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Time dilation #2
On Apr 9, 10:33*pm, Tom Roberts wrote in
sci.physics.relativity: bill wrote: A person is located on a mountain top and is looking at a (very large) clock (B) at sea-level. He notices that clock B is ticking over at a slower rate than his own clock (A) as theorized by Einstein in general theory and as ratified by the Wallops Island experiment where a clock at sea-level, being located in a strong gravitational tidal area, will tick over at a slower rate than an identical clock on top of a mountain that is in a weaker gravitational tidal area. Note that what you call "gravitational tidal area" is really called "Newtonian gravitational potential", valid in the Newtonian approximation to GR. Indeed, tidal forces/effects are not involved (tidal forces are second derivatives of the Newtonian potential). Note that while A _SEES_ B tick at a slower rate, this does not imply that clock B actually ticks at a slower rate than clock A. Indeed, in GR this is modeled as an artifact of the COMPARISON [#], not as an effect or modification of the clocks themselves: both clocks tick at their usual (proper) rates, but their tick rates appear different when situated and compared as you describe. * * * * [#] This comparison is via EM signals in curved spacetime.. Is he entitled to be of the opinion that if he were to move to sea- level his clock would be subjected to the same 'law' of physics thus it will then be ticking over at a slower rate than it is before he starts his descent? No. See above -- this is not an effect ON THE CLOCKS, but rather OF THE COMPARISON. Note that he is entitled to expect that if he carries his clock down and puts it right next to B that the two clocks will tick at the same rate. Your statements are expressed with the implicit assumption there there is some "global", "universal", or "absolute" way to determine a clock's tick rate. In GR there is no such thing -- all you can do is compare clocks to other clocks; the method of comparison can, and usually does, affect the result. Tom Roberts Honest Roberts, your cleverer brothers Einsteinians expose the "artifact of the COMPARISON" in a somewhat clearer way: http://www.people.fas.harvard.edu/~djmorin/book.html Chapter 14: "The equivalence principle has a striking consequence concerning the behavior of clocks in a gravitational field. It implies that higher clocks run faster than lower clocks. If you put a watch on top of a tower, and then stand on the ground, you will see the watch on the tower tick faster than an identical watch on your wrist. When you take the watch down and compare it to the one on your wrist, it will show more time elapsed." However, Honest Roberts, even your cleverer brothers Einsteinians would never answer the following question: Is the "artifact of the COMPARISON" (that is, gravitational time dilation) consistent with Einsteiniana's dicovery that the speed of light is CONSTANT in a gravitational field, or is it consistent with Einsteiniana's discovery that the speed of light is VARIABLE in a gravitational field and obeys e.g. Einstein's 1911 equation c'=c(1+gh/ c^2) given by Newton's emission theory of light? Pentcho Valev |
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Time dilation #2
On Apr 9, 11:26 pm, Pentcho Valev wrote:
c'=c(1+gh/c^2) given by Newton's emission theory of light? The old fart Pentcho is back jacking off to his old idiocy. |
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Time dilation #2
"Pentcho Valev" wrote in message ... On Apr 9, 10:33 pm, Tom Roberts wrote in sci.physics.relativity: bill wrote: A person is located on a mountain top and is looking at a (very large) clock (B) at sea-level. He notices that clock B is ticking over at a slower rate than his own clock (A) as theorized by Einstein in general theory and as ratified by the Wallops Island experiment where a clock at sea-level, being located in a strong gravitational tidal area, will tick over at a slower rate than an identical clock on top of a mountain that is in a weaker gravitational tidal area. Note that what you call "gravitational tidal area" is really called "Newtonian gravitational potential", valid in the Newtonian approximation to GR. Indeed, tidal forces/effects are not involved (tidal forces are second derivatives of the Newtonian potential). Note that while A _SEES_ B tick at a slower rate, this does not imply that clock B actually ticks at a slower rate than clock A. Indeed, in GR this is modeled as an artifact of the COMPARISON [#], not as an effect or modification of the clocks