Space/Time

[doorma]

How can time exist in an infinite universe exept as finite artifice? The time it would take to travel to the end of the infinite universe and back is exactly the same amount of time it takes only to get half-way.

 

[scull]

"...travel to the end of the infinite universe..."<br /><br /><br />Infinity has no end.<br /><br /><br />--

 

[doorma]

If it has no end, it also, by definition, would have no begining. Therefore any "trip" to the end of the universe would have the same spatial relationship as a trip from any point to any other point. All "trips" would take the same amount of time--zero.

 

[scull]

So far there is no suggestion that the universe folds back on itself (ie. no bits of the universe look like they are repeated from other bits), and the current indications that the universe will expand forever, favor models which are infinite and eternal.<br /><br />So-called "singularities" which probably only exist within black holes, represent an end to space-time, so although the universe itself may be eternal, there could be a real end, in some sense, for anyone unfortunate enough to meet one.<br /><br />The discovery of new physical processes, of course, could change everything, but speculation to-date is generally along the lines of "infinite and eternal".<br /><br />--<br />

 

[unlearningthemistakes]

time is just an intangible measurement. time measurement was invented to accurately predict occurrence of the "next-thing-to-happen". if this space expands forever, so does time. space-time. <div class="Discussion_UserSignature"> <p>pain is inevitable</p><p>suffering is optional </p> </div>

 

[doorma]

What, I wonder, does space expand in to?

 

[unlearningthemistakes]

<font color="yellow">What, I wonder, does space expand in to? </font><br /><br />that's the common question. it is not this universe that expands inside an empty space. It is space itself that expands. Did I got your question right? <div class="Discussion_UserSignature"> <p>pain is inevitable</p><p>suffering is optional </p> </div>

 

[doorma]

But, still--what holds space? It must, ultimately, be emptiness.

 

[unlearningthemistakes]

that, we do not know. <div class="Discussion_UserSignature"> <p>pain is inevitable</p><p>suffering is optional </p> </div>

 

[doorma]

Well, I'm gonna find out. I'll report back.

 

[scull]

"What, I wonder, does space expand in to?"<br /><br /><br />Ahhh, this is a difficult question, doorma, because there's so much we don't know about the nature of the Universe.<br /><br />The Universe has no "outside"; so there is nothing outside for it to expand into. Think of it as a balloon. A balloon can expand in diameter without having an edge that pushes into something.<br /><br />The Universe does not need to expand into anything since it has no edge.<br /><br /><br />This kind of stuff hurts my brain.....<br /><br />--

 

[kmarinas86]

The balloon doesn't expand by itself. Air, or some other gas has to rush into it. Air is independent of the balloon fabric. Yet is it as much as part of the universe as the balloon is.<br /><br />We can't see the iron core in the center of the Earth, but we can infer that it exists. The universe should be the same way.

 

[scull]

I agree the balloon is not a perfect analogy. What I was trying to answer is the question "what is space expanding into."<br /><br />So to get back to the original question, the balloon is a two-dimensional surface embedded in three dimensional space and that it is expanding into that space. That's true in our experience, but mathematically, the balloon does not need to be embedded into anything, just like our three dimensional space does not need to be embedded in a higher dimensional space to exist. So, as a mathematical space, the universe does not need to expand into anything since it has no edge.<br /><br />--

 

[doorma]

Assuming that both the balloon and the space into which it is imbedded cannot occupy the same space at once, it would seem that the balloon must displace the area of pre-existing space, which must then displace other space, etc. If the universe--or anything else, for that matter--is expanding, it must expand (displace) something else, unless nothing else was there to begin with. This brings us back to emptiness, which, ultimately must even be empty of itself. Therefore, the time it takes for one piece of matter to change locations within space must be zero, if space rests in emptiness. The sun really doesn't set in my dream.

