It's at about 25 minutes in, for those wanting to watch.

Quote:On the opposite site of the planet from you. Big Grin

That's not much help. Which country,or are you too embarrassed to say?

Quote:Say, how do you blokes keep from falling off?

Aussies are smart enough to stay away from the edge.

(June 6, 2012 at 5:43 pm)rafa360 Wrote: I'm 15, my name is Rafael and I made a conclusion, for sure someone else arrived on the same thing (or maybe further) as the world is full of people... but I'm just sharing that for people to think about it or maybe show me something I didn't see...
so...

there is no end for the universe, right? so there is a infinite number of galaxies with a infinite number of planets,

our planet is pretty "lucky" in his position with the sun, some centimeters away : to cold, some cm near: to hot...
all this "perfection" make people believe in something else because it just can't be "luck"... but if there is a planet in this perfect position, there is a probability... (0.something 1)

let's say this probability is 0.000000000...000...0001
and how many 0 you want, its a very small number...
but remember that 0.0howmany0syouwant0.1 X (times) & (let's use & as infinite symbol because I don't have the symbol on my phone and its 3 a.m... XP) is always infinite:

0.00...000..000...001 X & = &
because a part of infinite is infinite, doesn't matter how small that is...

but there is always the time, which I also think is infinite a timeline is not like that
|___________________________________________|
is something like that
........_______________________________________........
so, no end, infinite number of billions of years
and as you know some millions of years ago the earth wasn't that good for life... so we take the probability that this planet with life is in this "good" time, which is 0.(tons of 0).1
something like that in our timeline
...._________________(-)___________________.....
remembering that this is a fraction of the infinite, a really, really small number... tons of 0s...

to know how many planets have life in this time we have to multiply our 2 numbers...

0.00...0...0...001 X 0.000....000...000...001

and that will do a smaller number than before, a 0. almost infinite 0s and 1... or if you prefer 1 in 9999999999999.....

a tiny, tiny number, but... who cares? its always bigger than 0, and anything bigger than 0 times infinite stills infinite... (my mind lost its virginity years ago...0.o)

and everything make me think that if there is a & number of planets better than ours, a & number of planets worse, older, yanger, nicer, identical... at ours.... well & number of planets out there... well, now I noticed I didn't arrive in any conclusion... I though I did ... 0.o I don't know... too late, can't think anymore... XP
anyways... it was good to write that... I'll keep that up to when I think in something else...

Look up "Drake's Equation"

Anyway, there are several assumption you made which is either not supported by our current understanding of the universe, or appear to directly contradict our understanding of the universe.

1. Universe as we know it, and therefore life operating according to fundamental rules of chemistry as we know them, definitely had a beginning, 13.7 billion years ago, and therefore has an beginning and does not go back infinitely into the past.
2. Our understanding of universe says its expansion will accelerate, and the force propelling the acceleration has already overwhelmed gravity on a very large scale, comparable in dimension to the observable universe. It will gradually overwhelm gravity on smaller and smaller scales, ripping apart first galaxy clusters, then galaxies, then star systems, then stars, then planets, etc. So planets as we know them won't last for ever. There will eventually be a time in the history of the universe when all stars and planets will not just burn out, but to exist to exist as coherent objects. The expansion of the universe will cause them to unbound gravitationally and fly apart. . Maybe future intelligent life would figure out a way for memory and thinking processes defining intelligent life to continue even through this. But short of this, we might say live bearing capacity of the universe as we know them will end some day.
3. It is not all together clear if the phyisical dimension of the entire universe has a limit. It is bigger than our observational horizon, but that doesn't mean it is infinite. One theory argues although you can never run off the edge of our universe, the dimensions of the universe loops back on itself so the total number of galaxies and stars and planets is finite.
4. It is also not clear if the universe is homogenous. It appears to be nearly homogenous within the portion we can observe. But we don't know how much lies beyond our observational horizon. We don't know if every part beyond our horizon look more or less like our part. It may be that not only is universe physically finite, but there maybe large portions of in which there are no planets or stars or conditions for life. There are some intriguing recent observations that does seem to suggest universe is not homogenous on a scale larger than our light horizon of 13.7 billion light years.