themselves: both clocks tick at their usual (proper) rates, but their tick rates appear different when situated and compared as you describe. [#] This comparison is via EM signals in curved spacetime. Is he entitled to be of the opinion that if he were to move to sea- level his clock would be subjected to the same 'law' of physics thus it will then be ticking over at a slower rate than it is before he starts his descent? No. See above -- this is not an effect ON THE CLOCKS, but rather OF THE COMPARISON. Note that he is entitled to expect that if he carries his clock down and puts it right next to B that the two clocks will tick at the same rate. Your statements are expressed with the implicit assumption there there is some "global", "universal", or "absolute" way to determine a clock's tick rate. In GR there is no such thing -- all you can do is compare clocks to other clocks; the method of comparison can, and usually does, affect the result. Tom Roberts : Honest Roberts, your cleverer brothers Einsteinians expose the : "artifact of the COMPARISON" in a somewhat clearer way: : http://www.people.fas.harvard.edu/~djmorin/book.html : Chapter 14: "The equivalence principle has a striking consequence : concerning the behavior of clocks in a gravitational field. It implies : that higher clocks run faster than lower clocks. If you put a watch on : top of a tower, and then stand on the ground, you will see the watch : on the tower tick faster than an identical watch on your wrist. When : you take the watch down and compare it to the one on your wrist, it : will show more time elapsed." : However, Honest Roberts, even your cleverer brothers Einsteinians : would never answer the following question: : Is the "artifact of the COMPARISON" (that is, gravitational time : dilation) consistent with Einsteiniana's dicovery that the speed of : light is CONSTANT in a gravitational field, Both are nonsense. Einstein's discovery was just the contrary in both cases: 1. "Thus the clock goes more slowly if set up in the neighbourhood of ponderable masses. From this it follows that the spectral lines of light reaching us from the surface of large stars must appear displaced towards the red end of the spectrum." - http://www.alberteinstein.info/galle..._pp146-200.pdf (p.198) 2. "according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity and to which we have already frequently referred, cannot claim any unlimited validity" - http://www.bartleby.com/173/22.html - see also the same p.198 of the first ref. for details. : or is it consistent with : Einsteiniana's discovery that the speed of light is VARIABLE in a : gravitational field and obeys e.g. Einstein's 1911 equation c'=c(1+gh/ : c^2) given by Newton's emission theory of light? You should instead refer to his corrected equations of 1916 - which are NOT given by Newton's theory. Good luck. Harald |
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Time dilation #2
On Apr 10, 12:48*pm, "harry"
wrote: "Pentcho Valev" wrote: : or is it consistent with : Einsteiniana's discovery that the speed of light is VARIABLE in a : gravitational field and obeys e.g. Einstein's 1911 equation c'=c(1+gh/ : c^2) given by Newton's emission theory of light? You should instead refer to his corrected equations of 1916 - which are NOT given by Newton's theory. In 1915 Einstein replaced c'=c(1+gh/c^2) with c'=c(1+2gh/c^2): http://www.mathpages.com/rr/s6-01/6-01.htm "In geometrical units we define c_0 = 1, so Einstein's 1911 formula can be written simply as c=1+phi. However, this formula for the speed of light (not to mention this whole approach to gravity) turned out to be incorrect, as Einstein realized during the years leading up to 1915 and the completion of the general theory. In fact, the general theory of relativity doesn't give any equation for the speed of light at a particular location, because the effect of gravity cannot be represented by a simple scalar field of c values. Instead, the "speed of light" at a each point depends on the direction of the light ray through that point, as well as on the choice of coordinate systems, so we can't generally talk about the value of c at a given point in a non- vanishing gravitational field. However, if we consider just radial light rays near a spherically symmetrical (and non- rotating) mass, and if we agree to use a specific set of coordinates, namely those in which the metric coefficients are independent of t, then we can read a formula analogous to Einstein's 1911 formula directly from the Schwarzschild metric. (...) In the Newtonian limit the classical gravitational potential