What if the value of c was different

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kg

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>No intrument can ever be built to the degree to overcome chaos and this experiment unfortunately is subject to chaos. I would even go as far to say it is most likely a waste of money. Because the experiment will undoubtedly fail or either fail to produce results significantly more accurate then a lab model. <br />Posted by why06</DIV></p><p>The whole reason for building two such instraments&nbsp;in different parts the country is to&nbsp;help weed out the noise.</p><p>I think the same was said about many new branches of astronomy.&nbsp;&nbsp;Wasn't it thought that there was nothing interesting to be found in the universe at micro wave, radio and x-ray wavelengths?&nbsp; The telescope had been around for years before Galileo pointed it up into the night sky.&nbsp;&nbsp;People at the time thought that there&nbsp;was no particular reason to use&nbsp;a telescope on stars.&nbsp; Anyway, you never know what you will or won't find if you don't look.&nbsp; &nbsp;&nbsp;</p><p><br /><br />&nbsp;</p>
 
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DrRocket

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I rarely think about things all the way through before I post them. Not neccessarily a good trait. I tend to edit after though...&nbsp;Anyway I'm a little confused with this whole interferometer thing. It seems this pulsing of the light could be caused by something much more simple.Ex: The heating of the room. Vibrations in the mirror. An alteration in the light from some of it bouncing off the mirror and the other part going through the glass. It just seems as if there is room for too much experimental error. To calculate the frequency of four different beams of light.&nbsp;&nbsp;However that is not the main reason Im turned off of this idea. It would seem to me that gravity could only be measured in large macroscopic alterations, as the microscopic alterings of spacetime (aka. a rock on the other side of the planet) seem rather insignificant. Not only that, but these differences would be chaotic not the orderly pattern of data these researchers at LIGO and LISA (i think) Are trying to coax out.I'm just not a fan of battling against the butterfly. No intrument can ever be built to the degree to overcome chaos and this experiment unfortunately is subject to chaos. I would even go as far to say it is most likely a waste of money. Because the experiment will undoubtedly fail or either fail to produce results significantly more accurate then a lab model. <br />Posted by why06</DIV></p><p>&nbsp;</p><p>An interferometer does not measure pulsations of light.&nbsp; It measures distance based on the constructive and destructive interference of light waves.&nbsp; This is not a dynamic effect, unless the light sources are themselves moving relative to the interferometer.&nbsp; It is based simply on phase differences in the incoming light waves.</p><p>I don't see anything that that involves chaos in the experiment.&nbsp; Gravity waves are an effect predicted by general relativity.&nbsp; The main issue is that the waves are quite small unless the source is very energetic.&nbsp; That results in a low signal-to-noise ratio, but not chaos.&nbsp; Many approaches have been suggested and tried to&nbsp; obtain the necessary sensitivity and noise rejection.&nbsp; Since the effect that you are looking for is a change in dimension of some body (strain) the attempts revolve around using as large a body as possible plus as sensnitive a method of measuring length as is available (hence the use of light interference patterns) and keeping noise to a minimum (perhaps using cryogenic techniques).&nbsp; </p> <div class="Discussion_UserSignature"> </div>
 
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why06

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<p>&nbsp; </p><p>I have two question:</p><p><strong>What does this mean?</strong> <font color="#0000ff"><em>"This is not a dynamic effect, unless the light sources are themselves moving relative to the interferometer." </em></font></p><p><strong>And I am slightly confused when you use the word "energetic" in this quote.</strong> <font color="#0000ff"><em>"The main issue is that the waves are quite small unless the source is very energetic.&nbsp; That results in a low signal-to-noise ratio, but not chaos."</em></font></p><p>&nbsp;</p><p>Also I would think that this low signal to noise ratio would be the main reason for the chaos, background noise that is. Do you know the hypothesized length of a gravity wave?</p> <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>
 
