The Davisson-Germer experiment is the classical experiment that verifies the formula of De Broglie: λ = h/mv


It is proposed here that a feasible modification in the original Davisson-Germer experiment could finally decide If Relativity Theory is right or wrong.

Detailed descriptions of the Davisson-Germer experiment can easily be found in the web

The original experiment uses the constant (“rest”) mass of the electrons and the classical formula for the Kinetic Energy in the applied formula. The classic magnitudes give exact results.

The electrons are accelerated by only 50 volts to reach velocities about 1% of the constant c. It must be considered that even at those velocities some mass variation should be detected but also it is easy to accelerate them more and precisely verify any dependency between the mass and the velocity of the electrons.


I can reasonably speculate why this experiment haven't been performed for higher velocities by both Relativity defenders or fighters to verify the if the mass of the electrons varies with velocity as sustained by Relativity or not? This is very strange!
Try to state that only the "rest mass" must be considering in the De Broglie formula is not aceptable. The original development of the formula determines that the "relativistic mass" must be used.

I sustain that the experiment at high velocities can give unexpected results, strange results that are not consistent with nothing and so there is no available information about this phenomenon.

I propose that the problem is the method used to deduce the velocity of the electrons. I propose that the problem is that the real Electrical Potential that acts on the electrons moving at high velocities is not the voltage between the accelerating plates and cannot be measured by a voltmeter!

I suggest to add a Velocity Selector in the Davisson-Germer apparatus just after the acceleration stage to measure the velocities directly.

A Velocity Selector is a stage were the electrons pass through both an Electric Field that produces a force to deflect them in one direction and a Magnetic Field that produces a force to deflect the electrons in the opposite direction. At the end of the stage there's a hole where only the electrons of a precise velocities can pass through. The Magnetic Force is velocity dependent and so the Electric Force can be adjusted to compensate the effect of the Electric Force. It's another method to mesure the velocity.

You may ask why I state that the Electrical Potential that acts on the electrons is not the voltage between the plates.
The answer is that I'm proposing new theories were the proper definition of the Electric and Magnetic fields are corrected by the factor "s". The new definitions predict that the Electric Potential that acts on charged particles at high velocities cannot be measured by a voltmeter!
I'm not suggesting here to analyze the new theories now! I just told how I arrived to the suggestion of a modified experiment.


There's nothing to loose and a lot to win performing the new version of the experiment. At least more precise results will be determined.

It's a very interesting idea to be consider by someones who have the resources to make a new apparatus and perform the suggested experiment.

I can't.


I just want to mention here that the new theories I propose predict that the mass will remain constant in spite of any variation in the velocity.

The Davisson-Germer experiment is the classical experiment that verifies the formula of De Broglie: λ = h/mv


It is proposed here that a feasible modification in the original Davisson-Germer experiment could finally decide If Relativity Theory is right or wrong.

Not that it will gain you any points but I like your suggestion regarding the test. It has been my contention that the proclaimed change in mass is based on mis-interpretation of the origin of momentum. That is I see the increased energy required to accelerate an object with relavistic velocity as being an energy transfer efficiency issue and not a mass change issue.

If applied energy is ineffective at acceleration and be becomes in affect stored in space chasing the object being acclerated then while trying to stop the object the energy catches up giving it more push; hence the apparent increased requirement for energy to accelerate as well as the increased momentum but without any actual change in mass.

The deflection in trajectory you propose should demonstrate the presence or absence of any actual change in mass. If I am correct the path it will follow will be that of its rest mass.

My view also accounts for the fact that "relavistic mass" does not reveal any gravity affects because it is not representative of any actual mass but simple energy transfer efficiency change.

The Davisson-Germer experiment.....I just want to mention here that the new theories I propose predict that the mass will remain constant in spite of any variation in the velocity.I only skimmed first part and then realized post is not worth reading because:
Because at least 50 years ago, following Lawrence's invention of the cyclotron, it was well established that an electron going around in a constant radius circle and gaining energy each time it crosses the cyclotron gaps requires a ever increasing magnetic field to keep it in that "constant radius circle." I like to say it is gaining relativistic mass and the force required to keep it on the constant curve qVB = ma, where a is the constant radial acceleration as electron is going around at speed V, essentially the speed of light so a = (V^2)/R = (c^2)/R, a constant. This means that the "m" in "ma" product is what is requiring the increase in B. (The electron charge, "q", the electric field, E, applied by the RF generator across the cyclotron gaps and the V =~ c are all constants so B ~ m.)