at a distance r from mass m is phi=-m/r, so if we let c_r = dr/dt denote the radial speed of light in Schwarzschild coordinates, we have c_r =1+2phi, which corresponds to Einstein's 1911 equation, except that we have a factor of 2 instead of 1 on the potential term." However the new equation, c'=c(1+2gh/c^2), was incompatible with the gravitational redshift factor experimentally confirmed by Pound and Rebka: http://www.blazelabs.com/f-g-gcont.asp "So, faced with this evidence most readers must be wondering why we learn about the importance of the constancy of speed of light. Did Einstein miss this? Sometimes I find out that what's written in our textbooks is just a biased version taken from the original work, so after searching within the original text of the theory of GR by Einstein, I found this quote: "In the second place our result shows that, according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity and to which we have already frequently referred, cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity of propagation of light varies with position. Now we might think that as a consequence of this, the special theory of relativity and with it the whole theory of relativity would be laid in the dust. But in reality this is not the case. We can only conclude that the special theory of relativity cannot claim an unlimited domain of validity ; its results hold only so long as we are able to disregard the influences of gravitational fields on the phenomena (e.g. of light)." - Albert Einstein (1879-1955) - The General Theory of Relativity: Chapter 22 - A Few Inferences from the General Principle of Relativity-. Today we find that since the Special Theory of Relativity unfortunately became part of the so called mainstream science, it is considered a sacrilege to even suggest that the speed of light be anything other than a constant. This is somewhat surprising since even Einstein himself suggested in a paper "On the Influence of Gravitation on the Propagation of Light," Annalen der Physik, 35, 1911, that the speed of light might vary with the gravitational potential. Indeed, the variation of the speed of light in a vacuum or space is explicitly shown in Einstein's calculation for the angle at which light should bend upon the influence of gravity. One can find his calculation in his paper. The result is c'=c(1+V/c^2) where V is the gravitational potential relative to the point where the measurement is taken. 1+V/c^2 is also known as the GRAVITATIONAL REDSHIFT FACTOR." Pentcho Valev |
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Time dilation #2
"Pentcho Valev" wrote in message ... On Apr 10, 12:48 pm, "harry" wrote: "Pentcho Valev" wrote: : or is it consistent with : Einsteiniana's discovery that the speed of light is VARIABLE in a : gravitational field and obeys e.g. Einstein's 1911 equation c'=c(1+gh/ : c^2) given by Newton's emission theory of light? You should instead refer to his corrected equations of 1916 - which are NOT given by Newton's theory. : In 1915 Einstein replaced c'=c(1+gh/c^2) with c'=c(1+2gh/c^2): : http://www.mathpages.com/rr/s6-01/6-01.htm [...] In view of what you write below, you certainly did not understand the explanation of mathpages that light speed is a function of direction and in this case *perpendicular* to the star. But even that is irrelevant for your problem. : However the new equation, c'=c(1+2gh/c^2), was incompatible with the : gravitational redshift factor experimentally confirmed by Pound and : Rebka: [..] : "The result is c'=c(1+V/c^2) : where V is the gravitational potential relative to the point where the : measurement is taken. 1+V/c^2 is also known as the GRAVITATIONAL : REDSHIFT FACTOR." By chance I already cited the redshift prediction here above (in the part you snipped). You failed to notice that gravitational redshift is only due to the difference in resonance frequencies - neither of which depends on the speed of light between the point of emission and the point of reception. And I explained this too many times to you already. Good luck - you need it. Harald |
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Time dilation #2
