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How fast are we moving?

  1. Jun 11, 2013 #1
    If there was a center of the universe, unmoving, how fast would we (person on the Earth) be moving relative to it?
  2. jcsd
  3. Jun 11, 2013 #2

    Vanadium 50

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    But there isn't a center of the universe.
  4. Jun 11, 2013 #3
    impossible for such a thing to exist
    (an unmoving center point of the universe)

    speed of movement is always relative to something else so as we move in relation to a point so does that point move in relation to us so the centre would be moving (in relation to us) if there was a fixed center which there is not

    wherever you are is the center (from your viewpoint) and you cannot escape that viewpoint no matter where you go

    if there was only one quanta in the universe it would not be possible for it to have speed or movement as there would be nothing to measure its movement against

    you have asked a non question

    that is my opinion
  5. Jun 11, 2013 #4
    Our visibility of the universe is limited to the light that has reached us, for now the idea that there is no center is the most prominent, nevertheless there is the possibility that there might be an origin point.
  6. Jun 11, 2013 #5


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    The "origin point" is everywhere.
  7. Jun 11, 2013 #6
    If the dimensions of the universe are finite/un-countably finite than there must be a spatial center. If not, than the dimensions of the universe would be infinite.
  8. Jun 11, 2013 #7


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    Not true. Geometrically, it just means that space is curved like a racetrack. Go far enough in one direction and you end up back where you started.
  9. Jun 11, 2013 #8


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    That makes absolutely no sense. First of all, in GR, the dimensionality of space-time solutions (as a manifold) is 4. The universe itself (the spatial slices) is of dimension 3. It is nonsensical to call a dimension countably finite or uncountable as this applies to sets not single numbers. There is no center of the universe under the assumption of spatial homogeneity, simple as that.
  10. Jun 11, 2013 #9
    ah yes thx
  11. Jun 11, 2013 #10


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    As noted, we can't determine our speed relative to something that does not exist. But we can measure it relative to the Cosmic Background Radiation afterglow of the Big Bang. About near 400 km/sec (800,000 mph) or over 0.1% the speed of light, according to reliable sources, in the direction of the constellation Leo and towards the Great Attractor (q.v.) as we rotate about Earth's center, which rotates about the sun, which rotates about the Milky Way's Black Hole center, which rotates about the Local Group. Lot's of spinning and movement going on. And yet on a calm day, nary a leaf is swaying...it's all so relative, you know....
  12. Jun 11, 2013 #11


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    get a copy of Monty Python's Meaning of life and listen to the "Universe Song" That will tell you how fast we are moving relative to a lot of different places - and one is named "Galactic central Point". That might satisfy, but it is only the centre of our galaxy, not the whole universe.
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