expanding universe: Red Shift

Edwin Hubble's observation of a red shift in starlight led to the conclusion that our universe is expanding...

this is because starlight that is emitted on the blue end of the spectrum shifts towards the red end.

objects further out in space have a greater red shift than those closer to us, so....
does the blue end of the spectrum signify a slower rate of travel than that of the red end? or is it that gas in space absorbs/distorts the blue end easier than the red? The more gas inbetween a light source and its observer, the greater the red shift.

they have produced, in laboratory tests that passed light thru gas, the same red shift effect (on scale) as those observed in space... this having nothing to do with the rate of light travel (well, light does slow down when it passes thru gasses/prisms/etc. but "speeds" back up to the same rate of travel upon exiting the material)

there is more matter/gas/what have you, between us and objects further away. is it not safe to conclude that the increase in red shift observed in objects farther away is due to light passing thru more gas, rather than a greater rate of expansion intrinsic to bodies further out in space?

with the naked eye i can see starlight turn from white to blue to red and back again. (twinkle twinkle little star) it would seem that i observe light that is passing thru, at times, material in space that creates this "twinkle effect".

so what's the truth? or what are the opposing points of view?

Very good and interesting question. I just watched some lectures from Berkeley explaining the essence of the universe. The measures that astronmers have used to figure out the redshift of the universe are on a quite massive scale. It's not like they've just measured three stars to figure it out. Only 5% of the universe is made out of visible matter, with something like .2% being solid and not a nebulous gas. The rest of the universe is nothing..just voids between galaxies evolved and unevolved. Because of this, I don't think that passign through a medium is affecting their studies or observations that much. That's the closest I can come to touching on it and offering an explanation.

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i don't know how to explain it, but that's what they've scientifically proven. Find the TTC What's New in Astornomy lectures from Berkely and watch all twelve.

In order for the universe to continue expanding, som e73% of the universe needs to be made of dark energy..and a furter 22% dark matter. Thus leaving us with 5..in a VERY basic interpretation. Physicists, help me out here .

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there is only so much matter, albeit always changing forms. There are also antiquarks, quarks, neutrons, positrons, etc. that continually pop in and out of existence, annihilating each other.

It's truly mindblowing.

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90-95% of all matter is contained outside of galaxies, in the voids between. Is that what you're wanting to know?