School encyclopedia. Huygens principle
And the pood as it was - it is, sixteen kilograms.
M. Tanich (from the song to the film "Mysterious Monk")
Special theory of relativity (SRT) is undoubtedly the most famous of physical theories. The popularity of SRT is associated with the simplicity of its basic principles, the striking paradox of its conclusions and its key position in physics of the twentieth century. SRT brought unprecedented fame to Einstein, and this fame became one of the reasons for the tireless attempts to revise the theory. Among professionals, the disputes around the service station stopped more than half a century ago. But to this day, the editors of physics journals are constantly besieged by amateurs who propose options for revising the SRT. And, in particular, the second postulate, which asserts the constancy of the speed of light for all inertial frames of reference and its independence from the speed of the source (in other words, in whatever direction from the observer and at whatever speed the observed object moves, the light beam sent from it would have all the same speed, approximately equal to 300 thousand kilometers per second, no more and no less).
Critics of SRT, for example, argue that the speed of light is not constant at all, but changes for the observer depending on the speed of the source (ballistic hypothesis) and only the imperfection of the measuring technique does not allow to prove this experimentally. The ballistic hypothesis goes back to Newton, who considered light as a stream of particles, the speed of which decreases in a refractive medium. This view was revived with the advent of the Planck-Einstein photon concept, which gave a convincing visualization to the idea of adding the speed of light to the speed of a source, by analogy with the speed of a projectile ejected from a moving gun.
In our time, of course, such naive attempts to revise SRT cannot get into serious scientific publications, but they overwhelm the media and the Internet, which has a very sad effect on the state of mind of the mass reader, including schoolchildren and students.
Attacks on Einstein's theory - both at the beginning of the last century and now - are motivated by discrepancies in the assessment and interpretation of the results of experiments to measure the speed of light, the first of which, by the way, was carried out back in 1851 by the outstanding French scientist Armand Hippolyte Louis Fizeau. In the middle of the last century, this prompted the then president of the USSR Academy of Sciences, SI Vavilov, to attend to the development of a project to demonstrate the independence of the speed of light from the speed of the source.
By that time, the postulate of the independence of the speed of light was directly confirmed only by astronomical observations of binary stars. According to the Dutch astronomer Willem de Sitter, if the speed of light depends on the speed of the source, the trajectories of the binary stars should be qualitatively different from the observed ones (consistent with celestial mechanics). However, this argument met with an objection related to taking into account the role of interstellar gas, which, as a refractive medium, was considered as a secondary source of light. Critics argued that the light emitted by the secondary source "loses memory" of the speed of the primary source as it propagates through the interstellar medium, because the source's photons are absorbed and then re-emitted by the medium again. Since data about this medium are known only with very large assumptions (as well as absolute values of distances to stars), this position made it possible to question most of the astronomical evidence of the constancy of the speed of light.
SI Vavilov proposed to his doctoral student AM Bonch-Bruevich to design a setup in which a beam of fast excited atoms would become a light source. In the process of detailed elaboration of the experiment plan, it turned out that there was no chance of a reliable result, since the technology of that time did not allow obtaining beams of the required speed and density. The experiment was never carried out.
Since then, various attempts to experimentally prove the second postulate of SRT have been made more than once. The authors of the corresponding works came to the conclusion about the validity of the postulate, which, however, did not stop the flow of critical speeches, in which either objections were raised against the ideas of experiments, or their accuracy was questioned. The latter was associated, as a rule, with the insignificance of the attainable speed of the radiation source in comparison with the speed of light.
However, today physics has a tool to return to the proposal of SI Vavilov. This is a synchrotron emitter, where a very bright light source is a bunch of electrons moving along a curved trajectory at a speed almost indistinguishable from the speed of light with... Under these conditions, it is easy to measure the speed of the emitted light in an impeccable laboratory vacuum. According to the logic of the supporters of the ballistic hypothesis, this speed should be equal to twice the speed of light from a stationary source! It would not be difficult to detect such an effect (if it exists): it is enough to simply measure the time a light pulse passes a measured segment in an evacuated space.
Of course, for professional physicists there is no doubt about the expected result. In this sense, experience is useless. However, direct demonstration of the constancy of the speed of light is of great didactic value, limiting the ground for further speculations about the lack of proof of the foundations of the theory of relativity. Physics in its development constantly returned to the reproduction and refinement of the fundamental experiments carried out with new technical capabilities. In this case, the goal is not to clarify the speed of light. We are talking about making up for a historical flaw in the experimental substantiation of the origins of SRT, which should facilitate the perception of this rather paradoxical theory. We can say that we are talking about a demonstration experiment for future physics textbooks.
Such an experiment was recently carried out by a group of Russian scientists at the Kurchatov Synchrotron Radiation Center of the NRC KI. In the experiments, a source of synchrotron radiation (SR), an electron storage ring "Siberia-1", was used as a pulsed light source. SR of electrons accelerated to relativistic speeds (close to the speed of light) has a wide spectrum from infrared and visible to X-ray range. Radiation propagates in a narrow cone along a tangent to the trajectory of electrons along the abstraction channel and is removed through a sapphire window into the atmosphere. There, the light is collected by a lens onto the photocathode of a fast photodetector. A beam of light on its way in a vacuum could be covered by a glass plate introduced by means of a magnetic drive. At the same time, according to the logic of the ballistic hypothesis, the light, which had presumably doubled the speed of 2 with, after the window should have regained normal speed with.
The electron bunch had a length of about 30 cm. Passing by the derivation window, it generated an SR pulse with a duration of about 1 ns in the channel. The frequency of rotation of the bunch along the synchrotron ring was ~ 34.5 MHz, so that a periodic sequence of short pulses was observed at the output of the photodetector, which was recorded using a high-speed oscilloscope. The pulses were synchronized by a signal of a high-frequency electric field of the same frequency of 34.5 MHz, which compensated for the loss of electron energy by SR. Comparing two oscillograms obtained in the presence of a glass window in the SR beam and in its absence, it was possible to measure the lag of one sequence of pulses from the other, caused by a hypothetical decrease in velocity. With a length of 540 cm of the section of the SR derivation channel from the window introduced into the beam to the exit into the atmosphere, a decrease in the speed of light from 2 with before with should have resulted in a 9 ns time shift. Experimentally, no shift was observed with an accuracy of the order of 0.05 ns.
In addition to the experiment, a direct measurement of the speed of light in the retraction channel was carried out by dividing the channel length by the pulse propagation time, which led to a value only 0.5% below the tabular speed of light.
So, the results of the experiment turned out, of course, to be expected: the speed of light does not depend on the speed of the source, in full accordance with Einstein's second postulate. What's new is that it was first confirmed by direct measurement of the speed of light from a relativistic source. It is unlikely that this experiment will stop the attacks on the SRT from the jealous of Einstein's fame, but it will significantly limit the field of new claims.
The details of the experiment are described in an article to be published in one of the upcoming issues of the journal Uspekhi Fizicheskikh Nauk.
See also:
E. B. Alexandrov. , "Chemistry and Life", No. 3, 2012 (in more detail about this experiment).
Show comments (98)
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I will clarify: I have already read this article. BEFORE your message. And it was not about the deviation of the speed of light, but about the deviation of the speed of NEUTRINO from the speed of light. Do you catch the difference?;)
By the way, if the assumption is confirmed and there is a way to exchange signals with a speed greater than light, the zero, "absolute" coordinate system will be determined with all the evidence - in view of what has already been stated in my commentary. True, for me the experiment with neutrinos is still dubious. We are waiting for confirmation or denial from other laboratories!