Fact is that B must be increased because the mass of the electron increases as relativity predicted, and was confirmed more than 50 years ago.

Two words of advice:

(1) Make predictions about the results of future experiments, not 50+ year old ones.

But if you insist on violating (1), at least:

(2) Do not predict the opposite of what has been observed.

:D

Two words of advice:

(1) Properly evaluate what prior testing has shown. An increased energy to retain a constant radius with increased velocity does not require nor indicate increased mass.


(2) The magnitude of deflection is a direct product of mass and its velocity. The test would indeed seperate the relavistic mass issue from mere mathematical projection into mathematical support or rejection.

(1) Propely evaluate what prior testing has shown. An increased energy to retain a constant radius with increased velocity does not require nor indicate increased mass.

Right. But in this case the increase in velocity is negligible, and Billy T explained so in his post, which you apparently didn't think to read. There is almost no speed increase very near the speed of light. Yet the strength of the magnetic field must grow disproportionately to keep the electron in orbit.

As an opponent of relativity theory, aren't you supposed to know these sort of things?

As an opponent of relativity theory, aren't you supposed to know these sort of things?

Before pooping off you might do well to have read my prior post. I don't see your post addressing or refuting the alternative view, of energy transfer efficiency change not mass change, in any way.

Here

It should also be noted that no self-respecting physicist today will advocate or support arguements for relavistic mass being actual mass.

Funny how you want to claim inertia in a cyclotron but disregard the absence of gravity associated with what you refer to as relavistic mass. :bugeye:

************************ Extract *************************
http://www.answers.com/topic/relativistic-mass

Some reasons for abandoning the notion relativistic mass:

One is forced to make statements like "A photon has no rest mass", which sounds slightly odd because a photon can never be at rest.

The idea of mass increasing with velocity leads many to believe that the internal structure of a quickly moving object is somehow altered. However, the standard view of relativity is that the internal structure of an object is always unchanged, and that the different quantities measured by different observers for energy and velocity are simply the same reality seen from different points of view.

The idea of relativistic mass combined with the notion of Lorentz contractions leads some people to the incorrect conclusion that an object traveling fast enough will form a black hole. However, by the very principle of relativity, if an object is not a black hole in one frame (its rest frame) it cannot be a black hole in any other frame either.

If one wishes to retain the notion that mass measures the "resistance" to acceleration, then mass can no longer be treated as a scalar quantity. This is because it is easier to accelerate something perpendicular to the direction of motion than parallel to the direction of motion. In effect, an object would have more mass in one direction than other.

The primary reason that most physicists chose to abandon relativistic mass in favor of the rest mass is that rest mass is a Lorentz invariant quantity — it is the same in every reference frame. Strictly speaking, it is the time-like component of a four-vector (the energy-momentum four-vector). A four-vector is a Lorentz invariant quantity, but its individual components are not.

In the end, the usage of mass, energy, and momentum in place of terms like rest mass and relativistic mass is a matter of semantics. Neither usage is technically wrong. However, that the latter terms are little used in the scientific community is a strong argument in favor of abandoning them altogether. Einstein himself wrote:

“It is not good to introduce the concept of the mass M = m/(1 - v2/c2)1/2 of a body for which no clear definition can be given. It is better to introduce no other mass than ‘the rest mass’ m. Instead of introducing M, it is better to mention the expression for the momentum and energy of a body in motion.” – Einstein, in a 1948 letter to Lincoln Barnett

This precisely echoes the modern sentiment.

However, in the “Autobiographical notes” by Einstein published in 1949,

“…the theory had to combine the following things:

1. From general considerations of special relativity theory it was clear that the inert mass of a physical system increases with the total energy (therefore, e.g., with the kinetic energy).

2. From the very accurate experiments… it was empirically known with very high accuracy that the gravitational mass of a body is exactly equal to its inert mass.”


Usage
"Relativistic mass" or velocity-dependent mass is still prevalent in popular books and some research papers:
************************************************** *******

From this we can assume you and Billy T are Popular Science Physicists?

I know about the "ciclotron experiment".
The problem is that it was bad interpreted.