(June 6, 2012 at 7:31 pm)rafa360 Wrote:

(June 6, 2012 at 6:42 pm)padraic Wrote: Actually, nobody knows for sure.Without a demonstrably true premise,your inference (conclusion) may be logically valid,but may not be claimed to be true. Nice try though.

I'm going to do one soon...

anyway, I don't think anything is true (0.o daily mindf.... again) like any theory are only a theory and there is no evidence to make them true, some "know" their own truth and some just call it their faith or myth... every one of those theories can be true till someone shows a evidence for something else....
thanks

A theory is not a hypothesis as the layman usage of the term would have you think. A theory is a set of explanations, a framework of explanation, for empirically observable phenomena. Theories are supported by evidence and confirmed (insofar as science is able) through tests and experimentation.

(June 6, 2012 at 7:29 pm)Hovik Wrote: In that video I linked, Lawrence Krauss briefly discusses the shape of the universe and provides cursory evidence that it is, indeed, flat. However, I'm nowhere near qualified to say anything on the matter beyond taking his word for it.

Damn it Jim, I'm a linguist, not a physicist!

Yes, the evidence that we have today suggests that it is flat or nearly so. However, even future planned experiments will only be able to detect curvature greater than omega > +/- 10^-4.

So for now the answer is that, as far as we can tell, it looks pretty damn flat, but there's enough wiggle room such that we're not sure.

Personally, while I like the elegance of a flat (omega = 0) universe, I find it easier to wrap my brain around the idea of the boundless-yet-finite non-euclidean universe (omega =/= 0). Tomorrow I may feel differently. Neither is easy to contemplate.

(June 6, 2012 at 6:56 pm)Hovik Wrote:

(June 6, 2012 at 6:51 pm)rafa360 Wrote:

I'm not wholly equipped to answer your questions as well as I'd like, but I can tell you that there is an "edge" to the universe in some sense. The universe is simply a space that expanded during the big bang. Outside of that space there isn't really anything, so far as we know. There could be other universes alongside ours, but we really don't know right now.

The position of our planet around the sun is indeed the factor that determines its habitability, but the range of distance from the sun in which the Earth could remain habitable is quite large (as I've previously said).

You seem to have a natural curiosity for this kind of thing, so I encourage you to perhaps read some books on elementary physics or, if you've an hour or so to kill, watch this lecture by a physicist named Lawrence Krauss. It might not give you specific answers to your questions, but you would definitely learn a lot about the modern state of our understanding of the universe, how it came to be, how big it is, and how scientists are able to figure all of this stuff out.

http://youtu.be/7ImvlS8PLIo

I'll be watching that video soon.
I think you are well prepared, you just can't know that like all other mortals...
like you said "as far as we know" we may never know those things, maybe there is a universe of universes, maybe not...
I'm kind of curious about those things, universe, where we came from and where we are going to.... maybe too curious, maybe all that curiosity is going to kill me, or just leave me on a great depression...
all that bring me to the theme happiness... I think religious people are wrong for believing in everything they growed up listening, for sacrificing hours at week praying, for doing the good for other people not because they like or want to, but because they don't want to go to the Hell, for blaming people like gays or that have other cultures or religions...
BUT, I fell like, they a happier than I will never be a day, ok they don't live that life 100% thinking to the next one... but their are happy... and more delusional is to think that I may die without any answers, I (think) know that there is nothing after death...

(June 6, 2012 at 7:51 pm)Cthulhu Dreaming Wrote:

(June 6, 2012 at 7:29 pm)Hovik Wrote: In that video I linked, Lawrence Krauss briefly discusses the shape of the universe and provides cursory evidence that it is, indeed, flat. However, I'm nowhere near qualified to say anything on the matter beyond taking his word for it.

