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Topic: light speed is variable

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Le Van Cuong

Hanoi, Vietnam

#1 Nov 18, 2006
I think a light speed is vaviable, this because Einstein forgot a space (km) and a time (s) are based on calculating a unit of velocity (km/s).
Since in Einstein's theory, the moving frame is deemed the inertial frame where light speed is 300,000km/s, then from which frame is measuement taken? Light speed is constant, and therefore equal to the speed in the frame at rest. Thus in Einstein's moving frame where space and time are changed, are such physical factors redundant? If the calculation is made in the moving frame where space and time are changed and in order that such physical factors are mot redundant, then light speed is not 300,000km/s.
we can read this in paper "is Einstein's formula true?", at: http://wbabin.net
Ward Tipton

Quezon, Philippines

#2 Nov 21, 2006
Tests at Princeton (And since repeated elsewhere) showed that light could be accelerated well above the normal and accepted theoretical speed of light. Prisms and other manners of diffusing light have shown that it can be noticably slowed to speeds that the human eye is capable of following. I do not know why the ancient theory of a constant speed of light still exists.
Brandon
#3 Nov 30, 2006
Le Van Cuong wrote:
I think a light speed is vaviable, this because Einstein forgot a space (km) and a time (s) are based on calculating a unit of velocity (km/s).
Since in Einstein's theory, the moving frame is deemed the inertial frame where light speed is 300,000km/s, then from which frame is measuement taken? Light speed is constant, and therefore equal to the speed in the frame at rest. Thus in Einstein's moving frame where space and time are changed, are such physical factors redundant? If the calculation is made in the moving frame where space and time are changed and in order that such physical factors are mot redundant, then light speed is not 300,000km/s.
we can read this in paper "is Einstein's formula true?", at: http://wbabin.net
--It doesn't matter from which frame the measurement is taken. In Einstien's special theory of relativity, it is a fundamental principal that the speed of light is a constant in ALL reference frames, that means, if I could take a ride on a beam of light, I could turn on a flashlight, and the light would still leave my flashlight at the speed of light! This has been proven to hold, check out the info on the Hafele-Keating Experiment on the site "Hyperphysics."--Hap py searching!
Brandon
#4 Nov 30, 2006
Ward Tipton wrote:
Tests at Princeton (And since repeated elsewhere) showed that light could be accelerated well above the normal and accepted theoretical speed of light. Prisms and other manners of diffusing light have shown that it can be noticably slowed to speeds that the human eye is capable of following. I do not know why the ancient theory of a constant speed of light still exists.
--I would like to know which experiments you are referencing, as I am an active physicist, and I do not know of any experiments accelerating light faster than c. Slowing light is of course very common. The speed of light ~300,000,000 m/s is only in a vacuum. If light is propagating in any other medium, its electric and magnetic components interact with the substance, slowing its speed. It is not an "ancient theory", Einstien wrote his principles of special relativity in 1905, and his "assumptions" still hold true today. If you want to talk about "ancient history", note the fact that it is presently theorized that the speed of light was faster in the past, and that its "constant" value is slightly changing slowing over billions of years. Any experiment showing that the speed limit of light be varifiably broken in a laboratory would be headline news, and everyone would be aware of it.
Pentcho Valev

Sofia, Bulgaria

#5 Dec 2, 2006
EINSTEIN'S PRINCIPLE OF VARIABILITY OF THE SPEED OF LIGHT

Einstein's 1911 equation c'=c(1+V/c^2), where c' is the speed of light as measured by an observer, c=300000km/s is the initial speed of light relative to the light source and V is the gravitational potential relative to the point where light is emitted, proves the validity of the following principle:

Since the probability that V=0 is virtually zero, light NEVER travels in space with speed c=300000km/s; its speed is either higher or lower than that value (V>0 or V<0).

Pentcho Valev
[email protected]
Brandon
#6 Dec 2, 2006
Pentcho Valev wrote:
EINSTEIN'S PRINCIPLE OF VARIABILITY OF THE SPEED OF LIGHT
Einstein's 1911 equation c'=c(1+V/c^2), where c' is the speed of light as measured by an observer, c=300000km/s is the initial speed of light relative to the light source and V is the gravitational potential relative to the point where light is emitted, proves the validity of the following principle:
Since the probability that V=0 is virtually zero, light NEVER travels in space with speed c=300000km/s; its speed is either higher or lower than that value (V>0 or V<0).
Pentcho Valev
[email protected]
It is interesting that you chose this equation as an explanation for the propagation of light. This is proof that you don't know what you are talking about, and are doing random searches on the internet for information you don't understand. You are just spreading false information, and no one knows who you are, so why are you trying to sound smart?

