# Does light have a mass?

Discussion in 'Physics & Math' started by GRO, Apr 6, 2002.

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1. ### thedIT GopherRegistered Senior Member

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Then you are talking about a nonexistent particle. A photon is the QM analog of an EM field or wave. It is what it is.

There is no particle rsponsible for charge, that we know of.

3. ### James RJust this guy, you know?Staff Member

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Tom:

Your equations have many errors. One thing you have completely failed to consider is the issue of momentum conservation in the collision between a photon and an electron.

IggDawg:

As I understand it, the Higgs boson (if it exists) does not couple to the photon. Hence the photon has zero rest mass.

5. ### Adam§Þ@ç€ MØnk€¥Registered Senior Member

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I thought the charge thing was a balance of properties of electrons and protons, opposites and all. Same as colour and spin are balances of properties between types of particles (or things).

7. ### thedIT GopherRegistered Senior Member

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This is one area of Physics that has yet to be explained.

An electron has -ve charge and as far as can be seen is a fundamental particle. That is, it is not made of other particles.

The proton has +ve charge but is made of 3 quarks each having +2/3rds or -1/3rd charge, the up and down quarks. This allows for combinations of,

+2/3+2/3-1/3 = 1 (A proton)

2/3-1/3-1/3 = 0 (a neutron)

These quarks have some different properties as well. They are not the reverse of electrons. (note to ongoing I think quarks are massless as well).

Wierd.

Anyway, time to get stuck on the M25.

8. James R,

As I stated in a previous post, the formulas I provided are messed up. I would try to post the correct formulas if it wasn't so hard to post formulas on sciforums.

My whole post was about the conservation of momentum. I tried to illustrate that the amount of momentum transfered from the photon to the electron decreases as the speed of the electron increases. This decreasing momentum transfer results in the decreasing acceleration of the electron, which gives the impression that the electron is gaining mass.

Tom

Last edited by a moderator: Apr 12, 2002
9. ### Adam§Þ@ç€ MØnk€¥Registered Senior Member

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I know that bit (not very well, but I've read it before), but what I thought was that +2/3+2/3-1/3 = 1 (A proton) = the opposite and balancing force to an electron, even if they are different and an electron is fundamental.

10. ### c'est moiall is energy and entropyRegistered Senior Member

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just a small interludium

Just took this small quote from Thed earlier:

"We know energy and mass are related via Einstein."

that's quite a popular misconception
see:

The "100 YEARS AGO" item in the 6 April 2000 issue of Nature (Vol. 404, p. 553) is taken from the 5 April 1900 issue of Nature (note the dates), and it states:

"The calculations of M. Henri Becquerel show that this energy is of the order of one ten-millionth of a watt per second. Hence a loss of weight of about a milligram in a thousand million years would suffice to account for the observed effects, assuming the energy of the radiation to be derived from the actual loss of material."

moreover, it was J.J. Thompson in 1881 who first developed the formula E=3/4mc2, and it was in a time when scientists still believed in aether
E=mc2 can even be derived from physics that is totally devoid of relativity theory, as even Einstein himself showed, with equations, in 1946

Last edited: Apr 12, 2002
11. ### c'est moiall is energy and entropyRegistered Senior Member

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quote from earlier

it seems that the experiment itself is the reason why ... that's not theory but it's UNDERSTANDING what you are doing, how you are doing it and why you are seeing what you see!

Last edited: Apr 12, 2002
12. ### thedIT GopherRegistered Senior Member

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1,105
Re: just a small interludium

OK, I was wrong, the idea was derived by others first, using classical physics as well. Unfortunately I don't know everything and have not read every paper ever written on the subject. As I said previously, I am not an authority as it takes a lifetime of study to fully understand these matters. My knowledge is usually enough to help others who have not studied this topic and are intersted.

That said, there is a difference between Einstein and the above. A very important difference to me. It is the use of the &gamma; factor, sqrt ( 1- (v^2/c^2 ). The above equations allow for arbitrily high velocities. Einsteins does not as the proper form is E( &gamma; ) = m( &gamma; ) c^2. Also, they, unless you now better than I, no one else derived the invariant form of relativistic kinetic energy, time dilation and such like. That is the big difference.

