|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
WHY LIGHT IS SO OFTEN REDSHIFTED
According to Newton's emission theory of light, light slows down in
the gravitational field of the emitter and continues to move REDSHIFTED in the distant (zero-field) space with a DECREASED speed c'=c(1+phi/c^2), where phi is the gravitational potential difference between the surface of the emitter and the distant (zero-field) space. According to Einstein's relativity, light slows down even more vigorously in the gravitational field of the emitter and continues to move EVEN MORE REDSHIFTED in the distant (zero-field) space with an EVEN LOWER speed c'=c(1+2phi/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." http://www.speed-light.info/speed_of_light_variable.htm "Einstein wrote this paper in 1911 in German (download from: http://www.physik.uni-augsburg.de/an...35_898-908.pdf ). It predated the full formal development of general relativity by about four years. You can find an English translation of this paper in the Dover book 'The Principle of Relativity' beginning on page 99; you will find in section 3 of that paper Einstein's derivation of the variable speed of light in a gravitational potential, eqn (3). The result is: c'=c0(1+phi/c^2) where phi is the gravitational potential relative to the point where the speed of light co is measured......You can find a more sophisticated derivation later by Einstein (1955) from the full theory of general relativity in the weak field approximation....For the 1955 results but not in coordinates see page 93, eqn (6.28): c(r)=[1+2phi(r)/c^2]c. Namely the 1955 approximation shows a variation in km/sec twice as much as first predicted in 1911." Apart from the gravitational redshift, light seems to slow down (and so gets additionally redshifted) even in the absence of a gravitational field, due to "friction" with some unknown components of "empty" space. Naturally, this (Hubble) redshift is proportional to the distance. Einsteinians have found it profitable to explain Hubble redshift not in terms of slowing down of the speed of light but, rather, in terms of an accelerating expansion of the universe. Given the perfect discipline in Einsteiniana, hints at slowing down of the speed of light in empty space never come from Einsteinians. There was one exception (now suppressed): http://www.sciscoop.com/2008/10 "Does the apparently constant speed of light change over the vast stretches of the universe? Would our understanding of black holes, ancient supernovae, dark matter, dark energy, the origins of the universe and its ultimate fate be different if the speed of light were not constant?.....Couldn't it be that the supposed vacuum of space is acting as an interstellar medium to lower the speed of light like some cosmic swimming pool? If so, wouldn't a stick plunged into the pool appear bent as the light is refracted and won't that affect all our observations about the universe. I asked theoretical physicist Leonard Susskind, author of The Black Hole War, recently reviewed in Science Books to explain this apparent anomaly....."You are entirely right," he told me, "there are all sorts of effects on the propagation of light that astronomers and astrophysicists must account for. The point of course is that they (not me) do take these effects into account and correct for them." "In a way this work is very heroic but unheralded," adds Susskind, "An immense amount of extremely brilliant analysis has gone into the detailed corrections that are needed to eliminate these 'spurious' effects so that people like me can just say 'light travels with the speed of light.' So, there you have it. My concern about cosmic swimming pools and bent sticks does indeed apply, but physicists have taken the deviations into account so that other physicists, such as Susskind, who once proved Stephen Hawking wrong, can battle their way to a better understanding of the universe." Pentcho Valev |
#2
|
|||
|
|||
WHY LIGHT IS SO OFTEN REDSHIFTED
Pentcho Valev wrote:
According to Newton's emission theory of light, [snip crap] "Principia," 1687; and already wrong. Pentcho Valev idiot -- Uncle Al http://www.mazepath.com/uncleal/ (Toxic URL! Unsafe for children and most mammals) http://www.mazepath.com/uncleal/qz4.htm |
#3
|
|||
|
|||
WHY LIGHT IS SO OFTEN REDSHIFTED
On Jun 18, 12:44*am, Pentcho Valev wrote:
why light is so often redshifted? why do fireworks spread out of the bangs source!!! |
#4
|
|||
|
|||
WHY LIGHT IS SO OFTEN REDSHIFTED
On Jun 18, 1:09*pm, Raymond Yohros wrote:
On Jun 18, 12:44*am, Pentcho Valev wrote: why light is so often redshifted? why do fireworks spread out of the bangs source!!! Light flowing through space expands with it for billions of light years. There is no prefered scale for inbetween galaxies. Orbits and light expand. This is universal evolution. Mitch Raemsch |
#5
|
|||
|
|||
WHY LIGHT IS SO OFTEN REDSHIFTED
Einsteiniana's explanation of the Doppler effect is even sillier than