The fact of the matter is that in 1911, 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. So the following equation IS the best equation we have that describes the path of light in an idealized non-zero gravitational field:

:$ds^{2}=-c^2 \left(1-\frac{2GM}{c^2 r}\right) dt^2 +\left(1-\frac{2GM}{c^2 r}\right)^{-1}dr^2+ r^2 d\Omega^2$

And this equation does not imply a possibility for light to exceed c.
Guanto
#7 Dec 12, 2006
KOKO

Macedonia

#8 Dec 14, 2006
Similar experiment was conducted at CERN couple of years ago, as I remember it turn out that it was not the case that the speed of light was exceeded, but the chamber was just shifting the center of the wave package being sent. (The light impuls being the wave package)
Pentcho Valev

Sofia, Bulgaria

#9 Dec 16, 2006
BEYOND EINSTEIN: NEWTON

Einstein's theory is an inconsistency: the set of its axioms involves, explicitly, the principle of INVARIABILITY of the speed of light and, implicitly, the principle of VARIABILITY of the speed of light. Any development, improvement etc. should obviously be preceded by a removal of the false principle of invariability of the speed of light and the miracles it has generated (time dilation, length contraction, Minkowski's spacetime etc.). "Relativity without Einstein's second postulate" has been a recurrent dream of initiated Einsteinians who have known about the falsehood from the very beginning:

http://www.worldscibooks.com/physics/4114.htm... :
"They lead to an unexpected affirmative answer to the long-standing question of whether it is possible to construct a relativity theory without postulating the constancy of the speed of light and retaining only the first postulate of special relativity. This question was discussed in the early years following the discovery of special relativity by many physicists, including Ritz, Tolman, Kunz, Comstock and Pauli, all of whom obtained negative answers."

The problem is that "Relativity without Einstein's second postulate" or, in other terms, "Relativity without c", is equivalent to "Back to Newton". Curiously, the proof of this equivalency can be found in perhaps the most famous textbook on relativity:

http://www.courses.fas.harvard.edu/~phys16/Te...
p.35: "Relativity without c....it is easy to imagine a universe where the speed of light depends on the frame of reference. Light could behave like a baseball, for example. So let's drop the speed of light postulate and see what we can say about the coordinate transformations between frames, using only the relativity postulate."
p.38: "There is only one decision to be made when constructing the spacetime structure of an (empty) universe. You just have to say whether V is finite or infinite, that is, whether the universe is Lorentzian or Galilean."

Note that "Light could behave like a baseball" amounts to an implicit introduction of Newton's particle model of light (confirmed by Einstein himself in 1905) valid in a Galilean universe where the speed of light is VARIABLE.

Pentcho Valev
[email protected]
Pentcho Valev

Sofia, Bulgaria

#10 Dec 18, 2006
EDUCATION IN EINSTEIN'S WORLD

http://www.sussex.ac.uk/Units/publications/sa...
Courses at Sussex
Physics and astronomy
Relativity
Level 1
6 credits in summer
Teaching method: Lecture, Workshop
Assessment modes: Unseen Examination, Coursework
Topics include: historical perspective. Inertial frames and transformations. NewtonÂ’s laws in inertial frames. MICHELSON-MORLEY EXPERIMENT - OBSERVED CONSTANCY OF SPEED OF LIGHT. EinsteinÂ’s assumptions. Lorentz-Einstein transformations; Minkowski diagrams; Lorentz contraction; time dilation. Transformation of velocities - stellar aberration. Variation of mass, mass-energy equivalence. Lorentz transformations for momentum and energy.

http://www.hawking.org.uk/lectures/dice.html
Stephen Hawking: "But a famous experiment, carried out by two Americans, Michelson and Morley in 1887, showed that light always travelled at a speed of one hundred and eighty six thousand miles a second, no matter where it came from."

