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/sci/ - Science & Math

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5731859 No.5731859 [Reply] [Original]

Galaxies appear redshifted. The farther away they are, the more redshifted they are. The accepted explanation for this is that these galaxies are moving away from us, probably because of some expansion of the universe. The farther away they are, they faster they move away. Is this basically correct? Can anyone point me in the direction of evidence that the apparent size of distant galaxies appears to shrink, and that the farther out they are, the faster they appear to be shrinking?

>> No.5731861

>>5731859
>Can anyone point me in the direction of evidence that the apparent size of distant galaxies appears to shrink, and that the farther out they are, the faster they appear to be shrinking?
Length contraction, relativity?

>> No.5731860

>galaxies seem to shrink
Nigga what?

>> No.5731867

>Length contraction, relativity?

I asked for evidence, not theory.

>Nigga what?

If a galaxy is moving away it should look smaller.

>> No.5731882

>>5731867
I... What? You're asking how much smaller they look? What is this for?

>> No.5731883

>>5731859
It's called the "plum pudding model" I'm not kidding.

The metaphor is that galaxies and matter are like plums in the pudding. And also it's like when you bake batter, as it heats everything expands and the stuff farthest out expands the fastest/farthest.

>> No.5731891

what the hell is this thread? So many confused people ITT......

OP, what you're thinking of is this:
http://en.wikipedia.org/wiki/Hubble%27s_law

enjoy.

>> No.5731898

>>5731883
>sounds like
http://wiki.answers.com/Q/There_is_a_model_of_an_atom_with_grapes_and_gelatin_in_a_bowl_what_would_the_gelatin_and_the_bowl_be
Couldnt even find the actual wiki page, that how fucking obscure that model is these days

>> No.5731906

>>5731859
I think it's not the farther away they are. You're talking about the doppler effect of stars, it's the more redshifted they are, the faster they're moving.

>> No.5731911

>>5731898
>obscure
It's like one of the earliest models you learn in chem.
http://en.wikipedia.org/wiki/Plum-pudding_model

>> No.5731914

>>5731911
Yeah that's needless BS relation for learning it, USfag?

>> No.5731916

>>5731914
Well, lol, he discovered the electron, so, guess it figures lol

ffs though humanity....

>> No.5731920
File: 63 KB, 397x394, whatthefuckamireading.jpg [View same] [iqdb] [saucenao] [google]
5731920

>>5731914

>> No.5731931

I think OP is talking about them literally appearing to shrink? Like, galaxy X looks smaller today than it does yesterday, because it's farther away than it was yesterday.

But of course time scales are way, way too short to see something like that.

>> No.5731934
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5731934

>>5731920
Well shit if they progress into DNA the electron Orbitals are SOOOOO relevant! And making more complex chemicals you might need them but idk bout that

>> No.5731944

>>5731934
Can't you shit up /x/ or something when you're high?

>> No.5731943
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5731943

>>5731931
Yeah but I think its more to the extent of they appear to be going faster than they are with the way we observe them

I think it has to do with the constant c expansion OP, that OR, BH's and gravity waves w/ doppler OR! They most likely explanation, we're all on drugs.

>> No.5731946
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5731946

>>5731944
NEVAAAAAA

srsly >>5731622 and you guys still cant think
Seriously, youve had 2nd law of thermodynamics shoved so far up your ass your using it to chew

>> No.5731968

A found a good review of what you're after.
http://arxiv.org/abs/1002.0525
It's a long paper, if you're looking for others or additional distance measures let me know.


Are you debating plasma cosmology people or electric universe nuts>

>> No.5731971
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5731971

>>5731859
God there are so many people in this thread who have no idea what they are talking about, even though this is all 101 stuff. Please don't pay too much attention to them.

What you are asking is whether galaxies at a higher redshift have a smaller angular size. To think that they would is a logical assumption--objects have a larger angular size the closer you get to them. However, this is not what we observe when we look at galaxies. Pic related is a plot of the expected relationship between angular size and redshift for objects in several universes with different expansion histories (that is, the different lines correspond to what the curve would look like based on how rapidly the universe was expanding at different times in the past). As you can see, beyond a certain redshift, the expected size of galaxies in the expansion model of the universe no longer decreases, and actually increases after reaching a minimum value. The reason for this prediction is that, when the light from those very ancient (hence, highly redshifted) galaxies was emitted, the universe itself was much smaller and those galaxies would've taken up a larger proportion of space in their observable universe.

This is in fact what we observe when we look at the sky. The ultimate example is the cosmic microwave background radiation itself. The CMB is the light emitted by the soupy cloud of ions that formed a few thousand years after the big bang, when the universe was still very tiny. No matter which direction we look, we see an almost uniform "glow" of extremely redshifted light. I.e., the angular size of this light is "the whole sky." Even though the ball of glowing ions would be a small object in today's universe, since it existed such a long time ago, it filled the entire universe it existed in. Hence, it's light continues to reach us from every direction.

In short, looking back in time "stretches" things because space was smaller back then. This helps confirm the big bang theory.

>> No.5731978
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5731978

>>5731946
Seriously though our education system distributes 'circuitry' into it soooo heavily, its incredible really
>mfw

>> No.5732044

>>5731859
What you wrote makes some sense but as the speed of light is a constant to all observers then the light from things that were closer should have reached us sooner. It seem to me that the more intense red shifts may be more the result of relativistic effects. I will need to study this further. Thank you, you gave me something to think about.