 

[harmonicaman]

<i>"If the universe--or anything else, for that matter--is expanding, it must expand (displace) something else, unless nothing else was there to begin with."</i><br /><br />Yes! The universe is not expanding into something - it is the creation of time and space itself!<br /><br />Look at it this way... <br /><br />The universe is a <i>singularity;</i> an infinitesimally small point. When the BB event occurred, space and time were created <i>within</i> this infinitesimal small point. (Note that the "Outside" of our singularity universe can not expand because there is no "Outside" for it to expand into; the expansion of time and space is occurring totally within the confines of the singularity!) <br /><br />Every point in a singularity perceives itself as being located at the very center of the singularity; and that is why every point in the universe sees itself as being located at the very center of the universe - the rules of the singularity hold true even though space and time are being created within our universe.

 

[doorma]

Yeah, the singularity. That, of course, is where I will end my term paper. If space is fear, the singularity is insanity (Where did the singularity come from? Nowhere--there is only singularity. But what held singularity before the BB? Nothing--only emptiness existed before the somethingness of the BB. But if there was a first moment simultaneous with the BB, doesn't that imply a zero moment? And if there is a Zero Moment, there must be something before the Zero Moment--in fact an infinite amount of moments awaiting the first. Existence implies (creates, out of necessity?) non-existence; you can’t have one without the other, regardless of the flavor of the singularity.) I have always depended on the kindness of strangers.

 

[siarad]

You don't seem to understand the meaning of nothing, it's not emptiness, which requires a holder & time to see it. Nothing is without form or mass or energy or time.<br />Expansion <i>into</i> nothing makes no sense either. it has no existence.

 

[doorma]

Thank you for pointing out my lack of understanding. That's very helpful--if what I needed to understand was that you are one who understands. How nice for you. However, it seems to my limited understanding that if expansion into nothing is impossible (or at least, "makes no sense," which I assume is a positive statement of impossibility), my point is proven. "Nothing" would seem to be the lack of something, or more precisely, "anything," while emptiness would appear to be the basis upon which all non-emptiness is formed. "Nothing" would translate to "no-thing" while emptiness is a thing of sorts. Whether or not that thing needs the dualism implied by both holder and time is another argument altogether. Singularity suggests the holder and the held are the same, and if so, then time is an artifice. Ultimately, you're right, I don't understand.

 

[neutron_star69]

i cant tell, are you being sarcastic?

 

[doorma]

If you can't tell, then I have obviously failed. No, I am not sarcastic as much as simply confused by the subject matter.

 

[neutron_star69]

oh lol it sounded like you were being a little sarcasttc in some parts. but im confused right along with ya.

 

[a_lost_packet_]

<font color="yellow">doorma - How can time exist in an infinite universe exept as finite artifice? The time it would take to travel to the end of the infinite universe and back is exactly the same amount of time it takes only to get half-way. </font><br /><br />"Travel" has as one of it's components, "Time." It's hard to define something using itself as a definition. <div class="Discussion_UserSignature"> <font size="1">I put on my robe and wizard hat...</font> </div>

 

[a_lost_packet_]

<font color="yellow">doorma - What, I wonder, does space expand in to? </font><br /><br />It doesn't expand in to anything. It doesn't expand into "nothing." It simply expands. Consider that our entire system of observation and measurement is defined by the Universe. Stepping outside of that set of laws and then attempting to analyze something while remaining true to them is tricky business at best. Doing so while maintaining "common sense" approaches can be hazardous to your health.<br /><br />Perhaps it would be easier to look at it from a different point of view. Consider that the "Universe" began and is expanding. Ignore the rest for now. Unless, of course, you want to discuss the possibilities of string theory or, my favorite, Ekpyrotic theory. Still, we are just beginning to learn the questions we need to ask. There's alot of questions to figure out yet. <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <font size="1">I put on my robe and wizard hat...</font> </div>

 

[neutron_star69]

how can space expand into nothing. space cant create space to expand into so it either is expanding into something or it is simply STRETCHING out.

 

[george_w]

It's like a growing child. Everything just gets bigger and bigger. Big like Texas.