Elsewhere Einstein's educators teach:
http://en.wikipedia.org/wiki/Speed_of_light :
"It should be noted that the Michelson-Morley experiment said little about the speed of light relative to the lightÂ’s source and observerÂ’s velocity, as both the source and observer were travelling at the same velocity together in space. Indeed, if light is understood to be due to quantum photon Â“bulletsÂ”, then the Michelson-Morley result is exactly as expected."

Amazingly, this type of education has proved extremely efficient - no relativist would see anything disturbing when comparing the three teachings.

Pentcho Valev
[email protected]
Pentcho Valev

Sofia, Bulgaria

#11 Dec 19, 2006
TESTING EINSTEIN'S INCONSISTENCY

http://www.spaceref.com/news/viewpr.html...
"KAMUELA, Hawaii (December 18, 2006) The National Science Foundation (NSF) has awarded the W. M. Keck Observatory $2 million to improve the sensitivity and resolution of the Keck Interferometer. The improvements will enable the instrument to detect Jupiter-sized planets around other stars and test predictions of Einstein's general theory of relativity in the chaotic core of our galaxy." Einsteinians would like to test both the corollaries of Einstein's principle of INVARIABILITY of speed of light and the corollaries of Einstein's principle of VARIABILITY of speed of light. However they find$2 million insufficient. So far Einsteinians have wasted billions and yet even the fact that Einstein's theory is based on two incompatible principles remains somewhat obscure.

Pentcho Valev
[email protected]
Pentcho Valev

Sofia, Bulgaria

#12 Dec 19, 2006
DANGEROUS BUSINESS IN EINSTEIN'S CRIMINAL CULT

Classically, Einstein's criminal cult extracted their billions from miracles deduced from Einstein's false principle of constancy of the speed of light. However a few years ago Einsteinians realized in horror that taxpayers were not excited anymore about a twin that sees his brother's clock running slow but then returns and proves younger etc. That was the end of the constant speed of light affair and a natural beginning of the variable speed of light affair.

The new business is dangerous for two reasons: first, variable speed of light could wipe out Einstein's criminal cult altogether; second, variable speed of light per se is unable to produce miracles and therefore excitement among taxpayers is by no means guaranteed. So new business plans involve the following tasks. First, the meaning of "variable" should be confused: the attention should shift from "depending on the speed of the light source" to something different, e.g. "faster in the past, slower now". Second, the variability of the speed of light should be served in fantastically small portions, so fantastically small that excitement is unavoidably restored and, what is even more important, Einstein's theory remains essentially correct:

http://www.discover.com/issues/sep-04/feature...
"Testing the Limit of EinsteinÂ’s Theories....IS THE SPEED OF LIGHT CONSTANT?....If you compare a lot of high-energy photons with a lot of relatively low-energy ones, you should find that on average, after a billion-year race, the high-energy ones reach GLASTÂ’s detector soonerÂ—by about a millisecond. He and other quantum gravity theorists are pretty excited by that possibility, which just goes to show what theyÂ’re up against."

Pentcho Valev
[email protected]
Pentcho Valev

Sofia, Bulgaria

#13 Dec 20, 2006
EINSTEIN'S RELATIVITY: VIOLATIONS AND AXIOMS

Any Einsteinian would tell you violations of the theory entail reconsideration of the axioms: since Einstein's deductions are rigorous, false conclusions would imply false axioms. On the other hand, any breathtaking development of Einstein's relativity can only be triggered by violations and Einsteinians do wish to see that development - the present stalemate is disturbing even for them. The dilemma has an elegant solution: there are numerous violations indeed so the breathtaking development is imminent but those violations are tiny, so tiny that reconsideration of the axioms is not necessary:

http://newsinfo.iu.edu/tips/page/normal/4519.... :
"Alan Kostelecky, Distinguished Professor of Physics at Indiana University Bloomington, has been elected a fellow of the American Association for the Advancement of Science "for seminal contributions to relativity and spacetime symmetries, and for the development of a profound and comprehensive theoretical framework for relativity violations," according to a statement from AAAS....he realized that tiny violations of Einstein's relativity could be an experimental signal of the long-sought underlying theory unifying all known forces and particles....Kostelecky's theory has inspired many searches for relativity violations around the world, and more are being performed..... "The ongoing search for relativity violations is an impressive interdisciplinary effort," Kostelecky said."

