Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Webo on 04/12/2009 01:26:39
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As I understand the big bang theory, from a singularity the universe expanded at or above the speed of light for some period time, then slowed and is now again speeding up the expansion. That said as with a normal explosion - all thing moving outward somewhat evenly in all direction. If you turn the arrow of time then backward all things move back to the center of the explosion. So in other words even if all objects in space are moving away from each other as space expands, somewhere logically it all started as a singularity and all things move out in all directions somewhat evenly so again why no center of the universe? Is it that the universe is just to expansive for us to get a handle on and move the arrow of time backwards to the center? Or is it more like the string theory and we had two bains slamming into each other which created all the space at the same time and not from a singularity?
Thanks
Webo
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Our universe is infinite in the sense that no observer (in theory or practice) can detect an edge or the proximity of an edge. Instead there will be a horizon beyond which no communication is possible. Outside universes there are no observers, so the question of whether it is "actually" infinite is immaterial. Infinity is only a limit rather than a quantity anyway, so the absence of a boundary is all it takes.
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Imagine trying to find the center of a circle with no limit on perceivable size. You can't. That's why it's meaningless to even think of centers when it comes to the universe.
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Our universe is infinite in the sense that no observer (in theory or practice) can detect an edge or the proximity of an edge. Instead there will be a horizon beyond which no communication is possible. Outside universes there are no observers, so the question of whether it is "actually" infinite is immaterial. Infinity is only a limit rather than a quantity anyway, so the absence of a boundary is all it takes.
Whilst this is true, it doesn't quite answer this correctly. It's best to say the universe does not have a center because big bang happened in every smallest space and time in the vacuum; this would mean that objects are inexorably and concurrently moving further away from each other not because of a central expansion, but one which encompasses the expansion of spacetime in all of its arena.
As doctor fred Alan Wolf once said, ''We now believe they gang-banged into existence.''
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As I understand the big bang theory, from a singularity the universe expanded at or above the speed of light for some period time, then slowed and is now again speeding up the expansion. That said as with a normal explosion - all thing moving outward somewhat evenly in all direction. If you turn the arrow of time then backward all things move back to the center of the explosion. So in other words even if all objects in space are moving away from each other as space expands, somewhere logically it all started as a singularity and all things move out in all directions somewhat evenly so again why no center of the universe? Is it that the universe is just to expansive for us to get a handle on and move the arrow of time backwards to the center? Or is it more like the string theory and we had two bains slamming into each other which created all the space at the same time and not from a singularity?
Thanks
Webo
Also webo friend, direction of time, it seems does not exist at all!
Time Theory
A Verbal Proof of No Time Directionality To have a direction ...
www.scribd.com/doc/21379144/Time-Theory
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...as with a normal explosion - all thing moving outward somewhat evenly in all direction. If you turn the arrow of time then backward all things move back to the center of the explosion. So in other words even if all objects in space are moving away from each other as space expands, somewhere logically it all started as a singularity and all things move out in all directions somewhat evenly so again why no center of the universe?
Thanks
Webo
This is how I understand it, but I could be wrong: Imagine the universe as represented by an inflated balloon which has spots drawn all over it to represent the galaxies. When you deflate the balloon, all the spots move inwards towards a central point. Physically, the deflated balloon exists inside a room, but in reality the entire universe has just collapsed in on itself and there is nothing outside it to act as a reference point, therefore no centre.
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...as with a normal explosion - all thing moving outward somewhat evenly in all direction. If you turn the arrow of time then backward all things move back to the center of the explosion. So in other words even if all objects in space are moving away from each other as space expands, somewhere logically it all started as a singularity and all things move out in all directions somewhat evenly so again why no center of the universe?
Thanks
Webo
This is how I understand it, but I could be wrong: Imagine the universe as represented by an inflated balloon which has spots drawn all over it to represent the galaxies. When you deflate the balloon, all the spots move inwards towards a central point. Physically, the deflated balloon exists inside a room, but in reality the entire universe has just collapsed in on itself and there is nothing outside it to act as a reference point, therefore no centre.
Except, and you are wrong on this occasion, that time-reversibility for particle systems do not obey the classical.
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Nice one Fozzie.
The analogy is not bad but we have to remember that it is layer on layer on layer as the balloon can be seen as a 'two dimensional' description of a three dimensional reality.
http://math.ucr.edu/home/baez/physics/Relativity/GR/centre.html
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Nice one Fozzie.
