Is the universe infinite or finite?

Fonduman said:

the theory i was talking about states that matter warps space into itself, forming a kind of bubble. hence theres a limit to space.

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Yes, and I said I disagreed. In your case space ends, but that's an unproven theory. I think it's more common to assume space is euclidean except in the presence of matter.

current cosmological models say its isomorphic which colloquially means "same everywhere" which translates into "everyone anywhere in the universe perceives they are at the center". No one is "near the edge." Paradoxically to we 4-dimensional beings--who oft times have a hard time even with 3 dimensions--this still means there is no "boundary" but it *is* finite and it *does* have a "measurable" diameter!

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well, that would explain why my textbook agrees with me. it isnt definetly right, but its generaly taken as currently accepted/most likely

Fonduman said:

well, that would explain why my textbook agrees with me. it isnt definetly right, but its generaly taken as currently accepted/most likely

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I've seen with my own eyes two textbooks, printed in the same year. the first disagrees with string theory, ridiculing it as myth and fallacy and completely unproven. The second was putting string theory out implying it was proven incontrovertible fact. (one textbook belonged to my brother, the second to my cousin. There was a fascinating argument between them at a family reunion)

Simply because something is in a textbook in use at a university, doesn't mean it's therefore currently accepted. Textbooks can often reflex personal opinions of the authors, as well as the professor teaching the class who picked that textbook to begin with.

Since nobody has proven yet what space-time is, or how it is made, there are no real "currently accepted" theories as to if it is infinite or not. LOTS of supposition, which simply helps to fuel this interesting thread, but no theory strong enough to outshine all the others and gain acceptance in the scientific community.

Don't know about the universe but I predict this thread is finite.

Lol tabish-and as for textbooks, I once saw a "christian-approved" homeschool textbook that made me want to vomit. Everything in there was a blatant lie. They said magnets were metal with gravity stuck inside them, that nobody knew where electricity came from, and said that if the sun was really that big it would suck in the earth. FUUUUUUU They also used some example where they were like "so let's say meteorites put .0001 inches of dust on the moon every year. An evolutionist would say that there would be millions of inches of dust on the moon, while a christian would say there was an inch. It's clear who was right after the astronauts walked on the moon." :banghead::banghead:

One thing that's certain ... we will never know if it's endless or not.

A lot of this stuff is related to time as well. Is it something that actually travels or does no time actually pass by, meaning only the atoms move around from place to place

Crazy Jay said:

One thing that's certain ... we will never know if it's endless or not.

A lot of this stuff is related to time as well. Is it something that actually travels or does no time actually pass by, meaning only the atoms move around from place to place

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We will most likely find out very soon. Think about it, 99% of our modern physics understanding and tech comes from the past 250 years. That's .008% of our ~3 million years as homo sapiens. We will discover at an even more accelerated rate now due to the advent of computers. I imagine we will know most of what there is to know about the universe in the next thousand years or so, barring a nuclear war or evolutionary degeneration or something. Long range space travel is very near, and I'm sure things that we consider preposterous right now like time travel or FTL (perhaps neither, but we will think of some things no one can imagine right now) will be available in not too many thousands of years. And the whole time thing is another argument... a very complex one.

Fonduman said:

matter curves all of space into itself, forming a kind of space bubble. however, you cannot reach the "edge" of it.

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If all space curved, wouldn't this be measurable? Just by generic objects, anywhere? If we know what to look for we can see signs of a round earth from our daily life.

And more importantly, as someone of you said earlier about other life in the universe is being unavoidable; Do you think they have made lasers? :shhh:

My personal feeling is that the universe is finite, yet so large as to approach infinity( you know like when you studied limits in calculus). My other point of view, is based on the idea of what a finite sized computer (the human brain), can calculate especially when given input from our finite set of sensors. IE, eyes, ears, nose, touch. I mean where are our senses when it comes to verifying 5 dimensions, 10 dimensions...............infinite dimensions? It's hard to comprehend that which approaches the infinite in complexity with such a limited set of tools that we have at our disposal.

Then again if we use the cereal model and stack cheerios into a matrix that is 14" X 12" X 3", Niko will apply the finite cereal theorem to solve for the solution of finite < infinite. ;-) Hope that forest fire in Buenos Aires is put out soon Niko.

mhakali said:

If all space curved, wouldn't this be measurable? Just by generic objects, anywhere? If we know what to look for we can see signs of a round earth from our daily life.

And more importantly, as someone of you said earlier about other life in the universe is being unavoidable; Do you think they have made lasers? :shhh:

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i think they have taken some measurements based on the curvature of light or something like that, and concluded the universe is ~156 billion light-years wide

156 billion LY is the diameter of all known MATTER in the universe, not some giant universe bubble. That seems big, considering the age of the universe but that's what my google-fu said.

makes sense that if space was curving into itself as a result of the matter, that space would not extend too far beyond the outer parts of matter. after all, gravity weakens significantly less than a lightyear beyond most large bodies.