Einsteinians reassure themselves in the following way. Since the violations are tiny, axioms are just a little false and therefore virtually true. The reassurance is quite explicit sometimes:

http://www.discover.com/issues/sep-04/feature...
"Testing the Limit of EinsteinÂ’s Theories....IS THE SPEED OF LIGHT CONSTANT?....If you compare a lot of high-energy photons with a lot of relatively low-energy ones, you should find that on average, after a billion-year race, the high-energy ones reach GLASTÂ’s detector soonerÂ—by about a millisecond. He and other quantum gravity theorists are pretty excited by that possibility, which just goes to show what theyÂ’re up against."

Einsteinians know Einstein would disagree about "little falsehood". Once he said: "If the speed of light is the least bit affected by the speed of the light source, then my whole theory of relativity and theory of gravity is false." However the solution Einsteinians have found is both elegant and all-embracing: Violations are tiny, axioms are just a little false, Einstein is just a little wrong.

Pentcho Valev
[email protected]
Pentcho Valev

Sofia, Bulgaria

#14 Dec 23, 2006

http://arxiv.org/PS_cache/astro-ph/pdf/9910/9...
Gravitation Without Curved Space-time
Kris Krogh
p.12: "The gravitational frequency shift in EinsteinÂ’s 1911 variable-speed-of-light theory was v=v0(1+phi/c^2) which agrees with Eq.(13) to the first order. But there was no effect on lambda, or the dimensions of measuring rods, corresponding to Eq.(14). Consequently, the speed of light in a gravitational potential was c=c0(1+phi/c^2)."

Pentcho Valev
[email protected]
nakayama

Chiba, Japan

#15 Dec 26, 2006
In the space, an observer observes a star. When observer jets out gas and moves(in different uniform motions) along the light path, frequency of star light changes. But if light speed is constant(to observer), why frequency changes ? Speed of light is speed of light wave.
P.S. Change of wave length(it may be inevitable outcome from the theory of constancy of light speed) of the light path(from observer to the star) is unable to imagine.

http://www.geocities.jp/nak233/eng.html
Pentcho Valev

Sofia, Bulgaria

#16 Dec 27, 2006
THE FORGOTTEN FACET OF EINSTEIN'S THEORY

In 1964 Einsteinians discovered that Einstein's inconsistency, like any other inconsistency, is based on two incompatible principles: the principle of invariability of the speed of light and the principle of variability of the speed of light. They called the discovery "a previously forgotten facet of general relativity theory" and made use of it in the sense of extracting money from it:

http://www.blazelabs.com/f-g-gcont.asp :
"The first confirmation of a long range variation in the speed of light travelling in space came in 1964. Irwin Shapiro, it seems, was the first to make use of a previously forgotten facet of general relativity theory -- that the speed of light is reduced when it passes through a gravitational field. He had proposed an observational test to check his prediction: bounce radar beams off the surface of Venus and Mercury, and measure the round trip travel time. When the Earth, Sun, and Venus are most favorably aligned, Shapiro showed that the expected time delay, due to the presence of the Sun, of a radar signal traveling from the Earth to Venus and back, would be about 200 microseconds more than it would if the sun was not present. Later on, using the MIT Haystack radar antenna, the experiment was repeated, matching Shapiro's predicted amount of time delay. The experiments have been repeated many times since, with increasing accuracy. This experiment had for the first time shown that the constants like c and G, assumed constants in Einstein's SR theory suffered local (or regional) in the proximity of massive bodies like the sun. Faced with this evidence, Einstein stated: "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..."

Pentcho Valev
[email protected]
Pentcho Valev

Sofia, Bulgaria

#17 Dec 29, 2006
LAYING DOWN THE EINSTEIN'S LAWS

An interesting campaign has been launched by SCIENTIFIC AMERICAN:

http://blog.sciam.com/index.php...
Laying Down the Einstein's Laws

I offered Einstein's 1911 law of VARIABILITY of the speed of light (see comments). Perhaps Einsteinians will offer other laws: for instance, the law of the travelling twin who sees his brother's clock running slow all along but then returns and finds that in fact his brother's clock has been running fast all along.