The experiment demonstrates that the equation: qvB=kma is valid.
k is the "relativistic factor" (K=1/(sqr(1-v2/c2)))

The problem is that Relativity assume m'=km as a variable "relativistic mass" and is an error!
Actually the factor belongs to the other side of the equation which must assume the form: sqvB=ma
where s=sqr(1-v2/c2)
Then the factor determines that is the Magnetic field which has that variation with velocity and not the mass! Mass must be constant.
This is the interpretation I gve to the experiment in my new theory. and I sustain that there are many "old" well known important experiments that were (and are) bad interpreted! Particularly these:
_ "Strong magnet" experiment ("ciclotron experiment")
_ Kauffman
_ Hertz
_ Fizeau

Please take a look at: "A New Light In Physics" (http://www.geocities.com/anewlightinphysics)

...The magnitude of deflection is a direct product of mass and its velocity. The test would indeed separate the relativistic mass issue from mere mathematical projection into mathematical support or rejection.Not clear what you mean by "magnitude of deflection" - I spoke of a constant size circle and traveling at essentially the speed of light, say greater than 99.9999% of c. Thus, the radial acceleration (is this the "magnitude of deflection" you speak of?) is constant, but the force required to hold it to the same circle increase just as if you were swinging a bucket around your head with a rope and continuously adding water to the bucket by a fine hose strapped to the rope.

In both cases the reason more radial force is required to rotate the object at constant speed and constant radius is because that object is becoming more massive as its rotational energy is increased. Martilo's idea that this happens (or does not) because it depend on which side a factor is placed in some equation is just nonsense not worth a separate response.

We are speaking of physical effects and the only thing that is changing in the bucket at the end of the rope or in the cyclotron's charged particle is the rotating mass.

The problem is that it was bad interpreted.

The experiment demonstrates that the equation: qvB=kma is valid.
k is the "relativistic factor" (K=1/(sqr(1-v2/c2)))

The problem is that Relativity assume m'=km as a variable "relativistic mass" and is an error!
Actually the factor belongs to the other side of the equation which must assume the form: sqvB=ma
where s=sqr(1-v2/c2)I am too full of family and Christmas cheer to be negative today. So instead I will focus on the positive.

You are completely free to re-write the original equation in the form you desire. You can rearrange and solve as you wish, there is no requirement to leave the equation in its original form. What you did is simple algebra and is a perfectly valid way to write the original equation.

-Merry Christmas everyone!
Dale

And a Happy New Year.

You are completely free to re-write the original equation in the form you desire. You can rearrange and solve as you wish, there is no requirement to leave the equation in its original form. What you did is simple algebra and is a perfectly valid way to write the original equation.
True, and I can also associate the factor to the Magnetic Field and assume that is this that is affected by that factor and not the mass.
This is what I sustain.

Sure, no problem. However, you need to realize that you have not done any new theory here. You are not predicting any new results, so you cannot claim that relativity theory is wrong and you are right. You are just favoring a different interpretation of relativity, not making a new theory.

By the way, I think your interpretation is probably valid (and already understood) in the electron's frame. But I am not an expert. In any case, in our frame the magnetic field has one value so in our frame it must be the momentum that is increasing.

-Dale

>> that is the Magnetic field which has that variation with velocity...

Indeed all cosmic bodies show this is correct.... especially the planet Mercury.

Mass is indeed constant and that can only be determined when it is truly inertial mass.... ie in a circular orbit.

A relatively short time ago in these forums I proposed a science experiment and inquired whether it had ever been conducted. As usual, my truly innocent inquiry was met with a frenzy of absolute pro relativity vituperation.

To perhaps conclusively prove/disprove the relativistic increase of real mass:

In a particle accelerator having two parallel and seperate paths, we accelerate a positron and an electron in the same direction. Having achieved a high gamma, we then direct the two particles into a section where they may move sideways to make contact and annihilate.

WE ARE NOT MAKING THEM COLLIDE HEAD ON. ANYONE WISHING TO AGAIN ERRONEOUSLY REFER TO CERN, PLEASE FIRST LEARN WHAT YOU THINK YOU ARE TALKING ABOUT.

From the stationary laboratory frame of reference, the particles might have a large increase of real mass. From the laboratory frame of reference their sideways velocity at the moment of annihilation will be so low as to be negligible.

From the frame of reference of either of the two particles they have virtually no relative velocity with respect to each other and therefore virtually no increase of real mass and, in fact, virtually no kinetic energy.

Careful calorimetry can measure the annhilation energy release and provide proof/disproof of relativistic increase of real mass or relativistic increase of real kinetic energy or whatever way any relativity fan wishes to grammatically phrase it.

A little less than a century ago, for a few decades, there was strong belief that the relativistic mass increase was an increase of real mass and not a prestidigitation of kinetic energy. Upon the theorization and experimental disccovery of the positron, both the scienctific attitude and the laboratory means to do such an experiment existed. The experiment would not be a very expensive or complicated. I have been unable to find news of such an experiment ever having been performed.

