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Author Topic: Does Dark Matter lead us to overestimate of the size of the universe?  (Read 1511 times)

Offline jrussell

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A) light is a cosmic speed limit, but we know light can go slower than that speed.

B) We ponder the presence of Dark Matter

C) If there is, as postured, another form of matter in the universe, and light can be slowed down, is it possible that the universe is, in fact, smaller than estimated if it has been measured using light at its speed limit if that light is having to go through extra matter?



Mod edit - I've formatted the subject as a question, feel free to change it to something more accurate.  Please make sure all your subjects are in the form of a question - it makes the forum tidier and easier to navigate.  Thanks.
« Last Edit: 30/04/2010 12:06:12 by BenV »


 

Offline Stan U

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I was having a similar thought this morning....I saw recently that quasars don't have a time of arrival of light that correlates to their apparent distance.  What if they've blasted the interstellar medium that we can't "see" as a result of their going nova?  Further, what if the apparent red-shift that we've used to gauge the expansion of the universe is actually being shifted by this interstellar medium referred to right now as dark matter?

Aerodynamicists have used Schelerin as a technique to visualize shockwaves in atmosphere for a long time.  The compressible flow in a shockwave alters light such that you get a shadow on a projected surface.  I understand that this is an atmospheric effect, but I wonder if it isn't extensible in this regard.

What if the resultant of dark matter is a fundamental red shift in the local area?  Have people been looking at darker areas of the universe and getting different results on red shift?  Is the cosmic microwave background a similar correlator?
 

Offline PhysBang

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I was having a similar thought this morning....I saw recently that quasars don't have a time of arrival of light that correlates to their apparent distance.
This is not the case. Quasars, on average, don't look like they should if much of their difference in fluctuations is due to their distance from us. It could be that much of the fluctuations that we see in quasars is due to things in between us and the quasars, or there could be some interesting systematic error in the particular study done.

What we do know for sure is that every time we have been able to measure the distance to a quasar through a number of different techniques and check their time dilation, these things agree and they place the quasars at the same distance.

There could be some sort of interstellar medium interfering with astronomy, but it would have to not only be very weird, it would have to coincidentally be interfering in different ways with different type of observations in exactly the right way to fool all of them to conspire in distance measurements. This in itself seems unlikely.
 

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