Richard Feynman's Misinterpretation of the Michelson-Morley experiment
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Pentcho Valev
2017-08-08 07:47:36 UTC
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Richard Feynman: "Another consequence of the [Maxwell's] equations is that if the source of the disturbance is moving, the light emitted goes through space at the same speed c. This is analogous to the case of sound, the speed of sound waves being likewise independent of the motion of the source. This independence of the motion of the source, in the case of light, brings up an interesting problem: Suppose we are riding in a car that is going at a speed u, and light from the rear is going past the car with speed c. Differentiating the first equation in (15.2) gives dx'/dt=dx/dt-u, which means that according to the Galilean transformation the apparent speed of the passing light, as we measure it in the car, should not be c but should be c-u. For instance, if the car is going 100,000 mi/sec, and the light is going 186,000 mi/sec, then apparently the light going past the car should go 86,000 mi/sec. In any case, by measuring the speed of the light going past the car (if the Galilean transformation is correct for light), one could determine the speed of the car. A number of experiments based on this general idea were performed to determine the velocity of the earth, but they all failed - they gave no velocity at all. We shall discuss one of these experiments [the Michelson-Morley experiment] in detail..." http://www.feynmanlectures.caltech.edu/I_15.html

The Michelson-Morley experiment was not based "on this general idea", that is, on the assumption that "the Galilean transformation is correct for light". Rather, it was based on the opposite assumption - that the Galilean transformation is wrong for light and the speed of light is independent of the motion of the source. It was this opposite assumption that was refuted by the null result of the experiment.

If the calculations are made on the assumption that the speed of light does depend on the motion of the source, as predicted by the Galilean transformation, then the null result of the experiment confirms the assumption. Consider Feynman's further analysis:

Richard Feynman: "First, let us calculate the time required for the light to go from B to E and back. Let us say that the time for light to go from plate B to mirror E is t_1, and the time for the return is t_2. Now, while the light is on its way from B to the mirror, the apparatus moves a distance ut_1, so the light must traverse a distance L + ut_1, at the speed c."

Feynman's last phrase,

"at the speed c",

is an abridged version of the assumption "The speed of light is independent of the motion of the source". If, instead of "at the speed c", we have a new premise,

"at the speed c + u",

taken from the Galilean transformation, the calculation (based on the new premise) will give a new prediction,

t_1 + t_2 = 2t_3 = 2L/c,

which exactly matches the null result of the Michelson-Morley experiment.

In 1887 (prior to FitzGerald and Lorentz advancing the ad hoc length contraction hypothesis) the Michelson-Morley experiment UNEQUIVOCALLY confirmed the variable speed of light posited by the Galilean transformation (Newton's emission theory of light) and refuted the constant (independent of the speed of the motion of the source) speed of light posited by the ether theory and later adopted by Einstein as his 1905 second ("light") postulate:

"To it, we should add that the null result of the Michelson-Morley experiment was unhelpful and possibly counter-productive in Einstein's investigations of an emission theory of light, for the null result is predicted by an emission theory."

"Emission theory, also called emitter theory or ballistic theory of light, was a competing theory for the special theory of relativity, explaining the results of the Michelson–Morley experiment of 1887. [...] The name most often associated with emission theory is Isaac Newton. In his corpuscular theory Newton visualized light "corpuscles" being thrown off from hot bodies at a nominal speed of c with respect to the emitting object, and obeying the usual laws of Newtonian mechanics, and we then expect light to be moving towards us with a speed that is offset by the speed of the distant emitter (c ± v)."

"The Michelson-Morley experiment is fully compatible with an emission theory of light that CONTRADICTS THE LIGHT POSTULATE."

Albert Einstein: "...I introduced the principle of the constancy of the velocity of light, which I borrowed from H. A. Lorentz's theory of the stationary luminiferous ether..."

Banesh Hoffmann, Relativity and Its Roots, p.92: "Moreover, if light consists of particles, as Einstein had suggested in his paper submitted just thirteen weeks before this one, the second principle seems absurd: A stone thrown from a speeding train can do far more damage than one thrown from a train at rest; the speed of the particle is not independent of the motion of the object emitting it. And if we take light to consist of particles and assume that these particles obey Newton's laws, they will conform to Newtonian relativity and thus automatically account for the null result of the Michelson-Morley experiment without recourse to contracting lengths, local time, or Lorentz transformations. Yet, as we have seen, Einstein resisted the temptation to account for the null result in terms of particles of light and simple, familiar Newtonian ideas, and introduced as his second postulate something that was more or less obvious when thought of in terms of waves in an ether. If it was so obvious, though, why did he need to state it as a principle? Because, having taken from the idea of light waves in the ether the one aspect that he needed, he declared early in his paper, to quote his own words, that "the introduction of a 'luminiferous ether' will prove to be superfluous."

