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Motion of the Primordial Universe Revealed

Posted by michael on from the hot-and-bothered dept.

neutron_p writes "New results from an instrument located high in the Chilean Andes (the Cosmic Background Imager) are giving researchers a clearer view of what the universe looked like in the first moments following the Big Bang. Cosmologists observe a time in the universe's distant past when atoms were first forming. The findings reveal the first movements between these "seeds" that ultimately led to clusters of early galaxies."

3 of 63 comments (clear)

  1. More information by TMB · · Score: 3, Informative

    The press release at the CBI website is much more informative.

    The big news is that they've measured the polarized power spectrum, and it agrees extremely well with the theoretical predictions. Which means that not only do the density fluctuations match what's expected, but the matter is moving in the gravitational field of those density fluctuations exactly as expected.

    [TMB]

  2. Re:This has always confused me by Zaak · · Score: 3, Informative
    ...the universe would have to have expanded at several times the speed of light in those first 400,000 years...

    Yes. During inflation the universe expanded not at several times the speed of light, but rather doubled its size every 10^-34 of a second. After about a hundred doublings the inflationary period ended and expansion slowed to (locally) sub-light speeds.

    The microwave background didn't come from the big bang though. It was actually emitted from the surface of last scattering when the universe became transparent for the first time--around 300k years after the big bang.

    ...we'd have to be sitting at pretty close to the center of the universe...

    The "center of the universe" is not well-defined. If the universe is topologically closed, then it has neither center nor boundary, like the surface of the earth. If the universe is topologically open, then it is infinite in size and similarly has neither center nor boundary.

    TTFN

  3. Re:This has always confused me by Zaak · · Score: 3, Informative

    Pardon me but if the universe expanded in such a manner wouldn't that be against the theory of relativity. What about breaking causality?

    Well IANAP, but I'll explain what I understand of it.

    Relativity requires that no signal can travel faster than the speed of light. During inflation, nearby parts of the universe move away from each other faster than the speed of light. However, because there is no signal traveling FTL, causality is not violated.

    TTFN