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I was referring to a note on tracking a geostationary satellite. I am more than calm about the superluminal neutrino. Firstly, the existence of the muon neutrino was predicted a long time ago, and secondly, the speed of the photon was measured first precisely because a person perceives them directly. The discovery of elementary particles with a speed significantly exceeding the speed of light is a matter of time. This is my private point of view. If only because the human toolkit has expanded pretty well.
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For a companion? I haven't read it ... I'll have to take a look :)
As for the particles, we'll wait. It's funny if it turns out that we are just "Lorentzian fish" swimming in an ordinary multiverse pond with a specific speed of propagation of basic interactions. Therefore, we distort depending on the speed according to the local Lorentz transformations, measure it with a clock that lags behind it, and therefore we cannot find out either the speed relative to our own pond, or our own distortion-decelerations (but how if all our clocks and rulers are buggy with us ?). Yes, particles moving faster than the standard perturbations of our "reservoir" will help us calculate it. But for now ... So far, everything is too vague and shaky - and therefore the theory of curvatures of space-time, metric tensor, multidimensional interval in Minkovsky space has no less grounds.To answer
So what is your attitude towards measurements of the parameters of motion of the Earth and the Solar system? Or did "gentlemen kefirshchiki" measure with "buggy rulers"? Your point of view does not give you the right to express it with contempt for opponents. Just a few seconds ago, by geological standards, for your views, you would first have been pulled up on a rack in order to force you to abandon them, and then to the gallows, so that they would not change their minds. Science does not stand still, and the rotation of the Earth around the Sun, and Newton's laws have become just special cases. It is likely that Einstein's general relativity expects the same.
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It depends on what ... You see, when it comes to energetic media in space, whether it is familiar matter or measuring the frequency of certain radiations coming from different angles to the observer, then this is a measurement relative to them, and not relative to the absolute system ... And as for her ... Then here - yes. In the theory of ether, we have a distortion of the lines, a change in the speed of processes and a certain maximum speed of propagation of signals, which together leads to the fact that a body moving relative to the ether not only does not feel its contraction, it also seems to it that EVEN RESTING relative to the ether body shrinks "according to Lorentz" in accordance with the same speed. In the theory of relativity, we initially assume that there is no absolute system at all, and all variations of the space-time parameters are only a consequence of invariance during transitions between inertial reference frames. A deeper analysis of the two theories continues to reveal the complete analogy of the mathematician of the two theories, which does not allow me personally to prefer either of them. Is that the theory of the ether seems a little more beautiful, since it has quite material analogies (the same experiments in liquid helium), and therefore does not require additional assumptions about operations directly with space-time coordinates.
In principle, the separation of theories is, of course, possible. But while the data are extremely vague and unreliable - the experiment with "superluminal" neutrinos require confirmation from other, independent laboratories, experiments on energy spectra will "creep" only at energies of the order of the Planck ones, to which even the LHC is like a vacuum cleaner to the LHC. No, gentlemen, that kefirshchik, that relativists - forgive me, while you for me are just one-figure interpreters of a single mathematical apparatus. It is, of course, interesting. But I'm glad that these are not my problems :)))
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So after all, in the theory of relativity, not everything is relative to each other. For example, it cannot be assumed that we are moving towards a ray of light at the speed of light, while it is standing still.
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Why? This moment is considered completely and exhaustively (for the theory of relativity, of course): if you move EXACTLY at the speed of light, then your time is worth, the speed of any processes in you for any external observer at a speed a little less - absolute zero and you NEVER, NOTHING you will not be able to determine. But if your speed is even slightly different from the speed of light, then the oncoming flow of even infrared radiation is hard ultraviolet for you, or even worse, and it falls on you exactly at the speed of light according to the principle of relativistic addition of speeds.
Just in case: in the theory of ether, if you move exactly at the speed of light, your particles do not exchange any signals at all (they simply do not have time to get from one particle to another, since the signals propagate in the ether with the speed "c", but the particles already move with speed "c"). Accordingly, the speed of any processes in you is zero, but this is only in the case of a homogeneous ether. In the presence of the characteristic Planck size of the discretization of the ether, you will not be able to come close to "c" at all: when the sizes of interparticle bonds in you are close to this scale, the nature of interactions will inevitably change, the spectra of atoms and molecules will "creep", which will most likely lead to their destruction and your death. But if you move away from the speed of light by at least a trillionth of a percent, you will see exactly the same as in the theory of relativity: the most severe ultraviolet, moving towards you at the same speed of light. Do not forget: you measure distances with curved rulers, measure time with lagging clocks and synchronize clocks, mark the rulers according to the same principle of emission-return of a light signal ... This is the sad truth.
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Finally!
It’s a pity that ignorant bawlers will run up anyway and will shout that all this experience is a complete hoax, does not prove anything and, in general, Einstein came up with his stupid theory only so that scientists could draw out more money from them, stupid ordinary people, or not give geniuses-nuggets of the fame they put for a drawing of a superluminal starship drawn with a curved pen. :)
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Exactly. This behavior is especially stupid, considering that even in the "theory of ether" the SRT formulas remain the same - there is a distortion of the size of bodies clearly "according to Einstein", depending on the speed, similarly, the intensity of any processes slows down, and also exactly according to the formula for slowing down time, and taking into account the fact that there is a limiting speed of signal propagation (in the theory of ether, the exchange principle of interaction with this speed is considered, due to which both length shortening and deceleration of processes are observed), the distance has to be measured by half the time of passage of the light beam "there -back". It is these three incidents: the distortion of the length, the change in the intensity of the processes ("curves" of the ruler, the lagging clock) and the forced method of determining the distances "in the light" and leads to the fact that from within the ether neither determine the zero, absolute frame of reference, nor detect the change in the speed itself light is not possible. This is how the relativistic principle of the addition of velocities operates, the effect of "mass increase" is observed (with reactive acceleration, for example, a system with automatically decelerating processes will never be able to exceed the speed of light - for an outside observer in an inertial system it will look like an effect of increasing mass, and also in absolute accordance with the formulas from the theory of relativity).
A funny incident, in fact. There is an almost complete coincidence of the mathematical basis of the two theories - however, supporters of one of them now and then appear against the evidence, trying to look for the same deviations in the speed of light. And this is even despite the fact that a number of effects from STR has been clearly demonstrated on the example of a quantum liquid - liquid helium! Lord kefirshchiki. Calm down and rejoice - the change in the speed of light cannot be detected even in your theory. And if the planet is unlucky enough to stumble upon an etheric stream, then it will simply be torn to shreds, and relativists will describe the phenomenon, before they die with everyone, as "a break in the metric of space-time in higher dimensions", and prove even in the hour of death who is right, all will fail equally.
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In fact, opponents of Einstein's general relativity also have a version that the light emitted by a moving source moves away from the source not with the addition of the speed of the source, but with the subtraction. That is, if the radiation source moves at a speed of 150,000 km / s, then the light emitted by it will move away from it at about the same speed, and not twice as high, as the respected master pointed out. It is precisely this circumstance that explains the example with double stars, without denying the absolute constancy of the speed of light. It would not hurt the author of the article to have less highly educated irony, since the truth only becomes the only true one when the failure of the others is proved. And with the refutation of this assumption, physicists have a complete collapse. Bye.
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I wonder how the source knows that it is moving at a speed of 150,000 km / s? To emit light "correctly"?
Let's launch two glass satellites in advance, along one line. One will move away 150,000 km / s, and the second will turn around and approach at the same speed. How fast will light move away from us?To answer
I am far from an expert in this matter. All my knowledge comes from popular science literature, so it's hard for me to judge who is more right. As for your question - "we", as I understand it, are in one of the glass satellites. Since the speed in the task is close to the light speed, it means that the time reference system is far from terrestrial, therefore the perceived speed of the surrounding objects does not fit into the terrestrial frame. It is also difficult to judge this, as if you try to observe from the side, at what speed the light is moving away from one satellite and at what speed it is approaching another. I think that the paradox of the passage of time did not allow Einstein to create a unified field theory.