My personal attitude is that science would genuinely benefit from either conclusive proof or disproof of Einstein relativity in its entirety so that it would not be possible for any thoughtful person to argue about it.

I do not have any bets riding on GR one way or the other.

Does anyone know if such an experiment has been conducted and what the outcome was?

In a particle accelerator having two parallel and seperate paths, we accelerate a positron and an electron in the same direction. Having achieved a high gamma, we then direct the two particles into a section where they may move sideways to make contact and annihilate.That is a much more interesting experiment than the original one proposed here. I would be surprised if it hadn't been done, since it seems pretty simple. I recall a quote by Einstein that he did not like the idea of relativistic mass, so I am not sure that the "no mass increase" result would really be a problem for SR.

What results would you expect in each case (relativistic mass increase or not)? I don't know enough SR to predict.

-Dale

...From the stationary laboratory frame of reference, the particles might have a large increase of real mass. ....From the frame of reference of either of the two particles they have virtually no relative velocity with respect to each other and therefore virtually no increase of real mass...

Careful calorimetry can measure the annhilation energy release and provide proof/disproof of relativistic increase of real mass or relativistic increase of real kinetic energy ....
Does anyone know if such an experiment has been conducted and what the outcome was?I hope someone else who is better versed than me will respond as this question shows some thought and appears sincere. However, it is not "an experiment" but two different experiments.

You did not tell which frame the calorimeter is in (the lab frame or co moving with the two particles). Probably because you do not realize it makes a difference, as I will try to show.

It is easy to tell what it measures in the second case: 2x511 Mev, or approximately 1 Gev. (if I am remembering the rest mass of an electron correctly)

In the lab frame, we would need many calorimeters, perhaps a collection of 100,000 thousand calorimeters, forming a long cylindrical tube, to have reasonable chance to catch the two annihilation gamma rays. One (the one with a direction component of its motion in the particle frame "forward") will be "blue shifted" in the lab frame and register more than an electron's rest mass energy in the calorimeter that absorbs it. (More that 0.511 Gev) and the other one will register less than 0.511 Gev. I think that the sum of these two will not be 2x511Mev, but may be wrong about this. Perhaps it is.

Here, without most of the math and surely not fully correct, is why I think this:
(1a)The Doppler shift (I think) at least for v << c is wavelength linear in v. by that I mean if v moves the source while the radiation is being produced by 20% of the wavelength in the direction the wave is being emitted then the free space wavelength is 20% less and thus the frequency is then 25% greater because (1/0.8) = 1.25
(2a)The energy of the photon is linear in the frequency so that "forward" photon would deposit 1.25 x 0.511 Mev in the calorimeter that caught it.
(1b) Now consider the "backward going" photon. Its new wavelength in the lab frame is 1.2 times normal and its frequency is 1/1.2 = 0.83333... of normal
92b) So its energy is 16.6666....% less than normal

A 25% increase in one and a 16.6666% decrease in the other do not compensate. That is the Lab frame calorimeters do measure an increase in energy over the 2x0.511Mev because in the lab frame more mass has been converted to energy.

This was to show, what I think is correct idea, but many details are wrong and I am too lazy to do it correctly, not even sure I could now.

Where is Pete when you need him?

BillyT:
Thank you for an interesting and expansive response.

I regret that you suffered complete confusion concerning the calorimeter frame of reference. I considered, though foolishly did not specify, a calorimeter at rest with reference to the laboratory. Of course, anyone with the means to accelerate a calorimeter to a high gamma ( once again foolishly not specified, but implied to be .99c or greater ) would be welcome to to do so if they desired.

You are already well aware that I am already well aware of the Einstein relativity difference between frames of reference, but, as usual are indulging in your predisposition.

My idea is: at a gamma of perhaps 10,000, we would measure a great difference in the energy liberated by annihilation if the liberated energy is based upon the validity of Einstein relativity or is not. This simple experiment would prove or disprove the validity with little room for further arguement. Even clumsy calorimetry can show the difference between one unit of energy and 10,000.

BillyT:
Thank you for an interesting and expansive response.

I regret that you suffered confusion concerning the calorimeter frame of reference. I considered, though foolishly did not specify, a calorimeter at rest with reference to the laboratory. Of course, anyone with the means to accelerate a calorimeter to a high gamma ( once again foolishly not specified, but implied to be .99c or greater ) would be welcome to to do so if they desired.I grew up in the hills of West Virginia. I saw may first calorimeter there at about age 12. It was a oxygen filled can with powdered coal in it, routinely used to evaluate the coal's heating ability. For me it was just sitting on the desk, but for my stellar friend it was traveling at the 0.99c you suggest. I thought the coal poor quality - it raised the temperature of the 500 gram mass by only 2.7 degrees. My stellar friend thought it excellent coal, if only a gram as I told him (we had measured it out earlier before evacuating and adding the oxygen.) and he agreed it produced a 2.7 degree temperature rise, but for him that was in 14.6 tons of calorimeter.

