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I was watching a program which were comparing various Big Bang theories
against each other. In it, they said one way to falsify Inflation vs. Cyclic Universe theories is that a Cyclic Universe will *not* produce gravity waves. Does anybody know why this would be the case? One would think that whatever mechanism lead to the BB, would always cause a lot of gravity ripples. I found some info on it, but it doesn't really explain what leads to this conclusion: The one possible test that they point to that could distinguish the inflation and cyclic scenarios is the expected more sensitive measurement in coming years of a possible B-mode polarization signal due to gravity waves in the CMB. They claim that inflation predicts a significant amount of B-mode polarization, whereas the cyclic model doesn’t. Endless Universe | Not Even Wrong http://www.math.columbia.edu/~woit/wordpress/?p=563 Yousuf Khan |
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![]() "Yousuf Khan" wrote: I was watching a program which were comparing various Big Bang theories against each other. In it, they said one way to falsify Inflation vs. Cyclic Universe theories is that a Cyclic Universe will *not* produce gravity waves. Does anybody know why this would be the case? One would think that whatever mechanism lead to the BB, would always cause a lot of gravity ripples. I found some info on it, but it doesn't really explain what leads to this conclusion: The one possible test that they point to that could distinguish the inflation and cyclic scenarios is the expected more sensitive measurement in coming years of a possible B-mode polarization signal due to gravity waves in the CMB. They claim that inflation predicts a significant amount of B-mode polarization, whereas the cyclic model doesn’t. Endless Universe | Not Even Wrong http://www.math.columbia.edu/~woit/wordpress/?p=563 hanson wrote: Yossel, all you did was adding your opinion to the greatest story ever told: "Cosmology".. which is a STORY! Any and all variations are interpretations and educated guesses of what happened yore and yonder. Nowadays all that the public sees are those Photoshopped pictures and artists' renditions. Enjoy all that. It's a vast improvement over religious creationism by the Abrahamic delusions and other tribal, drug induced states. |
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On Apr 12, 5:40 pm, Yousuf Khan wrote:
I was watching a program which were comparing various Big Bang theories against each other. In it, they said one way to falsify Inflation vs. Cyclic Universe theories is that a Cyclic Universe will *not* produce gravity waves. Does anybody know why this would be the case? One would think that whatever mechanism lead to the BB, would always cause a lot of gravity ripples. I found some info on it, but it doesn't really explain what leads to this conclusion: Gravity waves has nothing to do cosmology but the very mathematics of GR that allows a wave equation to be derived similar to the wave equations derived by Maxwell that explained light as electromagnetic radiation. shrug The one possible test that they point to that could distinguish the inflation and cyclic scenarios is the expected more sensitive measurement in coming years of a possible B-mode polarization signal due to gravity waves in the CMB. They claim that inflation predicts a significant amount of B-mode polarization, whereas the cyclic model doesn’t. Cosmology cannot be tested but stated. shrug Endless Universe | Not Even Wrong http://www.math.columbia.edu/~woit/wordpress/?p=563 shrug |
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On Apr 12, 8:40*pm, Yousuf Khan wrote:
I was watching a program which were comparing various Big Bang theories against each other. In it, they said one way to falsify Inflation vs. Cyclic Universe theories is that a Cyclic Universe will *not* produce gravity waves. Does anybody know why this would be the case? One would think that whatever mechanism lead to the BB, would always cause a lot of gravity ripples. I found some info on it, but it doesn't really explain what leads to this conclusion: *The one possible test that they point to that could distinguish the inflation and cyclic scenarios is the expected more sensitive measurement in coming years of a possible B-mode polarization signal due to gravity waves in the CMB. They claim that inflation predicts a significant amount of B-mode polarization, whereas the cyclic model doesn’t. Endless Universe | Not Even Wronghttp://www.math.columbia.edu/~woit/wordpress/?p=563 * * * * Yousuf Khan xxein: Wublee comes close. He explains that the math is