Damn it Jim, I'm a linguist, not a physicist!

Yes, the evidence that we have today suggests that it is flat or nearly so. However, even future planned experiments will only be able to detect curvature greater than omega > +/- 10^-4.

So for now the answer is that, as far as we can tell, it looks pretty damn flat, but there's enough wiggle room such that we're not sure.

Personally, while I like the elegance of a flat (omega = 0) universe, I find it easier to wrap my brain around the idea of the boundless-yet-finite non-euclidean universe (omega =/= 0). Tomorrow I may feel differently. Neither is easy to contemplate.

Interesting. I hadn't thought that there might be a resolution issue with respect to defining that flatness. I, too, appreciate the elegance of an omega = 0 universe, but appreciation of elegance of course does not lend validity. We'll just have to see what the latest in research can tell us.

(June 6, 2012 at 7:34 pm)padraic Wrote:

Quote:On the opposite site of the planet from you.

That's not much help. Which country,or are you too embarrassed to say?

Embarrassed, no. Easier to keep the joke on you rather than me, yes. Pacific NW USA.

(June 6, 2012 at 7:34 pm)padraic Wrote:

Quote:Say, how do you blokes keep from falling off?

Aussies are smart enough to stay away from the edge.

No, man, I mean you guys are freaking UPSIDE DOWN! You got gravity boots or something?

---

(June 6, 2012 at 7:55 pm)Hovik Wrote: Interesting. I hadn't thought that there might be a resolution issue with respect to defining that flatness. I, too, appreciate the elegance of an omega = 0 universe, but appreciation of elegance of course does not lend validity. We'll just have to see what the latest in research can tell us.

Absolutely.

And yes, the universe owes nothing to our sense of elegance. Frankly, I wouldn't be surprised if there was some curvature and that on a large scale was non-euclidean even though it appears to be on smaller scales. Much in the same way that at a quantum level things do not appear as they seem on larger scales.

Time will tell - and I hope that many of these questions are answered within my lifetime.

(June 6, 2012 at 7:42 pm)Chuck Wrote:

(June 6, 2012 at 5:43 pm)rafa360 Wrote: I'm 15, my name is Rafael and I made a conclusion, for sure someone else arrived on the same thing (or maybe further) as the world is full of people... but I'm just sharing that for people to think about it or maybe show me something I didn't see...
so...

there is no end for the universe, right? so there is a infinite number of galaxies with a infinite number of planets,

our planet is pretty "lucky" in his position with the sun, some centimeters away : to cold, some cm near: to hot...
all this "perfection" make people believe in something else because it just can't be "luck"... but if there is a planet in this perfect position, there is a probability... (0.something 1)

let's say this probability is 0.000000000...000...0001
and how many 0 you want, its a very small number...
but remember that 0.0howmany0syouwant0.1 X (times) & (let's use & as infinite symbol because I don't have the symbol on my phone and its 3 a.m... XP) is always infinite:

0.00...000..000...001 X & = &
because a part of infinite is infinite, doesn't matter how small that is...

but there is always the time, which I also think is infinite a timeline is not like that
|___________________________________________|
is something like that
........_______________________________________........
so, no end, infinite number of billions of years
and as you know some millions of years ago the earth wasn't that good for life... so we take the probability that this planet with life is in this "good" time, which is 0.(tons of 0).1
something like that in our timeline
...._________________(-)___________________.....
remembering that this is a fraction of the infinite, a really, really small number... tons of 0s...

to know how many planets have life in this time we have to multiply our 2 numbers...