Pentcho Valev
[email protected]
Pentcho Valev

Sofia, Bulgaria

#18 Dec 30, 2006
NEWTON WRONG IN EINSTEIN'S WORLD

J. Mulligan, INTRODUCTORY COLLEGE PHYSICS, McGraw-Hill, 1985, pp.631-632:
"Sir Isaac Newton had proposed a particle theory of light which explained the refraction of light by the difference in the forces exerted on the particles by the two media, the more dense medium exerting a larger force and causing light to move more rapidly. A measurement of the speed of light in water, made by Foucault in 1850, clearly showed that light has a lower speed in water than in air, and that Newton's theory must therefore be wrong."

If Newton's theory is wrong the more dense medium cannot cause light to move more rapidly (if it can Newton's theory is right). The educator should have stated clearly: Newton wrong means the speed of light is constant (does not vary with position) in either medium, only at the boundary it suddenly changes. However the educator knows Newton is right. Even Einstein knew Newton was right:

"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. One can do a simple Huyghens reconstruction of a wave front, taking into account the different speed of advance of the wavefront at different distances from the star (variation of speed of light), to derive the deflection of the light by the star.
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 / c2 )
where V is the gravitational potential relative to the point where the speed of light c0 is measured."

http://math.ucr.edu/home/baez/physics/Relativ...
"Einstein went on to discover a more general theory of relativity which explained gravity in terms of curved spacetime, and he talked about the speed of light changing in this new theory. In the 1920 book "Relativity: the special and general theory" he wrote:... 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 [...] 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. Since Einstein talks of velocity (a vector quantity: speed with direction) rather than speed alone, it is not clear that he meant the speed will change, but the reference to special relativity suggests that he did mean so."

As for the fact that light has a lower speed in water than in air, it is irrelevant. As the photon enters the more dense medium (water), its INITIAL speed is higher than the speed it had in the less dense medium (air) before the acceleration. So far Newton is right. If Newton thought this initial high speed in the more dense medium remained constant all along then he was mistaken but the mistake is immaterial. His theory of refraction based on the concept of variable speed of light remains correct.

Pentcho Valev
[email protected]
Pentcho Valev

Sofia, Bulgaria

#19 Jan 1, 2007
HOW SCIENCE SHOULD BE WRITTEN

http://www.amazon.com/Principle-Relativity-Do...
The Principle of Relativity (Dover Books on Physics)(Paperback) by Albert Einstein, Frances A. Davis....How science should be written...Reviewer: Professor Joseph L. McCauley (Austria+Texas):

"The constancy of the speed of light follows from the requirement that there is no special reference frame."

This absurdity was first introduced by Albert Einstein in Chaper 7 in his "Relativity". Scientists immediately realized that was the way science should be written and have written so for a century. The result is simple: No science left.

Pentcho Valev
[email protected]
Pentcho Valev

Sofia, Bulgaria

#20 Jan 4, 2007
HOW EINSTEINIANS EARN THEIR LIVING

http://www.amazon.com/Faster-Than-Speed-Light...
"In Faster Than the Speed of Light, Magueijo reveals the short, brilliant history of his possibly groundbreaking speculation--VSL, or Variable Light Speed. This notion--that the speed of light changed as the universe expanded after the Big Bang--contradicts no less prominent a figure than Albert Einstein. Because of this, Magueijo has suffered more than a few slings and arrows from hidebound, jealous, or perplexed colleagues. But the young scientist persisted, found a few important allies, and finally managed to shake up the establishment enough to get the attention he merited and craved."

Einstein defined the variability of the speed of light as the dependence of the speed of photons on the speed of the light source. The application of the equivalence principle converts this into the statement that, in a gravitational field, the speed of light "varies with position", as Einstein himself put it in Chapter 22 in his "Relativity" (but did not say that varying with position in a gravitational field is equivalent to depending on the speed of the light source in the absence of a gravitational field).

It is easy to see that Magueijo's Variable Light Speed in fact confirms Einstein's second postulate - the principle of INVARIABILITY of the speed of light. One would be unable to claim that light was faster in the past and is slower now if its speed were not invariable relative to the speed of the light source or in a gravitational field. Then why should Magueijo be presented as the Martyr contradicting Divine Albert and persecuted by jealous colleagues? Money, money, money......

Pentcho Valev
[email protected]

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