Announcement

Collapse
No announcement yet.

A disturbance in the force

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • A disturbance in the force



    So...the physical constants by which we observe the world and universe are the same everywhere, right? Apparently not - the fine structure constant, which characterizes the strength of the electromagnetic interaction, apparently varies. Just a little bit, but enough to imply new physics.

    Universe Today....

    Disturbance in the Force – A Spatially Varying Fine Structure Constant

    In order for astronomers to explore the outer reaches of our universe, they rely upon the assumption that the physical constants we observe in the lab on Earth are physically constant everywhere in the universe. This assumption seems to hold up extremely well. If the universe’s constants were grossly different, stars would fail to shine and galaxies would fail to coalesce. Yet as far we we look in our universe, the effects which rely on these physical constants being constant, still seem to happen. But new research has revealed that one of these constants, known as the fine structure constant, may vary ever so slightly in different portions of the universe.

    Of all physical constants, the fine structure constant seems like an odd one to be probing with astronomy. It appears in many equations involving some of the smallest scales in the universe. In particular, it is used frequently in quantum physics and is part of the quantum derivation of the structure of the hydrogen atom. This quantum model determines the allowed energy levels of electrons in the atoms. Change this constant and the orbitals shift as well.

    Since the allowed energy levels determine what wavelengths of light such an atom can emit, a careful analysis of the positioning of these spectral lines in distant galaxies would reveal variations in the constant that helped control them. Using the Very Large Telescope (VLT) and the Keck Observatory, a team from the University of New South Whales has analyzed the spectra of 300 galaxies and found the subtle changes that should exist if this constant was less than constant.

    Since the two sets of telescopes used point in different directions (Keck in the Northern hemisphere and the VLT in the Southern), the researchers noticed that the variation seemed to have a preferred direction. As Julian King, one of the paper’s authors, explained, “Looking to the north with Keck we see, on average, a smaller alpha in distant galaxies, but when looking south with the VLT we see a larger alpha.”

    However, “it varies by only a tiny amount — about one part in 100,000 — over most of the observable universe”. As such, although the result is very intriguing, it does not demolish our understanding of the universe or make hypotheses like that of a greatly variable speed of light plausible (an argument frequently tossed around by Creationists). But, “If our results are correct, clearly we shall need new physical theories to satisfactorily describe them.”
    >
    >
    Last edited by Dr Mordrid; 15 September 2010, 20:56.
    Dr. Mordrid
    ----------------------------
    An elephant is a mouse built to government specifications.

    I carry a gun because I can't throw a rock 1,250 fps

  • #2
    Ouch! I'm worried! :-(

    Question: is the earth a stable-enough platform from which this kind of observation can be made?
    Brian (the devil incarnate)

    Comment


    • #3
      we need stuff at the lagrange points and the moon.

      like some of the Bigelow inflatable stations.
      Convert Defense budget to that
      PC-1 Fractal Design Arc Mini R2, 3800X, Asus B450M-PRO mATX, 2x8GB B-die@3800C16, AMD Vega64, Seasonic 850W Gold, Black Ice Nemesis/Laing DDC/EKWB 240 Loop (VRM>CPU>GPU), Noctua Fans.
      Nas : i3/itx/2x4GB/8x4TB BTRFS/Raid6 (7 + Hotspare) Xpenology
      +++ : FSP Nano 800VA (Pi's+switch) + 1600VA (PC-1+Nas)

      Comment


      • #4
        Originally posted by Brian Ellis View Post
        Ouch! I'm worried! :-(

        Question: is the earth a stable-enough platform from which this kind of observation can be made?
        With the adaptive optics on modern terrestrial scopes and the large space telescopes already up and coming in the next decade these observations should be no problem.

        The huge James Webb Space Telescope goes up to L2 in a few years.
        Dr. Mordrid
        ----------------------------
        An elephant is a mouse built to government specifications.

        I carry a gun because I can't throw a rock 1,250 fps

        Comment

        Working...
        X