Can Expansion Theory Really Explain Observed Universe?

I was reviewing the current explanation for the assumed fact that galaxies rush away from each other at incredible speed. I came across the odd fact that if that was true, some galaxies would actually move at light speed.
So a friend of mine, an actually damn good physicist, too bad he doesn't write a book so people could easily learn physics from him, pointed me to the Expansion Theory.

According to the Expansion Theory, galaxies would in fact behave normally, but space itself, by expanding, would make those galaxies seem as they move away from each other at hight speed. Remember that astronomers and we physicist have never actually observed a galaxy move away, but we assumed that they do because Hubble saw that they were all (the galaxies, not the scientists) redshifted. Redshift means that the spectrum's dark bands are moved down toward the red bottom of the colour spectrum. As we all know that Fizeau-Doppler effect can cause a redshift (or blueshift, depending the direction), we think that galaxies are rushing away.
The Expansion Theory is supposed to explain why we see that redshift, and also why galaxies seems to move at such ludicrous speeds. It states that everything grows bigger, while every objects keeps their relative distance to each other. I saw the picture of a balloon, with tons of random polka dots on it (representing the galaxies): as we blow air in it the balloon expands, putting distances between polka dots. My friend prefers to think of it as a raisin bread rising in an oven. I must admit it does look a bit more pleasant (and delicious) to picture than a latex balloon.

But, using my balloon example, you immediately see something's deeply wrong with the Space Expansion Theory: everything expands... to scale.

I took the time to make a quick drawing of my thinking process. I rarely use equations, I have more of a graphical brain. I sincerely hope my choice of odd colours, for my drawing, will not induce headache, nausea of sudden urge to vomit.



One way we could solve this problem is by using an alternate view of space expansion. Instead of stretching itself, space could maybe "multiply" itself, that is, while "old" space is pushed aside, "new" space appear and, thus, create an expansion. This view was favoured by Leonnard Susskind, but now one would have to try an figure out this question: from where does all this extra space comes from? How the heck "new" space gets "pumped" into our universe? And why didn't we never saw "new" space being "pumped" in our galaxy or any galaxy for that matters? That's because this view is also faulty. Space stretching would give an universe in which we would see no change and no redshift, while space being pumped into existence would mean some sort of absurd "reservoir for space" would have to exist to slowly leak its space into our universe.

My point? Something's wrong with expansion theory! (no offence meant, CLPrime). The truth may be something else we didn't even thinked of yet.
We must keep our minds opened to the possibilty that physics is, currently, not exactly a perfect science.

I realize the pic is kinda big; here's a suggestion: click and drag it unto your desktop and open it using your computer. ATS is a bit small for viewing this pic.

I wonder too...

Is it because light moves matter through space which could be the expression of creation that is still ongoing??

My mind runs deep with questions.

reply to post by MamaJ


Well, here I try to prove that space "stretch style" expansion doesn't affect an electromagnetic frequency.

reply to post by swan001


Your issue with expansion would be legitimate if gravity didn't exist. But gravity does exist...and galaxies are gravitationally bound. Gravity acts opposite the expansion of space. Therefore, while space expands, gravitationally bound galaxies counteract it and stay the same size.
And, of course, there's the fact that universal expansion only becomes significant over millions of light-years, larger than most galaxies...which is why it's so easy for gravity to counteract it (gravity is significant over much more local distances).

Cosmologists and astrophysicists aren't idiots...if this were a problem, then metric expansion wouldn't be a successful theory.

reply to post by swan001


As for redshift...of course the expansion of space affects wavelength. In the time it takes an EM wave to travel from point A to point B, space has stretched by a given amount. This stretches the wavelength of the EM wave by a corresponding amount. It's not like the wavelength is something physical that can grow (in all 3 dimension) along with space...light is composed of point-like photons which generate an electromagnetic field. It's that (non-physical) field that has the wavelength...and that wavelength is stretched by the expansion of space.

Galaxies are not being held together by space, but by gravity. So when space expands, a galaxy is not affected. In your balloon analogy, it would be better to replace the polka dots with stickers (make from non stretchable material)

As for the red shift, it just means that light is affected by the expansion of space as it travels through it. I don't really see a reason why this is a problem. Light is not that much affected by gravity and uses "space" as its medium to travel in. So it seems to me it is along the line of expectation that light is affected when space expands.

reply to post by swan001

What CLPrime and PLB said.

Plus, I'd also add that perhaps a better analogy cosmologists like to use instead of dots on a balloon, is raisin bread baking. Like any analogy it has limitations, however note that the raisins don't get larger as the yeast in the bread causes the the space between the raisins to expand.

Raisin Bread analogy

Originally posted by Arbitrageur
reply to post by swan001

 

What CLPrime and PLB said.

