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Is Dark Energy for real?

  1. Apr 3, 2015 #1
    I have read a number of explanation for Dark Energy. To me, it looks like the evidence has been misinterpreted. When you look very deep into space you are looking back in time to near the beginning. It makes sense that that matter will be moving away at very high velocity and as we look closer to now, the rate of recession will be slower. It looks to me there is no Dark Energy. If I'm wrong, what am I missing in the explanation for Dark Energy?
     
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  3. Apr 3, 2015 #2

    George Jones

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    What are you missing? A quantitative analysis.
     
  4. Apr 3, 2015 #3
    Your response does not help.
     
  5. Apr 3, 2015 #4

    wabbit

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    This suggests you haven't looked at the evidence or how it is interpreted. In a word, the effect of how far back we are looking is of course taken into account, and the result of accelerating expansion is derived by careful modelling, as you would expect professionals in the field to do.
     
    Last edited: Apr 3, 2015
  6. Apr 3, 2015 #5

    George Jones

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    Also, there is more than one line of evidence, e.g., I suspect you have not looked at the acoustic peaks so exquisitely detailed by the Planck satellite.
     
  7. Apr 3, 2015 #6

    phinds

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    "Dark Energy" is a placeholder name standing in for "we don't know WHAT the hell is causing the effects that we see". The point is that the effects, dispute your misunderstanding, are very well known and well explained. I suspect that if you go over the explanations carefully you'll eventually see your mistake in interpretation of the evidence.
     
  8. Apr 3, 2015 #7

    PeterDonis

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    What he is saying is that it's not enough to just say "matter was moving apart faster in the past anyway". How much faster? How much faster in a model that does not include dark energy, as compared to a model that does? How much faster according to the actual data?

    Before trying to engage in your own speculations, you should get familiar with the massive amount of effort cosmologists have already put into investigating those questions. The current cosmological model that includes dark energy is the result of that massive effort; it's not something cosmologists just came up with because they couldn't think of anything else.
     
  9. Apr 4, 2015 #8
    My hypothesis is that astrophysicsts are wrong about expanding universe.
    The red shift of light from distant galaxies is not an indication that our universe is expanding.

    When photons from distant galaxies travel through space passing by many galaxies,
    on their way to Earth all those galaxies exert gravity pull to the photons.
    As a result the photons lost energy, but photons speed is light speed, it cannot loss energy my losing speed.
    The photons loss energy by red shift - (increase in wave lenght = reduce in frequency).
    And this effect accumulate over billion of years, the further the source, the higher the degree of accumulated effect - the bigger the redshift effect.
     
  10. Apr 4, 2015 #9

    Chronos

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    The expansion hypothesis is popular because it requires no new physics. Scientists are suckers for that. The gravitational redshift mechanism only works at the source. Intervening mass blueshifts photons as they approach, then redshifts them as they recede. Net effect is zero.
     
  11. Apr 4, 2015 #10

    wabbit

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    The test is not however whether the theory sounds good, but how well it accounts for observations. To see whether your theory is correct, you need to calculate the effect you mentioned and quantify it. As Chronos mentionned, the result can be quickly estimated to be zero, so your theory doesn't look promising unless you involve new physics - but then the burden is on you to justify this and make it work.
     
  12. Apr 4, 2015 #11

    Nugatory

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    The Physics Forum rules prohibit the posting of new personal theories that have not been published in an appropriate peer-reviewed journal, so threads about such theories are usually removed.

    This thread has been closed but not removed because the replies do such a good job of explaining why posting new and unsupported personal theories is a bad idea.
     
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