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Planck Photon

  1. Feb 24, 2005 #1

    [tex]\gamma (E_1) \rightarrow e^+ + e^- \; \; \; E_1 = 2 m_e c^2[/tex]
    [tex]\gamma (E_2) \rightarrow p^+ + p^- \; \; \; E_2 = 2 m_p c^2[/tex]
    [tex]\gamma_p (E_3) \rightarrow m_p^+ + m_p^- \; \; \; E_3 = 2 c^2 \sqrt{\frac{\hbar c}{G}}[/tex]

    [tex]E_n[/tex] - photon energy
    [tex]\gamma_p[/tex] - Planck Photon
    [tex]m_p^+[/tex] - Planck mass (matter)
    [tex]m_p^-[/tex] - Planck mass (anti-matter)

    Given that reaction 1 and 2 are possible when energically feasable, is reaction 3 possible if energically feasable?

    Can a 'Planck Photon' exist at the dual Planck Energy threshold?

    If possible, what type of unifying principle would such a reaction represent?

  2. jcsd
  3. Feb 25, 2005 #2


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    The question is, if such concentration of energy in a small region of space will blackhole itself out.
  4. Feb 25, 2005 #3


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    Is there such a thing as a "Planck mass" particle?
  5. Feb 25, 2005 #4


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    I've never heard of one. I mean Planck's mass is heavy on the atomic scale. I don' t think there is. Maybe I'm wrong....
  6. Feb 27, 2005 #5
    Planck Particle...

    I suppose a hypothetical formula is required to determine if a Planck mass is 'stable'. What is the equation formula that could determine Planck mass 'stability'?. Is Planck mass 'stable'?

    A 'particle' sized Planck mass can exist, but a Planck mass 'particle' cannot exist?

    If a Planck mass 'particle' can 'exist', what family and class of known conventional particles would it most closely resemble?

    Which conventional 'particle' does it most closely resemble?
  7. Feb 27, 2005 #6


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    I'm abit confused with what your asking, but isn't the Planck mass around the mass of a flea? I'm saying that there is no atomic particle that has such as mass. Am I wrong?
  8. Feb 27, 2005 #7
    I think what DB is trying to say is that the planck mass is about
    [tex] 10^{-8} kg [/tex]
    while atomic masses are on the order of
    [tex] 10^{-26} kg [/tex]

    So something of planck mass would probably obey macroscopic laws. And talking about it as a fundamental particle is a little odd.
  9. Feb 27, 2005 #8
    For arguments sake the Energy of the Planck Photon mentioned above is about
    [tex] 10^{10} GeV [/tex]
    Where would a photon of this energy come from?
  10. Feb 28, 2005 #9
    I'm confused. I thought "plank scale" stuff was supposed to be really small. So is a plank "thing" the smallest quantity of that "thing" you can measure/have?
  11. Feb 28, 2005 #10


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    Entropy, the point is that mass is inverse of distance, via x=h/mc
    So Planck stuff has small size, high mass, high energy. Or, the most energy (mass) you put, the more resolution you have. Electron microscopes having more resolution than optical microscopes &c.
  12. Feb 28, 2005 #11
    Off topic, but what happens when an EM wave (or photon or whatever) has a frequency wayyyyy beyond the gamma ray and radiowave region. What would it be? What kinda properties would it have?
  13. Feb 28, 2005 #12
    the highest photon observed is ~10^20 eV, and theoretical physics set no upper limit on energy of photon....
  14. Feb 28, 2005 #13
    Do you have a reference for this?
  15. Mar 1, 2005 #14
    Planck Particle...

