If there is no Ether how can we talk about light being a wave?

  • Thread starter Thread starter protonman
  • Start date Start date
  • Tags Tags
    Ether Light Wave
  • #51
Originally posted by Hurkyl
Prove they're an idiot.
Because based on unsubstantiated statements on the internet the teacher suggested that I be reported to the school. This is a person who doesn't think. You call me a bad teacher look at this persons advice.
 
Physics news on Phys.org
  • #52
Originally posted by Deeviant
I know were all having fun laughing at protonboys trolling, but could we get to the banning the flaming troll part already?
I don't know why everytime I make an agrument that can't be refuted or you just don't understand it is called trolling. If you understood my comments and arguments you would see that it is not trolling. But, because you can't see the logic and connection between what I say and the topic you need to call me a troll.

I know what you are going to say now. How I have shown no logic and there no connection. This, of course, will be merely stated without any actual evidence or a particular case. Only after my repeated requests for a evidence will an attempt be made to prove you point. Then I will easily refute you trite argument and the process will start all over again. This is so predictable. With the exception of David all of you follow the exact same pattern. You are so predictable. Maybe I should publish a theory. The experimental evidence is overwhelming.
 
  • #53
Originally posted by ahrkron
Am I doing any statement about what the Bible should say?
Not quite sure what this means. Is this English?
 
  • #54
protonman: I have the degrees to back up what I say. I am a physics teacher. Unlike you people, I teach students how to think not what to think.

protonman: By definition it [a wave] is the the vertical oscilatory motion of a medium. The 'wave' itself is nothing more than the motion of the medium. It is not some independent physical entity. Without a medium it is nonsense to talk about a wave.

Nereid: please tell me the name of a physics textbook which provides a definition of a wave like the one you gave, and explains sound and light (or electromagnetic waves in general) in terms of the words in your definition.
Please tell me the name of the physics textbook (or textbooks) that you use to teach physics, especially the part about waves.
 
  • #55
protonman: I don't know why everytime I make an agrument [sic] that can't be refuted or you just don't understand *SNIP
What is your argument?
protonman: Only after my repeated requests for a evidence will an attempt be made to prove you point. *SNIP
What evidence have you requested?
protonman: Maybe I should publish a theory. The experimental evidence is overwhelming.

Nereid: protonman, and David,

Are there any experiments or observations that you are aware of which are inconsistent with either SR or GR? Same question, expressed slightly differently: what predictions of SR or GR are you aware of which have been shown to be wrong by experiment or observation?

If you have alternative theories/ideas/hypotheses with a similar or overlapping scope to SR or GR, what concrete predictions can you make from these? Specifically, what do you predict that is different from SR or GR? I'm interested, at this stage, in any differences at all, whether they are measurable by current instruments (or technology) or not.[/color]


protonman's reply: I don't accept your methods.
I don't know why everytime I ask a question about something I don't understand in what you write you ignore me or call me an idiot. If you were a real physics teacher you would see that you are being inconsistent. But, because you can see the logic and connection between what you say and the topic you must be a troll.

I know what you are going to say now. How I have shown no logic and there no connection. This, of course, will be merely stated without any actual evidence or a particular case. Only after my repeated requests for a evidence will an attempt be made to prove your[/color] point. Then I will easily refute your[/color] trite argument and the process will start all over again. This is so predictable. Y[/color]ou follow the exact same pattern. You are so predictable. Maybe I should publish a theory. The experimental evidence is overwhelming.
 
  • #56
Originally posted by Nereid
Please tell me the name of the physics textbook (or textbooks) that you use to teach physics, especially the part about waves.
If you don't like the definition refute it on its own merits. Not on what book it came from.
 
  • #57
Originally posted by protonman
I don't know why everytime I make an agrument that can't be refuted or you just don't understand it is called trolling. If you understood my comments and arguments you would see that it is not trolling. But, because you can't see the logic and connection between what I say and the topic you need to call me a troll.

I know what you are going to say now. How I have shown no logic and there no connection. This, of course, will be merely stated without any actual evidence or a particular case. Only after my repeated requests for a evidence will an attempt be made to prove you point. Then I will easily refute you trite argument and the process will start all over again. This is so predictable. With the exception of David all of you follow the exact same pattern. You are so predictable. Maybe I should publish a theory. The experimental evidence is overwhelming.