But isn't that the whole point. Theory predicts something, experiment confirms it. Most importantly, one experiment can contradict a theory. If Einstein was totally wrong then particles under the influence of constant force (electrical, magnetic or otherwise) would be able to exceed light speed. Nothing would stop them as the theory was wrong and another physics was oprerating. Hence we should see particles routinely exceeding light speed. That we do not implies Einstein was right.

Of all the expeiments and measurements done involving light, many thousands every month, surely some one, some where would have found the evidence by know. As has been stated, you win your name in science by overthrowing accepted wisdom, why do you think Einsteins name keeps popping up in theories. The lack of evidence of something violating Relativity speaks volumes.

NB: I know I posted a statement that some one may have that evidence. If proven true, kudos to them. If Einstein was wrong in some wierd way he could not have predicted, fine. That's the nature of how science works. Only a fool doggedly sticks to a theory in the light of evidence.

13. Thed,

". If Einstein was totally wrong then particles under the influence of constant force (electrical, magnetic or otherwise) would be able to exceed light speed. Nothing would stop them as the theory was wrong and another physics was oprerating. Hence we should see particles routinely exceeding light speed."

Imagine that you are in space. You have a gun in your hand, and your told to shoot an object(lets say it weighs a kilogram) floating in space, in the attempt to move it. You have an unlimmited amount of bullets and you can fire at the object as many times as you wish.What is the highest speed that object could reach???Could you make it go faster than your bullets???The answer is NO. The object might never reach the speed of the bullets. In this scenario, the speed of the bullets limit the maximum speed the object can reach.

From the example illustrated above, the same applies to subatomic particles. The maximum speed of a particle is dependent on the speed of the force pushing it. And as you know, the speed of the electromagnetic and gravitational interations are light speed. In other words, only if you push a particle with an electric, magnetic, or gravitational field for an INFINITE amount of time, could the particle reach the speed of the field(light speed).

Tom

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1,105
Tom

15. ### c'est moiall is energy and entropyRegistered Senior Member

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"In other words, only if you push a particle with an electric, magnetic, or gravitational field for an INFINITE amount of time, could the particle reach the speed of the field(light speed). "

I don't think so
time doesn't matter
I don't know if that was what Thed meant ...

16. ### ImaHamster2Registered Senior Member

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220
Trying to understand Non-Einstein physics…

Ah…but how fast could the guy shooting the bullets go?

Say you’ve sped up a particle to close to the speed of light and then the particle spontaneously emits something backwards. Is that backward emission also limited by the speed of light? If so what about a similar emission in the forward direction? Would there be the same change in particle momentum from a backwards emission as from a forward emission?

How would the particle speed change in each case and why?

C'est moi, Tom? What would be the non-Relativity explanation?

17. ### c'est moiall is energy and entropyRegistered Senior Member

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"K, I was wrong, the idea was derived by others first, using classical physics as well. Unfortunately I don't know everything and have not read every paper ever written on the subject. As I said previously, ..................................."

I did not meant to push you in a corner or something. You know much more about physics than I do. I just feel that some things are often wrongly attributed to Einstein.

"That said, there is a difference between Einstein and the above."

Of course there is! It's the idea that counts (btw, Thompson was not way off!!!)

"no one else derived the invariant form of relativistic kinetic energy, time dilation and such like. That is the big difference."

time dilation --> Lorentz transformations no??

"But isn't that the whole point. Theory predicts something, experiment confirms it. Most importantly, one experiment can contradict a theory. If Einstein was totally wrong then particles under the influence of constant force (electrical, magnetic or otherwise) would be able to exceed light speed."

I think you keep missing/avoiding the point and I won't repeat it cause I've repeated it three to four times. Think about your last sentence one more time ... spot the reason why it doesn't happen (but it can!! -> see future experiments, if not then be it so, it is not a requirement).

