the universe has never been smaller than 10^25 metres and won't get larger than 10^27 metres.However I think the universe oscillates and is not stationary as some people advocate.
     
    Last edited: Aug 7, 2004
  10. Aug 7, 2004 #9
    If the speed of all particles is related to electric field/magnetic field ( E/B = c for a photon. E and B would form between a quark,for example, and magnetic monopoles and electric charges which surround a quark.The quark would have to possess a permanent magnetic charge) mass could just be a reluctance of a magnetic field associated with a quark to change.In other words the energy required to accelerate a mass could be the energy needed to decrease the magnetic field by forcing some monopoles to dissipate some magnetic charge which would then travel off through space. E/B would increase as a quark picks up speed.

    We can imagine quarks and leptons being surrounded by a cloud of mass-giving particles.Let's postulate that for a force carrier like a photon to exert a force on a quark,for example,the photon
    collides with the mass-giving cloud and compresses it.The mass-giving particles will thus increase in density and the speed of them and the quark will increase.Also we would expect by relatvity theory that the mass of the quark would increase i.e the smaller, denser cloud is associated with a greater mass (the length of the cloud will be inversely proportional to its mass under special relativity).A small clock placed in the cloud and moving with the cloud would be expected to run more slowly than a clock at rest
    in some frame.Could the greater density of the mass-giving particles in the cloud be slowing the clock down somehow.If we think of a clock as being a photon bouncing between two mirrors, then the answer is surely yes,
    because a greater number of mass-giving particles between the mirrors
    would mean that the photon would be absorbed and scattered more times and so would take longer to travel from one mirror to the other.
    But there would have to be lots of mass-giving particles of different sizes so that photons of different wavelengths bouncing between the mirrors would
    be scattered equally.A CLOCK AT REST IN SPACE EMPTY OF LEPTONS AND QUARKS WOULD OBEY NORMAL SPECIAL RELATIVITY BUT A CLOCK AT REST CLOSE TO LEPTONS AND QUARKS WOULD TICK FASTER BECAUSE MASS-GIVING PARTICLES WOULD BE LESS DENSE AROUND LEPTONS AND QUARKS
    ON ACCOUNT OF THE REPULSION OF LIKE CHARGES (WITH VERY SHORT RANGE FIELD - LESS THAN 10^-18 METRES) CARRIED BY EVERY PARTICLE IN THE UNIVERSE. A mass like the Earth could compress the mass-giving particles as its gravitons collide with them and so also slow down a clock.
    A proton could get most of its mass from gluons because the gluons might collide with the mass-giving particles around up and down quarks and make the mass-giving particles more dense.Perhaps in a denser region of mass-giving particles more mass-giving particles have a close enough range to
    interact with the quarks and leptons to "cause" mass.In this case because the small constant in (1 -v^2/c^2 +constant)^1/2 can make the mass of a particle like an electron 10^19 times greater (at the speed of light)then this would mean that there would be at least 10^22 mass-giving particles in the space around a neutron (which has 1000 times more rest mass).A typical three solar mass black hole has (using the small constant theory) consists of 10^57 neutrons.So there would be a minimum of10^57 x 10^22 = 10^79 mass-giving particles in 10^-45 m^3 (using a sphere of radius 10^-15 metres for the entire mass content of the hole).This is a minimum of 10^124 mass-giving particles per cubic metre.And this minimum density would have to exist throughout space because a black hole could form anywhere in space and would possess the same mass wherever it formed.
    In the universe as a whole with its radius of 10^26 metres this would mean at least (10^26)^3 x 10^124 mass-giving particles = 10^202.
    Quite a lot!
    These particles would probably be bosons so they don't give each other mass
    and make the total mass of the universe greater than 10^52 kg - its actual value (I am using the idea that bosons like to be in the same part of space
    whereas fermions do not and would interact with one another if mass-giving particles were fermions).
     
    Last edited: Aug 8, 2004
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