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DrRocket

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp; I have two question:What does this mean? "This is not a dynamic effect, unless the light sources are themselves moving relative to the interferometer."</DIV></p><p>It means that&nbsp;the inteference patterns&nbsp;do not vary in time.&nbsp; The interference patterns are created by phase differences between&nbsp;two light sources and are constant in time.&nbsp; I was responding to your reference to "pulsing of light", which seeme&nbsp;to me to be indicating a time variation in the intensity of light.&nbsp;</p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>And I am slightly confused when you use the word "energetic" in this quote. "The main issue is that the waves are quite small unless the source is very energetic.&nbsp; That results in a low signal-to-noise ratio, but not chaos."</DIV></p><p>Gravity waves are one means by which energy can be transmitted.&nbsp; The amplitude of the waves reflects the energy contained in them, just as in the case of intensity of light or other electromagnetic waves.&nbsp; The higher the energy and hence amplitude, the greater the likelihood of detection.&nbsp; Signal-to-noise in this case is dependent on the amplitude of the gravity wave signal compared to noise sources, shot noise, thermal noise, etc. that may be present.&nbsp; The higher the amplitude of the gravity wave the higher the signal-to-noise ratio and the more easily the signal can be seen amidst the noise.</p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Also I would think that this low signal to noise ratio would be the main reason for the chaos, background noise that is. Do you know the hypothesized length of a gravity wave? <br />Posted by why06</DIV></p><p>The term "chaos" is often poorly defined but generally refers to a situation in which the behavior of a dynamical system (solution of a system of differential equations, of a system of partial differential equations, behavior of iterations of a function on some topological space, ...) is very sensitive to the assumed initial or boundary conditions.&nbsp; It is quite distinct from issues of stochastic processes or of extraction of signals from noise.&nbsp; Chaos has little to do with the problem of gravity wave detection, though perhaps a "chaotic" dynamical system of very massive bodies could produce rather scrambled gravity waves.</p><p>I don't know the hypothesized length of a gravity wave, but would think it would rather depend on the dynamics of the source emitting the wave.&nbsp; I don't know the anticipated shape either, but again think that would depend on the nature of the source.&nbsp; It is the case that if you know the shape, there are techiques, like matched filters, that can detect a small signal in a large amount of noise.&nbsp; But I don't know what specific methods are being used by the people who actually are designing and conducting the experiments.<br /></p> <div class="Discussion_UserSignature"> </div>
 
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why06

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<p>Good Answer. And thanks</p><p>I was thinking that gravity waves have to transmitted along the median of timespace. At the same time I think of gravity more along the line of the "dimple in the mesh" approach. So the majority of gravity would already be there and the gravitational waves we might detect are really more of a vibration. Sort of like how a bug struggles in a spider's web and the spider can feel the vibrations. Essentially what im saying is that these gravitational waves we detect must be the friction our body (Earth) exhibits against space time itself. We are racecar driving around in the Daytona500. The track being Earth's path around the sun. And the friction with the road being what our tires give off as heat.&nbsp;</p><p>Notice here I'm not saying that interaction with spacetime causes a loss in energy as that would go against Newton 1st law of Motion. Rather I'm saying that the earth is infact trying to continue along its path of motion, that the depression created by the earth is interacting with the depression created by the sun. And where these waves come in contact they form sort of an interference pattern in which the the gravity of each body first cancels each other out and later amplifies each other.</p><p>The study of how to use the additive property of waves in conjunction with gravity waves could lead to incredible leaps in technology such as manmade gravity without the need for centrifugal force.&nbsp; </p> <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>
 
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R1

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<p><font size="2">here's something else, I noticed many of the gravitational waves they intend to measure are from massive orbiting objects.&nbsp; These are probably the strongest waves.&nbsp;</font></p><p><font size="2">However,</font></p><p><font size="2">now I wonder, are we going to specifically measure how fast the strength of gravity is communicated from one mass to another? Or how fast a spacetime ripple of a change in a gravity field can move through a gravity well and space?</font></p><p><font size="2">holy cow, if a black hole the size of a meteor falls in the Atlantic Ocean, how would scientists at MIT measure the speed of gravity? By knowing the distance to the black hole and measuring how long it took from impact to the time the clock feels a horizontal tug?&nbsp; Or by&nbsp;measuring how long it takes for a tsunami to reach MIT? Or are they both the same? And if they're both the same, what if gravity actually travels in a higher dimension?</font></p><p>&nbsp;</p> <div class="Discussion_UserSignature"> </div>
 
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emperor_of_localgroup

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>here's something else, I noticed many of the gravitational waves they intend to measure are from massive orbiting objects.&nbsp; These are probably the strongest waves.&nbsp;However,now I wonder, are we going to specifically measure how fast the strength of gravity is communicated from one mass to another? Or how fast a spacetime ripple of a change in a gravity field can move through a gravity well and space?holy cow, if a black hole the size of a meteor falls in the Atlantic Ocean, how would scientists at MIT measure the speed of gravity? By knowing the distance to the black hole and measuring how long it took from impact to the time the clock feels a horizontal tug?&nbsp; Or by&nbsp;measuring how long it takes for a tsunami to reach MIT? Or are they both the same? And if they're both the same, what if gravity actually travels in a higher dimension?&nbsp; <br />Posted by john1r</DIV><br /><font size="2">I'm a first grader when it comes to gravity wave. But I have to wonder how the heck are they&nbsp; going to measure speed of gravity? Because gravity is unshieldable or can not be shielded by anything, whatsoever.&nbsp;Is this measurement going to be correct?</font></p><p><font size="2">Only thing the scientists should be able to detect are the disturbances in space-time due to vibration of a massive object. This disturbances may be 'wave-like'.&nbsp; But how would you make the earth or the sun to vibrate?</font></p><p><font size="2">Excuse my ignorance.<br /></font></p> <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>
 