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No, we are on Earth, from where we launch satellites and shine on them.
As you wrote at the beginning,
> the light emitted by a moving source moves away from the source not with the addition of the speed of the source, but with the subtraction
For a satellite flying towards, our source should emit light from 300,000 - 150,000 = 150,000 km / s
For a receding, apparently, 450,000 km / s (the satellite itself flies 150,000, and our light should overtake it at a speed of 300,000 km / s)
Such a contradiction arises with "subtraction", which is obvious even to a layman. It turns out that it is not the physicists who fail, but the opponents.To answer
Apparently, you inattentively read key phrases about another time frame.
About 25 years ago I was presented with a book by some foreign author about the theory of relativity and the life of Einstein with comments from foreign experts. To my great chagrin, I do not remember the author, and the book has long been lost. It describes the words of Einstein, how he came to understand the theory of relativity. He often thought what light is, because it corresponds to both the corpuscular theory (photons, elementary particles) and the wave theory - (the frequency of electromagnetic oscillations, the refraction of light). One day he thought what would happen if he rushed after a ray of light at the same speed and looked at the photons up close: what are they? And then he realized that this was not feasible, because the light would still move away from him at the same speed. The same book says that time in moving systems flows more slowly, inversely proportional to the speed of movement, remember the famous example with two twins, and when moving at light speed, the great master assumed (note: assumed, not claimed) that time stops completely. And in fact, the photon seems to be an eternal thing, outside of time, but it has a certain frequency of oscillations in a certain period of time, which is measurable. And now a little arithmetic: when moving at a speed of 150,000 km / s, time flows twice as slow, so you are moving at this speed, turn on the flashlight forward and a beam of light rushes away from you at a speed of 150,000 km / s. But for you, a second is two seconds for an outsider, motionless observer, i.e. we get the required 300,000 km / sec. Turn it back on and a ray of light will fly from you at the same - 150,000 km / sec - speed, since we minus your speed from the speed of light, and again we take into account a two-fold change in the flow of time, and "Oh, a miracle!" - again the same immutable 300,000 km / sec. By the way, it is clear to no specialist that 150,000 - 300,000 = -150,000. Such is the highest mathematics. And, like an ignorant bawker, I can add that all this experience is just another attempt to measure the speed of light (and with a very large error), since the rate of removal of the photon beam from the electron beam has not been measured in any way. Yes, and the speed of light itself cannot be measured, in nature there is no state of immobility: we move with the surface of the earth around the axis, the earth at this time - around the sun, it, in turn, around the center of the galaxy, which, according to the theory of the expanding universe, generally does not know where it is scratching ... So what is the speed of light? And about what?
Even the great Einstein (this is absolutely without any irony) doubted that time stops, why are we so self-confident?To answer
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This is again from the above book. Since physicists cannot instrumentally measure the change in time at relativistic velocities, measurements are taken from the red-violet shift of the spectrum. The general theory is broken down into several special theories, i.e. into several special cases (Einstein failed to create a unified field theory). In special theories, the change in space-time is considered in several parameters: the presence of a strong gravitational field, the movement of reference frames relative to each other, the rotation of the gravitational field, the movement of the reference frame in the direction of rotation or against it. Modern physicists can operate with speeds that are tens of thousands of times lower than the speed of light and measurements are carried out by indirect indications, but they are confirmed in practice, in particular, in the GPS system. The most accurate atomic clocks are installed on all satellites and they are constantly being corrected in accordance with the theory of relativity. In the light of this theory, physicists have developed about 30 different theories, the calculations for which are numerically comparable with the theory of Einstein. Several of these give more accurate measurements. Even Arthur Edington, without whose participation Einstein would not have taken place, in some places significantly corrected his friend. The theory I was talking about states that the speed of light is finite. But it can be slower. This is evidenced by a decrease in speed when passing through transparent media other than vacuum, and a decrease in speed when passing near strong sources of gravity. And the redshift itself is interpreted by some, not as a "Doppler effect", but as a decrease in the speed of light.
Not to be unfounded, quote:
The Hafele-Keating experiment is one of the tests of the theory of relativity that directly demonstrated the reality of the twin paradox. In October 1971, JC Hafele and Richard E. Keating took four sets of cesium atomic clocks aboard commercial airliners and flew twice around the world, first eastward, then westward, and then compared the "traveling" clocks with the clock remaining at the United States Naval Observatory.According to the special theory of relativity, the speed of the clock is greatest for the observer for whom they are at rest. In a frame of reference in which the clock is not at rest, it runs slower, and this effect is proportional to the square of the speed. In a frame of reference at rest relative to the center of the Earth, a clock on board an aircraft moving eastward (in the direction of the Earth's rotation) runs slower than a clock that remains on the surface, and a clock on board an aircraft moving in a westerly direction (against the rotation of the Earth) are going faster.
According to general relativity, another effect comes into play: a slight increase in gravitational potential with increasing altitude again speeds up the clock. Since the planes flew at approximately the same altitude in both directions, this effect has little effect on the difference in travel between the two "traveling" clocks, but it causes them to drift away from the clocks on the surface of the earth.
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What is it all about? - "and then compared the" traveling "watch with the watch remaining in the US Naval Observatory." Who was comparing? Who wrote the article? The one who flew the plane or the one who stayed on the ground? It's just that these comrades should have completely different results. If he was comparing the dude who stayed at the base, then Kitting's clock with Havel should have left for him. If, for example, Kitting was comparing, then the clock should have lagged behind at the base (and at Havel, too, even more). Well, in Havel's opinion, the clock lagged behind, on the contrary, Kitting's (and at the base, but less)).
Those:
- Havel will write Kitting's clock behind in his observation diary.
- Kitting will write "Havel's clock behind" in his diary.
- Kitting will look in Havel's diary and see "Kitting's clock has gone ahead."Those. since then, dude at the base, Kitting and Hafele will NEVER be able to pull ONE result because there are THREE of them! According to the number of observers-experimenters, respectively. And for each observer, his colleagues will confirm his personal result, which is different from others.
Well, I, as a reader of the article, get the fourth result, already relative to me. Accordingly, if Kitting and Havel moved relative to ME, the reader of the article, then their clock fell behind. And, accordingly, I will read about it in the article. In that article that only I and almost everyone else on Earth will see ...
But personally, neither Kitting nor Havel will ever know that they wrote it and what the inhabitants of the earth will see - they, personally, had completely different results ... And the publication about these results all over the world will be able to see 20 people. were on board with them ...
Here is a g ... it turns out according to your favorite theory. And how can you believe in this bogeyman? No wonder Einstein showed you the language ...
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Why fly anyway? Tickets for a business trip report can be obtained from arriving passengers near the baggage claim area.
I understand that you wanted to direct people to look for errors in reasoning. But nowadays the audience will simply assent "Einstein is a fool" and will not dig. It was necessary to make at least a hint about the non-inertia of all three frames of reference ...
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> We should have made at least a hint about the non-inertiality of all three frames of reference ...
Why should this "non-inertiality" somehow influence the results of this logical calculation of mine, what do you think? After all, the measurements by the authors of the experiment were carried out with "purely" non-inertial reference systems (there-ships departing-arriving aircraft, there-ships variable gravitational field, etc.). And this circumstance did not bother the authors at all - they measured, looked, announced - aha, it seems like there is a slowdown! After all, then it turns out that if they have this slowdown, then the wildness I described is reality? Or is there a third option?To answer
In which direction do you think Kitting was flying, and in which direction was Havel? Did you move along the ground at that time or did you remain motionless relative to the naval base with the reference clock? The correction made to the clock in the GPS system exceeds one second per month.