similar to EM. But it just doesn't follow that the math is describing a physical wave. EM is just an escape function for energy. It has its longitudinal length appear as a "wave" because the pulse energy is released as building to a peak and then decreasing down until the next pulse. Pictorially as an ocean wave. A so-called 'gravity wave' is different in that it changes the dynamic equlibrium of the temporary state of the present energy in the universe because of the changes of position of the causal mass. And it does not end there. The energy is forced to continuously seek its equilibrium. There is much more to it than that though. No one can comprehend all the complexities that come with it. And then there is that pesky E=mc^2. 'E' as provided by EM radiation? Or E the result of causal change of its position in a temporal equilibrium i.e. just a flow from here to there to seek an equilibrium? Could it be acceptable that the notion we have as a wave has infinitely complex behavior beyond our knowledge? I think we can have both at scale. Whether a sunburn or metabolic change that allows something like a cancer to occur, or the astronomical motions, they all have something in common but are witnessed at different scales of belief that we yet have to unite. The same as considering a gravity wave as a 'wave' without knowing or considering any other explanation. I would welcome any intelligent discussion on this. Just label it "xxein and gravity" for post or email. |
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On Apr 12, 10:04*pm, "hanson" wrote:
"Yousuf Khan" wrote: I was watching a program which were comparing various Big Bang theories against each other. In it, they said one way to falsify Inflation vs. Cyclic Universe theories is that a Cyclic Universe will *not* produce gravity waves. Does anybody know why this would be the case? One would think that whatever mechanism lead to the BB, would always cause a lot of gravity ripples. I found some info on it, but it doesn't really explain what leads to this conclusion: The one possible test that they point to that could distinguish the inflation and cyclic scenarios is the expected more sensitive measurement in coming years of a possible B-mode polarization signal due to gravity waves in the CMB. They claim that inflation predicts a significant amount of B-mode polarization, whereas the cyclic model doesn’t. Endless Universe | Not Even Wrong http://www.math.columbia.edu/~woit/wordpress/?p=563 hanson wrote: Yossel, all you did was adding your opinion to the greatest story ever told: "Cosmology".. which is a STORY! *Any and all variations are interpretations and educated guesses of what happened yore and yonder. Nowadays all that the public sees are those Photoshopped pictures and artists' renditions. Enjoy all that. It's a vast improvement over religious creationism by the Abrahamic delusions and other tribal, drug induced states. ThemTheThey've stated that if one does not learn from Usenet History, then one is condemned to repeat Repeat REPEAT it... how condemnable! Dedicated to all, plus one and +1, the greatest stories ever told... In Mahipal Singh Virdy eloquently writes: "That's a valid point. But physics is not a story. One has to be cognizant of the difference between Reality and the stories within Reality about Reality. Example: Say for the sake of brainstorming, we as humans lost all records of the past. Lost all the books and symbols that the past has impressed upon us. Don't ask how, just assume so. Now, what would happen? It is highly unlikely that the stories of the Religions of the world would be recreated the same as they exist today. The chances are nearly zero. On the otherhand, the laws of physics would be exactly the same when rediscovered. Only the names and faces of the discoverers would change. In this objective sense, physics is not a story. While everything else is. The laws of physics are independent of the cultural and traditional biases, including the religious ones, of any society contemplating this entity called Physics." "How brilliant! This could be called the Law of Conservation of Reason: "Unlike folklore, the laws of physics remain constant under cultural stress." -- Ande Rychter, " Enjo(y)... Cheers... -- Mahipal, pronounced "My Pal" or "Maple"... as in Loops, Syrup, Wood. http://mahipal7638.wordpress.com/meforce/ "If the line between science fiction and science fact doesn't drive you crazy, then you're just not tr(y)ing!" |
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On Apr 13, 2:43 pm, xxein wrote:
