The edge and the center & the Big Bang vs Eternity

[SpeedFreek]

Yes completely still. But to <i> view </i> the rest of the universe, you also need to know where everything is.<br /><br />Where everything is <i> right now. </i><br /><br />Although very difficult, expanding space might be measurable and inertial movement might be predictable, but the speed of light will stop you from knowing what is out there and where it all is! <img src="/images/icons/wink.gif" /><br /><br />This is why I think a geometric centre is a purely arbitrary concept. It doesn't seem to relate in any way to a point of origin or anything significant. The point of origin expanded to become the whole universe.<br /><br />The point of origin for my house could be said to be the first brick laid, or the first concrete poured (awwww!). The geometric centre of my house is a point a few inches above the floor in the corner of my bedroom. <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>

 

[why06]

Still though we could learn the point of origin of matter as which may say a lot more for our universe than we currently know.<br /><br />Plus even if we have the the location of certain objects we can use mathematics and computers to predict their location at the present time removing the need for a reference point. <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>

 

[infidel]

So space is made of something? I imagine that the universe and everything in it is composed of some form of matter or energy, right? You said that it might be the expansion of space-time. This space-time thing, is that a real, existing substance? If I sound a bit igrorant on this whole suject, it is because I have heard so many different opinions from everyone who thinks they are an expert. All I really want to know is; is that thing we call space a real thing, if so, what makes it a real physical existance that is able to be bent.<br /><br /> Thanks for your patience, and help.

 

[why06]

<font color="yellow">Im sorry, but your getting way off here...<font color="white"> <img src="/images/icons/frown.gif" /><br /><br />Spacetime is not a "substance" <br />It is where you live. you exist in 4 demensions:<br />3. are made of space- (length, width, and height)<br />1. The forth is made of one demension of time ( because time moves in only one direction.<br /><br />See..., <img src="/images/icons/smile.gif" /></font></font> <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>

 

[SpeedFreek]

<font color="yellow"> Still though we could learn the point of origin of matter as which may say a lot more for our universe than we currently know. </font><br /><br />This is where I disagree. I don't think of the big-bang as an explosion <i> in </i> space, I think of it as an explosion <b> of </b> space. But explosion isn't the best way to describe it!<br /><br />Matter didn't originate from a point inside this universe. It seems to have started with great energy, <i> almost </i> uniformly distributed across the <b> whole </b> of the early universe.<br /><br />It is theorised that from a viewpoint anywhere in the universe you would seem to be just as far from the edge as anywhere else. And wherever you are, you are the centre of expansion.<br /><br />If we are looking for remnants of the big-bang, the origin, we look towards the edge of the universe, the place that may mark where the universe began, in every direction. <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>

 

[ianke]

You two do this conversation very well! <br /><br />I do have a question though. While we may run in to difficulty with pointing to it, wouldn't it make sense to think of the universe as having a center of mass (or Eintein Tensor if you prefer) no matter the shape? <br /><br />Wether one can point in a certain direction or not, couldn't one still think of the total universe as one thing? If so then the center or point of origin might just be possible to think of at least conceptually. <br /><br />While you pose the problems with finding the "center" quite well speedfreek, does it neccessarilly stand that why06's point is wrong? <br /><br />It seem to me to be a valid thought that there is an ultimate true center. It could come in handy indeed in further understanding of the observed processes if one could answer such a problem. Perhaps the endeavor would be in vane. Perhaps not, but the whole point of science it to find out what is there.<br /><br />I hope that I am not butting in. Please keep this thread going. This conversation is truly what I like to read about. <br /><br /> <div class="Discussion_UserSignature"> </div>

 

[Mee_n_Mac]

<font color="yellow"><i>"Wether one can point in a certain direction or not, couldn't one still think of the total universe as one thing? If so then the center or point of origin might just be possible to think of at least conceptually."</i></font><br /><br />I'm not sure of what use the info would be. Let me start by asking what you mean by "universe" ? If you mean our observable universe then I'd ask if you think there's more to the universe than we can observe at this time. If you answer yes again then the geometric center is right here and the mass center might tell you something about the mass distribution in that geometry which you'd have to measure to compute the mass center. It won't tell you much about the enire universe because who knows if our "local" mass distribution holds elsewhere. We've already mapped (I wish I had the link) the masses we can easily see and find there are clumps and filaments to the mass distribution (of visible matter). Then we have to wonder about dark matter. If there's more universe than we can see then we don't end up with a true center no matter what we do. So I'll opine the endevour is in vane. <div class="Discussion_UserSignature"> <p>-----------------------------------------------------</p><p><font color="#ff0000">Ask not what your Forum Software can do do on you,</font></p><p><font color="#ff0000">Ask it to, please for the love of all that's Holy, <strong>STOP</strong> !</font></p> </div>

 

[why06]