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Well ... I would not like to disappoint you, but in the consistently built theory of the ether, the same incident is observed: Petrov moves relative to Ivanov with a speed v, at time t = 0 they meet, at time (according to their own clock) t1 they send a request to a friend to each other, at the moment t2 they receive an answer about the readings of each other's clock. And what happens? And the fact that each of them will determine that the time of a work colleague Lags behind his personal, his own time. Moreover, it is by the value (1-vv / cc) to the 1/2 power. Similarly, with an attempt to determine the length - but two light signals are already needed there, to the beginning and end of the measured segment. By the way, simple school mathematics. I checked it myself at school.
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Explain, please, how these experiments can confirm or refute the second postulate of the SRT? How does the requirement for the inertia of the reference frame correlate with the accelerated motion of electrons?
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For that fought for it and ran...
arXiv: 1109.4897v1
Abstract: The OPERA neutrino experiment at the underground Gran Sasso Laboratory has measured the velocity of neutrinos from the CERN CNGS beam over a baseline of about 730 km with much higher accuracy than previous studies conducted with accelerator neutrinos. The measurement is based on high-statistics data taken by OPERA in the years 2009, 2010 and 2011. Dedicated upgrades of the CNGS timing system and of the OPERA detector, as well as a high precision geodesy campaign for the measurement of the neutrino baseline, allowed reaching comparable systematic and statistical accuracies. An early arrival time of CNGS muon neutrinos with respect to the one computed assuming the speed of light in vacuum of (60.7 \ pm 6.9 (stat.) \ Pm 7.4 (sys.)) Ns was measured. This anomaly corresponds to a relative difference of the muon neutrino velocity with respect to the speed of light (v-c) / c = (2.48 \ pm 0.28 (stat.) \ Pm 0.30 (sys.)) \ Times 10-5.
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Interesting ... MEASURING PARAMETERS OF EARTH AND SOLAR SYSTEM MOTION
(c) 2005, Professor E. I. Shtyrkov
Kazan Institute of Physics and Technology, KSC RAS, 420029,
Kazan, Siberian tract, 10/7, Russia, [email protected]
When tracking a geostationary satellite, the influence of the uniform motion of the Earth on the aberration of electromagnetic waves from a source installed on the satellite was found. At the same time, the parameters of the Earth's orbital motion were measured for the first time without the use of astronomical observations of the stars. The average annual speed of the found orbital component of motion turned out to be equal to 29.4 km / s, which practically coincides with the value of the Earth's orbital speed of 29.765 km / s known in astronomy. The parameters of the galactic motion of the solar system were also measured. The obtained values are: 270o - for the right ascension of the apex of the Sun (the value of 269.75o known in astronomy), 89.5o - for its declination (in astronomy 51.5o, and 600 km / s for the speed of the solar system. a uniformly moving laboratory coordinate system (in our case, the Earth) can actually be measured using a device in which the radiation source and the receiver are at rest relative to each other and to the same coordinate system. light from the movement of the observer.
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Thank you for a very interesting message. I immediately reread everything that came up on the topic of aberration. Therefore, it is now possible to determine the speed of the galaxy in accordance with the theory of the expansion of the universe. Or refute this theory.
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Perhaps it will be useful for you for reference (C) .... 1926 E. Hubble discovered that nearby galaxies statistically fit on the regression line, which in terms of the Doppler shift of the spectrum can be characterized by an almost constant parameter
H = VD / R,
where VD is the spectrum shift converted to the Doppler velocity, R is the distance from the Earth to the galaxy
In reality, E. Hubble himself did not assert the Doppler nature of these displacements, and the discoverer of “new and supernovae” stars Fritz Zwicky, back in 1929, linked these displacements with the loss of energy by light quanta at cosmogonic distances. Moreover, in 1936, on the basis of a study of the distribution of galaxies, E. Hubble came to the conclusion that it could not be explained by the Doppler effect.
However, the absurd prevailed. Galaxies with large redshifts are attributed to almost light speed in the direction from the Earth.
Analyzing the redshifts of various objects and calculating the “Hubble constant”, one can see that the closer the object is, the more this parameter differs from the asymptotic value of 73 km / (s Mps).
In reality, for each order of distances, there is its own value for this parameter. Taking the redshift from the nearest bright stars VD = 5, and dividing it by the standard relativistic value, we obtain the absurd distance to the nearest bright stars R = 5/73 = 68493
sorry to present the table here, I can’t))
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Regarding Ballistics and other things, I found in nete an interesting judgment on this topic ... The fact is that Galileo's deeply physical law of inertia says (in its modern formulation):
“Any physical body at rest or moving in a physical medium at a constant speed in a straight line or in a circle around the center of inertia will continue this movement forever, if other physical bodies or environment do not resist this movement. Such motion is motion by inertia ”,
Was transformed by Newton, 1687, into the wording:
"Corpus omne perseverare in statu suo quiescendi vel movendi uniformiter in directum, nisi quatenus illud a viribus impressis cogitur statum suum mutare"
"Every body continues to be held in its state of rest or uniform and rectilinear motion, as long as and insofar as it is compelled by the applied forces to change this state."
In its modern formulation, the so-called "Newton's first law" is even worse:
"Any material point maintains a state of rest or uniform and rectilinear motion until the impact from other bodies brings it out of this state."
At the same time, a purely experimental physical law found by Galileo in 1612-1638, perfected by 1644 by Rene Descartes and Christian Huygens, and widely known by the time of Isaac Newton's transition from alchemical to physical and mathematical activity, turned in the latter into philosophical nonsense - the movement of an abstract "Material" point in the void. 3 rotational degrees of freedom of motion by inertia and the medium - the carrier were excluded.
I understand how a modern person, in whose consciousness movement in emptiness was introduced at the level of instinct, dogmatic faith, it is difficult to realize the illogicality of this, the inconsistency of the Newtonian interpretation with the realities of Nature. However, without losing hope for understanding, I will try to convey my point of view to the reader.
If the movement of any physical system took place in an absolute (abstract) emptiness, then it would be impossible even logically to distinguish this movement from rest, since emptiness does not have distinctive features (marks) by which this movement could be determined. This “mathematical property” was used as a substantiation of relativism, although this “property” exists only in theory, in the minds of relativists, but not in Nature.
It should be noted here that Galileo's phenomenological principle of relativity, if not focusing on the trivial mathematical side - Cartesian transformation of coordinates, only asserts that at ordinary low speeds that people deal with in everyday life, the difference between inertial reference frames is not felt. For the etheric medium, these speeds are so negligible that physical phenomena proceed in the same way.
On the other hand, linear motion, measured in emptiness relative to other bodies, cannot be an objective unambiguous measure of motion, since it depends on the arbitrariness of the observer, that is, the choice of the frame of reference. In terms of linear motion, the speed of a stone lying on the ground can be considered equal to zero, if we take the Earth as the reference frame, and equal to 30 km / s, if we take the Sun as the reference frame.
The rotational motion, declared a special case and thrown out by Newton from the formulation of the law of inertia, in contrast to the translational motion, is absolute and unambiguous, since the Universe certainly does not revolve around any stone.
Thus, initially the purely phenomenological Galileo's law was cut off into three degrees of freedom, deprived of the physical environment and turned into a kind of abstract dogma that stopped the development of mechanics and physics as a whole, closing the thoughts of physicists only to linear relative motion.
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))) The reason for the movement or the opposite, in general, is a big mystery about the expansion ... here's to you from the apologist of etheric physics (c) ... Secondly, this is a mythical expansion of the Universe, contrary to facts and logic. In relation to what is the Universe expanding, where is the benchmark? Why is the paltry Earth a center of expansion? As the living classic of astrophysics, Dr. Arp, writes quite correctly, the redshift has nothing to do with the expansion of space or the "recession" of galaxies.