On Apr 12, 8:40 pm, Yousuf Khan wrote: I was watching a program which were comparing various Big Bang theories against each other. In it, they said one way to falsify Inflation vs. Cyclic Universe theories is that a Cyclic Universe will *not* produce gravity waves. Does anybody know why this would be the case? One would think that whatever mechanism lead to the BB, would always cause a lot of gravity ripples. I found some info on it, but it doesn't really explain what leads to this conclusion: The one possible test that they point to that could distinguish the inflation and cyclic scenarios is the expected more sensitive measurement in coming years of a possible B-mode polarization signal due to gravity waves in the CMB. They claim that inflation predicts a significant amount of B-mode polarization, whereas the cyclic model doesn’t. Endless Universe | Not Even Wrong http://www.math.columbia.edu/~woit/wordpress/?p=563 xxein: Wublee comes close. He explains that the math is similar to EM. But it just doesn't follow that the math is describing a physical wave. EM is just an escape function for energy. It has its longitudinal length appear as a "wave" because the pulse energy is released as building to a peak and then decreasing down until the next pulse. Pictorially as an ocean wave. Well, it does not matter if you accept Ampere’s assumption in the physical phenomenon of magnetism or not. Nevertheless, magnetism has so very adequately to be able to explain away just about all mundane phenomena observed. It was Maxwell who cleverly showed with definitive mathematical argument that the electric and the magnetic fields are able to propagate away as waves at exactly the speed of light. That was one of mankind’s proudest moments on par with Newton’s gravity thing. shrug A so-called 'gravity wave' is different in that it changes the dynamic equlibrium of the temporary state of the present energy in the universe because of the changes of position of the causal mass. And it does not end there. The energy is forced to continuously seek its equilibrium. Energy is a phenomenon created by an observer. It is ridiculous to tell energy to seek an equilibrium within the harmony of the universe. shrug There is much more to it than that though. No one can comprehend all the complexities that come with it. And then there is that pesky E=mc^2. 'E' as provided by EM radiation? Or E the result of causal change of its position in a temporal equilibrium i.e. just a flow from here to there to seek an equilibrium? Could it be acceptable that the notion we have as a wave has infinitely complex behavior beyond our knowledge? No, waves represent simple phenomena in nature that have been well understood. shrug I think we can have both at scale. Whether a sunburn or metabolic change that allows something like a cancer to occur, or the astronomical motions, they all have something in common but are witnessed at different scales of belief that we yet have to unite. God helps you if you do not believe in Leprechauns or genies. Only these guys can grant you wishes. So, think carefully of your wishes before indulging them since these creatures can be as tricky to deal with as the self-styled physicists. shrug The same as considering a gravity wave as a 'wave' without knowing or considering any other explanation. Gravity waves on based on the assumption if the Riemann curvature tensor is valid. Since the Riemann tensor is created through man- made, tweaked mathematics that offers no connections to the real world, chances are that the Riemann tensor mirrors mere idols in pagan religions. shrug I would welcome any intelligent discussion on this. Just label it "xxein and gravity" for post or email. To carry on any intelligent discussion in physics, you must be proficient in mathematics. Are you? shrug |
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In article ,
Yousuf Khan writes: I was watching a program which were comparing various Big Bang theories against each other. In it, they said one way to falsify Inflation vs. Cyclic Universe theories is that a Cyclic Universe will *not* produce gravity waves. "Gravity waves" and "Gravitational waves" are two very different things, but a little searching says it's the latter that is meant. Sadly, even some otherwise credible web sites seem to get the two mixed up. Does anybody know why this would be the case? There are other sources of gravitational radiation in the early Universe, but those all lead to E-mode polarization. It's specifically the B-mode polarization that is the signature of inflation. There's an overview at http://www.b-pol.org/bpol-science.php and more illustration at http://cosmology.berkeley.edu/~yuki/CMBpol/CMBpol.htm (Read "gravitational waves" where these sites write "gravity waves.) The short answer (as far as I can tell, not being an expert on this subject) is that the origin of the polarization is quantum fluctuations, which are initially tiny but magnified by inflation. Without inflation, there's no such magnification or at least not enough to make the signature observable. If anyone has a clearer (or more accurate!) explanation, I'd love to see it. -- Help keep our newsgroup healthy; please don't feed the trolls. Steve Willner Phone 617-495-7123 Cambridge, MA 02138 USA |