the explanations of the gravitational and cosmological redshifts. It implies that, as the observer starts moving towards the wave source, wavecrests start hitting him more frequently not because the speed of the waves relative to him has increased but because the wavelength has miraculously decreased. That is, the wavelength is sensitive to the movements of the observer and changes with his speed so as to satisfy Divine Albert's Divine Theory. You would not find this implication made explicit by Einsteinians except in two texts (one of them was suppressed after I started quoting it too frequently): http://sampit.geol.sc.edu/Doppler.html "Moving observer: A man is standing on the beach, watching the tide. The waves are washing into the shore and over his feet with a constant frequency and wavelength. However, if he begins walking out into the ocean, the waves will begin hitting him more frequently, leading him to perceive that the wavelength of the waves has decreased." http://www.pitt.edu/~jdnorton/teachi...ang/index.html John Norton: "Here's a light wave and an observer. If the observer were to hurry towards the source of the light, the observer would now pass wavecrests more frequently than the resting observer. That would mean that moving observer would find the frequency of the light to have increased (AND CORRESPONDINGLY FOR THE WAVELENGTH - THE DISTANCE BETWEEN CRESTS - TO HAVE DECREASED)." Pentcho Valev wrote: According to Newton's emission theory of light, light slows down in the gravitational field of the emitter and continues to move REDSHIFTED in the distant (zero-field) space with a DECREASED speed c'=c(1+phi/c^2), where phi is the gravitational potential difference between the surface of the emitter and the distant (zero-field) space. According to Einstein's relativity, light slows down even more vigorously in the gravitational field of the emitter and continues to move EVEN MORE REDSHIFTED in the distant (zero-field) space with an EVEN LOWER speed c'=c(1+2phi/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." http://www.speed-light.info/speed_of_light_variable.htm "Einstein wrote this paper in 1911 in German (download from: http://www.physik.uni-augsburg.de/an...35_898-908.pdf ). It predated the full formal development of general relativity by about four years. You can find an English translation of this paper in the Dover book 'The Principle of Relativity' beginning on page 99; you will find in section 3 of that paper Einstein's derivation of the variable speed of light in a gravitational potential, eqn (3). The result is: c'=c0(1+phi/c^2) where phi is the gravitational potential relative to the point where the speed of light co is measured......You can find a more sophisticated derivation later by Einstein (1955) from the full theory of general relativity in the weak field approximation....For the 1955 results but not in coordinates see page 93, eqn (6.28): c(r)=[1+2phi(r)/c^2]c. Namely the 1955 approximation shows a variation in km/sec twice as much as first predicted in 1911." Apart from the gravitational redshift, light seems to slow down (and so gets additionally redshifted) even in the absence of a gravitational field, due to "friction" with some unknown components of "empty" space. Naturally, this (Hubble) redshift is proportional to the distance. Einsteinians have found it profitable to explain Hubble redshift not in terms of slowing down of the speed of light but, rather, in terms of an accelerating expansion of the universe. Given the perfect discipline in Einsteiniana, hints at slowing down of the speed of light in empty space never come from Einsteinians. There was one exception (now suppressed): http://www.sciscoop.com/2008/10 "Does the apparently constant speed of light change over the vast stretches of the universe? Would our understanding of black holes, ancient supernovae, dark matter, dark energy, the origins of the universe and its ultimate fate be different if the speed of light were not constant?.....Couldn't it be that the supposed vacuum of space is acting as an interstellar medium to lower the speed of light like some cosmic swimming pool? If so, wouldn't a stick plunged into the pool appear bent as the light is refracted and won't that affect all our observations about the universe. I asked theoretical physicist Leonard Susskind, author of The Black Hole War, recently reviewed in Science Books to explain this apparent anomaly....."You are entirely right," he told me, "there are all sorts of effects on the propagation of light that astronomers and astrophysicists must account for. The point of course is that they (not me) do take these effects into account and correct for them." "In a way this work is very heroic but unheralded," adds Susskind, "An immense amount of extremely brilliant analysis has gone into the detailed corrections that are needed to eliminate these 'spurious' effects so that people like me can just say 'light travels with the speed of light.' So, there you have it. My concern about cosmic swimming pools and bent sticks does indeed apply, but physicists have taken the deviations into account so that other physicists, such as Susskind, who once proved Stephen Hawking wrong, can battle their way to a better understanding of the universe." Pentcho Valev |
#6
|
|||
|
|||
WHY LIGHT IS SO OFTEN REDSHIFTED
Why is light redshifted in a gravitational field? The journal Nature
