BF2S Forums Dark Matter causeing our universe to expand?

Well, one thing is for sure...when this world has come to armageddon and jesus returns to wrap it up, we'll all know EVERYTHING we always wanted to know about this solar system and other universes!   We'll even know who killed JFK!

Erkut.hv wrote:

cpt.fass1 wrote:

So basically it's somewhat proof that the explosion of a supernovia is what causes space to expained and not collapse on itself due to gravity..
I'm not really too much into the whole "Space" and where we come from stuff so I was hopeing for someone who was to expaine theory's a bit better.

In theory, my theory anyhow, the universe expanding would eventually lose the ability to sustain it's momentum. It would thin itself out so much from expanding, that it will eventualy start being pulled back into itself. When that happens, all the mass gets pulled back into the center, until it can't be contained any further. Then....

Big bang all over again. Then everything gets created, again.

The question still remains:

What created the stuff in the first place? And if my theory holds, how many times has it happened? And if energy can neither be created nor destroyed, simply transferred, what the hell was I before I entered this shell? Or the last time I was in the universe before it imploded.

My head hurts, thanks guys.

Sounds like a neutron star on a universal scale. That would be cool. Some of the stuff that goes on out in the universe is so wild I can't fathom why God would invent it..../sarcasm

PspRpg-7 wrote:

I think that it's not going to mean shit to us, maybe to the people a million years from now...

In a million years there will be no people.

Interesting. The same stuff that made the last two levels of Half-Life 2 easier than the fisrt three is causing the universe to go so far apart it may "burn out".

IG-Calibre wrote:

hmm.. generally it's the rebels who fight for the republic, maybe you meant the empire per chance?

Ah, no.  The rebels fought to create a new republic.

God I feel like such a nerd, arguing about Star Wars on a video game forum.....................

i love this kind of science
"we can't see it, measure it, or test for it in any way shape or form what so ever, but it must exist because you can't think up anything better"
like the theory of the atom really...
as for god, i don't really care about sed celestial being, after all i don't care whether he/she/it likes me or not so why should he/she/it?

I have not yet reached general relativity or astrophysics in college (so take this all with a grain of salt, cause i have little to no math to back it up), but from what I understand about the whole thing is this.

This all arises from problems with Hubble's Law and redshifting.  Redshifting is the recessional form of the doppler effect, which states that the wavelength varies with the relative velocity of the transmitter and the receiver with respect to one another.  If light travels towards us while ourselves and the source are approaching one another, the wavelengths become shorter, resulting in a shift toward the blue end of the spectrum (blue shifting).  Redshifting occurs when source and observer are moving apart (wavelength increases).  Hubble's law is v=H_0*D, where v is the recessional velocity between source and observer, H is the distance between them, and H_0 is Hubble's constant at present.  We say at present, because as it turns out Hubble's constant varies with time.  This rather straightforward equation allows us to determine the rate at which stuff is moving away from us for a given distance, within some error garnered by the inherent imprecision of the Hubble constant.  In addition, since Hubble's constant varies with time, knowledge of its value and some good ol' differential equations can yield the age of the universe. 

So this is all fine and dandy right?  But what I haven't told you yet is that evidence from the observation of supernovae in other galaxies suggests that the rate of expansion of the universe is accelerating.  Basic Newtonian physics tells us that where there is an acceleration, there is an accompanying force, so there must be some sort of inherent repulsive force acting on the entire universe in a relatively isotropic (uniform) manner.  This means that there is some sort of matter or energy which must outnumber normal matter and energy and be repulsive, or our theories could just be flat wrong.  But assuming the theories are close to correct, we are left with one stunning conclusion: There should be some sort of dark matter and dark energy present in the universe which is repulsive rather than attractive. 

Conclusion: Nothing, not yet, give it a few years of research.  No real consensus has been reached, so its pretty much anyone's guess at this point.  More data needs to be collected, and more thought needs to put into it. 

Corollary to the Conclusion: For crying out loud, SUPPORT A SPACE PROGRAM.  Oh, and SUPPORT THEORETICAL PHYSICS RESEARCH (I want a job when i graduate).

MaximaRX wrote:

Let us consider this: The universe as we are currently thinking about it.....(at least some of the posts here).... May not have a "limit". Suppose that the "universe" itself is only the amount of matter and energy we can see, measure, and theorize. Hence, the universe is all the galaxies, stars, etc. After all, most of the space out there is a vacuum. So let's assume that all of this stuff is merely expanding/moving away from the center of the vacuum/void we call space.

Make any sense?

What you are considering as a vacuum is actually where dark matter exists. Dark matter accounts for more than 10x the mass of baryonic matter in the universe. What is considered to be nothing in fact accounts for more of the universe than all the 'real' matter in it.

Very few modern theories leave any room for the universe to be existing as merely the debris from the Big Bang as you suggest (which is the most simplistic view of the universe and not generally considered to be in the least bit likely). It is not simply an area filled with matter and energy but it is considered to be the space and time that the matter occupies.

IG-Calibre wrote:

I'd just like to know what exactly is it expanding into, no matter how much spliff I toke I just canny get me head around it!

Nothing, in theory. It's just getting bigger, as spacetime expands then there is more space for matter to inhabbit which leads to many things getting further apart.

Last edited by Bertster7 (2006-11-18 09:17:20)

Just goes to prove that the universe cannot be infinite, as the term "expanding" refers to getting bigger.  If it is already infinite, it can't get bigger.

Hundreds of years of scientific research down the shitter.  The universe is not infinite, just pretty fucking big.

Last edited by Penetrator_01 (2006-11-18 09:43:51)

Micheal Moore is proff of this theroy. 

He is full of Dark energy and look at how much he is expanding with time.  He should get more dark matter in his diet.

Locoloki wrote:

probably just pulling from the edges and pusing itself back thru the middle so, (dark matter made = dark matter lost), eventually we will be sucked right off the edge and life will come to an end, that's just my theory though.

I think you've mis-interpreted what dark matter and dark energy are.

Dark matter is non-baryonic, non-observable matter - that we know very little about. Dark energy is the modern equivalent of Einsteins cosmological constant, the force that stops gravity from causing the universe to collapse in on itself.

(all very much oversimplified)

Bertster7 wrote:

jonsimon wrote:

If the universe is expanding, shouldn't things be relatively uneffected? I mean, distances between celestial bodies should increase marginally, but for the most part, things in our neck of the woods shouldn't change much, the distance between our sun and our planet shouldn't be greatly effected (relative to the overall expansion of the universe) and celestial bodies should be the slightest bit denser as a result of the miniscule change in the gravitational pull of other bodies, but otherwise, I don't see any immense implications.

You're right. But I'd think it would be the other way round, density of celestial bodies getting less as there is more space and the same amount of celestial bodies.

But the increased space between celestial bodies would decrease the gravitational pull of all other celestial bodies on the matter of, for example, the earth. Meanwhile, the earth's gravitational hold on it's own matter would remain constant.

While matter does have a tendency to diffuse, the gravitational pull of earth is currently enough to suppress that tendency, so unless more empty space somehow increases matter's tendency to diffuse (which I don't think it does?) earth would become marginally denser.