If it was just me saying your a troll, then you might have a case. If two people say your a troll, you'd be losing ground. If nearly everybody on the board agrees your a troll, then it is more than likely true.

And I would really like to know which publication you intend to publish your story on. It would be interesting to measure how quickly they reject your "theory" and cite it as "meaningless babble".

If being different and thinking "outside the box" means being disrespectful, brash, and wrong, then I would rather be one of the nameless majority.
 
  • #58
Taking candy from a baby man...

Originally posted by Deeviant
If it was just me saying your a troll, then you might have a case. If two people say your a troll, you'd be losing ground. If nearly everybody on the board agrees your a troll, then it is more than likely true.
Most people believed the Earth was flat at one time. Does this mean it was most likely true?

And I would really like to know which publication you intend to publish your story on. It would be interesting to measure how quickly they reject your "theory" and cite it as "meaningless babble".
Same one all you people publish in "The Journal of Blatantly Obvious"
If being different and thinking "outside the box" means being disrespectful, brash, and wrong, then I would rather be one of the nameless majority.
Again show me where I am wrong. P.S. please provide evidence.
 
  • #59
Originally posted by protonman
Taking candy from a baby man...

Most people believed the Earth was flat at one time. Does this mean it was most likely true?

Same one all you people publish in "The Journal of Blatantly Obvious"
Again show me where I am wrong. P.S. please provide evidence.

Unfortunely for you, this is not the old world. Many of the people on this board, and I'm sure all of the mentors have a very solid grip on the Scientific Method. Having agreement between a large and varied body of scientists(doesn't get much more diverse then a internet forum like this) is how science puts forth actual results nowadays. Upon looking at the history of your posts, it is obvious why you referenced old world mentality: You sir, are stil living in the old world, at least when it comes to your science.


I do agree with you about something however:
I would publish the fact that you are full of crap and produce nothing except for meaningless babble in "The Journal of Blatantly Obvious."

I would provide evidence of your wrongness, but for the life of me I can't figure out what the hell you are actually trying to say and in fact I would bet you don't even know what the hell you are trying to say. It seems that you never actually say anything, you just provide a never ending stream insulting commentary( A definitive mark of a forum troll).


What exactely makes you think insulting people has anything to do with science? Perhaps, you find a better fit in politics?
 
  • #60
http://members.aol.com/intwg/trolls.htm#WIAT "What Can be Done about Trolls?

When you suspect that somebody is a troll, you might try responding with a polite, mild message to see if it's just somebody in a bad mood. Internet users sometimes let their passions get away from them when seated safely behind their keyboard. If you ignore their bluster and respond in a pleasant manner, they usually calm down.

However, if the person persists in being beastly, and seems to enjoy being unpleasant, the only effective position is summed up as follows:

The only way to deal with trolls is to limit your reaction to reminding others not to respond to trolls.[/color]

When you try to reason with a troll, he wins. When you insult a troll, he wins. When you scream at a troll, he wins. The only thing that trolls can't handle is being ignored."
 
Last edited by a moderator:
  • #61
Originally posted by Nereid
http://members.aol.com/intwg/trolls.htm#WIAT "What Can be Done about Trolls?

When you suspect that somebody is a troll, you might try responding with a polite, mild message to see if it's just somebody in a bad mood. Internet users sometimes let their passions get away from them when seated safely behind their keyboard. If you ignore their bluster and respond in a pleasant manner, they usually calm down.

However, if the person persists in being beastly, and seems to enjoy being unpleasant, the only effective position is summed up as follows:

The only way to deal with trolls is to limit your reaction to reminding others not to respond to trolls.[/color]

When you try to reason with a troll, he wins. When you insult a troll, he wins. When you scream at a troll, he wins. The only thing that trolls can't handle is being ignored."
I agree. Let's ignore the troll. What user is he?
 
Last edited by a moderator:
  • #62
Is this thread even about anything anymore, or shall we lock it and be done with it?
 
