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Old 06-19-2012, 12:51 AM
 
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Quote:
Originally Posted by Brian.Pearson View Post
I was thinking about the Penrose rings you mentioned. Of course, you may have already thought of it.
I still have no idea where those rings are suppose to be located in the CMB. Do you?
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Old 06-19-2012, 01:19 AM
 
Location: Wasilla, Alaska
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Quote:
Originally Posted by NightBazaar View Post
I still have no idea where those rings are suppose to be located in the CMB. Do you?
Here is something interesting. The NYT article on the same subject, mentioning Roger Penrose of Oxford University and Vahe Gurzadyan of Yerevan State University in Armenia, has a completely different image from the article you posted.

Rings in Sky Leave Alternate Visions of Universes

I fail to see how arbitrarily drawing concentric rings on the CMB demonstrates anything.

This smacks of someone desperately attempting to validate M-theory. Where they envision multiple dimensions, shaped like membranes or sheets. They theorize that the "Big Bang" is the result of a collision between two of those membranes. In which case, such a contact between membranes would leave a ripple effect at the point of contact, which might show up in the CMB. It should also be detectable in the form of gravity waves.

I am not going to make any judgements, either way. We just are not quite there yet to be able to give a definitive "Yes" or "No." I know they have plans to build gravity wave detectors, maybe they will be able to prove M-theory. Although, if no gravity waves are detected, that does not necessarily mean they are not out there. I do not know who said it, but "the absence of evidence is not evidence of absence."

Last edited by Glitch; 06-19-2012 at 01:32 AM..
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Old 06-19-2012, 12:37 PM
 
5,203 posts, read 8,205,785 times
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Quote:
Originally Posted by Glitch View Post
Here is something interesting. The NYT article on the same subject, mentioning Roger Penrose of Oxford University and Vahe Gurzadyan of Yerevan State University in Armenia, has a completely different image from the article you posted.

Rings in Sky Leave Alternate Visions of Universes

I fail to see how arbitrarily drawing concentric rings on the CMB demonstrates anything.
The link above leads to a "Page Not Found". Admittedly, the link I posted isn't the greatest. Does this Nat Geo article show the same image that you mentioned in the NY Times article?
Space Circles Are Proof of a Pre-Big Bang Universe?

The subject of Penrose's 'rings' is one that was discussed in a thread here. It's pretty brief.
Evidence of Pre-BigBang events?


Quote:
This smacks of someone desperately attempting to validate M-theory. Where they envision multiple dimensions, shaped like membranes or sheets. They theorize that the "Big Bang" is the result of a collision between two of those membranes. In which case, such a contact between membranes would leave a ripple effect at the point of contact, which might show up in the CMB. It should also be detectable in the form of gravity waves.
Penrose's view suggests a cyclic universe involving a singularity and multiple Big Bangs. On the other hand, Neil Turok and Paul Steinhardt developed the ekpyrotic model that doesn't require a singularity but could have involved two branes that ripple and collide, the collision generating enough energy to form an entire universe. This model also has the potential of 'sparking' lots of universe-sized structures, some that work and some that may fail. It's been hoped that the Planck spacecraft should be able to detect the faint, ancient gravity waves leftover from the Big Bang, but as far as I know, there's been no detection yet. So we're still left with not knowing if the Big Bang had a first cause or no cause at all. The LISA mission, if launched, is another that shoulld be able to measure gravitational waves. The US pulled out of that project, so it's uncertain how much of a delay that will mean.
Cyclic model - Wikipedia, the free encyclopedia

Ekpyrotic universe - Wikipedia, the free encyclopedia

[hep-th/0103239] The Ekpyrotic Universe: Colliding Branes and the Origin of the Hot Big Bang



Roger Penrose - Cyclic Universe Model - YouTube




Quote:
I am not going to make any judgements, either way. We just are not quite there yet to be able to give a definitive "Yes" or "No." I know they have plans to build gravity wave detectors, maybe they will be able to prove M-theory. Although, if no gravity waves are detected, that does not necessarily mean they are not out there. I do not know who said it, but "the absence of evidence is not evidence of absence."
I agree that we have to keep an open mind, and you're quite right that there are no definitive answers. But it's very interesting and important to explore different scenarios with the idea that one of them may turn out to be on the right trail. Or it may be something we'll never have a satisfactory answer to. I think it's always worth discussion in that it helps broaden our own views and knowledge. We all have our 'favorites'. I'm no exception, but I'm open to adapt to changes as new information is discovered.
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Old 06-19-2012, 01:19 PM
 
Location: Wasilla, Alaska
17,825 posts, read 20,496,555 times
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Quote:
Originally Posted by NightBazaar View Post
The link above leads to a "Page Not Found".
Oops! I must have screwed up the link. Sorry about that.

http://www.nytimes.com/2010/12/14/sc...smic.html?_r=1

Quote:
Originally Posted by NightBazaar View Post
Admittedly, the link I posted isn't the greatest. Does this Nat Geo article show the same image that you mentioned in the NY Times article?
Space Circles Are Proof of a Pre-Big Bang Universe?
No, different image altogether. I like that image, it at least gives us someplace to look on the CMB image.