Richard Feynman: "I want to emphasize that light comes in this form - particles. It is very important to know that light behaves like particles, especially for those of you who have gone to school, where you probably learned something about light behaving like waves. I'm telling you the way it does behave - like particles. You might say that it's just the photomultiplier that detects light as particles, but no, every instrument that has been designed to be sensitive enough to detect weak light has always ended up discovering the same thing: light is made of particles." QED: The Strange Theory of Light and Matter p. 15

Pentcho Valev
Pentcho Valev
2017-08-08 16:01:56 UTC
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According to Tim Maudlin, Richard Feynman misinterpreted the twin paradox as well:

Tim Maudlin: "...so many physicists strongly discourage questions about the nature of reality. The reigning attitude in physics has been "shut up and calculate": solve the equations, and do not ask questions about what they mean. But putting computation ahead of conceptual clarity can lead to confusion. Take, for example, relativity's iconic "twin paradox." Identical twins separate from each other and later reunite. When they meet again, one twin is biologically older than the other. (Astronaut twins Scott and Mark Kelly are about to realize this experiment: when Scott returns from a year in orbit in 2016 he will be about 28 microseconds younger than Mark, who is staying on Earth.) No competent physicist would make an error in computing the magnitude of this effect. But even the great Richard Feynman did not always get the explanation right. In "The Feynman Lectures on Physics," he attributes the difference in ages to the acceleration one twin experiences: the twin who accelerates ends up younger. But it is easy to describe cases where the opposite is true, and even cases where neither twin accelerates but they end up different ages. The calculation can be right and the accompanying explanation wrong." http://www.pbs.org/wgbh/nova/blogs/physics/2015/04/physics-needs-philosophy/

Perhaps Feynman, like other Einsteinians, believed that the acceleration is both crucial and immaterial - George Orwell calls this doublethink. Einsteinians have discovered that doublethink (believing and teaching both thesis and antithesis) not only destroys human rationality but makes the process irreversible - the affected person never restores his/her sanity. The slogan is: "Don't just repeat the lie - repudiate it from time to time. Victims get permanently paralyzed and Divine Albert's Divine Theory rules forever."

Einstein was a powerful doublethinker. He was able to defend both thesis and antithesis with the same conviction, without any hesitation. So in 1911 he explained to the gullible world that the "sudden change of direction" is immaterial with respect to the clock (twin) paradox:

Albert Einstein 1911: "The clock runs slower if it is in uniform motion, but if it undergoes a change of direction as a result of a jolt, then the theory of relativity does not tell us what happens. The sudden change of direction might produce a sudden change in the position of the hands of the clock. However, the longer the clock is moving rectilinearly and uniformly with a given speed in a forward motion, i.e., the larger the dimensions of the polygon, the smaller must be the effect of such a hypothetical sudden change."

In 1918 the "sudden change of direction" involving acceleration, which had been immaterial a couple of years before, became crucial and produced a miraculous HOMOGENEOUS gravitational field:

Albert Einstein 1918: "A homogeneous gravitational field appears, that is directed towards the positive x-axis. Clock U1 is accelerated in the direction of the positive x-axis until it has reached the velocity v, then the gravitational field disappears again. An external force, acting upon U2 in the negative direction of the x-axis prevents U2 from being set in motion by the gravitational field. [...] According to the general theory of relativity, a clock will go faster the higher the gravitational potential of the location where it is located, and during partial process 3 U2 happens to be located at a higher gravitational potential than U1. The calculation shows that this speeding ahead constitutes exactly twice as much as the lagging behind during the partial processes 2 and 4."

Today's Einsteinians believe that the "sudden change of direction" involving acceleration is both immaterial and crucial, but most of them teach Einstein's 1911 argument (it is easier to teach). Yet an important minority sticks to Einstein's 1918 idiocy and teaches that the "sudden change of direction" is crucial:

Don Lincoln: "Some readers, probably including some of my doctoral-holding colleagues at Fermilab, will claim that the difference between the two twins is that one of the two has experienced an acceleration. (After all, that's how he slowed down and reversed direction.) However, the relativistic equations don't include that acceleration phase; they include just the coasting time at high velocity."

Gary W. Gibbons FRS: "In other words, by simply staying at home Jack has aged relative to Jill. There is no paradox because the lives of the twins are not strictly symmetrical. This might lead one to suspect that the accelerations suffered by Jill might be responsible for the effect. However this is simply not plausible because using identical accelerating phases of her trip, she could have travelled twice as far. This would give twice the amount of time gained."