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R1

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Replying to:<BR/><DIV CLASS='Discussion_PostQuote'><font color="#000080">I'm a first grader when it comes to gravity wave. But I have to wonder how the heck are they&nbsp; going to measure speed of gravity? Because gravity is unshieldable or can not be shielded by anything, whatsoever.&nbsp;Is this measurement going to be correct?Only thing the scientists should be able to detect are the disturbances in space-time due to vibration of a massive object. This disturbances may be 'wave-like'.&nbsp; But how would you make the earth or the sun to vibrate?Excuse my ignorance.</font> <br />Posted by emperor_of_localgroup</DIV><br /><br /><font size="2">Exactly, and even worse these massive disruption ripples alter time too.&nbsp; And they are already inside a large well to begin with.&nbsp; Similar to what you're talking about, the sun and earth are already in curved spacetime.&nbsp; And even if we could vibrate the sun and the earth, how are we going to get a time measurement (for d/t) to&nbsp;determine the speed, when space and time are alsready out of whack between the sun and the earth, before the experiment even started&nbsp;??</font> <div class="Discussion_UserSignature"> </div>
 
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why06

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Exactly, and even worse these massive disruption ripples alter time too.&nbsp; And they are already inside a large well to begin with.&nbsp; Similar to what you're talking about, the sun and earth are already in curved spacetime.&nbsp; And even if we could vibrate the sun and the earth, how are we going to get a time measurement (for d/t) to&nbsp;determine the speed, when space and time are alsready out of whack between the sun and the earth, before the experiment even started&nbsp;?? <br /> Posted by john1r</DIV></p><p>Well I think they are only detecting small changes huge gravity waves that might occur if our sun was to suddenly pop out of existance. </p><p>As derckmd said, changes in gravitational field that might be due to gravity waves have been applied to real-life problem. </p> <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>
 
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R1

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'><font color="#000080">Well I think they are only detecting small changes huge gravity waves that might occur if our sun was to suddenly pop out of existance. As derckmd said, changes in gravitational field that might be due to gravity waves have been applied to real-life problem. <br /></font>Posted by why06</DIV><br /><br /><font size="2">yes, very well, thanks why06.&nbsp; </font></p><p><font size="2">could&nbsp;various atomic clocks be placed at the distant ends of the interferometers to provide additional data, specifically on time?&nbsp;&nbsp; It seems to me that&nbsp;as the 90 degree laser segments distort,&nbsp;the flow of time should distort as well when the perpendicluar distortion dynamic effects occur.&nbsp;</font></p><p>&nbsp;</p> <div class="Discussion_UserSignature"> </div>
 
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emperor_of_localgroup

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Yes I did say t = c. What does that mean though. Its pointless to define time with a unit of time itself. Since everything is relative from our perspective the only real variable that can be translated across different universes mathematically is "c" itself and that the accelerating expansion of space is infact the decrease of speed "c". Now if c equaled c into other universes and since c is a measurement of space over time then:c = c&nbsp; Then&nbsp; s/t = s/t Therefore if the times are differrent space will compensate to for the variations in time. However since we have a zero dimensional perspective of time s/t = s or we would simply detect a change in space. &nbsp; <br /> Posted by why06</DIV></p><p><font size="2" color="#ff0000">Yes I did say t = c.&nbsp; </font></p><p><font size="2">&nbsp;why06: I had to bring your post back because I had a second thought and now I see a distant possibility of this statement. This is why I read forums, other people's ideas can give another person a new way to explain his/her ideas. Unfortunately, many forum readers spray themselves with "new-idea repellent". </font></p><p><font size="2">I always thought Einstein's relativity had explained the symptoms but hadn't addressed&nbsp; the cause of the symptoms (just like our medical practices.. sorry for the diversion).</font></p><p><font size="2">t=c may be right as speed of time. This explains two things, (1) why speed of light&nbsp; is independent of reference frame; (2) why nothing can travel faster than light. In the second case, if c=t, it means 'breaking the time barrier', which is impossible because 'speed' is 'time dependent' by our current definition of speed.</font></p><p><font size="2">In either case, you need to come up with a new definition of 'time' or 'speed for time'. I have no new idea in that regard. I think this is well ahead of our current scientific thoughts.</font></p><p>&nbsp;</p><p>&nbsp;</p><p><font size="2">&nbsp;</font></p><p><font size="2">&nbsp;</font></p> <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>
 
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