  • #63
Originally posted by ahrkron
Oh boy,

Physics is well beyond the stage of validating or even discussing about SR. It is not even a controversial matter any more among professional physicists.

This is NOT because of any conspiracy, or a desire to "maintain the status quo" (come on! the very idea is laughable), but because it is now firmly established (via experiment) and well understood.

Nowadays, relativistic corrections are used in myriads of experiments, and of course each one of them is first calibrated and tested with known magnitudes, to make sure that the gadget (or the 100 ton detector) measures things correctly. Any discrepancy would have been detected and studied long ago.

Due to the level of precision that current technology allows for experimental measurements, SR effects are extemely well tested. The current frontier of our knowledge is in a very different place.

Please list these experiments. Or just one at a time if you please.
I'd like to hear how SR time dilation has been tested in particular. But really, Einstein himself said that SR was not applicable if spacetime was not flat so if all experiments are done in a gravitational field, how can anyone claim SR has been tested? This seems a bit disingenuous at least.

The only tests that can be performed where spacetime is not flat are GR effects. Since Einstein himself said space-time is a kind of aether, all tests that are claimed to confirm GR then have confirmed the ether.
 
Last edited:
  • #64
Originally posted by Eyesaw
Please list these experiments. Or just one at a time if you please.
I'd like to hear how SR time dilation has been tested in particular. But really, Einstein himself said that SR was not applicable if spacetime was not flat so if all experiments are done in a gravitational field, how can anyone claim SR has been tested? This seems a bit disingenuous at least.
Here's a list of experimental tests of SR, and http://relativity.livingreviews.org/Articles/lrr-2001-4/ . Someone else may have a more comprehensive or up-to-date list.
 
Last edited by a moderator:
  • #65
But really, Einstein himself said that SR was not applicable if spacetime was not flat so if all experiments are done in a gravitational field, how can anyone claim SR has been tested? This seems a bit disingenuous at least.

The same way one can say classical mechanics has been tested. Experiments have been performed, and they agreed with results of SR. :smile:

One of the basic principles of GR is that, to put it loosely, it looks like SR on small scales. (such as a laboratory) So, if GR is an accurate description of reality, then SR should be an accurate description of reality on the small scale.

(Just like classical mechanics is an accurate description of the macroscopic world at low velocities)


Since Einstein himself said space-time is a kind of aether, all tests that are claimed to confirm GR then have confirmed the ether.

I would like to point out that the "aether" of GR is not a "classical" aether. (Just like the particles of QM are not classical particles)
 
  • #66
Originally posted by Nereid
Here's a list of experimental tests of SR, and http://relativity.livingreviews.org/Articles/lrr-2001-4/ . Someone else may have a more comprehensive or up-to-date list.

Yes, I have looked at that webpage before. But before we go
over these experiments, I'd still like an answer to how any test
can be claimed to have confirmed SR as I keep hearing,
especially from this fanatic russ_waters guy.

If a theory is based on non gravity, how can it ever be applicable
to the real world? This is especially puzzling when space-time
itself in GR is endowed with these gravitational effects so that no travel is possible by any matter through it without being affected in a gravitational manner. Using GR tests to confirm SR is very weak inductive reasoning if not a logical fallacy entirely. How do we know that in the absence of gravity, matter will move at all? How do we know that matter doesn't generate its own gravitational fields so
that one can never have a flat spacetime if matter exists? What evidence do we have that in the absence of space-time, light can move at all or even exist?
 
Last edited by a moderator:
  • #67
Originally posted by Hurkyl
The same way one can say classical mechanics has been tested. Experiments have been performed, and they agreed with results of SR. :smile:

One of the basic principles of GR is that, to put it loosely, it looks like SR on small scales. (such as a laboratory) So, if GR is an accurate description of reality, then SR should be an accurate description of reality on the small scale.