Plus, I'd also add that perhaps a better analogy cosmologists like to use instead of dots on a balloon, is raisin bread baking. Like any analogy it has limitations, however note that the raisins don't get larger as the yeast in the bread causes the the space between the raisins to expand.

Raisin Bread analogy

whats the label, sun, for?

reply to post by CLPrime


"light is composed of point-like photons which generate an electromagnetic field. It's that (non-physical) field that has the wavelength...and that wavelength is stretched by the expansion of space. "

electromagnetic fields are non- physical?

Originally posted by ImaFungi
whats the label, sun, for?

That label is a little odd to me, but not inaccurate for the purpose of this illustration. Earth or Earth observer might be a better label, or Milky Way Galaxy.

It's an illustration to show that when we look in the sky, over 99% of all other galaxies seem to be moving away from us.

Originally posted by Arbitrageur

Originally posted by ImaFungi
whats the label, sun, for?

That label is a little odd to me, but not inaccurate for the purpose of this illustration. Earth or Earth observer might be a better label, or Milky Way Galaxy.

It's an illustration to show that when we look in the sky, over 99% of all other galaxies seem to be moving away from us.

how come all hubble images show galaxies always near each other,,, tons and tons in a single view,,, if galaxies have been expanding apart from one another for 13 billion years,,, should every single galaxy be a lot further from one another?

reply to post by ImaFungi


Right. EM fields are fields. Fields are (or, I should say, can be) metrics...they're about as far from physical as you can get.
And, speaking of metrics, the entire space-time manifold is a metric field (albeit of a different kind)...which is why, when it stretches, it's called "metric expansion."

Originally posted by CLPrime
reply to post by ImaFungi

 

Right. EM fields are fields. Fields are (or, I should say, can be) metrics...they're about as far from physical as you can get.
And, speaking of metrics, the entire space-time manifold is a metric field (albeit of a different kind)...which is why, when it stretches, it's called "metric expansion."

edit on 26-8-2012 by CLPrime because: (no reason given)

theyre about as far from physical as you can get,,, but they are still physical right? what are they if not physical?

reply to post by ImaFungi


No, they're not...they're physical (that is, having to do with physics) quantities, but they're not physical objects. They're tensor fields, tensors being mathematical in nature.
Even if you look at things like electric fields, which are mediated by virtual photons, they're still not physical (fermionic), but bosonic.

Originally posted by CLPrime
reply to post by ImaFungi

 

No, they're not...they're physical (that is, having to do with physics) quantities, but they're not physical objects. They're tensor fields, tensors being mathematical in nature.
Even if you look at things like electric fields, which are mediated by virtual photons, they're still not physical (fermionic), but bosonic.

Is there any way you can explain that a little simpler?

your saying electromagnetic fields dont physically exist,, because what produces their effects are virtual quantum particles that are capable of mathematically infinite behavior or something?

im trying to comprehend what you are saying is going on,,.., is this an effect that preceded macro matter? in that this non physicality was a fundamental style of the early quantum universe? or is the non physicality of electric fields an effect resulting from this quantum process being surrounded by larger physical clusters and laws governing them etc?

i know that probably didnt make much sense,,

Originally posted by ImaFungi
Is there any way you can explain that a little simpler?

Remember this equation?

E=mc²

Photons are on the left side. Physical objects like marbles are on the right side.

The c² means if you converted a marble to photons, you'd get an immensely large number of photons.

I'm not sure if that helps.

reply to post by ImaFungi


You were right up until the "mathematically infinite behavior." I'm not really sure what that means. But, regardless, you were right about the quantum particles...nothing in quantum mechanics physically exists. Wavefunctions aren't physical, and virtual photons (virtual wavefuncions) certainly aren't physical.

Fields are, at their most basic, an exchange of momentum. The word "field" doesn't really describe something that's actually there, it describes the magnitude of the change in momentum that one object produces in another object. When fields are mediated by specific particles, they're always bosons, which, again, are non-physical wavefunctions. None of this is affected by universal expansion.

reply to post by CLPrime


"You were right up until the "mathematically infinite behavior." I'm not really sure what that means. "

I just looked up the concept of bosonic and I guess foolishly guessed that many quantum particles occupying the same exact space was equivalent in some way to the concepts of infinity..

Originally posted by Arbitrageur

Originally posted by ImaFungi
Is there any way you can explain that a little simpler?

Remember this equation?

E=mc²

Photons are on the left side. Physical objects like marbles are on the right side.

The c² means if you converted a marble to photons, you'd get an immensely large number of photons.

I'm not sure if that helps.

edit on 26-8-2012 by Arbitrageur because: clarification

thanks for the reply,, and that does help,.,,.

But I still dont comprehend how photons can be physically non existent,,. I was under the impression that all phenomena are material/physical,.,..,.,

So to comprehend how massless, non physical quantom particles can construct a massive physical universe,,, one needs to assume things like the higgs field?