Quote:
Originally Posted by NightBazaar View Post
The subject of Penrose's 'rings' is one that was discussed in a thread here. It's pretty brief.
Evidence of Pre-BigBang events?



Penrose's view suggests a cyclic universe involving a singularity and multiple Big Bangs. On the other hand, Neil Turok and Paul Steinhardt developed the ekpyrotic model that doesn't require a singularity but could have involved two branes that ripple and collide, the collision generating enough energy to form an entire universe. This model also has the potential of 'sparking' lots of universe-sized structures, some that work and some that may fail. It's been hoped that the Planck spacecraft should be able to detect the faint, ancient gravity waves leftover from the Big Bang, but as far as I know, there's been no detection yet. So we're still left with not knowing if the Big Bang had a first cause or no cause at all. The LISA mission, if launched, is another that shoulld be able to measure gravitational waves. The US pulled out of that project, so it's uncertain how much of a delay that will mean.
Cyclic model - Wikipedia, the free encyclopedia

Ekpyrotic universe - Wikipedia, the free encyclopedia

[hep-th/0103239] The Ekpyrotic Universe: Colliding Branes and the Origin of the Hot Big Bang


Roger Penrose - Cyclic Universe Model - YouTube

I agree that we have to keep an open mind, and you're quite right that there are no definitive answers. But it's very interesting and important to explore different scenarios with the idea that one of them may turn out to be on the right trail. Or it may be something we'll never have a satisfactory answer to. I think it's always worth discussion in that it helps broaden our own views and knowledge. We all have our 'favorites'. I'm no exception, but I'm open to adapt to changes as new information is discovered.
I am open to being mistaken, and adapting to new concepts, but I need evidence. It does not even need to be definitively evidence. I can also accept that I might be wrong if there are other plausible possibilities.

Before a few weeks ago I was certain that the only form of black holes were stellar in nature. When you explained primordial black holes, I found that they could indeed exist at the very early beginnings after the Big Bang, therefore I can accept that I might be wrong about the origin of black holes. It does not matter that we have not found a primordial black hole, the possibility exists that they could have formed before stars existed, and that is enough for me.

I am not saying that M-theory (which is where the "two branes that ripple and collide" comes from) is nonsense, but I need more evidence. I do not dismiss any theory out-of-hand. I need some evidence that either proves or disproves the theory. So far all we have are mathematical models. Those models say that a collision between the two membranes will cause gravitational waves. However, the Big Bang itself, whether caused by a collision of two membranes or by something else, should also create detectable gravitational waves. So even if we do eventually detect gravitational waves, it will not conclusively prove M-theory, but it will not rule it out either.
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Old 06-19-2012, 04:33 PM
 
5,203 posts, read 8,205,785 times
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Quote:
Originally Posted by Glitch View Post
Oops! I must have screwed up the link. Sorry about that.

http://www.nytimes.com/2010/12/14/sc...smic.html?_r=1



No, different image altogether. I like that image, it at least gives us someplace to look on the CMB image.
Thanks for link correction. That's the image that was associated with the rings in the CMB that Penrose was talking about in regard to a cyclic universe. His view is that the universe expands indefinitely to where it reaches a point of near nothingness, which the triggers a new Big Bang and potentially a new universe which may or may not be like the one we occupy. His speculation is that the rings may be evidence that the universe undergoes multiple Big Bangs. I still have no idea where these rings are to be found in the CMB. Further, to me, all it looks like are transparent graphical rings overlaid on a picture of the CMB. That's fine, but I can't see anything at all that even remotely resembles concentric rings. I'm sure he has a reason for his thinking, but it's beyond me as to what it is.


Quote:
I am open to being mistaken, and adapting to new concepts, but I need evidence. It does not even need to be definitively evidence. I can also accept that I might be wrong if there are other plausible possibilities.

Before a few weeks ago I was certain that the only form of black holes were stellar in nature. When you explained primordial black holes, I found that they could indeed exist at the very early beginnings after the Big Bang, therefore I can accept that I might be wrong about the origin of black holes. It does not matter that we have not found a primordial black hole, the possibility exists that they could have formed before stars existed, and that is enough for me.
We all make errors. It's part of the process of learning new things which keeps it all interesting. I make more mistakes than you can shake a stick at, to the point that I think I should probably shut up. There's more that I don't know than I'll ever hope to know. I'll have to leave that for future generations to try to figure out. But I also realize that we learn about things that interest us by interacting and exchanging thoughts with others. I'd never learn anything if it wasn't for communicating with people like you and others.