(Just like classical mechanics is an accurate description of the macroscopic world at low velocities)




I would like to point out that the "aether" of GR is not a "classical" aether. (Just like the particles of QM are not classical particles)

I think you have provided a very good example of how inductive reasoning can lead to conclusions which conflict with reality.
It's the very reason that classical mechanics had to be replaced
by quantum mechanics: assumptions we made about nature on the macroscopic scale did not accurately describe the quantum world,
even though inductively it should. In the same way, the assumptions about matter and motion through spacetime in GR may be very different from how nature behaves in the limit of GR.
Just as it is ridiculous to claim that tests on classical mechanics
are confirmations of Quantum mechanics, SR cannot be said to have been confirmed by tests of GR. But it's actually even worse since at least in Qm, we are still describing reality and not an imaginary universe as in SR.
 
Last edited:
  • #68
Originally posted by Eyesaw
If a theory is based on non gravity, how can it ever be applicable to the real world?

Because there are many situations in which the gravitational field is so close to a flat metric (i.e., what you call "non gravity") that the effect of the curvature is extremely small compared to the SR effects.

Pretty much all experimental science works this way: you care for the main effects first, neglecting other things that produce small deviations, and verify that your theory accounts for what you can measure.

You never can take into account all minute distorsions due to all imaginable effects, but that is ok because they usually introduce deviations that are smaller than your experimental precision. Think of any theory with which you are comfortable. Say, thermodynamics. Does it take into account electromagnetic fields? QCD effects? Cosmic rays? radiation pressure? background radioactivity? no, but even when all of these effects are always present, the theory is still valid since it has been proven that the only important quantities are Volume, Pressure and Tempreature (how? by varying these quantities and observing if their correlation with experiment is consistent throughout many experiments, regardless of the values of all the other quantities).
 
  • #69
Originally posted by Eyesaw
Yes, I have looked at that webpage before. But before we go
over these experiments, I'd still like an answer to how any test
can be claimed to have confirmed SR as I keep hearing,
especially from this fanatic russ_waters guy.

If a theory is based on non gravity, how can it ever be applicable
to the real world? This is especially puzzling when space-time
itself in GR is endowed with these gravitational effects so that no travel is possible by any matter through it without being affected in a gravitational manner. Using GR tests to confirm SR is very weak inductive reasoning if not a logical fallacy entirely. How do we know that in the absence of gravity, matter will move at all? How do we know that matter doesn't generate its own gravitational fields so
that one can never have a flat spacetime if matter exists? What evidence do we have that in the absence of space-time, light can move at all or even exist?
I'm a little confused. Are you asking how any test can be valid if there is more than one effect at work? There are always multiple effects being observed in experiments - the trick is knowing what is doing what.

Some of the predictions of SR are extremely simple and testing them is a relative piece of cake. GPS clocks and time dilation (my favorite) for example. Both the SR and GR effects are specific and with the equations known you can test for both at the same time.
 
  • #70
Originally posted by Eyesaw
Yes, I have looked at that webpage before. But before we go
over these experiments, I'd still like an answer to how any test
can be claimed to have confirmed SR as I keep hearing,
especially from this fanatic russ_waters guy.

If a theory is based on non gravity, how can it ever be applicable
to the real world? This is especially puzzling when space-time
itself in GR is endowed with these gravitational effects so that no travel is possible by any matter through it without being affected in a gravitational manner. Using GR tests to confirm SR is very weak inductive reasoning if not a logical fallacy entirely. How do we know that in the absence of gravity, matter will move at all? How do we know that matter doesn't generate its own gravitational fields so
that one can never have a flat spacetime if matter exists? What evidence do we have that in the absence of space-time, light can move at all or even exist?



SR did have some shortcommings which is exactely why Einstien developed the General Theory of Relativity. GR does not blow up when objects are subjected to gravity(and neither does SR with GR). The principle of equivalence allows for gravity to be incorporated into Realativity quite nicely and also imples the local validity of SR. Oh yeah, there was just yet another successful experimental test of SR by Achim Peters of the University of Konstanz in Germany. I'll even give you a link http://www.physicsweb.org/article/news/6/1/2

If your going to attack SR, then your really going attack GR as well, which, of course you couldn't do because it is such a wildly successful and widely proven theory. Even if GR & SR is not the final answer so to speak, they do have incredible explanatory power of the universe around us that we use everyday in science with a decree of precision that would be simply impossible for a theory that is just flat out wrong.