I have wondered many times, how it is remotely possible to actually claim the universe KNOWN diameter is larger then double the maximum distance we can directly see.... =/ I wish those textbooks out there would stick to stop calling theory fact even when it IS generally believed. Bottom line is the diameter of the matter that we theorize is unproven. We can assume given this and that, that so and so is valid. However, it's still an assumption. There is still a LOT we don't know about even what we can observe.

Recent discoveries have proven while you can't actually break the speed of light with matter directly, there ARE some loopholes around it that work. Loopholes that could form naturally. At Los Alamos lab they have generated something like an electromagnetic pulse that behaves like it's FTL. Interesting effects, one of which was the radiation emitted didn't decay at the inverse square of the distance anymore. Simple changes like that throw off all kinds of math calculations based on some things being universal constants. If you change the basic concepts the higher math is founded upon, then all the more complicated calculations will turn out way off.

I don't believe we really know half as much about the universe as we think we know. Though I agree our knowledge and understanding will continue to advance at an exponential rate. Things will most certainly be more interesting in a year or two. Just think of the handheld portable diode lasers we will have just 10 years from now. Given diodes seem to be following moore's law now.... >

also, perhaps we shouldnt jump to conclusions even based on what we do know. like, "we cannot travel faster than light, therefore it will take years to reach anywhere". and then they figured out, "ah, but what if we shorten the distance?" lol

Fonduman said:

makes sense that if space was curving into itself as a result of the matter, that space would not extend too far beyond the outer parts of matter. after all, gravity weakens significantly less than a lightyear beyond most large bodies.

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The whole gravity weakens significantly thing is a vague comment.... gravity weakens proportionally to the inverse square of distance, it's not like after a lightyear it drops off. And space doesn't curve into itself as a result of matter, matter warps spacetime but where there is no matter space and time behave very simply according to (we think) euclidean geometry. And at what point does space drop off after matter? According to your argument matter warps space so that space stops, but the farther away from matter you go the less warping effect it has.

Fonduman said:

also, perhaps we shouldnt jump to conclusions even based on what we do know. like, "we cannot travel faster than light, therefore it will take years to reach anywhere". and then they figured out, "ah, but what if we shorten the distance?" lol

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The problem is they haven't figured anything out.... we have no idea how to shorten the distance. High-speed travel is actually very convenient for the travelers, if you can get to .86c, time will move half as fast aboard the craft IIRC and if you get going faster time will slow more, making travel seem quick to the travelers. And shortening the distance between two objects is iffy, because the ways that some people think that would work violate thermodynamics.

StridAst said:

I have wondered many times, how it is remotely possible to actually claim the universe KNOWN diameter is larger then double the maximum distance we can directly see.... =/ I wish those textbooks out there would stick to stop calling theory fact even when it IS generally believed. Bottom line is the diameter of the matter that we theorize is unproven. We can assume given this and that, that so and so is valid. However, it's still an assumption. There is still a LOT we don't know about even what we can observe.

Recent discoveries have proven while you can't actually break the speed of light with matter directly, there ARE some loopholes around it that work. Loopholes that could form naturally. At Los Alamos lab they have generated something like an electromagnetic pulse that behaves like it's FTL. Interesting effects, one of which was the radiation emitted didn't decay at the inverse square of the distance anymore. Simple changes like that throw off all kinds of math calculations based on some things being universal constants. If you change the basic concepts the higher math is founded upon, then all the more complicated calculations will turn out way off.

I don't believe we really know half as much about the universe as we think we know. Though I agree our knowledge and understanding will continue to advance at an exponential rate. Things will most certainly be more interesting in a year or two. Just think of the handheld portable diode lasers we will have just 10 years from now. Given diodes seem to be following moore's law now.... >

Click to expand...

can I have a link to the los alamos thing? And an "easy" way to get to the speed of light is getting rid of "god particles" (mass particles) if we can find them. The problem is slowing from the speed of light....

The problem is they haven't figured anything out.... we have no idea how to shorten the distance. High-speed travel is actually very convenient for the travelers, if you can get to .86c, time will move half as fast aboard the craft IIRC and if you get going faster time will slow more, making travel seem quick to the travelers. And shortening the distance between two objects is iffy, because the ways that some people think that would work violate thermodynamics.

Click to expand...

well, length contraction does occur, thats why it seems quicker than it should. or, atleast thats an explanation of the seeming quickness to the people in the spaceship, to whom they are running at a normal time rate. one thing i've learnt is theres often several approaches that reach the same conclusion
but yeah, i was refering more to the idea of black holes warping space enough to contract distance and all that. you are picking over the validity of what im saying as though im trying to prove a theory, but i was just giving an example of what could be possible in order to demonstrate my point.