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Proton electron mass ratio

  1. May 3, 2006 #1
    There was a recent article in nature on how there was "INDICATIONS OF A CHANGE IN THE PROTON-TO-ELECTRON MASS RATIO have shown up in comparisons of the spectra of hydrogen gas as recorded in a lab with spectra of light coming from hydrogen clouds at the distance of quasars. "

    I was just wondering how ture people think this is.
    Could this constant really be changing?
  2. jcsd
  3. May 3, 2006 #2


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  4. May 3, 2006 #3


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    As with the purported claim of the changing fine structure constant with time, these things need to be verified independently using a different method to be convincing.

  5. May 4, 2006 #4


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    and, to repeat from older threads, it is these dimensionless "constants" that count. if [itex]m_e/m_p[/itex] changes or if [itex]\alpha[/itex] changes, that means something. claims made about a changing [itex]c[/itex] or [itex]G[/itex] are meaningless. we can only measure these quantities against like dimensioned standards (like a carpenter measuring length with a tape-measure) and we measure or ultiimately sense only dimensionless quanitities. if something has noticeably changed, it was a ratio of like dimensioned quantities and to blame that change on any single dimesionful component (like blaming it on [itex]m_p[/itex]) is misleading.

    so at least the OP is inquiring about a meaningful issues.
    Last edited: May 4, 2006
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