Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Cosmological expansion question

  1. Apr 30, 2010 #1
    I am working off the premise that:

    If Cosmological expansion is really occurring a redshift (as we currently observe) can only be obtained if (stars, planets, atoms) do not expand.

    See Misner, Thorne and Wheeler comment:
    "Only later does he realize that the atom does not expand, the meter stick does not expand, the distance between the sun and earth does not expand. Only distances between clusters of galaxies and greater distances are subject to the expansion. No model more quickly illustrates the actual situation than a rubber balloon with pennies affixed to it, each by a drop of glue. As the balloon is inflated the pennies increase their separation one from another but not a single one of them expands!" [MTW, 1997, p.719].

    I am looking for math or physics to justify this belief.

    Thany you.
  2. jcsd
  3. Apr 30, 2010 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    http://www.lightandmatter.com/html_books/genrel/ch08/ch08.html#Section8.2 [Broken]

    See subsection 8.2.5.
    Last edited by a moderator: May 4, 2017
  4. Apr 30, 2010 #3
    Thank you for the link, I read the page and it does clear up some things, but brings up another question.

    1. I don't see where they give the cause or the supporting data that universal expansion is not occuring.
    Brooklyn may be expanding and if so it would not produce a red shift under the current theories.


    Barry Parker stated and John Peacock agreed that:
    The redshift of galaxies exists because their light waves are stretched as space is stretched, and therefore their wavelength is increased"

    If the expansion of space-time causes light waves to belengthened, why would atoms be excluded from this expansion?

    There must be something that locally overcomes this expansion if Space-Time is truly expanding.

    The article basically seems to say it is not because it cant.
    Last edited by a moderator: May 4, 2017
  5. Apr 30, 2010 #4


    User Avatar
    Science Advisor

    There's a bunch of references listed at the end of this entry from the Usenet Physics FAQ, you could check some of those for the math.
  6. May 1, 2010 #5


    Staff: Mentor

    The "something" that locally overcomes the expansion is the electromagnetic force and the strong and weak nuclear forces.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook