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thivitaaBest ResponseYou've already chosen the best response.0
i dont think our universe really have an edge...
 one year ago

harsh314Best ResponseYou've already chosen the best response.2
if we look on it practically as we know the universe is expanding and the edge of the universe depends on that expansion we can say that the edge of the universe is continuously changing and also the edge depends upon the shape of space matrix all around but still as we know dark energy is responsible for expansion so it depends on the behaviour of dark energy as if it obeys the law of conservation of energy then the rate of expansion of the universe would be exactly same everywhere and hence every part would expand in a symmetrical way now if we consider the whole universe as a large system with conserved energy then its orignal shape must be spherical and hence we can say the universe is expanding in spherical symmetry so it will have no edge
 one year ago

amistre64Best ResponseYou've already chosen the best response.0
i kinda have to wonder what defines an "edge" for the universe
 one year ago

Sidhantb5Best ResponseYou've already chosen the best response.0
if multiverse' exist then no universe may have an edge
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
dw:1349878917681:dw
 one year ago

FathomspaceBest ResponseYou've already chosen the best response.0
If considering the universe a sphere in totality,then i guess the universe wouldnt have an edge.Just like earth....And any mass in space tries to occupy minimum volume,so i guess the universe is pretty much a sphere.
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
Its not a perfect analogy though, more of a metaphor I think. If the universe was a true sphere then traveling in one direction I would eventually get back to where I started, which I don't believe is the case.
 one year ago

paarthBest ResponseYou've already chosen the best response.0
the answer to this question would depend on how you define "universe". if by "universe" u mean the observable universe , then the answer would be a yes . the observable universe is quite understandably expanding (or its edge is moving away) at the speed of light. if you are talking about the complete "universe" (which is not very well defined) , recent experiments have shown that its topography is more or less flat(and which implies it is endlessly extending). moreover, you may involve the concept of multiverses which will make the topic even less specific and less answerable. so, all in all it depends on what you mean by the term "universe"
 one year ago

Sidhantb5Best ResponseYou've already chosen the best response.0
paarth what do we mean by complete universe? is it a multiverse?
 one year ago

paarthBest ResponseYou've already chosen the best response.0
that's what i said. it is not defined and, probably, will never be. so for all practical purposes ( which won't be very much practical in the present or the near future)we can use the observable universe which, yes, does have an edge expanding at the speed of light.
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
universe have an edge as its just asystem having limited energy.
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@009infinity how are you defining 'edge?'
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
it is expanding till now but its edge is expanding with a constant rate.
 one year ago

ujjwalBest ResponseYou've already chosen the best response.0
If universe began from a point and immediately after bigbang began to expand and is expanding, it must have an edge.. Saying that something which 'doesn't have edge' is expanding doesn't make sense at all.. So. if you say the universe is expanding you must say that it has an edge which is expanding along with its expansion! But that's too classical and simple explanation.. maybe it isn't that simple.. but that's what i think!
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@009 you mean the edge of the observable universe, the light horizon, not the actual universe itself.
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@ujjwal that misconception comes from thinking that the universe is expanding into empty space, but all space (empty or not) is within the universe.
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
its ur misconception @CliffSedge as energy creates space and time and definetly space is within the universe.
 one year ago

ujjwalBest ResponseYou've already chosen the best response.0
So, how is the universe expanding? Expanding refers to gradual increase in size.. If it doesn't have a size, how can its size increase?
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
let me give you a hint our universe have boundaries proved by holographic principle, so this boundary can store information on its walls
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@009 how is that my misconception? You didn't say anything that is in disagreement with what I said.
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@rv, that is still not a physical boundary. These 'walls' you speak of don't exist anywhere.
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
the way I was told to imagine it is a balloon. imagine the 2d surface of the baloon is our 3d space. as the balloon is inflated that 2d surface expands, but still has no edge
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@ujjwal "So, how is the universe expanding? Expanding refers to gradual increase in size.. If it doesn't have a size, how can its size increase?" The expansion is the increase in distance between galaxies. The Big Bang did not occur at a point and then a small universe got bigger. The Big Bang occurred everywhere at the same time. The universe is either infinite or finite (this is unknown, my guess is finite). What ever its finitude at the time of the Big Bang, it is the same now. Expansion occurs everywhere equally.
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@JamesWolf yes, that can help visualize details of the expansion, but since people can't visualize expanding 4dimensional spacetime, it can be a misleading analogy.
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
Its a really hard one to visualise. Like trying to imagine viewing all of 4d space at once. rather than just 3d spaces with slices of the 4th dimension (time).
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
this is a fact that our universe have boundaries. on which it can store the information the most basic physics principle that information can never be lost e.g., if a star dies it must leave some information in the universe as a residue, where does this information goes is the boundaries of the universe so whats ur ans now?
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
dw:1349890021663:dw
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
My answer is that I dont understand the holographic principle well enough to comment.
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
bloody good drawing considering the shocking software on here
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
its some what like that time is 4th dimension
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@rvgupta I do understand the holographic principle, but you are still imagining that there is a physical wall somewhere that encodes information on a 2D surface. I recommend studying the topic further. Leonard Suskind has some good explanations. It is related to black hole physics as well, so spend some time with that.
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
"if a star dies it must leave some information in the universe as a residue, where does this information goes is the boundaries of the universe" When a start dies, its 'information' is in the form of the matter that it was made of, that matter still resides in the space the star was in.
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
if u people r talking about expansion then let me tell u that it depends on the latest theory INFLATION which predicts that universe expansion rate is continuously increasing even faster than the speed of light so its impossible to say that whether our universe is finite or infinite
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
That is NOT the theory of inflation
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
Some casual reading: http://io9.com/5818008/theuniverseprobablyisntagianthologramafterall
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@rvgupta (leaving aside your rude tone for now) "if u people r talking about expansion then let me tell u that it depends on the latest theory INFLATION which predicts that universe expansion rate is continuously increasing even faster than the speed of light so its impossible to say that whether our universe is finite or infinite" This is false. Inflation theory isn't a prediction, it is a model of cosmic dynamics shortly after BB. The increase in expansion rate now is unrelated. No matter travels faster than light, but the space between matter can expand at any rate. You are correct that it is not yet known whether the universe is finite or infinite, but regardless of which, there is still no boundary.
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
Some more casual reading: http://www.cfa.harvard.edu/seuforum/faq.htm#s1
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
so what about the information lost
 one year ago

ujjwalBest ResponseYou've already chosen the best response.0
What does "information" refer to? @rvgupta
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
what information loss? when a star explodes the information is taken from all the parts that fly off isnt it? if time is reversed you get the star back. no information is lost?
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
it is the most basic principle of physics that information can never be lost so it must be somewhere based on this susskind said that our universe must have boundaries to store this information, even stephen hawkink said that it should be right
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
I dont think you understand it, (im not saying i do). explain to me where the information is lost? Hawking showed that information was not lost in a black hole, since a black hole evaporates?
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
what do u think about parallel universe this theory is useless without boundaries
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
Yeah, I'm not seeing the information loss either. Are you talking about black holes?
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
i think information is not lost till we exist to precieve it
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
I don't think you understand 'parallel universes' or multiverse theory either, rvgupta..
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
@CliffSedge can u explain
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
the old does a bear pellet in the woods theory infinity? :P
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@009infinity 'information' (in physics) is not the same as knowledge. Information is due to signals (relative motion or other interactions of matter and energy).
 one year ago

ujjwalBest ResponseYou've already chosen the best response.0
I just understood that i understand nothing! Carry on Young Scientists!!
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
The multiverse is not like universes physically stacked on top of each other as if they were sheets of paper. The multiverse is a sumoverhistories of all the possible interactions that could occur in given instances.
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@ujjwal congratulations, you are at least as wise as Socrates! :)
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
As much as I would love to continue this discussion all day, I have to leave for work in like 5 minutes, so we can pick this up some other time if you are still interested.
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
information will exist before time is over am i right now
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
I don't know what that means, @009infinity "before time is over" ??
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
cliff u r now talking about parallel universe not multiverse
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
The multiverse *is* parallel universes. It's the same thing, @rvgupta
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
@CliffSedge there r two sence of it that inoformation will exist in universe till time exist (before big crunch)& second its too long discussion to over it
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
"@ujjwal congratulations, you are at least as wise as Socrates! :)" The oracle would like you :)
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
parallel universes are supported by string theory so dont say that they r same
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@009infinity "there r two sence of it that inoformation will exist in universe till time exist (before big crunch)& second its too long discussion to over it" There is no 'Big Crunch.' The universe will likely go on expanding forever and time will not end.
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
Yes, @rvgupta I understand the inflationary model. It does not support anything you are saying about boundaries. Regardless of what String Theory (a theory that makes no predictions, explains nothing, and has not been tested) says about parallel universes, that has nothing to do with parallel universes and the multiverse meaning the same thing. You are profoundly confused; please do some more studying on the matter.
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
is there any evidience for that @CliffSedge
 one year ago

FellowrootBest ResponseYou've already chosen the best response.0
The universe can be thought of as a sphere expanding in all directions with the passage of time. Because of inflation, the universe was able to expand faster than the speed of light. When we look out into the universe you would think that we would be able to find an edge, but we can't because the universe is bigger than the range in which we can see. Because light is finite we can only see so far out into the universe, the reason why we can't past this is because light hasn't had enough time to reach us yet. Then there are other ideas about the universe being a multiverse and pocket universes, but that's another story.
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
http://en.wikipedia.org/wiki/Dark_flow is an interesting mystery regarding the "uniformity" created during the inflation period.
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
cliff do u want to say that im a fool
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
but i also have who will prove first u or i @CliffSedge
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
I'm sorry, I provided a bad link to a David Deutch article. I still recommend his book, The Beginning of Infinity.
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
''that is created must be destroyed" here is the proof
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
I dont think cliff is calling you a fool. i just dont think we understand these theories. Its easy to just regurgitate what good scientists say but until we get in there and start understanding the equations we really dont know what were talking about
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@rvgupta , I am not interested in discussing whatever words you are trying to put in my mouth.
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@009infinity "''that is created must be destroyed" here is the proof" That is a pithy statement without meaning.
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
so is there any conclusion
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
Conclusion (based on best current science): The universe is finite and without boundary.
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
"Does our universe have an edge? if yes. Explain" No
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
would u people like to discuss it tomorrow
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
Sure though i cant really add much
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
i will surely give u some astonishing proofs
 one year ago

009infinityBest ResponseYou've already chosen the best response.0
i m ready for genune ones ;)
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
To count as "astonishing proofs' I will need to see observational data confirmed by at least one other independent source, references to peerreviewed journals, and any theoretical explanations must be annotated with statements of falsifiability, and relevant criticism from professional scientists. Good luck!
 one year ago

JamesWolfBest ResponseYou've already chosen the best response.1
setting the bar low then... :P
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@JamesWolf Yes, but ya' know, this is only OpenStudy, nothing serious.
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
what time do u decide to discuss then
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
I don't know. I log on onceinawhile when I'm not busy with other stuff. If I don't go out later after work, then I might be back on around 02:00 GMT tomorrow.
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
r u ready 2 hours before this time
 one year ago

mayankdevnaniBest ResponseYou've already chosen the best response.0
good question but answer is no
 one year ago

mayankdevnaniBest ResponseYou've already chosen the best response.0
http://nerdfighteria.info/index.php?title=The_Universe_Has_NO_EDGE!
 one year ago

mayankdevnaniBest ResponseYou've already chosen the best response.0
scroll up and go through the link
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
i have read that all and they can be true but some theories like M theory predicts that our universe is not only the universe and it can have edge however this theory is still unproven
 one year ago

twitterBest ResponseYou've already chosen the best response.0
I don't believe in M and String theory. all of that are hocus pocus. It is more toward mathematics and philosophy or pseudoscience rather than physics. If you can't experiment with it, it just a beautiful guess.
 one year ago

twitterBest ResponseYou've already chosen the best response.0
There is one feature I notice that is generally missing in M and String Theories. It's a kind of scientific integrity, a principle of scientific thought that corresponds to a kind of utter honesty — a kind of leaning over backwards. For example, if you're doing an experiment, you should report everything that you think might make it invalid — not only what you think is right about it; other causes that could possibly explain your results; and things you thought of that you've eliminated by some other experiment, and how they worked — to make sure the other fellow can tell they have been eliminated. Details that could throw doubt on your interpretation must be given, if you know them. You must do the best you can — if you know anything at all wrong, or possibly wrong — to explain it. If you make a theory, for example, and advertise it, or put it out, then you must also put down all the facts that disagree with it, as well as those that agree with it. There is also a more subtle problem. When you have put a lot of ideas together to make an elaborate theory, you want to make sure, when explaining what it fits, that those things it fits are not just the things that gave you the idea for the theory; but that the finished theory makes something else come out right, in addition. In summary, the idea is to try to give all of the information to help others to judge the value of your contribution; not just the information that leads to judgment in one particular direction or another.
 one year ago

twitterBest ResponseYou've already chosen the best response.0
That's why I dislike someone who came with a theory that claim something so big yet so little prove. When asked the prove, they say "Oh just believe in me. Because this theory is SOOO beautiful." It's like a religion really. No wonder people have less honour about physics now. M and String theory are not science yet they promote it as is.
 one year ago

twitterBest ResponseYou've already chosen the best response.0
It is crazy, nonsense, and the wrong direction for physics. It is new version of medieval theology, and I wish to keep string theorists out of physics.
 one year ago

twitterBest ResponseYou've already chosen the best response.0
The entire mainstream modern physics band waggon has ignored REAL PHYSICSTS for simplicity and understanding what is known for sure, and has gone off in the other direction (magical unexplainable religion) and built up a 10 dimensional superstring model whose conveniently ‘explained’ CalabiYau compactification of the unseen 6 dimensions can take 10500 different forms (conveniently explained away as a ‘landscape’ of unobservable parallel universes, from which ours is picked out using the anthropic principle that because we exist, the values of fundamental parameters we observe must be such that they allow our existence).
 one year ago

twitterBest ResponseYou've already chosen the best response.0
… I do feel strongly that this is nonsense! … I think all this superstring stuff is crazy and is in the wrong direction. … I don’t like it that they’re not calculating anything. I don’t like that they don’t check their ideas. I don’t like that for anything that disagrees with an experiment, they cook up an explanation … All these numbers [particle masses, etc.] … have no explanations in these string theories – absolutely none!’
 one year ago

twitterBest ResponseYou've already chosen the best response.0
Besides, what is really there in string is not mathematical beauty, rather, it is mathematical ugliness and scientific failure.
 one year ago

twitterBest ResponseYou've already chosen the best response.0
Moreover, string theory is NOT even wrong because it does not provide any testable predictions. it has nothing statistical to back it up therefore it is not a valid scientific theory, it is non falsifiable as it currently stands, thus it is not even wrong, it's closer to philosophy atm; that to my mind is uncontestable; if you can show me evidence of string theory then I'll change my mind. Thus for someone to make an argument based upon M theory is just stupid.
 one year ago

twitterBest ResponseYou've already chosen the best response.0
In conclusion: String and M theories are in the same category with intelligent design, religion, philosophy. They are in a basket or branch of CRAZY department.
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
the universe has an edge like a cloud , the universe is where all the energy and matter exist, at the 'edge' is where there concentration of energy and matter diminishes to zero this is a fuzzy boundary
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.0
dw:1349962712340:dw
 one year ago

rvguptaBest ResponseYou've already chosen the best response.0
it somewhat depends on the shape of the universe whether its shape is spherical and like slices of breads proposed by some scientists
 one year ago

CliffSedgeBest ResponseYou've already chosen the best response.0
@twitter , I love you.
 one year ago

twitterBest ResponseYou've already chosen the best response.0
Hey man love you too. screw string theory. It degrades physics.
 one year ago
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