Dark Energy, Universe Expansion question

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bad_drawing

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As an artist...I'm a far cry from a physicist, which is why I've got this question. I'm sure this is figured into all the theories and models, and but I'd just like somebody to set me strait so I can sleep at night.<br /><br />Scientists observe that the universes is not only expanding, it is accelerating. This is shown by our observatories in orbit and on earth that can peer ever farther into space. Dark Energy (a repulsive force at work that drives things apart on cosmic scales) was put forth to explain it. <br /><br />When we look further and further away, we look back further and further in time. i.e. we look closer to the time of the big bang when the universe was still expanding from its burst into existence and gravity hadn't had time to apply the brakes much yet. So wouldn't what we observe at great distances appear to be accelerating the farther back in time we look? <br /><br />Summary: Could we actually be seeing the early, more rapid expansion of the universe when we observe distant space accelerating as opposed to dark energy currently causing it to accelerate? Does this make sense?<br /><br /><br />Thanks in advance for setting me straight.<br />
 
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alokmohan

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Cant see.Dark energy or no dark energy we may see upto a limit called visible univrtse.
 
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emperor_of_localgroup

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@bad_drawing:<br />Interesting point though. Any explosion (or whatever they think the bigbang is) makes fragments at first accelerate and then becomes steady. So, you are expecting these galaxies to eventually slow down and have steady motion in the future, long after bigbang. But I think until 90s we observed a steady motion of the galaxies (am I right on this?), but now we see an acceleration. That violates normal scientific laws. <br /><br />Another point, some closer galaxies (that means light received long after big bang) are also seen accelerating. <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>
 
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alokmohan

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Debateable.Hubble saw some far off galaxies accelerating at much greater distance.That was in 1997.
 
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emperor_of_localgroup

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@alok<br />I think you are mixing up two things, Hubble the man and Hubble the telescope. Hubble the man in early 1900 observed the galaxies are moving away from us, predicting an expansion of the universe, the so called balloon or baking cake model. I think he assumed constant velocity in his Hubble's Law. But in the 1990s, Hubble the telescope (or other scopes) found the galaxies are moving with acceleration, and hence we got dark matter and dark energy.<br /><br />The problem may also be astronomers present assumption that the gravity is the only controlling force in the 'super space' (intergalatic and intersteller space). Gravity may be the dominant force but there may be other factors involved. Who knows. <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>
 
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