"harry" wrote in message ... "Pentcho Valev" wrote in message ... On Apr 10, 12:48 pm, "harry" wrote: "Pentcho Valev" wrote: : or is it consistent with : Einsteiniana's discovery that the speed of light is VARIABLE in a : gravitational field and obeys e.g. Einstein's 1911 equation c'=c(1+gh/ : c^2) given by Newton's emission theory of light? You should instead refer to his corrected equations of 1916 - which are NOT given by Newton's theory. : In 1915 Einstein replaced c'=c(1+gh/c^2) with c'=c(1+2gh/c^2): : http://www.mathpages.com/rr/s6-01/6-01.htm [...] In view of what you write below, you certainly did not understand the explanation of mathpages that light speed is a function of direction and in this case *perpendicular* to the star. But even that is irrelevant for your problem. : However the new equation, c'=c(1+2gh/c^2), was incompatible with the : gravitational redshift factor experimentally confirmed by Pound and : Rebka: [..] : "The result is c'=c(1+V/c^2) : where V is the gravitational potential relative to the point where the : measurement is taken. 1+V/c^2 is also known as the GRAVITATIONAL : REDSHIFT FACTOR." By chance I already cited the redshift prediction here above (in the part you snipped). You failed to notice that gravitational redshift is only due to the difference in resonance frequencies - neither of which depends on the speed of light between the point of emission and the point of reception. And I explained this too many times to you already. Good luck - you need it. Harald However, there is more to it! Although Pentcho misdirected his attack, the above equation of mathpages does appear to be erroneous. Reminder, mathpages: "we have c_r =1+2phi, which corresponds to Einstein's 1911 equation, except that we have a factor of 2 instead of 1 on the potential term." According to Einstein 1916, the tangential length of a measuring rod is *not* affected by gravity. Thus the tangential speed of light should decrease with increasing gravity just as he assumed in 1911, when he only accounted for time dilation and forgot to account for a possible change of length. By way of fast verification, when comparing the equations in his 1916 paper I do find the same factor 8*pi*r for tangential speed of light as well as time dilation, which is consistent (locally the value c must be found). Apparently the different light bending prediction of 1916 was due to an important detail of the calculation (which I never reproduced), and not due to a change in the light speed equation as sometimes suggested in the literature. As a matter of fact, the information about this topic in the literature is both scarce and confused. I would welcome constructive clarifications about Einstein's 1916 paper (p.197-198) from people who studied Einstein's GRT. As a reminder, you can get it he http://www.alberteinstein.info/galle..._pp146-200.pdf Harald |
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Time dilation #2
On Apr 10, 12:26*am, Pentcho Valev wrote:
On Apr 9, 10:33*pm, Tom Roberts wrote in sci.physics.relativity: bill wrote: A person is located on a mountain top and is looking at a (very large) clock (B) at sea-level. He notices that clock B is ticking over at a slower rate than his own clock (A) as theorized by Einstein in general theory and as ratified by the Wallops Island experiment where a clock at sea-level, being located in a strong gravitational tidal area, will tick over at a slower rate than an identical clock on top of a mountain that is in a weaker gravitational tidal area. Note that what you call "gravitational tidal area" is really called "Newtonian gravitational potential", valid in the Newtonian approximation to GR. Indeed, tidal forces/effects are not involved (tidal forces are second derivatives of the Newtonian potential). Note that while A _SEES_ B tick at a slower rate, this does not imply that clock B actually ticks at a slower rate than clock A. Indeed, in GR this is modeled as an artifact of the COMPARISON [#], not as an effect or modification of the clocks themselves: both clocks tick at their usual (proper) rates, but their tick rates appear different when situated and compared as you describe. * * * * [#] This comparison is via EM signals in curved spacetime. Is he entitled to be of the opinion that if he were to move to sea- level his clock would be subjected to the same 'law' of physics thus it will then be ticking over at a slower rate than it is before he starts his descent? No. See above -- this is not an effect ON THE CLOCKS, but rather OF THE COMPARISON. Note that he is entitled to expect that if he carries his clock down and puts it right next to B that the two clocks will tick at the same rate. Your statements are expressed with the implicit assumption there there is some "global", "universal", or "absolute" way to determine a clock's tick rate. In GR there is no such thing -- all you can do is compare clocks to other clocks; the method of comparison can, and usually does, affect the result. Tom Roberts Honest Roberts, your cleverer brothers