The analogy is not bad but we have to remember that it is layer on layer on layer as the balloon can be seen as a 'two dimensional' description of a three dimensional reality.
http://math.ucr.edu/home/baez/physics/Relativity/GR/centre.html
Sorry... what? I wonder... if i can actually manage sometimes to try and remain scientific when i have people like yourself coaching on psuedoscientific ideologies. Now don't get me wrong, i love to think outside the box, but i pointed out that he or she was wrong. I don't need yourself to say erreneous things like ''nice one fozzie'' - when there was nothing correct about the proposal. By doing this, you are intentionally-misleading people.
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Nice one Fozzie.
The analogy is not bad but we have to remember that it is layer on layer on layer as the balloon can be seen as a 'two dimensional' description of a three dimensional reality.
http://math.ucr.edu/home/baez/physics/Relativity/GR/centre.html
Sorry... what? I wonder... if i can actually manage sometimes to try and remain scientific when i have people like yourself coaching on psuedoscientific ideologies. Now don't get me wrong, i love to think outside the box, but i pointed out that he or she was wrong. I don't need yourself to say erreneous things like ''nice one fozzie'' - when there was nothing correct about the proposal. By doing this, you are intentionally-misleading people.
WHAT?!
Mr Scientist, you promulgate your speculations as as if they were fact, and now you accuse others of intentionally trying to mislead people.
Perhaps you should reconsider your comments.
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Nice one Fozzie.
The analogy is not bad but we have to remember that it is layer on layer on layer as the balloon can be seen as a 'two dimensional' description of a three dimensional reality.
http://math.ucr.edu/home/baez/physics/Relativity/GR/centre.html
Sorry... what? I wonder... if i can actually manage sometimes to try and remain scientific when i have people like yourself coaching on psuedoscientific ideologies. Now don't get me wrong, i love to think outside the box, but i pointed out that he or she was wrong. I don't need yourself to say erreneous things like ''nice one fozzie'' - when there was nothing correct about the proposal. By doing this, you are intentionally-misleading people.
WHAT?!
Mr Scientist, you promulgate your speculations as as if they were fact, and now you accuse others of intentionally trying to mislead people.
Perhaps you should reconsider your comments.
Difference between me and you, is that i made it clear it was a ''speculation'' rather than one being mainstream. Tell me how your original post gave that impression? If anything, you are argeeing with someone i am assuring they are wrong. You jumping in and saying things like that projects the wrong kind of education.
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Difference between me and you, is that i made it clear it was a ''speculation'' rather than one being mainstream. Tell me how your original post gave that impression? If anything, you are argeeing with someone i am assuring they are wrong. You jumping in and saying things like that projects the wrong kind of education.
Mr Scientist,
You have posted non-mainstream ideas without making it clear they are speculation. This could easily mislead people. I have asked you to clarify the source of those ideas, which you did. But I certainly did not make pejorative and inflammatory comments like "pseudoscientific ideologies" and "intentionally misleading people" as you did above. Had I made such comments, I'm sure you would have been quite indignant, and for good reason.
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Difference between me and you, is that i made it clear it was a ''speculation'' rather than one being mainstream. Tell me how your original post gave that impression? If anything, you are argeeing with someone i am assuring they are wrong. You jumping in and saying things like that projects the wrong kind of education.
Mr Scientist,
You have posted non-mainstream ideas without making it clear they are speculation. This could easily mislead people. I have asked you to clarify the source of those ideas, which you did. But I certainly did not make pejorative and inflammatory comments like "pseudoscientific ideologies" and "intentionally misleading people" as you did above. Had I made such comments, I'm sure you would have been quite indignant, and for good reason.
Once you asked me to recite a reference, and the reference was of Prof. Hawking Himself.
How more mainstream are you wanting? Or is it the case that just because you had not heard the theory where there is no information loss, be it that you assumed it was not?
In which case, you are wrong.
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Mr Scientist,
It was not my intention to confuse you. If I did, I apologize.
The non-mainstream ideas to which I refer are in regard to relativistic effects regarding atoms versus "macroscopic bodies" (your terminology).
If Hawking has expressed an opinion on this matter I would most certainly review it.
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You must be clear then.
