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Attraction and repulsion of e- and p+

  1. Mar 22, 2009 #1
    I would like to know if electrical charge is the only way to explain attraction and repulsion of e- and p+.
     
  2. jcsd
  3. Mar 22, 2009 #2

    malawi_glenn

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    yes

    but, you can also imagine the Pauli Principle making up a "repulsive force". Consider e.g. degenerate matter, such as white dwarfs, metals, H2 molecule etc.
     
  4. Mar 22, 2009 #3
    could you explain e.g. degenerate matter.
     
  5. Mar 22, 2009 #4

    malawi_glenn

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    It is better for you to google it, and then ask more specific questions:

    http://en.wikipedia.org/wiki/Degeneracy_pressure

    http://www.wisegeek.com/what-is-degenerate-matter.htm

    http://www.daviddarling.info/encyclopedia/D/degenerate_matter.html

    http://www.123exp-science.com/t/01554105619/ [Broken]

    http://www.sfu.ca/~boal/390lecs/390lec28.pdf

    e.g. means "exempli gratia" = latin for "for example"

    scientific language often uses these abbreviations (http://en.wikipedia.org/wiki/List_of_Latin_phrases )

    i.e. and c.f. is together with e.g. the most used ones
     
    Last edited by a moderator: May 4, 2017
  6. Mar 22, 2009 #5
    does it means that in degenerate matter like dwarf stars two e- can attract ?
     
  7. Mar 22, 2009 #6

    malawi_glenn

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    No I said that the pauli principle can make up a REPULSIVE 'force' ....

    i.e you can have both repulsion from electric force and the pauli principle
     
  8. Mar 22, 2009 #7
    But I read in your internet links that electrons can fuse in neutron stars of course at very high pressures and temperatures. Do you know if ITER experiments reaching these very high temperatures will be close to these extrem conditions ?
     
  9. Mar 22, 2009 #8

    malawi_glenn

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    this is simplified:

    white dwarfs are degenerate matter of electrons, protons and neutrons, recall that the pauli principle are between IDENTICAL fermions.

    in neutron starts, the gravity force is stronger than the degenerate pressure for the mixture of electrons, protons and neutrons, so the electrons will be fused into the protons -> making up more neutrons, so that in the end you have body of only neutrons.

    if the gravity force is even stronger, so that it is stronger than the degenerate pressure between neutrons, then you will get a black hole...

    Now temperature is no the only interesting thing. ITER will not, as far as i know, have such a high density that degeneracy effects will emerge.
     
  10. Mar 22, 2009 #9

    malawi_glenn

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    It is also really fun that a professor in physics, which call himself scientist expert, don't know what degenerate matter is ;-)
     
  11. Mar 22, 2009 #10
    you can not be expert in every things I am expert in non newtonian fluids mechanics and heat transfer but I never worked on these cosmological theories. I can give you the shear rate value in a plate heat exchanger because I do many experiments and I perfectly measure pressure drops, flow rate and viscosities but I never been in neutron stars to se what it happens with electrons protons and neutrons. I am sure you never measure it also :-)
     
  12. Mar 22, 2009 #11

    malawi_glenn

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    degenerate matter is basic quantum physics :-p

    so how can you claim you have a quantum theory of gravity if you don't even know basic quantum physics?

    anyway, why did you ask "But I read in your internet links that electrons can fuse in neutron stars of course at very high pressures and temperatures"?? If there is something you don't understand about degeneracy pressure, ask it.

    I doubt that in 20min you could read all the links I gave you.

    And one does not have to be inside a neutron star to measure these things.. we can observe it by means of telescopes etc.
     
  13. Mar 22, 2009 #12
    why gravity becomes so high in neutron stars ? even if I am not a specialist of cosmology, and considering the huge amount of paper I published 15 years ago I think I have good rest and I am sure you find my questions interesting :-)
     
  14. Mar 22, 2009 #13

    malawi_glenn

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    The gravity is from the initial star, the higher mass it had, the higher the gravity field in its centre. So when the star collapse when its central nuclear fusion halts, it will (very rapidly, faster than 1 second) shrink (there is no outward radiation pressure from the centre that can overcome the inward directed gravity force). First the star will become a white dwarf, but if the gravity force still is greater, it will pass this stage (very very quick) and become a neutron star. And if the gravity is even stronger, it will pass and become a black hole.

    http://www.ast.leeds.ac.uk/~knapp/StarFates.pdf [Broken]

    http://www.studyphysics.ca/sci30/fate.pdf


    I don't think your questions are interesting, well maybe for a freshman in physics... ;-)

    And this is not cosmology, it is astrophysics.
     
    Last edited by a moderator: May 4, 2017
  15. Mar 22, 2009 #14
    of course I know all of these things but sometimes you have to ask the false to know the true :-)
    I am also a good mathematician playing with differential geometry since 20 years mainly for fluid mechanics applications. And I used Elie CARTAN mathematical support to extend GR equations to infinitely small systems.
    You know we have to be modest simply because it is difficult to measure things at these scales and to medelize them. In fluid mechanics we are using dimensionless numbers to overcome scaling problems then for atomic and astronomic theories...
     
  16. Mar 22, 2009 #15

    malawi_glenn

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    sure, whatever...
     
  17. May 15, 2009 #16
    malawi_glenn and delplace,

    You're both experts in your respective fields. Can you please both demonstrate your professionalism by refraining from guttersnipe attacks? I am looking for knowledgable professionals to consult with. So please act accordingly.
     
  18. May 15, 2009 #17

    jtbell

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    They stopped almost three months ago. :uhh:
     
  19. May 15, 2009 #18
    It doesn't excuse such bad behavior.
     
  20. May 15, 2009 #19
    More specifically, I expect highly intelligent professionals (generally and broadly) to act like ladies and gentlemen; not like troubled teen agers. Or maybe we should start grounding badly behaved physicists and send them to their room without dinner?
     
    Last edited: May 15, 2009
  21. May 16, 2009 #20

    malawi_glenn

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    if you have trouble with this, you can report the posts by hitting the "report" button.

    delplace is not a professional in this field, he was working with milk or something like that when some science advisor checked him out

    I am almost a teenager so? :tongue:
     
  22. May 16, 2009 #21
    I was grumpy (butthead girlfriend) and failed to notice the ";)". I also completely missed the "milk professional occupational ... study...research...".

    Please forgive my occasional propensity to be the back end of a horse. I am sure my girlfriends (past and present) still refer to me that way.
     
    Last edited: May 16, 2009
  23. May 16, 2009 #22

    malawi_glenn

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    me and delplace also had discussion going on in like 5 threads simultaneously, and private communication. He was a real "joker", he said many stupid things like that he meet the Swedish government to discuss who would get Nobel prize etc.

    (but the Swedish government has nothing to do with the Nobel Prize)

    He was a jerk who lied and also said many times that he is the professor and I am the student, I never said anything rude but always ended my sentences with a smiley ";-)" to make sure that no confusion could be done. If you end up a sentence that seems to be rude, with a ";-)", it means that you are ironic and is joking - I am Swedish and actually the most common form of humour here is ironic and sarcasm :-p :-D
     
  24. May 16, 2009 #23
    I know I need to get eyeglasses. I've been procrastinating for the last 20 years. It's amazing I haven't run over any pedestrians. Maybe you should make your smiley face larger? ;-)
     
  25. May 16, 2009 #24

    malawi_glenn

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    HAHA yeah :tongue: :rofl:
     
  26. May 16, 2009 #25

    Vanadium 50

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    Freddie, you asked for this to stop. JTBell points out that it stopped months ago. Accept that you've got what you asked for, and for heaven's sake move on!
     
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