Third, in the actually observable Universe, we see objects much older than the age of the "Big Bang", for example, galactic clusters. Where did they come from? Wouldn't it be easier to ask yourself the question: where did the deceiver come from, composing fables about the "Big Bang"?
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> Why is the paltry Earth the center of expansion?
This center was given to you! Hubble's Law V = H * R (for Earth)
Take another point and recalculate the speeds for it, in a simple way, according to Galileo. The same will come out V1 = H * R1
And which one is the center?> The redshift has nothing to do with the expansion of space or the "recession" of galaxies.
Good. And what is it connected with?> Thirdly, in the actually observable universe, we see objects much older than the age of the "Big Bang", for example, galactic clusters.
How is their age assessed? Even Zeldovich simulated the gravitational compression of matter after the BW, and he quite got clusters (the so-called "pancakes")> where did the deceiver come from, composing fables about the "Big Bang"?
Lemaitre? From Charleroi. And what?To answer
Concerning Zeldovich and the cosmic microwave background It was theoretically predicted at the beginning of the twentieth century by the classics of physics Dmitry Ivanovich Mendeleev, Walter Nernst and others, and experimentally measured with high accuracy by prof. Erich Regener in 1933 (Stuttgart, Germany). Its 2.8 ° K result is practically indistinguishable from its current value. And the explanation of its origin of BV is not proof itself ... modeling, as practice shows)) ... is not the last resort due to its subjectivity in relation to the object ...
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Now the question is specific .... a) In the theory of relativity, the Doppler redshift is considered as a result of the slowing down of the flow of time in a moving frame of reference (the effect of the special theory of relativity). b) Hubble redshift is the result of dissipation of the energy of light quanta in the ether, its parameter “Hubble constant” changes depending on the temperature of the ether. Two mutually exclusive statements ... and the answer lies in one of them ...
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Temperature, ether? .... all that is known for certain is the cosmic microwave background temperature of 2.7ºK. And why should this temperature rise ...?! And if we talk about the etheric theory, it would be correct to speak not about the theory but about etheric hypotheses and theories .. Regarding the current state of temperature)) I hope that nothing has changed ... As for the time ... if you follow some hypotheses ... eternity)) in "both directions" ...
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> Temperature, ether?
I am just using your terminology:
"its parameter" Hubble constant "changes depending on the temperature of the ether"> And why should this temperature rise ...?!
Because "the Hubble redshift is the result of the dissipation of the energy of light quanta in the ether."
Energy is such a thing, it tends to persist. On this score, there is a sufficient number of phenomenological observations. And dissipation is not a loss of energy, but its transition into an indigestible form of chaotic motion, i.e. warmly. And if we have eternity in reserve (at least in one direction, backward), then the temperature of the ether should become infinitely high.To answer
That's what you mean ... this is a quote from the work ... I found in net)) ... "the Hubble constant changes depending on the temperature of the ether" ... in space, conditions arise for changing both the density and the temperature of the ether, these conditions are created by powerful radiation of stars .... and the temperature of the ether is constant at 2.723 ...))) never happens below. And dissipation in this matter is the absorption of energy by the ether, the ether in its turn gives its energy to the moving particles of matter, the more intense the faster the particle moves. Thus, stars containing masses of heated gas are absorbers of the ether energy, which is then emitted by them into space in the form of quanta of electromagnetic radiation.
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> the ether in turn gives its energy to the moving particles of matter,
> the more intense, the faster the particle moves
The effect would be noticeable in particle accelerators, for example, the LHC, which is not observed.To answer
)) And it is not surprising that it was "unnoticed" on existing accelerators, the opposite would be even more surprising, all this in fairness can be attributed to the Hicks boson. Even disregarding all subjective factors, the question arises whether it is generally possible from a technical point of view, hepothetical to detect that energy process with the help of accelerators and how to calculate it? After all, if you follow some ethereal theories ... the very phenomenon of gravity is the process of "circulation of energy in nature" between matter and not matter, or rather non-matter, that is, ether "...
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"Is it possible at all from a technical point of view, hepothetical to detect that energy process with the help of accelerators and how to calculate it?"
Elementary. Read the description of the accelerating sections of the collider in the section "Posters" by I. Ivanov, and you will immediately understand why it is easy.
Now, if they switch to laser overclocking methods, it will be possible to write off some interest there. But also not so much that due to this the stars shine.To answer
)) Is it possible that a way has been found to simultaneously measure the momentum and coordinates of a particle on accelerators, ... and without this, it is impossible to observe a similar process)) or its absence is impossible ... The Planck metric knows, sir ...
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It is enough to know the energy of the particle, and it is known quite accurately from calorimetric measurements. At a speed of ~ c, the process of transfer of ether energy will go a thousand times stronger than on the Sun.
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Nevertheless, I should explain the importance of the transfer of ether energies to matter within the framework of one of the ether theory ... as far as possible in this format ... The structure and parameters of the ether. Ether is a hierarchical structure consisting of corpuscular and phase ethers.
Elements of corpuscular ether are spherical particles of Planck radius 1.6 · 10-35 [m] and inertia numerically equal to the Planck mass 2.18 · 10-8 or, which is the same, Planck's energy 1.96 · 109 [J]. They are under the influence of a monstrous pressure of 2.1 · 1081. The array of particles of corpuscular aether integrally, that is statistically, is at rest and represents the main energy of the Universe with a density of 1.13 · 10113. The temperature of the corpuscular ether is absolutely constant 2.723 0K. It cannot be changed by anything.
The solar system moves relative to the corpuscular ether at the speed of Marinov (360 ± 30 km / s). This is observed as the anisotropy of the cosmic microwave background and the sidereal dependence of the speed of light, established by prof. Art. Marinov in 1974 - 1979. However, the microwave background is not a corpuscular ether radiation. This is the radiation of the "superstructure" over the corpuscular ether - the phase ether.
Phase aether consists of the same corpuscles (amers, in the terminology of Democritus) as corpuscular aether. The difference is in their phase state. If the corpuscular aether is a superfluid liquid, similar to solid helium, that is, in fact, a kind of quicksand without any friction between particles, then the mass of phase aether is like a saturated vapor interspersed into the mass of corpuscular aether.
The main part of the phase ether binds the corpuscular ether into etheric domains, the linear dimensions of which are 1021 times larger than the particles of the corpuscular ether. The particles of the bound phase ether are quasi-spherical mesh-string bags, each of which contains 1 ether domain of ~ 1063 particles of corpuscular ether. Etheric domains are empty blanks of elementary particles - electrons, protons, mesons ... They are seen by modern physicists as virtual particles, which, as it were, do not exist and which, as it were, exist at the same time.
When elementary particles are bombarded for a moment, particles of the phase ether that bind them are observed, which physicists consider quarks, attributing a fractional charge to them.
In the Universe, bound aether is 1063 times less than corpuscular, but 1063 times more than matter. The temperature of the bound ether is also constant and is in strict balance with the temperature of the corpuscular ether. The energy capacity of the bound ether ~ 3 · 1049 and its density ~ 3 · 1032 are also so high that its temperature and these parameters cannot be changed.
However, there is another type of ether - free phase ether, freely wandering through space (along the boundaries of ether domains), and accumulating in matter in a proportion of 5.1 · 1070, creating the phenomena of gravity and gravitational mass.
Gravity is the process of phase transition of this kind of ether into corpuscular ether, during which a gradient of ether pressure arises around the substance. This gradient is the force of gravity.
Being elementary electric dipoles, that is, “violators” of the pressure balance in the phase ether (at the boundary of the domains, which does not affect the pressure of the corpuscular ether), the amers of the phase ether are the cause of the occurrence of the phenomena of polarization (anisotropy of the distribution of dipoles), electric field and charges (pressure deviation in the phase ether up or down) and the electromagnetic field (light).