Quote:
I am not saying that M-theory (which is where the "two branes that ripple and collide" comes from) is nonsense, but I need more evidence. I do not dismiss any theory out-of-hand. I need some evidence that either proves or disproves the theory. So far all we have are mathematical models. Those models say that a collision between the two membranes will cause gravitational waves. However, the Big Bang itself, whether caused by a collision of two membranes or by something else, should also create detectable gravitational waves. So even if we do eventually detect gravitational waves, it will not conclusively prove M-theory, but it will not rule it out either.
I know you weren't saying that M-theory is nonsense. LOL! I was just expanding on my own rambling thoughts about the variety of different theories there are pertaining to the question of the origin of the universe. I agree that it all boils down to mathematical models. In some of the really BIG questions, it's possible that's we'll never get beyond that without any evidence. But it's hard to say. There are lots of things we may likely have direct knowledge to, but there are some things that are possible we could discover indirect evidence to support things. For example, there may be extra spatial dimensions we'll never be able to observe or measure directly, but we might find indirect evidence using tools like the LHC (maybe) through the collision of particles that could potentially hint at the existence of an extra dimension, and maybe a clue that there's more than just the universe. On the other hand, we'll be doing quite well just to confirm the Higgs boson. It's remarkable the things that continue to be discovered.
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Old 07-08-2012, 10:12 PM
 
Location: On the "Left Coast", somewhere in "the Land of Fruits & Nuts"
8,367 posts, read 8,716,687 times
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Quote:
Originally Posted by Glitch View Post
I am not saying that M-theory (which is where the "two branes that ripple and collide" comes from) is nonsense, but I need more evidence. I do not dismiss any theory out-of-hand. I need some evidence that either proves or disproves the theory. So far all we have are mathematical models. Those models say that a collision between the two membranes will cause gravitational waves. However, the Big Bang itself, whether caused by a collision of two membranes or by something else, should also create detectable gravitational waves. So even if we do eventually detect gravitational waves, it will not conclusively prove M-theory, but it will not rule it out either.
Am probably not as hip to the rest of this as y'all seem to be, but just personally, I especially have a hard time accepting something like M-theory, that just happens to explain away all quantum inconsistencies, by basically saying that anything's possible, just because it's probably happening somewhere else in another universe or dimension! Oh, and even more convenient, the theory is also essentially unprovable (...LOL)!
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Old 07-10-2012, 09:46 PM
 
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Quote:
Originally Posted by mateo45 View Post
Am probably not as hip to the rest of this as y'all seem to be, but just personally, I especially have a hard time accepting something like M-theory, that just happens to explain away all quantum inconsistencies, by basically saying that anything's possible, just because it's probably happening somewhere else in another universe or dimension! Oh, and even more convenient, the theory is also essentially unprovable (...LOL)!
M-theory is hard to wrap your Brane around.
(That'd make a great bumper sticker.)

I don't think it gets down to accepting it, but more in terms of considering it as a potential alternative. I'd be interested knowing in what way M-theory explains away all quantum inconsistencies. Would you mind providing some studies or references about that? What I have a hard time with are Penrose's 'rings' suggesting multiple Big Bangs, that our universe goes through cycles of expansion and contraction. I just don't see what he's talking about in the CMB images. Nor do I see th 'bumps' in the more recent images of multiple collisions (possibly by other universes) said to have occurred early on when our universe was quite young. I don't see it as convincing evidence, but then that's because I don't see what it is they're looking at.

But as for the idea that there might be other universes and other dimensions, it depends on what would be constituted as 'provable'. While I don't think we'll ever have any direct evidence, it is very possible to have indirect evidence. For example, it's hoped that the LHC might be able to detect, or at least infer, extra dimensions which are too small and unseen any other way. As I understand the idea behind such detection has to do with the particles released during a collision. If a particle suddenly disappears, it might be possible it has slipped into a hidden spatial dimension.

The thing to be aware of about dimensions, is that they are not necessarily distinct places of existence. For example, we talk about the space of the universe in terms of being 3-dimensional, and often describe them as length, width and depth as if separate componants. However, they aren't separate at all. They're all connected. That said, it's entirely possible the universe might have four or more spatial dimensions, all tightly integrated together, rather than just three. The way we're made though limits us to three dimensions, so it's not like anyone is going to jump into, or see a 4-dimensional configuration, even if it turns out that we're composed of 4 spatial dimensions. I think the best that could be hoped for is simply knowing whether or not there are any hidden dimensions.

Jumping back to M-theory, and a multiverse scenario, if there are any other universe-sized structures beyond our own universe, we'll never directly see them. They'd be too far for the light to ever reach us, and the accelerated expansion of space guarantees that will never happen. But it is possible that some anomolies may indicate that other universes are possible. While you mentioned the idea of other things happening here may be happening in some other universe, is not necessarily the case. Conditions and physics could more likely be very different than our universe. You couldn't live there. But that's not to say there couldn't be another universe like ours. It would depend on a very large nuber of other universes, perhas an infinite number of universes, out of which some would not only be similar to ours, but could be identicsl to ours. However, we don't know if there are any other universes other than the one we live it. While there are a number of very imaginative and plausible scenarios, we don't really understand exctly why our universe even emerged to exist as it does.

Having said all that, what scenario do you think explains the universe, and in particular the Big Bang? Why did the Big Bang bang? Did it emerge out of nothing? Could it have emerged from a collision of branes? Could it be holographic? How about fractal? I'd be interested in hearing your opinions. There are numerous explanations, but we don't know which one, if any, is the correct Ultimate Theory of Everything. We're still pretty much stuck in this universe.
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