No "explosion is not the best way to describe it... <img src="/images/icons/wink.gif" /><br /><br />We know where space is.. its all around us... But what of matter. To say it didn't originate from a point is agood idea. But If we were to find this center we could find out...<br />The truth is that if the universe is infinite we have to ask why is matter here. What is matter. Did it come out of the Big Bang. If matter has a point of origin one has to wonder why is it there.<br /><br />Even if there is nothing to learn from this... there always the potential. The fact is that an experiment can be done.<br />As for energy turning into matter and being uniformly distributed I find this hard to believe.<br /><br />Why does matter have certain shapes in INFINITe sapce. It would seem that matter could be much more varied. <br />Why does light ave a certain speed.<br />Where did energy come from then if it created matter. And why would it turn into matter.<br />It seems like energy would want to stay at the speed of light. <br />Did the energy come from the big bang...<br />Well if it wasn't an explosion its just expansion I don't see why energy would be created.<br />Maybe their are thing besides demensions floating outside our unverse, but laws..<br />Laws of Gravity <br />Laws of Magnetism<br />Of Heat<br />O Energy<br /><br /><br />In other words I think the relative working of matter have to correlate to something.. even if there was energy it had to come from........ somewhere <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>

 

[why06]

<blockquote><font class="small">In reply to:</font><hr /><p>If there's more universe than we can see then we don't end up with a true center no matter what we do. So I'll opine the endevour is in vane.<p><hr /></p></p></blockquote><br /><br />Obviously space is expanding and matter is not..... That is why expansion occurs to cause red-shift (we think)<br /><br />If this is true it means there is more space than matter. Because if there was infinite matter we would still see it even if we have infinite space to put it in.<br />And there should not be more universe than we can see, because the universe is all we can see. Even blackness is something.<br /><br />Also this would mean th universe is expanding faster than light. Perhaps there is a reason for that. Perhaps matter is stretching space-time over long periods of time. <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>

 

[SpeedFreek]

Ianke<br />Don't worry about butting in as, speaking for myself, I have pretty much said all I think about the subject!<br /><br />It may be that Why06 is correct in saying that somewhere in this universe is the geometric centre. But as all this happened around 13.8 billion years ago, and the background radiation left behind is now pretty uniformly distributed around us, I doubt there would be anything of significance at this geometric centre. It would simply be an arbitrary point in space. And I doubt a geometric centre could be thought of as <i> the </i> point of origin.<br /><br />In the simplest terms, the point of origin was lost 13.8 billion years ago when it inflated into a universe! If spacetime didn't exist until after the big-bang, no point in spacetime can be considered the point of origin, or all points can be considered that origin point.<br /><br />I think of it like this - when the universe appeared, you might if you were <i> outside </i> the universe be able to point at it and say "There! Thats where the universe began!" But we are <i> inside </i> this universe and the point of origin became the whole thing.<br /><br />Why06<br /><font color="yellow"> if there was infinite matter we would still see it even if we have infinite space to put it in. </font><br /><br />Only if we have infinite <i> time </i> for the light from everything in the infinite universe to reach us. <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>

 

[why06]

<font color="red"> THIS IS A MOUTHFUL:<font color="yellow"> (you can try to skim it, but its less than it seems)<font color="white"><br /><br />How can you say our universe Expnade 13.8 billion years ago if we were already inside it.... I'm not much of an expert on the Big Bang (believe it or not), but I don't understand is how one can tell that the universe expanded if we were always inside it and here again i say expanded into what? nothingness. <br />- <i>If we are inside a singularity we would not be able to tell because sigularities have dimensions. And demensions only exist (as far as anyone nows) in this universe.</i><br /><br /><blockquote><font class="small">In reply to:</font><hr /><p><font color="yellow">when the universe appeared, you might if you were outside the universe be able to point at it and say "There! Thats where the universe began!" <font color="white"><p><hr /></p></font></font></p></blockquote><br />- <b>No you would not be able to point to it because there is no space there</b> ( I know you know this, but I am reinforcing my point)<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p><font color="yellow">Only if we have infinite time for the light from everything in the infinite universe to reach us. <font color="white"><p><hr /></p></font></font></p></blockquote><br />- If its been only 13.8 billion years.. how fast is the Universe expanding? What I'm saying I can put in an example. <i> Say you had an infinitely large bottle and had an infinite amount of matter to fill it with. The bottle would be full right </i>. Apply this to the universe.<br /><br />I'll try to do some research on the matter, but I am a little rusty... I think the big Bang is the fact that the Universe was a singularity with energy inside of it. as this Singularity Expanded the energy had more space and matter began to form. This is why there has to be a finite amout of matter, because are universe is expanding (we think) which means it is not neccesarily infinite yet. There fore an infinite mass can not fit into a momentarilly</font></font></font> <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>

 

[SpeedFreek]

