[Cspace]

As many probably know (at least the basics of this theory), Einstein proposed the idea that a force known as antigravity prevents the galaxies from coming together and forming a single system (since gravity would attract them and cause the universe to collapse). This is an explanation for the universe's expansion. Since gravity pulls matter together, he theorized that a force must be pushing the galaxies apart from one another to overcome this (since every galaxy has been found to be moving away from us by measuring their redshifts).

I believe that this is the most plausible theory at the moment (antigravity), but in class I randomly thought of something else: What if there's something "outside" the known universe pulling everything toward it?

While I severely doubt that this is the case (since the shape of the universe isn't a sphere but is supposedly an irregular shape), some force between parallel universes (the soap bubble model) could contain a large amount of gravity. This could be considered like a shell pulling everything toward it. Galaxies closer to the "shell" would move faster than those farther away (gravitational pull would be greater), and they would be moving in different directions to one another connected at a common center point (if a line is drawn connecting the center to the galaxies).

/|
\|

The little model thingie above is exaggerated, but it shows how galaxies would appear to be moving apart. The angled lines are the paths of galaxies, and the | (or) symbols represent the distance. It would increase as the galaxies moved farther out, which would be the cause of the galaxies to appear to move away from us.

The measured acceleration could be attributed to the galaxies being pulled by a larger gravitational force the closer they get to the "shell". We would be moving at an increasing velocity, increasing the gap between us and those galaxies closer to the center at an exponential rate. This would make them seem to be accelerating away from us. The red end of the spectrum measured in their red shift shows that the galaxies are moving away from us, as would appear in this case.

+)__)____)______)________)#

The plus symbol is galaxy 'a', we are the number sign, and the parentheses are the emitted electromagnetic waves. While we are accelerating away, the frequency of the electromagnetic waves emitted from galaxy 'a' seem to stretch. This causes the galaxy to appear in the redder spectrum (like the Doppler Effect: The pitch decreases as a car speeds past you as the wavelength is stretched relative to your position).

Another measured element is that galaxies appear to be moving faster the farther from us they are. This would make the waves appear even farther into the red spectrum.

+)__)____)______)________)____________)______________)#

As shown above, the farther galaxy would appear redder than galaxy 'a'. This would work in the opposite direction as well:

#(__(____(______(________(@

Pretend the at (@) symbol is galaxy 'b'. While it is accelerating away from us at a faster rate (it is closer to the "shell"), its waves would appear to be redder as well. As the waves move past us, the wavelength should increase.

#(______(________(__________(____________(@

As I said, I don't believe that this is true (there are factors that go against this, like the acceleration of objects not directly in front or behind us), but I'm just trying to keep my mind open and think of other ideas since as it is we really know very little about the universe's structure. Thought that I'd share my idea though (I don't believe that I've seen another theory like this), feel free to post comments and your own ideas as well.

[Kowboy]

I suppose there could be something outside pulling us to it. Mabye like a "huge blackhole" type of system. (Vaccum.) If space is curved or some other type of elliptical shape then it could be possible. Well call it Cspaces Theory of "Galaxy Shifting." LOL.

[yeah man]

Didn't Einstein propose that there are some dips in space or something. and that this idea could be used a propultion to accelerate ships?

[CongressJon]

My, my, my... this man knows quite a bit

With this theory of "antigrvity", I once heard a bit about the "dark matter" in the universe. I think they both have something to do with each other, considering the parts they play in the universe(s).

[Cspace]

Antigravity and Dark Matter are similar in that they have never been measured and make up for the missing forces required for our current model of the universe to work. Many believe in Dark Matter, though I would have to say that I don't believe it exists (just me, both sides have major arguments).

Dark Matter is basically a form of matter which would make up for the "missing" matter required to stop the universe's expansion. Here's a piece of an essay I wrote about the Big Bang last year (can be seen in its entirety here):