explains: http://www.nature.com/news/2010/1006....2010.303.html Natu "Gravity is mercilessly impartial - on Earth, it accelerates light and heavy objects alike with a tug of 9.8 metres per second squared." Yes, the frequency shifts because THE SPEED OF LIGHT SHIFTS, in accordance with the equation c'=c(1+V/c^2) given by Newton's emission theory of light (V is the gravitational potential difference between the point of emission and the point of reception of light). Believers would not understand the importance of Nature's confession but at least they could stop singing "Divine Einstein" and "Yes we all believe in relativity, relativity, relativity", just in case: http://www.haverford.edu/physics/songs/divine.htm No-one's as dee-vine as Albert Einstein Not Maxwell, Curie, or Bohr! He explained the photo-electric effect, And launched quantum physics with his intellect! His fame went glo-bell, he won the Nobel -- He should have been given four! No-one's as dee-vine as Albert Einstein, Professor with brains galore! No-one could outshine Professor Einstein -- Egad, could that guy derive! He gave us special relativity, That's always made him a hero to me! Brownian motion, my true devotion, He mastered back in aught-five! No-one's as dee-vine as Albert Einstein, Professor in overdrive! http://www.youtube.com/watch?v=5PkLLXhONvQ We all believe in relativity, relativity, relativity. Yes we all believe in relativity, 8.033, relativity. Einstein's postulates imply That planes are shorter when they fly. Their clocks are slowed by time dilation And look warped from aberration. We all believe in relativity, relativity, relativity. Yes we all believe in relativity, 8.033, relativity. Pentcho Valev |
#7
|
|||
|
|||
WHY LIGHT IS SO OFTEN REDSHIFTED
http://www.physlink.com/Education/AskExperts/ae13.cfm
"So, it is absolutely true that the speed of light is not constant in a gravitational field [which, by the equivalence principle, applies as well to accelerating (non-inertial) frames of reference]. If this were not so, there would be no bending of light by the gravitational field of stars....Indeed, this is exactly how Einstein did the calculation in: 'On the Influence of Gravitation on the Propagation of Light,' Annalen der Physik, 35, 1911. which predated the full formal development of general relativity by about four years. This paper is widely available in English. You can find a copy beginning on page 99 of the Dover book 'The Principle of Relativity.' You will find in section 3 of that paper, Einstein's derivation of the (variable) speed of light in a gravitational potential, eqn (3). The result is, c' = c0 ( 1 + V / c^2 ) where V is the gravitational potential relative to the point where the speed of light c0 is measured." THEOREM 1: The speed of light obeys the equation c'=c(1+V/c^2) if and only if, in the absence of a gravitational field, it obeys the equation c'=c+v where v is the speed of the emitter relative to the observer. Both equations belong to Newton's emission theory of light and contradict Einstein's 1905 light postulate: http://www.fourmilab.ch/etexts/einstein/specrel/www/ "...light is always propagated in empty space with a definite velocity c which is independent of the state of motion of the emitting body." THEOREM 2 (The Redshift Law): If the assumption that the wavelength of light varies with the speed of the observer is absurd, then the following unversal equation holds: f'/f = c'/c where f' is the shifted frequency of light (at the moment of reception), f is the original frequency (at the moment of emission), c' is the speed of light relative to the observer (at the moment of reception), c is the speed of light relative to the emitter (at the moment of emission). Pentcho Valev wrote: Why is light redshifted in a gravitational field? The journal Nature explains: http://www.nature.com/news/2010/1006....2010.303.html Natu "Gravity is mercilessly impartial - on Earth, it accelerates light and heavy objects alike with a tug of 9.8 metres per second squared." Yes, the frequency shifts because THE SPEED OF LIGHT SHIFTS, in accordance with the equation c'=c(1+V/c^2) given by Newton's emission theory of light (V is the gravitational potential difference between the point of emission and the point of reception of light). Believers would not understand the importance of Nature's confession but at least they could stop singing "Divine Einstein" and "Yes we all believe in relativity, relativity, relativity", just in case: http://www.haverford.edu/physics/songs/divine.htm No-one's as dee-vine as Albert Einstein Not Maxwell, Curie, or Bohr! He explained the photo-electric effect, And launched quantum physics with his intellect! His fame went glo-bell, he won the Nobel -- He should have been given four! No-one's as dee-vine as Albert Einstein, Professor with brains galore! No-one could outshine Professor Einstein -- Egad, could that guy derive! He gave us special relativity, That's always made him a hero to me! Brownian motion, my true devotion, He mastered back in aught-five! No-one's as dee-vine as Albert Einstein, Professor in overdrive! http://www.youtube.com/watch?v=5PkLLXhONvQ We all believe in relativity, relativity, relativity. Yes we all believe in relativity, 8.033, relativity. Einstein's postulates imply That planes are shorter when they fly. Their clocks are slowed by time dilation And look warped from aberration. We all believe in relativity, relativity, relativity. Yes we all believe in relativity, 8.033, relativity. Pentcho Valev |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Eavesdropping on Radio Broadcasts from Galactic Civilizations with Upcoming Observatories for Redshifted 21cm Radiation | Joseph Lazio | SETI | 7 | October 24th 06 12:39 PM |
How to make a light-tight red-light sign box for star parties | canopus56 | Amateur Astronomy | 3 | June 5th 06 08:08 PM |