Since the energy density of free ether 2.54 · 1017 is not so high that it cannot be changed, and in some cases this change can actually be observed in the form of a change in the speed of light and redshift.
And following further, in the data coming from the detectors there is information about the transfer of energy by the ether to the substance, but it is impossible to isolate it at the moment ... this exchange is the very essence of the existence of matter, the presence of mass and motion, hepothetical in my opinion, of course ... If the details are inappropriate, then you can find it by scoring part of the text I am citing into a search engine. This is one of the works of Karim Khaidarov.
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> As the living classic of astrophysics, Dr.
> redshift has nothing to do with space expansion
> or the "scattering" of galaxies.
It's not a question. This statement. Having said "A", one must say "B" - what is the reason for the redshift then. I would like to hear.To answer
That is, there is no problem to simultaneously participate in several types of movement? And the reasons for this movement can be different? Then why attribute to a single star the motion _only_ as a result of the expansion of the universe?
Hubble constant ~ 70 km / s per _megaparsec_. Those. at the distance of the nearest stars, several parsecs, the expansion contribution is a million times less, of the order of 10 cm / sTo answer
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The experience of verifying the second postulate of SRT can not be complicated, but we can take and check an equivalent statement: in a transparent body, both in moving and at rest, the speed of light is the same and depends on the refractive index of the medium. Moreover, this has already been done by Armand Hippolyte Louis Fizeau, as reminded by E. Aleksandrov.
In the experiment of 1851, the light source was at rest, and the medium (water in parallel pipes) moved in opposite directions and along the way of the beam. And it turned out that the water seems to add some speed to the light in the case of a passing movement and takes away the same amount in the case of an oncoming one. But at the same time, the addition of the velocities of water and light turned out to be not classical: the experimental data were exactly two times less than those calculated according to Galileo's principle of relativity. At the same time, the predictions of the Fresnel theory (SRT prototype) differed from the measured values by 13%.
The intrigue is that any experiment of the Fizeau type (for example, multiparametric, when different fluids are involved in the experiment, different flow rates are used, and in a laboratory setup, the length of the pipes and the frequency of the light used) will give a result that is exactly half the calculated one according to the classical the law of addition of velocities. Why? Because the speed of light is not speed and adding it to the speed of water, for example, is not correct both metrologically and semantically. After all, speeds and their squares are defined in relation to different units of measurement. You can learn more about this by requesting links to "quad speed" in a search engine. We have the Earth, the orbital speed of which (30 km / s) is only an order of magnitude less than the speed of the thermal motion of the Sun's particles.
The sun receives and gives out 2e-5 W / kg (I will write in exponential notation, 3.14e + 2 = 3.14 × 10² = 314).
Then for the Earth it will be 1e-6 W / kg, i.e. every kilogram of terrestrial matter will receive 1e-6 J of kinetic energy every second.
All speeds are far from light, so purely school physics.
∆E = mV² / 2 - mV˳² / 2 = (m / 2) × (V²-V˳²) ≈ m × ∆V × V
∆V = ∆E / mV, m = 1kg V = 3e + 4 m / s ∆V≈3e-11 m / s per second
This, of course, is very small and completely imperceptible, but how many seconds do we have?
In a year, approximately 3e + 7, i.e. per year the speed will increase by 1e-3 m / s, by 1 mm / s
For a thousand years 1 m / s For a million 1 km / s For a billion years ...
Are you ready to join the Young Earth creationists? Me not.
Do these calculations cover the transfer of energy from the ether? No. But they set an upper bar for this transmission such that the weather does not make the etheric contribution to the heat release of the Sun.
We have to go back to fusion.
"And I think nuclear reactions are fundamentally unstable in the absence of artificial feedback, and once the reaction of the main substance of the sun had arisen, protium would not have occurred smoothly and stably, but would have exploded the sun like a hydrogen bomb."
First, there is a feedback, an explosion scatters the unreacted substance to the sides, reducing its concentration. Somewhere I came across a figure that about 10% of the plutonium reacts in a nuclear bomb. The infamous Chernobyl reactor exploded, but not in the same way as in Hiroshima.
Secondly, kinetics is a complex thing, and, for all its energetic benefits, some processes are going slowly. Otherwise, we would not be able to use metals in our oxygen atmosphere.
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Yes, it’s not worth it to waste time on trifles))) 30 km / s, ... and the galactic 220 km / s? Plus its own rotation around its own axis? My God, how much energy should be ... where is it ?! But I did not mention in the previous post about MASS and gravitating free phase ether, or gravity, according to you, does not require energy, so to speak, a "cost-free method" ?! corpuscular aether in this case, the phase transition occurs spherically symmetrically, the “collapse” of amers are compensated without producing Brownian motion of the particles.
As a result of this transformation, a spherically symmetric pressure difference is created around the gravitating substance, which determines the gradient of the gravitational field, and where there is force there is also energy ... So creationists can rest, although a couple of poultices)) should be placed. And I must say, for me personally, what was said above is still a hypothesis. Regarding the sun ... at one time it was assumed that the basis of nuclear fusion is the proton - a proton fusion reaction resulting in heavier chemical elements and the energy and duration of such a hypothetical combustion would be sufficient for 10 (tenth power) years of existence the sun, but the earth, terrestrial planets, asteroids have existed for 4.56 billion years and during this time the sun should have consumed up to half of its hydrogen, and research has confirmed that the chemical composition of the Sun and the interstellar medium is almost identical, and it turns out that for all time In the "burning" of the Sun, hydrogen was practically not consumed. And the neutrino flux does not come from the inner high-temperature parts of the Sun, but from the equatorial surface layers and is subject to seasonal fluctuations of daily, 27-day, annual, and 11-year fluctuations, and the neutrinos themselves are several times less than what is needed to state that the sun is present pp- reactions, a lot of questions in general .... З.Ы. There are more complicated and interesting questions. Advise where to ask them.To answer
Sorry,
Academician Aleksandrov for some reason in a million for the first time proved "the independence of the speed of light from the speed of the source."
And where is at least one single proof of the "independence of the speed of light from the speed of the receiver"?
The speed of a wave on the water does not depend on the speed of the wave source - a motorboat. But it DEPENDS on the speed of the receivers - the swimmers. A swimmer swimming towards the wave will register a wave speed greater than a swimmer swimming from the wave.
If the independence of the speed of the sea wave from the speed of the source does not prove the independence of the speed of the sea wave from the speed of the receiver, then the independence of the speed of the light wave from the speed of the source does not in any way prove the independence of the speed of the light wave from the speed of the receiver.
Therefore, Academician Aleksandrov really did not prove anything. What a pity.
And the existence of laser gyroscopes refutes the idea of the invariance of the speed of light. They really exist and really work. And they work on the principle of the difference in the speed of light for different receivers.
My condolences to the relativists.
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It seems to me that the speed of light is not constant. The constant is its increment, i.e. the value of the acceleration of the propagation of light in space, which is numerically equal to the Hubble constant, if in the dimension of the last megaparsec of the distance is converted into seconds of time and the numerical value of the constant is divided by the number of seconds in a megaparsec. In this case, Hubble's law will determine not the rate of removal of the extragalactic objects observed by us from the Earth, depending on the distance to these objects, expressed in the transit time of a light signal with a speed by us, the radiation left this or that object. See http://www.dmitrenkogg.narod.ru/effectd.pdf for details.
The speed of light is constant (for different ISOs) FOR ALL OTHER reasons.
The transition between the states of an abstract atom - from the "basic" state to the "glow" is characterized by a rearrangement of the atomic configuration. The elements of this configuration are massive, i.e. this transition takes time.
An abstract charge, as a component of this transition, has its own field. This field is not massive (inertialless), i.e. repeats the movement of its charge simultaneously with it in all space.