"It has also been theorized that the amount of matter in the universe would affect the speed at which galaxies and other objects form. The less matter there is, the less gravitational force it can exert on other matter. Only one or two percent of the universe consists of matter, and this would obviously further slow down the creation of large galaxies and objects. It has been estimated that about ten atoms per cubic meter would be required for gravity to form large galaxies, while the actual density of the universe is around one atom for every ten cubic meters of space (about one hundred times more matter would be required). The density of the universe as a ratio to the density needed to stop the expansion of the universe is called "omega" (Lerner, 34). Theoretically, if there were enough matter to stop the expansion of the universe, omega would equal at least one. It seems that omega is really equal to about .01 to .02. This is much smaller than what is required for the fluctuations to form galaxies in the given amount of time. To make up for the difference, a mysterious, unobservable form of matter had been assumed, called dark matter. Lerner describes dark matter as "the little man who wasn't there" (Lerner, 34). Dark matter has never been observed, measured, or proven to exist. No real clues exist proving that it is there, but it would be required for the Big Bang theory to work. Chances are that dark matter does not even exist. If dark matter were considered "ordinary matter," an excess of helium and lithium would exist and the "nuclear soup" would not be the proper density (it is predicted that there was an abundance of helium and rare light isotopes like deuterium [heavy hydrogen] and lithium). So dark matter cannot be ordinary matter. Since the theory would not make much sense if dark matter were ordinary matter, some scientists believe that it could consist of high energy particles such as heavy neutrinos, axions, and WIMPs (Weakly Interacting Massive Particle). These particles could provide enough mass required for an omega value of one, and are almost impossible to observe (Lerner, 34). What does not make sense is that there was no evidence of their existence and a very large amount of dark matter would be needed.

For quite a while, astronomers have been searching for clues to prove the existence of dark matter. By measuring the speeds of galaxies and their rotations, it seems that there is more mass in galaxies than in stars alone (five to ten times more in clusters). Many think that the extra mass could be dark matter, though there was only enough to bring the value of omega up to .1 (one tenth of the required value). There is also room for error, in that the value could very well be less. This could occur if the redshifts measured to find the mass of galaxies (from the speed of their rotations) were thrown off by interlopers. An interloper is when "a galaxy nearer to us than the cluster to which it appeared to belong could be mistaken for one in the cluster that is moving toward us, while one farther away could be misidentified as a cluster galaxy moving away" (Lerner, 36). If interlopers were included in their calculations, the calculated mass of the clusters would be less.

Another potential error is if escaping galaxies were included as members of the cluster. These galaxies would not be bound by gravity to the cluster, and this would further cause an overestimation of the masses of the clusters. These two errors would account for all the missing matter in galaxies and clusters, therefore leaving no space for dark matter. The masses of nearby galaxies were later measured by Mauri Valtonen and Gene Byrd (who found the potential errors of the original mass calculations), and it was found that the galaxies contained no invisible matter. This means that the omega value would still be around .02, showing that dark matter probably would not account for the required mass for the Big Bang to work."

At the same time there are arguments in the other direction and I don't want to influence everyone to think that what I said is conclusive. The theory is much deeper than this, though I related it to the Big Bang in the section refuting it (I don't believe in the Big Bang, at least in the current state of the theory).

Note: If that was a little confusing, I made references to topics I addressed earlier in the essay, so feel free to check out the rest if you'd like.

[Cspace]

Double post (update to my "theory") - I can survive being defenestrated a couple more times...

Possibility in favor of my idea (still don't believe it though ): Since the behavior of galaxies would appear different if they are of similar distance to the cosmic "shell" (not in front or behind), what if the arm of the Milky Way is blocking our view of these galaxies? The arm is definitely blocking our view of very large pieces of the universe, as can be seen in this image (2D map of the known universe):



The blackness to the left and right is caused by a variety of factors (blocking our view). What if we happened to be aligned parallel to the source of the gravity? Then the accelerating galaxies that we see would only be in front and behind us. Just thought that I'd throw that unlikely topic in as well

[CongressJon]

*Defenstrates Cspace three times*

It's a very good theory, but it's too bad that we can't prove it... yet.

[Kowboy]

Cspace, I think you should change carreer paths and be an astronomer or something.

[CongressJon]

Astropycist more like

[Stargate3216]

But what would cause anti-gravity?

[Nuu™™]

This topic is really old but anyway. I am not a big fan of dark energy, or as you call it, antigravity, I think it is a bit far-fetched. It is only based on the fact that astronomers saw distant supernovae on a more red shift than before. I certainly like your idea better Cspace. I think that maybe a gravitational abnormality is more likely that would bend the light, maybe fooling the thing that does the shifty spectrum thing (forgot what it is called, you know, that works out red shifts and blue shifts), but that probably doesn't work.

[Spikeout]

I thought Inertia was the force keeping gravity at bay?