Dynamics of a collapsing universe?

[weeman]

According to our model of the big bang, the universe is constantly expanding, and always has been since the period of inflation. It tells us that the material universe didn't happen IN space, it tells us that it WAS space. We now theorize that the expansion of space is the metric expansion of the 'fabric' of the cosmos, rather than all galaxies sailing through an infinitely large and empty space. <br /><br />So, my question is this: If the universe may some day collapse, how would metric space begin to do so? If every point of space is expanding away from every other point, then it almost seems as if space is being created out of no where. So, how would the fabric of space collapse simply from the mass of all matter in the universe? The metric fabric of space would have to be pushed and compressed into nothingness (basically the exact opposite of the expansion that we are seeing today). <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>

 

[MeteorWayne]

At this point there is no reason to think it will collapse.<br /><br />The metric (whatever it is <img src="/images/icons/smile.gif" /> ) is expanding.<br /><br />However were a collapse to occur, you are correct. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[weeman]

I guess that's the idea of the 'Big Crunch' <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>

 

[vogon13]

Maybe universe is shaped like a torus (in n dimensional space) and without changing direction, everything winds up back in starting singularity.<br /><br />{yeah, wrap your brain lobes around that one !}<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[a_lost_packet_]

If mass effects the fabric of space-time, which we believe it does, then enough mass will cause an eventual collapse given that gravity works as advertised.<br /><br />Right now, a Cyclic theory doesn't have much evidence supporting it to be able to withstand close scrutiny. That could change as knowledge increases... or not. <div class="Discussion_UserSignature"> <font size="1">I put on my robe and wizard hat...</font> </div>

 

[alokmohan]

Most intricate problem under earth.

 

[mindmute]

Black holes warp space so powerfully, that light cannot escape the "fabric's vortex". but how much fabric is being gobbled up by these cosmic hoovers? or is the fabric just stretching, and if so, how thin can it get?<br />While there is currently no proof of a cyclotic universe, everything else within it seems to have a measure of harmony.

 

[alokmohan]

Cyclotic universe?I dont know it help.

 

[mindmute]

cyclitic sounds nasty. <img src="/images/icons/smile.gif" /><br />

 

[nexium]

Details change a bit each year. Perhaps 40 years ago we conclude the Universe did not have enough matter to collapse and would expand forever. About ten years ago, we decided the rate of expansion was increasing, which made future collapse extreemly unlikely. Also about ten years ago we decided that the Universe might have ten times, or even 100 times as much dark matter as it has visable matter. This made a far in the future collapse likely, if the there is really lots of dark matter. More recently dark energy = reverse gravity was theorized (perhaps a means to account for the accellerating expansion, we have observed) So for the present the Universe will expand faster for a many billion more years, then the accelleration will fade away for many more years, then the expansion will slow. Perhaps a trillion years from now, the universe will be so big that gravity will be too puny to pull it back together. After about a billion times a billion years, most of the stars outside our galaxtic group of about 20 mostly small galaxies, will be so far away, that we will need much more powerful telescopes to see them.<br />Our own galaxy will have made stars out of nearly all the dust available, and the brighter stars (including our Sun) will have become compact stars long ago, and most of the class m stars will at the end of main sequences or long grown dark. Any sentient beings will have little to see in the sky, even with a telescope.<br />A new theory is probable in a few more years. Please correct, refute and/or embellish. Neil

 

[gammarayburst]

Neil, the theory would need to be rethought if matter is found to be created 90° to a stars magnetic equator, or magnetic reconnection, like I once theorized, see : http://www.msnbc.msn.com/id/23031710