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Splitting a Photon

  1. Apr 16, 2008 #1
    I am not that knowledgeable about physics..... Correct me if I am wrong and I probably am.....Ok If we split a Photon ( I am 90% sure I am talking about Photons) then take the two pieces and separate them they have the same charges, positive or negative. We then can take electricity and change the charge on one and the charge on the other will change, no matter how far they are separated, Am I correct ? If not and I am talking about something 100% completely different, please tell me.

    If the above is true, what do you need to split one, change the charge and determine the charge.

    Thanks for any and all help, Again I apologize for any wrong information I provided and I look forward to corrections
  2. jcsd
  3. Apr 16, 2008 #2


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    a photon is a point like particle with no internal stucture so it cant be splitted.
  4. Apr 16, 2008 #3
    Hey, what about a muon !? :smile:
  5. Apr 16, 2008 #4


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    you need a very sharp knife :-)

    muon -> electron + electronantineutrino + muonneutrino

    EDIT: Yes Iam aware that mouns are pointlike particles too, and that pair production exists
    Last edited: Apr 16, 2008
  6. Apr 16, 2008 #5
    But is it not pointlike without substructure !? Am I out of my mind right now !? (very possible)
  7. Apr 16, 2008 #6


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    I wanted the OP to rephrase or reconsider his question, thats all :-)
  8. Apr 16, 2008 #7
    Ah, for a while I was wondering if the muon was not pointlike anymore !
    Pfiou... :rolleyes:
  9. Apr 16, 2008 #8


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  10. Apr 16, 2008 #9
    Could it be that he was talking about a proton instead of a photon?
    Is he talking about quantum entanglement?
  11. Apr 16, 2008 #10
    I am not a physists, I am just pondering something that someone was talking about while high....I am normal now though and it still sounds like a good idea....
    so if you split a proton and change the charge of one piece does the charge of the other piece change as well? does any atomic partical thingy mer bob do that???
  12. Apr 16, 2008 #11
    *Edit: I got my story mixed up a bit, just setting it straight.

    You've gotta watch those high fellas; I had one swearing up and down that Tesla invented AC because he wanted something "safer" than DC. Apparentely DC kills you because once it gets inside of you it has nowhere to go. :rofl:

    Anyway, what you're thinking of is Quantum Entanglement, in which the spin of two spatially separated particles becomes entangled. I'll save you the gooble-de-gock, basically it boils down to this: When we measure one of two entangled particles, it randomly will have either spin of "X" or "Y," and because of some properties of the particles, this means the other particle has what is left (if we measure particle A and it has a spin of X, then particle B has a spin of Y, and vice versa.)

    Most people think that this violates Relativity because the spin of the particles collapses instantly (the MOMENT we measure particle A, particle B gets whatever spin is remaining.) Special/General Relativity states that information cannot travel faster than light. Since we have no control over the spin of the particle we measure, we can't use it to send information, and no laws are broken.

    That's a very, VERY basic summary.
    Last edited: Apr 16, 2008
  13. Apr 16, 2008 #12
    After talking to my friend who had just watched Genius (1999) videoDOTaolDOTcom/video-detail/disney-genius-part-8/3059166757 about 7 minutes 30 second about geneva convention splitting a proton and what one does the other does

    Ok finding out the date and circumstance my friend was talking about, I googled arround a bit and came up with this

    The Year in Science: Physics 1997
    Score One (More) for the Spooks
    by Robert Pool

    Einstein would not have been amused. Not only did researchers demonstrate last May a phenomenon that the Great One once disparaged as spooky action at a distance, but they proved it happens even at great distances. Worse, they performed the experiment in Switzerland, not far from the patent office where Einstein worked in 1905—the year he explained the quantum nature of light, which laid the foundation for quantum mechanics, which he later found so maddeningly spooky.

    The spooky action in question involves a voodoolike link between two particles such that a measurement carried out on one has an instantaneous effect on the other, though it be far away—nearly seven miles away, in the experiment done by physicist Nicolas Gisin’s team at the University of Geneva. Gisin and his colleagues borrowed fiber-optic phone lines running from Geneva to two nearby villages. In Geneva, they shone photons into a potassium-niobate crystal, which split each photon into a pair of less energetic photons traveling in opposite directions—one north toward Bellevue and the other southwest to Bernex. At these two destinations, nearly seven miles apart, each photon was fed into a detector.

    Common sense would suggest that nothing done to the photon in Bellevue could affect the photon in Bernex, or vice versa, but quantum mechanics never had much to do with common sense. For starters, the uncertainty principle says that Gisin cannot simultaneously know both the energy of a photon and the time it left the crystal in Geneva, at least not precisely. Furthermore, quantum mechanics insists that the photons don’t have precise properties until they are measured. To show what he saw as the absurdity of the claim, Einstein proposed a simple thought experiment in 1935, and this became the basis for Gisin’s complicated real one.