<font color="yellow"> How can you say our universe Expnade 13.8 billion years ago if we were already inside it </font><br /><br />Well, <i> we </i> weren't inside the singularity, but what went on to be come this point in space was.<br /><br /><font color="yellow"> how one can tell that the universe expanded if we were always inside it and here again i say expanded into what? nothingness. </font><br /><br />The reason we think the universe is expanding is because at large scales, everything is moving away from everything else, as measured by their (cosmological) redshift. So it follows that earlier in th universes history, everything was closer together. Follow that back and everything all came from one small point. The universe didn't expand out past our current point in space, all points in the universe expanded from that singuarity. It didn't necessarily expand into <i> anything </i>. We are talking about the creation of all the dimensions of space here.<br /><br /><font color="yellow"> No you would not be able to point to it because there is no space there ( I know you know this, but I am reinforcing my point) </font><br /><br />Yes I understand that concept, but I think it reinforces <i> my </i> point! <img src="/images/icons/wink.gif" /> If all of space-time was created in a big-bang which inflated and expanded its dimensions, thinking of things like <i> outside </i> becomes futile. It is an unknown dimension. Therefore no point inside the universe is the point of origin because all spacetime was created <i> at </i> the origin. We are not talking about energy/matter and space spewing out from a point over a length of time and expanding, we are talking about all energy/matter and space appearing at once. And everywhere is expanding away from everywhere else.<br /><br />A 3 dimensional example (or 4 dimensional if you include time): When you inflate a car tyre, thinking from a point inside that tyre, where is the centre of expansion? Ok, we k <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>

 

[why06]

What I was really trying to say in the last pos were a couple things...<br />1. <blockquote><font class="small">In reply to:</font><hr /><p><font color="yellow"> I don't think I ever suggested there was infinite mass in the universe<font color="white"> <p><hr /></p></font></font></p></blockquote><br />-infinite volumes of matter imply infinite mass.<br /><br /><br />2. <blockquote><font class="small">In reply to:</font><hr /><p> <font color="yellow">But you said there is no space outside the universe. Therefore all of space is inside the universe. And if the early superheated quark-gluon plasma was (almost) evenly distributed throughout the whole of expanding space, then eventually stars coalesce throughout the universe (I say almost evenly distributed because if it was uniform, concentrations of mass would never have occured). This means there is matter everywhere in the universe, and there is no space outside it. If the universe has 4 or more dimensions as we seem to think, then its "shape" has to be thought of in those dimensions. If matter is pretty evenly distributed throughout all of spacetime, then you are looking for the "shape" of spacetime. <font color="white"><p><hr /></p></font></font></p></blockquote><br />- When i was talking about the shape I meant that finding the locations of galaxies and such could give us insight int WHICH parts of the universe is expanding faster than other. This would mean that there was not a uniform expansion. And the shape of our universe can still be viewed from the inside.<br /><br /><br />3. was there a universe before the Big Bang- <i> <font color="yellow">Even a singularity has to start somewhere</font></i><br /><br /><br /><br /> <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>

 

[SpeedFreek]

1. <font color="yellow"> infinite volumes of matter imply infinite mass. </font><br /><br />I don't think I suggested infinite volumes of matter either. It is you who introduced infinity into this discussion, I think! If zero volume = infinite density for a finite mass, does it follow that infinite volume = zero density for a finite mass? If that were the case, then we know the universe doesn't have zero density or infinte density... <br /><br />We have no evidence that the universe has infinite matter or energy in it. What do you think Einstein meant when he said the universe was "finite but unbounded"?<br /><br />To me this doesn't mean something as simple as finite mass unbounded. It doesn't mean the mass has an edge and then space goes on forever. To me, it means the finite mass in the universe has no bound, no edge. It "curves" back on itself dimensionally, somehow.<br /><br />2. Yes we should be able to see the shape from the inside, shouldn't we. So, what do we see? If we could detect differences in the expansion of different areas of space around it would tell us something about the universe, true. But all we see is everything expanding away at large scales, backwards in time. It makes it kind of hard to find a overall shape from our point of view.<br /><br />3. <font color="yellow"> Even a singularity has to start somewhere </font><br /><br />And the loop of discussion is complete. Can something come from nothing or not? <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>

 

[why06]

1. <font color="yellow">you were right!<img src="/images/icons/shocked.gif" /><font color="white"> it was Siaph that suggested an "infinite plane has no cente" and I took that to mean an infinit e amount of matter. It would be impossible to detect infinite "anything" so letts put that aside<br />2. <font color="yellow"> I agree.<font color="white"><br />3. <font color="yellow"> Can I say "anything" here <img src="/images/icons/cool.gif" /><br /><br />- Sorry echoub it seems this has really be come a two-person conversation that I think has just reached its conclusion <img src="/images/icons/laugh.gif" /><br /><br /><font color="white"><br />- We discused:<br />1. <font color="yellow">The Big Bang<font color="white"> -"can something come from nothing?"<br />2. <font color="yellow">Eternity<font color="white"> - "How can you detect the infinite?" "Or was the universe always here?"<br />3. <font color="yellow"> The Edge of the Universe <font color="white">- " geometric shape may imply rate of expansion?" "There is no edge because it can not exist?"<br />4. <font color="yellow"> The Center of the Universe<font color="white"> - "the center is back in time?""Would the geometric center have any signifigance in coparison to the actually center" "is there an actual center presently?"<br /><br />We discussed all these topics AND to be honest what's left. Unless anyone can post something else I believe this thread is done. <br /><br />Thankyou <img src="/images/icons/smile.gif" /></font></font></font></font></font></font></font></font></font></font></font></font></font></font> <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>