Einsteinians expose the "artifact of the COMPARISON" in a somewhat clearer way: http://www.people.fas.harvard.edu/~djmorin/book.html Chapter 14: "The equivalence principle has a striking consequence concerning the behavior of clocks in a gravitational field. It implies that higher clocks run faster than lower clocks. If you put a watch on top of a tower, and then stand on the ground, you will see the watch on the tower tick faster than an identical watch on your wrist. When you take the watch down and compare it to the one on your wrist, it will show more time elapsed." However, Honest Roberts, even your cleverer brothers Einsteinians would never answer the following question: Is the "artifact of the COMPARISON" (that is, gravitational time dilation) consistent with Einsteiniana's dicovery that the speed of light is CONSTANT in a gravitational field, or is it consistent with Einsteiniana's discovery that the speed of light is VARIABLE in a gravitational field and obeys e.g. Einstein's 1911 equation c'=c(1+gh/ c^2) given by Newton's emission theory of light? Pentcho Valev Einstein arrived to Special Relativity. The next is General Relativity. Nobody else can put together the Complete Relativity, nor many want. Many theoretical physicists were looking for the Unified Theory. Three steps. The created Special Inertia for dark matter. It worked. |
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Time dilation #2
*c'=c(1+gh/c^2) given by Newton's emission theory of light?
The old fart Pentcho is back jacking off to his old idiocy. He is darkened by his French side. You by your American side. "He is back Jack. Hey, Jackass!" |
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Time dilation #2
"harry" wrote:
...the above equation of mathpages does appear to be erroneous. Reminder, mathpages: "we have c_r =1+2phi, which corresponds to Einstein's 1911 equation, except that we have a factor of 2 instead of 1 on the potential term." That equation is correct, assuming "c_r" represents the radial speed in Schwarzschild coordinates. What makes you think it isn't correct? Apparently the different light bending prediction of 1916 was due to an important detail of the calculation (which I never reproduced)... The calculation can be found in many good references (including the mathpages you mentioned above), and the source of the doubling of the deflection is clearly shown. ... and not due to a change in the light speed equation as sometimes suggested in the literature. The same fact that causes the speed of light to be different in different directions also results in the factor of 2 in the deflection. Perhaps this is what the literature is suggesting? As a matter of fact, the information about this topic in the literature is both scarce and confused. I know a guy who was married fived times, and says each of his wives was impossible to live with. |
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Time dilation #2
"Henry Sharma" wrote in message ... "harry" wrote: ...the above equation of mathpages does appear to be erroneous. Reminder, mathpages: "we have c_r =1+2phi, which corresponds to Einstein's 1911 equation, except that we have a factor of 2 instead of 1 on the potential term." That equation is correct, assuming "c_r" represents the radial speed in Schwarzschild coordinates. What makes you think it isn't correct? Ai! I forgot that Pencho just cited the radial speed eventhough I noticed it in my earlier posting! Indeed, that's correct, thanks for reminding me. :-) Apparently the different light bending prediction of 1916 was due to an important detail of the calculation (which I never reproduced)... The calculation can be found in many good references (including the mathpages you mentioned above), and the source of the doubling of the deflection is clearly shown. In the meantime I found a more detailed calculation in the GRT textbook by Adler, Bazin and Schiffer. They repeat Einstein's calculation of double bending using the Huygens principle with more detail than Einstein in 1916. ... and not due to a change in the light speed equation as sometimes suggested in the literature. The same fact that causes the speed of light to be different in different directions also results in the factor of 2 in the deflection. Perhaps this is what the literature is suggesting? Perhaps. As a matter of fact, the information about this topic in the literature is both scarce and confused. I know a guy who was married fived times, and says each of his wives was impossible to live with. :-)) Thanks, Harald |
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