    Einstein believed that the uncertainty principle was just a measurement problem, not a reality problem. His idea, in terms of the Geneva experiment, was that you could learn the energy of one photon by measuring the energy of the other one far away; by the same token, you could learn a photon’s arrival time by measuring that of its distant counterpart. After all, the two photons had to leave Geneva at the same time, and although their energies might not be equal, they have to add up to the energy of the parent photon. Assuming that these measurements could be made, and that they added up in this commonsense way, Einstein would be correct, and reality would be independent of measurement. Or you’d be forced to argue that the Bellevue measurement instantaneously and spookily changes the reality of the photon at Bernex, which to Einstein was an absurd suggestion. The mind game itself was proof enough for Einstein, but in 1964 physicist John Bell turned it into a testable hypothesis. He came up with an equation, called Bell’s inequality, that boiled the question down to a set of measurements of many photons hitting detectors. If energy and arrival time were absolute values, as Einstein believed, then these measurements would be true to Bell’s inequality. If, on the other hand, quantum mechanics was valid after all, and the precise energy and arrival time of a photon did not exist until they were measured, the measurements would violate Bell’s inequality.

    In Gisin’s experiment, alas, Einstein and common sense were the losers. It’s as if he had flipped a coin at Bellevue, Gisin says, while his colleague had flipped one at Bernex, and each time he grabbed his coin out of the air and saw it was heads up, his colleague’s coin had simultaneously stopped spinning and landed heads up as well. And this happened thousands of times in a row. It is a very strange prediction, Gisin says, and because it is so bizarre, it deserved to be tested.

    In fact, it had already been tested many times, most notably in 1981 when physicist Alain Aspect from the University of Paris first dazzled his peers by demonstrating the phenomenon. But Aspect separated his photons by only a few meters, and since then some physicists who share Einstein’s reluctance to abandon common sense had speculated that the spooky effect might decline with distance. We have now done it in the lab, and we have done it at 10 kilometers, and we found no significant differences, Gisin says. Common sense, at least in the quantum world, would seem to be a dead horse—but Gisin is planning one more crack at the corpse. He wants to set up a test at an even farther distance—perhaps the 60 miles that separate Geneva and Bern, the site of the patent office where Einstein worked. He even knows when he wants to do it: in 2005, the centennial of Einstein’s pioneering paper.


    Now me being high at the time and working on home work thought of this idea
    For an Unconditional 100% hack proof tap proof network connection
    Say you get two sets (Set A,a/ Set B,b; lower case means sender, upper case receiver)
    Build two boxes and take Ab in one box and Ba in the other. So when you measure A in box 1, a changes in Box 2. Correct??? well think of morse code I mean this could solve communication issue in space and long distance..... well thats my thoughts feed back?
  14. Apr 17, 2008 #13

    Maybe you missed the last part of my other post. We -cannot- use entanglement to send information faster than light. Einstein wouldn't be happy because entanglement strongly supports the Copenhagen Interpretation of the wave function, NOT because it violates his Relativity. According to the Copenhagen Interpretation of the wave function, the given particles do not have a measurement of spin until they are actually measured. Once measured, the particle can take one of the many spin values available, but it does so in a completely arbitrary fashion. There is no physical way to predict which spin value the particle will have when measured.

    Einstein hoped to prove that this interpretation would violate causation via faster than light travel, but other Scientists showed that no information is conveyed so no laws are broken. Einstein had his cake, but it seems to have been made of wax.

    * On second thought, I believe this also applied to determinism and Heisenberg's Uncertainty Principle. Hopefully someone else will clarify, I'm not the world's foremost expert on these things. ;p
    Last edited: Apr 17, 2008
  15. Apr 17, 2008 #14
    Are you sure you don't mean a proton?

    Photons do not have a charge.

    EDIT: Ah! You mean Proton.
  16. Apr 18, 2008 #15


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    Albeit somewhat indirectly, I believe that one could "split" a photon. That is, let a heavy charged particle absorb a photon, then radiate two photons. With a massive charge, the outgoing photons will have energies that add to the initial photon energy. It also might be possible to have an atomic cascade do much the same thing.
    Reilly Atkinson
  17. Mar 7, 2010 #16
    This one really irritates me, too :)

    According to one school you can't split a photon. As you say it's a pointlike particle, no mass, no size, energy yes, momentum yes. According to "B. E. A. Saleh and M. C. Teich, Fundamentals of Photonics (Wiley, 1991)". "Experiments confirm that the photon is not a short pulse of electromagnetic radiation; it does not spread out as it propagates, nor does it divide when it encounters a beam splitter"

    But then there are dome pointing to Feynman and 'many paths' saying that ¨'of course you can split a photon as it takes several paths simultaneously' "Actually, it is possible to split a single photon and have it interfere with itself. Mathematically if a photon has two paths that it can follow it follows both."

    Can both be correct?
  18. Mar 7, 2010 #17
    Protons were first split at SLAC (Stanford Linear Accelerator Center) about 1970 by Friedman Kendall and Taylor, and they found three particles, later named quarks.

    Bob S
  19. Mar 8, 2010 #18
    Perhaps the caption should be changed :)
    Just as a thought?

    Splitting a -Proton-?
    In the interest of spelling?


    Thanks for that clever answer btw ::))
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