"Hence we should see particles routinely exceeding light speed. That we do not implies Einstein was right."

maybe I should also remind you and others that it was Point Carré who stated years before Einstein, without any proof, the constant speed of light in all FOR (the two never had a good relationship after Einstein published his paper in 1905 without any mention of Carré nor Lorentz)

"The lack of evidence of something violating Relativity speaks volumes."

--> see controversion on Michelson-Morely exp. and their null result
--> see controversion on existance of neutrino's
--> see the huge energy loss from proton-proton annihilation that Special Relativity cannot explain with the neutrino
--> Completely fails to explain the observed Binary Star precession (for example: In Binary Pulsar PSR J1518+4904, the observed value is 3959" and the value calculated by GR is 5640 or 11280 using the to Star's masses... many more can be given)
--> Cannot explain the experimental results of muon decay without resorting to neutrinos
--> compton effect: Experimental results with a difference of about 2 %
--> cannot explain electrons traversing absorbers (disappeared completely out of literature, neutrino cannot be used)
--> the velocity sum equation doesn't conserve energy and momentum, when compared with the calculation using SR's Kinetic Energy and momentum equations
--> the General Theory of Relativity yields an equation that explains the Mercury perihelion advance, it is also well known that this equation cannot explain either the Venus, Earth and Mars perihelion advance
--> Cannot explain LMT (Linear momentum transfer in nucleus-nucleus collision), issue disappeared from the literature with no explanation

There seems to be something. You do have to open your eyes for it. Other people far more knowledgable in this will be able to cite more than me. besides it's 2:55 am here and i really have to go to bed now!

18. ImaHamster2,

I'm not sure.

It's one thing to describe the effects of one particle on another in the case that both particles remain intact, but it's quite another thing to describe what happens when one particle emits another particle.

The Hamster seems to be asking questions that probably most scientists can't answer.

Basically, I would have to understand the properties of the emitting particle and the emitted particle before I even try to come up with an answer.

Tom

19. ### James RJust this guy, you know?Staff Member

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37,766
Here's a problem with the bullet theory:

Let's say you're shooting a rock to make it move faster (in space, say). The bullets have velocity v. c'est moi and others say that therefore the fastest you can make the rock go is v. Now, consider the case where I move in the same direction as the rock with speed w. Then, I suppose you will agree that I can now get the rock to go at speed v+w with my bullets.

Applying the same argument to light, if I use light (or any electromagnetic field) to accelerate an electron (for example), then I will only be able to accelerate it to the speed of light. Now, if the accelerating source is also moving, we should be able to accelerate the electron to a speed faster than the "stationary" speed of light.

Are there any moving particle accelerators? Answer: Yes. Electromagnetic fields of things like stars and quasars can accelerate electrons, and the stars and quasars are observed to move, sometimes at large fractions of the speed of light. But <b>we never see any particles travelling faster than the speed of light</b>. Relativity explains why. c'est moi's theory doesn't.
--------------

In response to c'est moi:

Aside: It's <b>Poincare</b> (with an acute).

<i>--> see controversion on existance of neutrino's</i>

What? Neutrinos undoubtedly exist.

<i>--> see the huge energy loss from proton-proton annihilation that Special Relativity cannot explain with the neutrino</i>

<i>--> Completely fails to explain the observed Binary Star precession (for example: In Binary Pulsar PSR J1518+4904, the observed value is 3959" and the value calculated by GR is 5640 or 11280 using the to Star's masses... many more can be given)</i>

<i>--> Cannot explain the experimental results of muon decay without resorting to neutrinos</i>

So?

<i>--> compton effect: Experimental results with a difference of about 2 %</i>

References. Explanation.

<i>--> cannot explain electrons traversing absorbers (disappeared completely out of literature, neutrino cannot be used)</i>

What?

<i>--> the velocity sum equation doesn't conserve energy and momentum, when compared with the calculation using SR's Kinetic Energy and momentum equations</i>

This is just plain wrong.

<i>--> the General Theory of Relativity yields an equation that explains the Mercury perihelion advance, it is also well known that this equation cannot explain either the Venus, Earth and Mars perihelion advance</i>

This is wrong too.