My point is that the results of the Calorimeter test, like any measurement of mass, will depend upon the frame in which the measurement is made. I don not think that either electrons or coal dust can be expected to show the same energy release (or mass) when they are gone if viewed from different frames.

This, of course, is the same train of thought that led to my question about Doppler shift of gravitons in the 'lab' frame. If the 'relativist mass'(kinetic energy) of a relativistic particle increases in the lab frame, why doesn't 'relativistic gravity' also increase with a mass approaching an observer and decrease with a mass receeding from the observer?

Next question. Is anyone here well-versed in Brans-Dicke theory? I do not know higher mathematics and am only very superficially knowledgable in the theory, so I don't know if I am intrepreting the theory correctly. Here goes.

Brans-Dicke theory contains a scalar-tensor field that allows for a 'variable' gravitational constant. Does the scalar-tensor also allow for a 'variable' mass in local space? I assume it may not, because Brans-Dicke is stated to be comparable to relativity theory at solar system distances.

Here is an interesting paper submitted by C. H. Brans on June 10, 2005, discussing the use of scalar fields in gravitational theory that I read for the first time last night. It gives a good insight about the theory and its equations.
http://www.arxiv.org/PS_cache/gr-qc/pdf/0506/0506063.pdf

...My idea is: at a gamma of perhaps 10,000, we would measure a great difference in the energy liberated by annihilation if the liberated energy is based upon the validity of Einstein relativity or is not. This simple experiment would prove or disprove the validity with little room for further arguement. Even clumsy calorimetry can show the difference between one unit of energy and 10,000.Let me suggest a slight modification or two to your experiment plan. (The budget is tight, so we can only afford one charged particle anyway.) The calorimeter is broken and we also lack funds to fix it, but the accelerator is fine. So I suggest we just accelerate the hell out of that charged particle and let is slam into some matter to see if it has more mass/energy, than Mo c^2 its constant mass kinetic energy ( I assume you do accept the fact that converting vanishing uranium mass in a nuclear reactor does produce energy in accord with E = Mc^2 so if it produces more than Mo C^2 you may accept that it had more than the rest mass Mo.)

Tough luck! - The accelerator is down for want of Liquid N2, which we can not afford also, but that smart young whiz kid we hired last week said:
“What about cosmic rays? They do your experiment for free, millions of time each minute.” He pointed out that many primary rays produce a million secondary rays also traveling at essentially c. The total KE of only a few of these secondary ray easily exceeds the KE of that primary, also traveling at c, if the rest mass is not greatly increased. Where did the energy of the secondaries come from if the primary only had the KE of a rest mass energy traveling at c? What do you think of his suggestion / comment - does it answer your question?

My idea is: at a gamma of perhaps 10,000, we would measure a great difference in the energy liberated by annihilation if the liberated energy is based upon the validity of Einstein relativity or is not.

I'll only point out that for gamma to = 10,000, v = 0.999999995c.

2Inq':
I did not intend to hijack your thread. I had an irresistable impulse to try to contribute to a sincere attempt to advance science.

I believe your concept and mine would potentially contribute to science if either or both were executed.

MacM:
I'll only point out that gamma=10,000 and higher has been published to have been already accomplished in particle accelerators.

BillyT:
You asked me if you answered my question.

I cannot imagine ever seriously needing for you to provide necessary information to me. I don't think I asked you a serious question.

MacM:
I'll only point out that it has already been published that gamma=10,000 and higher has been accomplished in particle accelerators.

I don't dispute that I was merely addressing your posting the 0.99c (or higher) statement along with the 10,000 gamma figure.

MacM:
Whatever.

Merry Christmas and Happy New Year.

2Inq':
I did not intend to hijack your thread. I had an irresistable impulse to try to contribute to a sincere attempt to advance science.

I believe your concept and mine would potentially contribute to science if either or both were executed.

Don't worry CANGUS, I don't consider it 'my thread'. I just proposed a question for discussion, or use, by anyone. I also am not trying to hijack your thread or idea, just discussing it. No discussion and threads quickly fall into obscurity on these forums.

Merry Christmas and Happy New Year.



Ditto. I'm googeling to see if I can find anything on your test.