When the source atom and the receiver atom interact, the oscillations of the charge fields of the source atom act on the charges of the receiver atom instantly ("immediately"), regardless of the distance.
Those. The "speed of light" has two components - the infinite speed of the (field) interaction and the speed of transition of the receiver to the state of "glow".
In fact, this is a qualitatively completely different theory - field oscillatory.
In the general case, for the "constancy of the speed of light", an infinite speed of interaction is required.To answer
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Last spring, scientific and popular science magazines around the world reported sensational news. American physicists conducted a unique experiment: they managed to reduce the speed of light to 17 meters per second.
Everyone knows that light travels at a tremendous speed - almost 300 thousand kilometers per second. The exact value of its magnitude in vacuum = 299792458 m / s - a fundamental physical constant. According to the theory of relativity, this is the maximum possible signal transmission rate.
In any transparent medium, light travels more slowly. Its velocity v depends on the refractive index of the medium n: v = c / n. The refractive index of air - 1.0003, water - 1.33, various types of glass - from 1.5 to 1.8. Diamond has one of the highest values of the refractive index - 2.42. Thus, the speed of light in ordinary substances will decrease by no more than 2.5 times.
In early 1999, a group of physicists from the Rowland Institute for Scientific Research at Harvard University (Massachusetts, USA) and from Stanford University (California) investigated the macroscopic quantum effect - the so-called self-induced transparency, passing laser pulses through an opaque medium under normal conditions. This medium was sodium atoms in a special state called Bose-Einstein condensate. When irradiated with a laser pulse, it acquires optical properties that reduce the group velocity of the pulse by a factor of 20 million compared to the velocity in vacuum. The experimenters managed to bring the speed of light to 17 m / s!
Before describing the essence of this unique experiment, let us recall the meaning of some physical concepts.
Group speed. When light propagates in a medium, two speeds are distinguished - phase and group. The phase velocity vph characterizes the phase displacement of an ideal monochromatic wave - an infinite sinusoid of strictly one frequency and determines the direction of propagation of light. Phase velocity in the medium corresponds to the phase refractive index - the same, the values of which are measured for various substances. The phase refractive index, and hence the phase velocity, depend on the wavelength. This relationship is called variance; it leads, in particular, to the decomposition of white light passing through the prism into a spectrum.
But a real light wave consists of a set of waves of different frequencies, grouped in a certain spectral interval. Such a set is called a group of waves, a wave packet, or a light pulse. These waves propagate in a medium with different phase velocities due to dispersion. In this case, the impulse is stretched, and its shape changes. Therefore, to describe the motion of an impulse, a group of waves as a whole, the concept of group velocity is introduced. It makes sense only in the case of a narrow spectrum and in a medium with weak dispersion, when the difference in the phase velocities of the individual components is small. For a better understanding of the situation, a visual analogy can be made.
Let's imagine that seven athletes are lined up at the start line, dressed in multi-colored shirts according to the colors of the spectrum: red, orange, yellow, etc. At the signal of the starting pistol, they simultaneously start running, but the "red" athlete runs faster than the "orange" , "orange" is faster than "yellow", and so on, so that they stretch into a chain, the length of which increases continuously. Now imagine that we are looking at them from above from such a height that we cannot distinguish individual runners, but we just see a motley spot. Can we talk about the speed of movement of this spot as a whole? It is possible, but only if it is not very diffuse, when the difference in the speeds of the multicolored runners is small. Otherwise, the spot can stretch over the entire length of the track, and the question of its speed will be meaningless. This corresponds to a strong dispersion - a large spread of velocities. If runners are dressed in jerseys of almost the same color, differing only in shades (say, from dark red to light red), this will correspond to the case of a narrow spectrum. Then the speed of the runners will not differ much, the group will remain quite compact when moving and can be characterized by a well-defined value of speed, which is called the group.
Bose-Einstein statistics. This is one of the types of so-called quantum statistics - a theory that describes the state of systems containing a very large number of particles that obey the laws of quantum mechanics.
All particles - both enclosed in an atom and free - are divided into two classes. For one of them, the Pauli exclusion principle is valid, according to which there cannot be more than one particle at each energy level. Particles of this class are called fermions (these are electrons, protons and neutrons; this class also includes particles consisting of an odd number of fermions), and the law of their distribution is called Fermi-Dirac statistics. Particles of another class are called bosons and do not obey the Pauli principle: an unlimited number of bosons can accumulate at one energy level. In this case, one speaks of Bose-Einstein statistics. Bosons include photons, some short-lived elementary particles (for example, pi-mesons), and atoms consisting of an even number of fermions. At very low temperatures, bosons are collected at the lowest - ground - energy level; then the Bose-Einstein condensation is said to occur. Condensate atoms lose their individual properties, and several million of them begin to behave as a whole, their wave functions merge, and their behavior is described by one equation. This makes it possible to say that the atoms of the condensate have become coherent, like photons in laser radiation. Researchers at the US National Institute of Standards and Technology used this property of Bose-Einstein condensate to create an "atomic laser" (see Science and Life, No. 10, 1997).
Self-induced transparency. This is one of the effects of nonlinear optics - the optics of powerful light fields. It consists in the fact that a very short and powerful light pulse passes without attenuation through a medium that absorbs continuous radiation or long pulses: an opaque medium becomes transparent to it. Self-induced transparency is observed in rarefied gases with a pulse duration of the order of 10-7 - 10-8 s and in condensed media - less than 10-11 s. In this case, a delay occurs in the pulse - its group velocity is greatly reduced. This effect was first demonstrated by McCall and Hahn in 1967 on ruby at a temperature of 4 K. In 1970, delays corresponding to pulse velocities three orders of magnitude (1000 times) lower than the speed of light in vacuum were obtained in rubidium vapor.
Let us now turn to a unique experiment in 1999. It was carried out by Len Westergard Howe, Zachary Dutton, Cyrus Beruzi (Rowland Institute) and Steve Harris (Stanford University). They cooled a dense cloud of sodium atoms, held by a magnetic field, before their transition to the ground state - to the level with the lowest energy. In this case, only those atoms were isolated in which the magnetic dipole moment was directed opposite to the direction of the magnetic field. The researchers then cooled the cloud to a temperature of less than 435 nK (nanokelvin, i.e. 0.000000435 K, almost to absolute zero).
After that, the condensate was illuminated with a "binder beam" of linearly polarized laser light with a frequency corresponding to its weak excitation energy. The atoms moved to a higher energy level and stopped absorbing light. As a result, the condensate became transparent to the following laser radiation. And here very strange and unusual effects appeared. Measurements have shown that, under certain conditions, a pulse passing through a Bose-Einstein condensate experiences a delay corresponding to the slowing down of light by more than seven orders of magnitude - 20 million times. The speed of the light pulse slowed down to 17 m / s, and its length decreased several times - to 43 micrometers.
The researchers believe that by avoiding laser heating of the condensate, they will be able to slow down the light even more - perhaps to a speed of several centimeters per second.
A system with such unusual characteristics will allow one to study the quantum-optical properties of matter, as well as create various devices for quantum computers of the future, say, single-photon switches.
Regardless of color, wavelength, or energy, the speed at which light travels in a vacuum remains constant. It does not depend on location or directions in space and time
Nothing in the universe can travel faster than light in a vacuum. 299,792,458 meters per second. If it is a massive particle, it can only approach this speed, but not reach it; if it is a massless particle, it must always move at exactly this speed, if it happens in empty space. But how do we know this and what is the reason? This week our reader is asking us three questions related to the speed of light:
Why is the speed of light finite? Why is she exactly what she is? Why not faster and slower?
Until the 19th century, we did not even have confirmation of this data.