In this case... yes...ofcourse its not mainstream. I have yet to see an organic lifeform travel at relativistic speeds. A question i bet many have on their minds.
I do not question the validity of relativity, oh no sir-ree. If you think i am ATM by saying i am still waiting for a human to move relativistically next to a twin on earth, then that's not against the mainstream, that is a point view, for i never denied wholey that extreme time-delay would be found. I just want experimental proof that organic lifeforms with their bodies do indeed age, it is only by theory so far we believe it can.
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You know, without making any direct contentions on it, i'd like to warn anyone in this century that things in physics will change but it will never change intuitively. Everytime we think we know something, that something surprises us all.
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As I understand the big bang theory, from a singularity the universe expanded at or above the speed of light for some period time, then slowed and is now again speeding up the expansion. That said as with a normal explosion - all thing moving outward somewhat evenly in all direction. If you turn the arrow of time then backward all things move back to the center of the explosion. So in other words even if all objects in space are moving away from each other as space expands, somewhere logically it all started as a singularity and all things move out in all directions somewhat evenly so again why no center of the universe? Is it that the universe is just to expansive for us to get a handle on and move the arrow of time backwards to the center? Or is it more like the string theory and we had two bains slamming into each other which created all the space at the same time and not from a singularity?
Thanks
Webo
I think that a lot of the confusion is due to only thinking of the spatial aspects of the Big Bang. While it may seem reasonable to ask where the center of a three dimensional volume is located, this ignores the temporal dimension; you should also be asking 'where is the center of time'.
Now from our point of view, the universe is about 14 billions years old, so if we define the center of time as being the middle point then we'd say that the center of time is 7 billion years ago, which is not only pretty meaningless but is also only applicable to now; when the universe was younger, let's say 10 billion years old, the 'center' would have been five billion years before then, or five billion years after the BB, and we can extrapolate this into the future to say that when the universe is forty billion years old its center will be in our future i.e. 20 billion years after the BB. A pretty meaningless deduction, I think you'll agree.
It's necessary then, to think in four-dimensional space-time, at the very least.
There there's the issue of how can something that has infinite size have a center?
When you look into how much space there is in an n-dimensional environment you find that there is infinite n-1 dimensional space within an n-dimensional environment e.g. there is room for an infinite two-dimensional area within a finite three-dimensional volume, just as there is room for an infinite length one-dimensional line within a finite two dimensional area (as the line is one-dimensional it has no width, so you could imagine drawing it in tightly packed folds, with each 'fold' being infinitely close to, but not touching the preceding fold; the same applies for the two-dimensional area within a finite three-dimensional volume).
In our four-dimensional space-time then, which seems to be finite i.e. it's only 14 billion years old, there would appear to be room for infinite three-dimensional space, which being infinite, cannot have a center.
About the best we can do then, is to say that the universe doesn't have a center, but had an origin, and that origin is located about 14 billion years ago.
In the Randall-Sundrum model, the branes you refer to are analogous to four-dimensional areas slicing through through a five-dimensional volume.
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why no center of the universe?
IMHO, because the universe is infinite and infinities have no center. Just my opinion, no opinions are ever cast in stone!
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The majority of scientists believe there was a beginning, a Big Bang.If the BB started as an infinitely small point and expanded then the location of that point must still exist with respect to all the material expanding away from it.Of course finding that point from our perspective location is impossible but that does not mean the original point does not exist.
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The majority of scientists believe there was a beginning, a Big Bang.If the BB started as an infinitely small point and expanded then the location of that point must still exist with respect to all the material expanding away from it.Of course finding that point from our perspective location is impossible but that does not mean the original point does not exist.
That point does still exist and we can easily identify it. It is any point we care to identify. The expansion of the Big Bang is an expansion of all space, not an expansion from a point. If the universe is finite in extent, then when one leaves one side, one comes in on the other side.
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Sigh... I have to wonder sometimes if people actually read what has already been posted before they post their own ideas.
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Sigh... I have to wonder sometimes if people actually read what has already been posted before they post their own ideas.
That ain't right. It should be "le sigh", or maybe it's "la sigh". Anyway, you know what I mean.
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Speculation is inferior.
