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  • Astronomy, astrophysics question

    This is an article about a new way to calculate astronomic distances that may change the accepted Hubble Constant by 15%.

    A project aiming to create an easier way to measure cosmic distances has instead turned up surprising evidence that our large and ancient universe may be even bigger and older than previously thought.


    This is what struck me:
    ...
    Scientists now estimate the universe to be about 13.7 billion years old (a figure that has seemed firm since 2003, based on measurements of radiation leftover from the Big Bang) and about 156 billion light-years wide.

    The new finding implies that the universe is instead about 15.8 billion years old and about 180 billion light-years wide.

    ...

    How could the universe be ~15 billion years old, but ~150 billion light years wide?
    Doesn't that imply that the average rate of expansion is an order of magnitude greater than the speed of light?

    Admittedly my detailed astrophysics knowledge dates from 1975, but on the face of it this sounds impossible.
    Anyone know what gives?
    Chuck
    秋音的爸爸

  • #2
    Yes, the rate of expansion "is" (somehow...) order of magnitude greater than the speed of light. No, this doesn't violate Einstein's physics. Simply because the space itself expands.

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    • #3
      According to current theory, the universe reached 90% of its current size before Einstein kicked in, in just the first few hundred thousand years of its existence.



      Kevin

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      • #4
        WMAP = Wilkinson Microwave Anisotropy Probe, a 2001 probe to ameasure the distribution of the cosmic background radiation ( http://en.wikipedia.org/wiki/WMAP ) and thereby get a read on the conditions after the 'big bang'.

        Last edited by Dr Mordrid; 8 August 2006, 21:02.
        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

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        • #5
          What is to say there are not multiple "universes?" Brings you back to that question you would always ask as a kid - how can space never end? and if it does end, what is beyond that - wouldn't it just be more space? And then if so - why not more "universes" in it? I think they should redefine universe.
          Q9450 + TRUE, G.Skill 2x2GB DDR2, GTX 560, ASUS X48, 1TB WD Black, Windows 7 64-bit, LG M2762D-PM 27" + 17" LG 1752TX, Corsair HX620, Antec P182, Logitech G5 (Blue)
          Laptop: MSI Wind - Black

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          • #6
            According to M-Theory (M variously = Magic, Membrane ['brane for short] or Matrix) there is a multitude of universes, a 'multiverse', contained in 11 dimensions: 10 spatial + time.

            NOVA's 'Elegant Universe' online (3 hrs) does a fair job of putting it into English;

            http://www.pbs.org/wgbh/nova/elegant/program.html (small frame QT/RM segments)

            http://www.pbs.org/wgbh/nova/elegant/program_d.html (full screen QT/RM segments)

            Check out the parallel universes segment (5 min)
            Last edited by Dr Mordrid; 9 August 2006, 00:06.
            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

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            • #7
              It's a donut! Astrophysicists are expecting or trying to explain why the universe isn't acting like a spherical bubble by using Dark Matter, which has never been observed.

              The big bang occurred at the center of the donut and flat space is following the surface of the donut. Eventually it will travel completely around and collapse again.



              Kevin

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              • #8
                Originally posted by |Mehen|
                What is to say there are not multiple "universes?" Brings you back to that question you would always ask as a kid - how can space never end? and if it does end, what is beyond that - wouldn't it just be more space? And then if so - why not more "universes" in it? I think they should redefine universe.
                It's a bit pointless asking what's beyond...you can't get there anyway, and also no information (and I mean - not in practical sense, but in theoretical physics sense)

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                • #9
                  Originally posted by KRSESQ
                  It's a donut!
                  In the Simpsons episode with Stephen Hawking, there is moment where Hawking is at Moe's bar with Homer, and he states: "Homer, I may have to steal your idea of a donut-shaped universe".


                  Jörg
                  pixar
                  Dream as if you'll live forever. Live as if you'll die tomorrow. (James Dean)

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                  • #10
                    Originally posted by KRSESQ
                    It's a donut!
                    Dodecahedron?

                    Explore National Geographic. A world leader in geography, cartography and exploration.


                    ESA's Max Planck probe should give cosmic background radiation data with enough resolution to say which shape the universe really is. Planck launches Q1 next year if all goes well;

                    Last edited by Dr Mordrid; 11 August 2006, 11:23.
                    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

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