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    I thought the universe is said to be expanding by galaxies accelerating away from each other and that was from the farther the galaxy is away from us the faster its moving away? but if they look further they look more into the past....so thats saying the galaxies that are seen in the past are moving away faster than the galaxies closer to the present. Basically how can they tell the universe is expanding/accelrating?
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    I reckon the anwser would probably revolve around some implementation of 'Dark Energy'. Don't know much about it though. Not sure if this is quite what you're asking either.

    Link to the Wikipedia article on Dark Energy

    Current observations suggest that the universe is still expanding.

    I'm sure someone else will be able to give a more helpful/meaningful anwser.
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    Once you look out far enough (away from locally gravitationally bound galaxies) all galaxies we see exhibit a redshifting in their light, due to the doppler effect. This is due to the fact they are moving away from us and it's due to the space between us and them expanding.

    We have evidence for this expansion accelerating, and not decelerating as you'd expect from objects linked by gravity, from the spectra of Type 1A supernova. These explosions are always the same in their pattern of behaviour. Because of this you can work out the difference in how bright the explosion is seen to how bright it was near by and via some maths work out it's distance. Using a few more formulas I don't know or have forgotten you can then work out the expansion was slower in the past!
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    o right, okies thank you.
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    The universe must be expanding because entropy always increases? Or vice versa.

    Second law of thermodynamics.
 
 
 
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