Don Lincoln: "A common explanation of this paradox is that the travelling twin experienced acceleration to slow down and reverse velocity. While it is clearly true that a single person must experience this acceleration, you can show that the acceleration is not crucial. What is crucial is that the travelling twin experienced time in two reference frames, while the homebody experienced time in one. We can demonstrate this by a modification of the problem. In the modification, there is still a homebody and a person travelling to a distant star. The modification is that there is a third person even farther away than the distant star. This person travels at the same speed as the original traveler, but in the opposite direction. The third person's trajectory is timed so that both of them pass the distant star at the same time. As the two travelers pass, the Earthbound person reads the clock of the outbound traveler. He then adds the time he experiences travelling from the distant star to Earth to the duration experienced by the outbound person. The sum of these times is the transit time. Note that no acceleration occurs in this problem...just three people experiencing relative inertial motion."

John Norton: "We read from these hypersurfaces that the traveling twin judges the stay-at-home twin's clock to be running at half the speed of the travelers. When the traveler's clock reads 1 day, the stay-at-home twin's reads 1/2 day; just before the turn around, when the traveler's clock is almost at 2 days, the stay-at-home twin's clock is almost at 1 day. Then, at the end of the outward leg, the traveler abruptly changes motion, accelerating sharply to adopt a new inertial motion directed back to earth. What comes now is the key part of the analysis. The effect of the change of motion is to alter completely the traveler's judgment of simultaneity. The traveler's hypersurfaces of simultaneity now flip up dramatically. Moments after the turn-around, when the travelers clock reads just after 2 days, the traveler will judge the stay-at-home twin's clock to read just after 7 days. That is, the traveler will judge the stay-at-home twin's clock to have jumped suddenly from reading 1 day to reading 7 days. This huge jump puts the stay-at-home twin's clock so far ahead of the traveler's that it is now possible for the stay-at-home twin's clock to be ahead of the travelers when they reunite. Careful attention to the differing judgments of simultaneity of the two twins shows that there is nothing paradoxical in the twin effect. The brief moment of acceleration of the traveling twin completely alters the traveler's judgments of simultaneity and this alteration is key to seeing how relativity provides a consistent account of the effect."

"The Twin Paradox is a scenario that, at first glance, seems to make nonsense out of Einstein's theory of special relativity. The situation is that a man sets off in a rocket travelling at high speed away from Earth, whilst his twin brother stays on Earth. [...] What happens is that the twin on Earth, viewing himself as stationary and his brother as moving at high speed, sees his brother experiencing time dilation and thus ageing more slowly. At the same time, the twin in the spaceship considers himself to be the stationary twin, and therefore as he looks back towards Earth he sees his brother ageing more slowly than himself. Each sees the other as moving, and therefore as experiencing time dilation. But which brother is "correct" in the way he perceives the situation? Both are. Each sees the other as being younger than himself. How they were perceived by any onlooker would depend on which frame of reference the onlooker was in. It doesn't make sense to ask which brother is "really" older, because the answer depends on where you stand to ask the question! But what about when the brother in the spaceship returns to Earth? Surely the contradiction will be apparent then? Ah, but in order to return to Earth, the spaceship must slow down, stop moving, turn around and go back the other way. During those periods of deceleration and deceleration, it is not an inertial frame and therefore the normal rules of special relativity don't apply. When the twin in the spaceship turns around to make his journey home, the shift in his frame of reference causes his perception of his brother's age to change rapidly: he sees his brother getting suddenly older. This means that when the twins are finally reunited, the stay-at-home twin is the older of the two."

The sudden ageing syndrome described in the last two quotations (and in Einstein's 1918 paper) deserves special attention - this is perhaps the greatest idiocy in the history of science:

"When the twin in the spaceship turns around to make his journey home, the shift in his frame of reference causes his perception of his brother's age to change rapidly: he sees his brother getting suddenly older. This means that when the twins are finally reunited, the stay-at-home twin is the older of the two."

Pentcho Valev
Pentcho Valev
2017-08-09 09:38:12 UTC
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Richard Feynman: "I want to emphasize that light comes in this form - particles. It is very important to know that light behaves like particles, especially for those of you who have gone to school, where you probably learned something about light behaving like waves. I'm telling you the way it does behave - like particles. You might say that it's just the photomultiplier that detects light as particles, but no, every instrument that has been designed to be sensitive enough to detect weak light has always ended up discovering the same thing: light is made of particles." QED: The Strange Theory of Light and Matter, p. 15 http://www.amazon.com/QED-Strange-Theory-Light-Matter/dp/0691024170

Here Feynman is correct. As far as its speed is concerned, light does indeed behave like particles. Its speed varies with the speed of the source, like the speed of ordinary projectiles, and it accelerates in a gravitational field just as falling bodies do (in the gravitational field of the Earth the acceleration of falling photons is g). Consider this:

Paul Fendley: "First consider light shined downward in a freely falling elevator of height h. [...] By the time the light hits the bottom of the elevator, it [the elevator] is accelerated to some velocity v. [...] We thus simply have v=gt=gh/c. [...] Now to the earth frame. When the light beam is emitted, the elevator is at rest, so earth and elevator agree the frequency is f. But when it hits the bottom, the elevator is moving at velocity v=gh/c with respect to the earth, so earth and elevator must measure different frequencies. In the elevator, we know that the frequency is still f, so on the ground the frequency f'=f(1+v/c)=f(1+gh/c^2). On the earth, we interpret this as meaning that not only does gravity bend light, but changes its frequency as well." https://www.yumpu.com/en/document/view/39953570/lecture-35-paul-fendley

Substituting f=c/λ (λ is the wavelength) into Fendley's equations gives:

f' = f(1+v/c) = f(1+gh/c^2) = (c+v)/λ = c(1+gh/c^2)/λ = c'/λ


c' = c+v = c(1+gh/c^2)

is the speed of light relative to an observer on the ground or, equivalently, relative to an observer in gravitation-free space moving with speed v towards the emitter. Clearly the speed of light varies with both the gravitational potential and the speed of the observer, as predicted by Newton's emission theory of light and in violation of Einstein's relativity. Many scientists know and sometimes even teach that, more or less explicitly:

"If we accept the principle of equivalence, we must also accept that light falls in a gravitational field with the same acceleration as material bodies." http://sethi.lamar.edu/bahrim-cristian/Courses/PHYS4480/4480-PROBLEMS/optics-gravit-lens_PPT.pdf

University of Illinois at Urbana-Champaign: "Consider a falling object. ITS SPEED INCREASES AS IT IS FALLING. Hence, if we were to associate a frequency with that object the frequency should increase accordingly as it falls to earth. Because of the equivalence between gravitational and inertial mass, WE SHOULD OBSERVE THE SAME EFFECT FOR LIGHT. So lets shine a light beam from the top of a very tall building. If we can measure the frequency shift as the light beam descends the building, we should be able to discern how gravity affects a falling light beam. This was done by Pound and Rebka in 1960. They shone a light from the top of the Jefferson tower at Harvard and measured the frequency shift. The frequency shift was tiny but in agreement with the theoretical prediction. Consider a light beam that is travelling away from a gravitational field. Its frequency should shift to lower values. This is known as the gravitational red shift of light." https://courses.physics.illinois.edu/phys419/sp2011/lectures/Lecture13/L13r.html

Albert Einstein Institute: "One of the three classical tests for general relativity is the gravitational redshift of light or other forms of electromagnetic radiation. However, in contrast to the other two tests - the gravitational deflection of light and the relativistic perihelion shift -, you do not need general relativity to derive the correct prediction for the gravitational redshift. A combination of Newtonian gravity, a particle theory of light, and the weak equivalence principle (gravitating mass equals inertial mass) suffices. [...] The gravitational redshift was first measured on earth in 1960-65 by Pound, Rebka, and Snider at Harvard University..." http://www.einstein-online.info/spotlights/redshift_white_dwarfs

"Let's say you, the observer, now move toward the source with velocity vo. You encounter more waves per unit time than you did before. Relative to you, the waves travel at a higher speed: v'=v+vo. The frequency of the waves you detect is higher, and is given by: f'=v'/λ=(v+vo)/λ." http://physics.bu.edu/~redner/211-sp06/class19/class19_doppler.html

"vo is the velocity of an observer moving towards the source. This velocity is independent of the motion of the source. Hence, the velocity of waves relative to the observer is c + vo. [...] The motion of an observer does not alter the wavelength. The increase in frequency is a result of the observer encountering more wavelengths in a given time." http://a-levelphysicstutor.com/wav-doppler.php

Pound, Rebka and Snider knew that their experiments had confirmed the variation of the speed of light predicted by Newton's emission theory of light, not the gravitational time dilation predicted by Einstein's relativity:

R. V. Pound and G. A. Rebka, Jr, APPARENT WEIGHT OF PHOTONS http://journals.aps.org/prl/pdf/10.1103/PhysRevLett.4.337

R. V. Pound and J. L. Snider, Effect of Gravity on Gamma Radiation: "It is not our purpose here to enter into the many-sided discussion of the relationship between the effect under study and general relativity or energy conservation. It is to be noted that no strictly relativistic concepts are involved and the description of the effect as an "apparent weight" of photons is suggestive. The velocity difference predicted is identical to that which a material object would acquire in free fall for a time equal to the time of flight." http://virgo.lal.in2p3.fr/NPAC/relativite_fichiers/pound.pdf

Pentcho Valev