An illustration of light passing through a prism and splitting into crisp colors.
If light passes through water, a prism, or any other medium, it splits into different colors. Red refracts at a different angle than blue, which is what creates something like a rainbow. This can also be observed outside the visible spectrum; infrared and ultraviolet light behave the same way. This would only be possible if the speed of light in the medium is different for light of different wavelengths / energies. But in a vacuum, outside of any medium, any light moves with the same final speed.
The separation of light into colors occurs due to the different speeds of movement of light, depending on the wavelength, through the medium
This was only thought of in the middle of the 19th century, when physicist James Clerk Maxwell showed what light really is: an electromagnetic wave. Maxwell was the first to put the independent phenomena of electrostatics (static charges), electrodynamics (moving charges and currents), magnetostatics (constant magnetic fields) and magnetodynamics (induced currents and alternating magnetic fields) on a single, unified platform. The equations governing it - Maxwell's equations - allow one to calculate the answer to a seemingly simple question: what types of electric and magnetic fields can exist in empty space outside of electric or magnetic sources? Without charges and without currents, one could decide that there are none - but Maxwell's equations surprisingly prove the opposite.
Plate with Maxwell's equations on the back of his monument
Nothing is one possible solution; but something else is also possible - mutually perpendicular electric and magnetic fields oscillating in one phase. They have certain amplitudes. Their energy is determined by the frequency of field vibrations. They move at a certain speed, determined by two constants: ε 0 and µ 0. These constants determine the magnitude of the electrical and magnetic interactions in our universe. The resulting equation describes the wave. And, like any wave, it has a speed, 1 / √ε 0 µ 0, which turns out to be equal to c, the speed of light in vacuum.
Mutually perpendicular electric and magnetic fields oscillating in one phase, propagating at the speed of light, determine electromagnetic radiation
From a theoretical point of view, light is massless electromagnetic radiation. According to the laws of electromagnetism, it must move at a speed of 1 / √ε 0 µ 0, equal to c - regardless of its other properties (energy, momentum, wavelength). ε 0 can be measured by making and measuring a capacitor; µ 0 is precisely determined from the ampere, the unit of electric current, which gives us c. The same fundamental constant, first derived by Maxwell in 1865, has since appeared in many other places:
This is the speed of any massless particle or wave, including gravitational ones.
It is a fundamental constant that relates your movement in space to your movement in time in the theory of relativity.
And this is the fundamental constant that relates energy to rest mass, E = mc 2
Röhmer's observations provided us with the first measurements of the speed of light, obtained by using geometry and measuring the time required for light to travel a distance equal to the diameter of the Earth's orbit.
The first measurements of this quantity were made during astronomical observations. When Jupiter's moons enter and exit eclipsed, they appear to be visible or invisible from Earth in a sequence that depends on the speed of light. This led to the first quantitative measurement of c in the 17th century, which was defined as 2.2 × 10 8 m / s. The deflection of starlight - due to the movement of the star and the Earth on which the telescope is mounted - can also be estimated numerically. In 1729, this method of measuring c showed a value that differs from the modern one by only 1.4%. By the 1970s, s was determined to be 299,792,458 m / s with an error of only 0.0000002%, most of which stemmed from the impossibility of accurately determining the meter or second. By 1983, the second and the meter were redefined in terms of s and the universal properties of the radiation of the atom. Now the speed of light is exactly 299,792,458 m / s.
Atomic transition from 6S orbital, δf 1, determines meter, second and speed of light
So why is the speed of light no more and no less? The explanation is as simple as that shown in Fig. Above is an atom. Atomic transitions happen the way they do, because of the fundamental quantum properties of nature's building blocks. The interactions of the atomic nucleus with the electric and magnetic fields created by electrons and other parts of the atom lead to the fact that different energy levels are extremely close to each other, but still slightly different: this is called hyperfine splitting. In particular, the hyperfine structure transition frequency of cesium-133 emits light of a very specific frequency. The time it takes for 9 192 631 770 such cycles to pass determines the second; the distance that light travels during this time is equal to 299 792 458 meters; the speed with which this light propagates determines s.
A purple photon carries a million times more energy than a yellow one. The Fermi gamma-ray telescope does not show any delays of any of the photons that came to us from a gamma-ray burst, which confirms the constancy of the speed of light for all energies
To change this definition, something fundamentally different from its current nature needs to happen with this atomic transition or with the light coming from it. This example also teaches us a valuable lesson: if atomic physics and atomic transitions worked differently in the past or at long distances, it would be evidence of a change in the speed of light over time. So far, all our measurements only impose additional restrictions on the constancy of the speed of light, and these restrictions are very strict: the change does not exceed 7% of the current value over the past 13.7 billion years. If, according to any of these metrics, the speed of light was not constant, or it would be different for different types of light, this would lead to the largest scientific revolution since the time of Einstein. Instead, all the evidence speaks in favor of a universe in which all the laws of physics always, everywhere, in all directions, at all times remain the same, including the physics of light itself. In a sense, this is also quite revolutionary information.
Physics
Huygens' principle. The laws of refraction and reflection of light. Light dispersion
Wave nature of light and Huygens' principle.- Definitions:
- Wavefront - a surface that connects all points of a wave that are in the same phase (i.e. all points of a wave that are in the same state of oscillation at the same time);
- Ray - a line at each point perpendicular to the wave front and indicating the direction of wave propagation;
- Plane wave - such a wave, the wave front of which is a plane moving in space with the speed of the wave;
- For a spherical wave, the wavefront is a sphere, the radius of which is R = vt, where v- wave speed.
Based on this principle, it is easy to prove that light rays in a homogeneous medium propagate in a straight line.
Reflection of light based on wave theory. Let the plane wave fall at a certain angle a onto a reflective surface. By convention, the angle of incidence (as well as the angles of reflection and refraction) is referenced from the normal to the surface at the point of incidence.
1. The incident ray, the reflected ray and the normal to the surface at the point of incidence lie in the same plane;
2. Angle of incidence a equal to the angle of reflection g.
The speed of light in a vacuum and in a medium. The speed of light in a medium is less than the speed of light in a vacuum. It can be shown that in a vacuum
Where e 0 and m 0- dielectric and magnetic constants. If light propagates in a homogeneous medium with a dielectric constant e and magnetic permeability m, then the speed of light in such a medium is
(2.1)
Where n> 1 - absolute refractive index of the medium... In general, the speed of light depends on the properties of the medium, on its temperature and on the wavelength of light. Usually, the longer the wavelength of light, the faster it travels in a given environment, i.e. the speed of propagation of red light is greater than that of violet.
The relative refractive index of one medium 1 relative to another medium 2 is the ratio of the speeds of propagation of light in two media:
A medium with a high refractive index is called optically denser media, with a lower refractive index - optically less dense medium.
Refraction of light based on wave theory... The law of refraction of light during the transition from one medium to another with a different refractive index was discovered by Snell in 1620 and was first mentioned in the works of R. Descartes. This law can be derived using Huygens' principle.
Let a plane light wave fall at an angle a to the interface between two media with different speeds of light propagation in them. Then the following formula is valid for the angles of the incident and refracted rays:
(2.2)
Full internal reflection. If light passes from an optically denser medium to an optically less dense medium (for example, from a glass fiber into air), then the angle of refraction becomes greater than the angle of incidence. Since the angle of refraction cannot be greater p / 2, which corresponds to the angle of incidence
(limiting angle of total reflection),
Then all the rays of light falling on the interface between the media at angles greater a 0 are reflected back. This phenomenon is called total internal reflection.
Dispersion of light. The refractive index of any medium is determined by the properties of this medium and depends on the frequency (or wavelength) of light, i.e. n = n (w). The phenomenon of the dependence of the refractive index of a medium on the frequency of transmitted light is called variance.
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