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jesse robb

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Help! Are we really expanding?

how could all of the galaxies Hubble saw have been moving away from him in every direction?

If we look forward they should be moving away, but if we look back into the big bang, shouldn't they being moving toward us?

And if we are also moving at the same increasing speed how can there be redshift at all? wouldn't everything appear static, as if we were on an airplane ?

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    Henk Mulder 10+

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    Aug 8 2012: Take balloon and mark it with a lot of dots. Now blow it up and as it expands you'll see all the dots moving away from each other. This only happens with an expanding surface.

    Be careful, if you blow too much, there will be a big bang.

    • jesse robb

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      Aug 9 2012: so the fabric of space (balloon surface) is expanding and the galaxies are just along for the ride? does that mean there is a connection between the galaxies and balloon surface?
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        Henk Mulder 10+

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        Aug 9 2012: The balloon experiment is just an analogy which illustrates the increasing distance between galaxies etc. But here it stops.

        The problem with the Big Bang is that space itself was created and it is space itself that is expanding. For reasons I don't fully comprehend, and i'm not sure anyone does, the universe has no center nor does it have an edge. This is because we are not expanding in space but space it expanding itself.

        Add to this the little complexity of the size of the universe. It is so big that light from distant galaxies travels so far that we are not seeing these galaxies as they are today, but as they were when the light left them, sometimes billions of years ago. So, not only is space expanding, time is also a stretchy mess, at least from where we stand.

        Most physicists have stopped trying to visualize the cosmos, sub-atomic space and quantum mechanics. Instead they have models that are coherent within that context and they visualize those. The human brain is at present not really capable of visualizing 4+ dimensional space-time, which is what these extreme environments are made of. It's fun trying though :o)

        • jesse robb

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          Aug 10 2012: right, I got the analogy and I know about everything you said. I like you am just trying to comprehend where who and why we are.

          It's an addiction to say the least.. or an escape perhaps.

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