    If Planck mass obeys macroscopic laws, and only microscopic particles obey De-broglie waves, then it must be stated that:

    Macroscopic Law:
    [tex]r_p > \overline{\lambda_p}[/tex] - Planck radius greater than Planck-De Broglie wavelength

    Microscopic Law:
    [tex]r_p = \overline{\lambda_p}[/tex] - Planck radius equals Planck-De Broglie wavelength

    Planck Wavelength solution:
    [tex]\overline{\lambda}_p = \frac{\hbar}{m_p c} = \frac{\hbar}{c} \sqrt{\frac{G}{\hbar c}}[/tex]
    [tex]\overline{\lambda}_p = \sqrt{\frac{\hbar G}{c^3}}[/tex]
    [tex]\boxed{r_p = \overline{\lambda}_p = \sqrt{\frac{\hbar G}{c^3}}}[/tex]

    Although Planck mass appears to be a macroscopic entity, it is in fact a microscopic entity which obeys quantum laws and therefore, is a quantum 'particle'.

    - (see reference 2)

    Maxwell's equations, which the derivatives describe all electromagnetic phenomena, do not describe any theoretical limit to a photon's energy, however given that photon energy is quantizised, a possible Maxwell energy solution is:

    [tex]E_n = \frac{n \hbar}{\overline{\lambda} \sqrt{\mu_o \epsilon_o}}[/tex]

    Given that there is no theoretical upper limit to photon energy and given that Planck mass IS a microscopic quantum particle, then reaction 3 listed above IS energetically feasable (possible).

    A photon is an electromagnetic wave, and all electromagnetic waves obey the Principle of Superposition:
    For two or more photons, the resultant wave function at any point is the algebraic sum of the wave functions of the individual waves.

    Is reaction 1 possible through the Principle of Superposition constructive interference?
    [tex]\psi (E_a)_{\gamma} + \psi (E_b)_{\gamma} = 2 \psi (2E_t)_{\gamma} \rightarrow e^+ + e^- \; \; \; E_a = E_b = m_e c^2[/tex]

  16. Mar 1, 2005 #15
    Sorry, I was asking for a reference for the 10^20 eV particle, I was trying the other day to find the value for the highest energy photon observed but couldn't find anything satisfactory. I would never disagree with the photon obeying quantum laws, but it would be interesting for it to decay into these huge rest mass particles that would essentially be classical in nature. I would guess that it (the extremely high energy photon) would decay into many "quantum particles" rather than 2 essentially classical ones. It would be interesting to probe this, though I know it wouldn't be energetically feasible in the near future.
  17. Mar 4, 2005 #16
    Oh, okay, I understand now. It's related to uncertainity.
  18. Mar 4, 2005 #17
    Norman Normalization...

    Based upon the Planck Photon threshold energy, what types of 'quantum particles' would be the expected 'particle' decay products?

    What is the threshold energy for unification based upon the Standard Model?
  19. Mar 5, 2005 #18
    Planck mass is the mass which is required to collapse a Planck size volume into a black hole. QM predicts that no smaller black hole can exist. GR has no such restriction, and predicts that smaller black holes can exist in spaces smaller than the Planck volume. Perhaps we will have an answer to this question if the new collider at CERN produces miniature black holes, as some physicists have predicted.
  20. Mar 5, 2005 #19
    Sorry I must not have been thinking... a free photon has an infinite lifetime. It is a stable particle and does not have a preferred decay channel. See http://pdg.lbl.gov/ please. But if this was a virtual photon it would of course be constrained by the the conservation laws of the initial particles (ie electric charge, lepton number, etc). I am sorry but I do not understand your question about threshold energy of unification of the Standard Model. If you are asking at what energy is it projected that the strong and electroweak forces become indistinguishable, I believe it is believed this happens at about 10^15 GeV.
    I would be good to note that this(grand unification energy) has (not yet) been tested but I think it is probable based on the unification of the weak and electromagnetic forces.
  21. Mar 5, 2005 #20
    Please note my orginal post on the planck energy above was wrong. I redid the calculation since I noticed that grand unification would happen way above the planck energy and it should not, they should be close but unification is just below planck energy.
    [tex] E_p=\sqrt{\frac{\hbar c^5}{G}}=\sqrt{\frac{(1.05\times 10^{-34}) (3\times 10^8)^5}{6.67\times 10^{-11}}}=1.96\times10^9J=3 \times 10^{16} GeV [/tex]
    Sorry about the mix up. I don't know where I got 10^10 GeV...
    Last edited: Mar 5, 2005
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