0.00...0...0...001 X 0.000....000...000...001

and that will do a smaller number than before, a 0. almost infinite 0s and 1... or if you prefer 1 in 9999999999999.....

a tiny, tiny number, but... who cares? its always bigger than 0, and anything bigger than 0 times infinite stills infinite... (my mind lost its virginity years ago...0.o)

and everything make me think that if there is a & number of planets better than ours, a & number of planets worse, older, yanger, nicer, identical... at ours.... well & number of planets out there... well, now I noticed I didn't arrive in any conclusion... I though I did ... 0.o I don't know... too late, can't think anymore... XP
anyways... it was good to write that... I'll keep that up to when I think in something else...

Look up "Drake's Equation"

Anyway, there are several assumption you made which is either not supported by our current understanding of the universe, or appear to directly contradict our understanding of the universe.

1. Universe as we know it, and therefore life operating according to fundamental rules of chemistry as we know them, definitely had a beginning, 13.7 billion years ago, and therefore has an beginning and does not go back infinitely into the past.
2. Our understanding of universe says its expansion will accelerate, and the force propelling the acceleration has already overwhelmed gravity on a very large scale, comparable in dimension to the observable universe. It will gradually overwhelm gravity on smaller and smaller scales, ripping apart first galaxy clusters, then galaxies, then star systems, then stars, then planets, etc. So planets as we know them won't last for ever. There will eventually be a time in the history of the universe when all stars and planets will not just burn out, but to exist to exist as coherent objects. The expansion of the universe will cause them to unbound gravitationally and fly apart. . Maybe future intelligent life would figure out a way for memory and thinking processes defining intelligent life to continue even through this. But short of this, we might say live bearing capacity of the universe as we know them will end some day.
3. It is not all together clear if the phyisical dimension of the entire universe has a limit. It is bigger than our observational horizon, but that doesn't mean it is infinite. One theory argues although you can never run off the edge of our universe, the dimensions of the universe loops back on itself so the total number of galaxies and stars and planets is finite.
4. It is also not clear if the universe is homogenous. It appears to be nearly homogenous within the portion we can observe. But we don't know how much lies beyond our observational horizon. We don't know if every part beyond our horizon look more or less like our part. It may be that not only is universe physically finite, but there maybe large portions of in which there are no planets or stars or conditions for life. There are some intriguing recent observations that does seem to suggest universe is not homogenous on a scale larger than our light horizon of 13.7 billion light years.

yeah, but its everything "as we know now" few years ago we believed that the planet was flat, or the centre of the universe...
and how the universe can have a start in time? was there something before? what is this "nothing"? any gases? every thing just started, where the gases game from?
thanks

If you don't proceed from what we know, then you might as make up any shit you want.

The universe have a start because we can see it's developmental trend now, and using our understanding of physics, we can trace the development trend back in time to 13.7 billions ago. We can also observe direct evidence Of what happened 13.7 billion years ago. They agree. Before 13.7 billion years ago the universe was clearly so fundamentally different from what it is now that all of what we now coloquially take to be the symbols of the universe, planets, stars, galaxies, etc, can't exist. Most of the very elements of your body, carbon, iron, calcium, can't exist. Chemistry can't exist. Indeed prior to some point around 13.7 billion years ago Light can not propagate through space because the universe was opaque. As we see farther out we see farther back due to time taken by light to travel. When we look out 13.7 billion light years we look back 13.7 billion years. There we in fact see the very last second of the opaque universe as it turns translucent. This ghost image of opaque universe is called the cosmic background radiation. Look it up. So whatever came before was so different from our universe, we might as well say our universe started after that point.

Btw, you should know what the term gas means before asking whether gas came before Universe. Gas in science has a very specific meaning. If you don't know precisely what is meant by gas, what meaning could it have for you if you were told whether gas came before he universe?

What scientists call gas can not exist before 13.7 billion years ago. A small amount of time prior to that even atomic nucleus can not exist and the universe was an opaque soup of subatomic particles. Much beyond that we reach temperatures and densities that is as yet beyond the capacity of modern physics to accurately model. So the truth is we are not certain what came much before the beginning of the universe as we know it.