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On 17/04/2013 5:10 PM, Steve Willner wrote:
There are other sources of gravitational radiation in the early Universe, but those all lead to E-mode polarization. It's specifically the B-mode polarization that is the signature of inflation. What do the E- and B-mode polarizations mean anyway? B-mode I'm guessing is the type that is caused by Inflation only, and it's expected to have a wavelength as large as the observable universe. How do you detect a wave that big that you may be sitting right on top of? There's an overview at http://www.b-pol.org/bpol-science.php and more illustration at http://cosmology.berkeley.edu/~yuki/CMBpol/CMBpol.htm (Read "gravitational waves" where these sites write "gravity waves.) Good stuff, I'm reading through the first one, I'll get to the second a bit later. The short answer (as far as I can tell, not being an expert on this subject) is that the origin of the polarization is quantum fluctuations, which are initially tiny but magnified by inflation. Without inflation, there's no such magnification or at least not enough to make the signature observable. If anyone has a clearer (or more accurate!) explanation, I'd love to see it. So far this thread has been occupied mostly by kooks, hopefully somebody in the field can see this and answer? Yousuf Khan |
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On Apr 17, 8:42 pm, Yousuf Khan wrote:
On 17/04/2013 5:10 PM, Steve Willner wrote: There are other sources of gravitational radiation in the early Universe, but those all lead to E-mode polarization. It's specifically the B-mode polarization that is the signature of inflation. What do the E- and B-mode polarizations mean anyway? B-mode I'm guessing is the type that is caused by Inflation only, and it's expected to have a wavelength as large as the observable universe. How do you detect a wave that big that you may be sitting right on top of? If Yousuf has bothered to study GR, he will realize GR has nothing to do with E&M. That means the hypothetical gravity waves, which are the same **** as the gravitational waves, cannot be produced out of E&M. shrug There's an overview at http://www.b-pol.org/bpol-science.php and more illustration at http://cosmology.berkeley.edu/~yuki/CMBpol/CMBpol.htm (Read "gravitational waves" where these sites write "gravity waves.) Good stuff, I'm reading through the first one, I'll get to the second a bit later. Well, tell us what you think of these analyses based on the basic assumptions of current cosmological model turn out. Koobee Wublee couldn’t wait. shrug The short answer (as far as I can tell, not being an expert on this subject) is that the origin of the polarization is quantum fluctuations, which are initially tiny but magnified by inflation. Without inflation, there's no such magnification or at least not enough to make the signature observable. So far this thread has been occupied mostly by kooks, hopefully somebody in the field can see this and answer? Maybe Yousuf can become an expert in cosmology just like everybody else by staring at these two articles since he does not know anything about the mathematics of gravity waves in the first place. Of course, since he knows nothing about the subject, somehow he is very good at spotting kooks who he thinks also know nothing about the subject. Yes, this is a typical the idiot calling another idiot an idiot. The rest is a typical poker game and nothing to do with the discussion of physics. What else is new? shrug |
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In article ,
Yousuf Khan writes: What do the E- and B-mode polarizations mean anyway? They describe the pattern of polarization seen on the sky. One of the references I gave earlier shows examples, and a web search will find others. In principle, either pattern can have any wavelength; the wavelengths and patterns depend on what physical process caused the polarization. So far as we know now, only inflation can create B-mode patterns. -- Help keep our newsgroup healthy; please don't feed the trolls. Steve Willner Phone 617-495-7123 Cambridge, MA 02138 USA |
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