20. James R,

"Let's say you're shooting a rock to make it move faster (in space, say). The bullets have velocity v. c'est moi and others say that therefore the fastest you can make the rock go is v. Now, consider the case where I move in the same direction as the rock with speed w. Then, I suppose you will agree that I can now get the rock to go at speed v+w with my bullets."

You're absolutly correct, the final speed is v+w, unless v+w is greater than light speed.

Let me remind you, c appears to be the maximum speed in the universe. Nobody knows why this is the case.

In other words, photons will always be emmited at light speed regardless of the speed of the emmiting particle. Photons have some internal source of acceleration: If a photon is traveling below c, it attempts to speed up to c, and if the photon travels faster than c(if it is possible), it attempts to slow down to c.

Tom

21. ### c'est moiall is energy and entropyRegistered Senior Member

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"Aside: It's Poincare (with an acute). "

yes i know that's a silly fault

"--> see controversion on existance of neutrino's

What? Neutrinos undoubtedly exist."

no they don't
the neutrino was postulated in order to save SR's inability to explain energy and momentum conservation in the historic RaE experiments
I hear thousands of times: The Neutrino exists
The construction of detectors such as Super-Kamiokande are designed to detect Neutrinos from the Sun because they exist there...... they didn't construct the detector to try to detect something "postulated as hypothesis" due to the SR equation's failure to explain energy conservation, as a truly scientific endeavor should say it!!

Super-K's Published Paper can be found at http://xxx.lanl.gov if you want to follow next issue

To obtain some of the data used in their paper, the author's' needed to "detect' the Neutrino flux and herein lies the first failure: They only "detected" 38% (a 263 % smaller than expected) of the Solar Neutrino flux predicted. This is not always true with other detectors. Some times they "detect" more Neutrinos, some time less, depending on "special Neutrinos" or Neutrinos emitted by different atomic reactions. But the average always is around 1/3 of the predicted flux ii.

The second failure, though small, is the daytime flux compared with the nighttime flux. At least the nighttime flux should be equal to the daytime flux, or slightly less. But here the contrary happens.

The nighttime flux is 2 % larger than the daytime flux.

Looking at Fig 3 in the original paper, the numbers of events don't follow the annual variation due to the Earth's eccentricity. It is the contrary. This means that when the Earth is far away from the Sun, the measured flux is larger - even though it should be smaller.

The expected variation is 7% maximum and the measured variation is 26 % maximum, that is 370 % larger. They don't say this very clearly for tell the truth, would be to admit failure.

The first failure, the 1/3 value (263 % smaller) for Neutrinos detected, and the other failure, the 26% (370 % larger) of variation due to eccentricity are the most glaring failures in the paper up to this point. But they don't stop here.

They say clearly: "One obtains a clear peak from the solar neutrinos". this curve as it is plotted in their paper is misleading the reader or observer

analyze a wide angular interval at two different positions and suppose that 37 degrees is the interval where the signal event is coming from the Sun. This is not technically true, but we want to clearly show that even taking a wide theta angle there is more signal events when this same angle (37o), or interval, is taken close to 90o.

Counting, the events from theta = 0 to theta 37 degree (cos q = .8) we have the following sum: 0.24 + 0.179 + 0.163 + 0.134 + 0.132 + 0.118 + 0.112 + 0.105 = 1.183 event/day.

Taking the same interval of 37 degrees from theta = 60 degrees to theta = 97 degrees we count 27 events. The average of the values is 0.095 and 27 x 0.095 = 2.565, that is, 2.565/1.183 = 2.17 times the value in the first interval, which "correspond to the Sun direction." That is to say, the interval between theta = 60 degrees and theta = 97 degrees contains 2.17 times more events than the interval between theta = 0 degrees (cos theta = 1) and theta = 37 degrees (cos theta = 0.8). We mention the last interval as the "Sun direction," evidently a very wide interval!

make a curve of this and do you see the peak favoring the Sun direction?? It is the contrary ;in ONE day there are more events in many other directions than from the Sun direction!!!