Wondering who one's father is, asking each man "Are you my father?", denying that one's existence depends on input of a father or designating a particular person as one's father without proof, are all inferior to accepting the version of one's own mother. [O8)] Remember, Truth Seekers--just because a speculator has a following does not mean he got everything or anything right, it just means other speculators have rubber-stamped him with their approval.
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Sigh... I have to wonder sometimes if people actually read what has already been posted before they post their own ideas.
I feel like that sometimes too. I think most of the time though, there is more to it than meets the eye.
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Speculation is inferior.
Wondering who one's father is, asking each man "Are you my father?", denying that one's existence depends on input of a father or designating a particular person as one's father without proof, are all inferior to accepting the version of one's own mother. [O8)] Remember, Truth Seekers--just because a speculator has a following does not mean he got everything or anything right, it just means other speculators have rubber-stamped him with their approval.
There are educated guesses.
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Phys, let's suppose that after the explosion of radiation from the BB that no matter formed. That radiation is space and space is expanding. This would suggest if we could rewind that radiation in reverse it would go to a particular point with respect to that radiation. We can not say that point is relative to anything outside the expanding sphere but it is relative to the space being created.
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Phys, let's suppose that after the explosion of radiation from the BB that no matter formed. That radiation is space and space is expanding. This would suggest if we could rewind that radiation in reverse it would go to a particular point with respect to that radiation. We can not say that point is relative to anything outside the expanding sphere but it is relative to the space being created.
Except space itself expands uniformly, and so does the matter... or in this case photons... the photons do not expand, it's the spacetime they travel in which expands which mean's that there is no center. Even if you took everything back a few seconds after big bang, you would not be able to (and there is that word again) destinguish where the big bang had occured.
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And you know beyond a shadow of a doubt that the wavelength of light does not get longer as it propagates away from it's source?
You can claim that my premise is flawed and I claim yours to be flawed, an impasse. Mine is based on logic, yours is based on what someone has told you.
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And you know beyond a shadow of a doubt that the wavelength of light does not get longer as it propagates away from it's source?
You can claim that my premise is flawed and I claim yours to be flawed, an impasse. Mine is based on logic, yours is based on what someone has told you.
You might call it logic, but I call it just making stuff up.
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Phys, you didn't respond to the first part of my reply?
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Phys, let's suppose that after the explosion of radiation from the BB that no matter formed. That radiation is space and space is expanding. This would suggest if we could rewind that radiation in reverse it would go to a particular point with respect to that radiation. We can not say that point is relative to anything outside the expanding sphere but it is relative to the space being created.
OK, first there is no explosion of radiation from the Big Bang. There is no Big Bang. There are many theories about what might be the origin of the universe, but none of these has been established to any great degree. The Big Bang theory that scientists actually believe starts from a time when the universe exists in a given state and then tracks the history of the universe from there.
Second, if we track any expansion back, we still cannot find a single point that all the expansion started from. The geometry simply doesn't work like that. (One has to turn to differential geometry to understand this in detail.) As we rewind the clock, we see that the average distance between everything gets smaller. Things do not contract to a point, they just contract.
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Nice one Fozzie.
The analogy is not bad but we have to remember that it is layer on layer on layer as the balloon can be seen as a 'two dimensional' description of a three dimensional reality.
http://math.ucr.edu/home/baez/physics/Relativity/GR/centre.html
Sorry... what? I wonder... if i can actually manage sometimes to try and remain scientific when i have people like yourself coaching on psuedoscientific ideologies. Now don't get me wrong, i love to think outside the box, but i pointed out that he or she was wrong. I don't need yourself to say erreneous things like ''nice one fozzie'' - when there was nothing correct about the proposal. By doing this, you are intentionally-misleading people.
Did you check the link. Whatever 'unscientificity' you found you can take up with Philip Gibbs. I'm sure you can teach him how to really understand physics mr. S.
Until then
Cheers.
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Ok phys, I think I understand your position. If the Universe had no beginning your position is correct. Sounds like you believe in a steady state? A few days ago I had a really weird thought that would allow for a multiverse situation. I'll type up the post in the next couple of days.
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Ok phys, I think I understand your position. If the Universe had no beginning your position is correct. Sounds like you believe in a steady state? A few days ago I had a really weird thought that would allow for a multiverse situation. I'll type up the post in the next couple of days.
I don't believe in the steady state theory. I believe in the Big Bang theory. The Big bang theory does not actually include a big bang.