What the Sun direction means? What is the angle "defined" as the Sun direction? 37 degrees, 26 degrees or less? Technically is theta = 0 but there, there are no events, and consequently the argument above makes sense.

the claimed 0.24 event/day only represent 3.16 % of all event/day which itself is 96.84 %. Taking 0.6 event/day with 8% and 92 %, we arrive to the same conclusion.

If Super-Kamiokande could show that 50, 60 or 70 % - equivalent to 3.8, 4.565 or 5.32 event/day - of the entirety of events come from the Sun direction, we could be convinced that Neutrinos from the Sun were being detected. The values of 3.16 %, or 8 %, do not support any positive conclusion
the neutrino remains a phantasy implied by relativity
if you think otherwise, then be it so

22. ### c'est moiall is energy and entropyRegistered Senior Member

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"--> see the huge energy loss from proton-proton annihilation that Special Relativity cannot explain with the neutrino

please explain how SR explains it ...

look, the two jets in opposite directions conserve momentum. Labeling the particles as muons, electrons, kaons, etc., the energy calculated with SR is between 1/4 or 1/5 of the protons' colliding energy --> see: G. Arnison et al., Phys. Lett. 123B, 115(1983). M. Banner et al., Phys. Lett. 118B, 203(1982).

"--> Completely fails to explain the observed Binary Star precession (for example: In Binary Pulsar PSR J1518+4904, the observed value is 3959" and the value calculated by GR is 5640 or 11280 using the to Star's masses... many more can be given)

you need another example?

DI Herculis binary Star has an observed value of 2340" and the GR equation gives 8423" failing by 3.6 times. Taking the sum of the two Stars' masses, as should be done, the value is 17977"

look here:

F. Guinan, J. J. Marshall and F. P. Maloney, Dep. of Astrophysics, Villanova University, Villanova, PA 19085, USA, from "Commission 27 and 42 of the AU Information Bulletin on Variables Stars."

4 Number 4101, Kenkeley Observatory, Budapest, October 12, 1994

P Guinan and F. P. Maloney, Astron. J., 90, 1519(1985).
Binary Pulsar PSR J1518+4904: Orbital Precession and Mass Estimates. D. J. Nice(NRAO), R. W. Sayer, J. H. Taylor (Princeton)

"--> Cannot explain the experimental results of muon decay without resorting to neutrinos

So? "

sidenote: there is no such thing as a neutrino

"--> compton effect: Experimental results with a difference of about 2 %

References. Explanation. "

see here for full explanation http://www.autodynamics.org/Experiments/ComptEff.html

"--> cannot explain electrons traversing absorbers (disappeared completely out of literature, neutrino cannot be used)

What? "

SR needs neutrino to explain this phenomenon (again).
BUT, cannot use it because Buechner and Van de Graaff demonstrated overwhelmingly that the electron-neutrino doesn't exist

"--> the velocity sum equation doesn't conserve energy and momentum, when compared with the calculation using SR's Kinetic Energy and momentum equations

This is just plain wrong. "

because you are ignorant of this problem:

Example:

mv = 600 MeV

KE1 = 50 MeV

2 = 0.75 c

B1 = 0.399 652

B2 = 0.75

B3 = 0.795 222 824

Velocity SUM: Bs = 0.884 525 (should be 0.791 971)

The velocities are different. Energy and momentum are not conserved.

"--> the General Theory of Relativity yields an equation that explains the Mercury perihelion advance, it is also well known that this equation cannot explain either the Venus, Earth and Mars perihelion advance

This is wrong too."

no it is true

23. ### c'est moiall is energy and entropyRegistered Senior Member

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"Applying the same argument to light, if I use light (or any electromagnetic field) to accelerate an electron (for example), then I will only be able to accelerate it to the speed of light. Now, if the accelerating source is also moving, we should be able to accelerate the electron to a speed faster than the "stationary" speed of light. "

hum, is this an argument? bullets and light cannot be compared
I have never argued that light speed is not constant
I see no further thing to reply to this
I think I am still correct