If you want more experimental confirmation, I would suggest you talk to any scientists that works with a particle accelerator, or any those that worked on the GPS sattelite network which needed timing so accurate had to be corrected for time dilation described by SR else they would be off by tens of meters.


The truth of the matter is that relativity works(both GR and SR). If you have something that works better, I'm all ears. If you want to continue asking "what ifs" until your face turns blue, be my guest, but you won't get very far in science by challenging realativity unless you have an alternate, more successful theory.
 
  • #71
Originally posted by ahrkron
Because there are many situations in which the gravitational field is so close to a flat metric (i.e., what you call "non gravity") that the effect of the curvature is extremely small compared to the SR effects.

Pretty much all experimental science works this way: you care for the main effects first, neglecting other things that produce small deviations, and verify that your theory accounts for what you can measure.

You never can take into account all minute distorsions due to all imaginable effects, but that is ok because they usually introduce deviations that are smaller than your experimental precision. Think of any theory with which you are comfortable. Say, thermodynamics. Does it take into account electromagnetic fields? QCD effects? Cosmic rays? radiation pressure? background radioactivity? no, but even when all of these effects are always present, the theory is still valid since it has been proven that the only important quantities are Volume, Pressure and Tempreature (how? by varying these quantities and observing if their correlation with experiment is consistent throughout many experiments, regardless of the values of all the other quantities).

I think Maxwell's equations point out that the speed of light
in vacuum is related to the permitivitty and permeability of the vacuum, and Einstein used his equations to arrive at the constancy of speed of light postulate in SR, no? I would think that permitivitty and permeability are descriptions only
valid for a medium, which for the vacuum was termed the luminiferous ether at the time, so if that is how one obtains the speed of
light as constant, how does Einstein get a constant c without
a medium?

And if in GR, one of the properties of space-time (which is for all purposes a light-speed determining medium except by name), curvature, is dependent on the presence of matter, how can we be sure that space-time can have any properties at all without matter? In SR's imaginary universe without matter then, light may not move at all or it could move at an infinite velocity- who knows? Surely it would depend on the permittivity and permeability of space in that case, anyhow, and if those were 0, can the speed of light still be c?

Basically, I don't think it's appropriate to consider a flat space-time to have any permitivitty and permeability properties since SR denies the existence of a light-carrying medium in its postulate of the constancy of c. The historical relevance of SR was supposed to be its elimination of the necessity for a luminiferous ether, so I'd like to see the correct version of SR right now- one in which the constancy of speed of light was derived without the permittivity and permeability of the vacuum. Anyone who thinks GR is reduced to SR in flat-spacetime has the obligation to
produce Einstein's secret derivation of the constancy of c without Maxwell's equations.

Since I don't believe such a derivation exists, the speed of light in a vacuum then depends on the permitivvity and permeability of the vacuum and can not be a constant if the permittivitty and permeability of the vacuum are variable properties.
 
Last edited:
  • #72
the speed of light then depends on the permitivvity and permeability of space and is not really a constant if those properties of space were not constant.

I think you' re right here. Permitivvity and permeability are dependend of the "medium" light is traveling. The permitivity of glass is quite different of that of vacuüm. So the speed of light is variable.
Nevertheless, this is no problem for GR. Because the fundation of GR is the (einstein)Equivalence principle:"In small enough regions of spacetime, ALL laws of physics reduce to those of special relativity, it is IMPOSSIBLE to detect the existence of a gravitational field"
This mean that , no matter in which coördinate system we are, the result of measering permitivvity and permeability of a "medium" must be the same and the speed of light is constant for that medium.

so what is your problem?
 
  • #73
Originally posted by Peterdevis
I think you' re right here. Permitivvity and permeability are dependend of the "medium" light is traveling. The permitivity of glass is quite different of that of vacuüm. So the speed of light is variable.
Nevertheless, this is no problem for GR. Because the fundation of GR is the (einstein)Equivalence principle:"In small enough regions of spacetime, ALL laws of physics reduce to those of special relativity, it is IMPOSSIBLE to detect the existence of a gravitational field"
This mean that , no matter in which coördinate system we are, the result of measering permitivvity and permeability of a "medium" must be the same and the speed of light is constant for that medium.

so what is your problem?

My problem is that the c in Maxwell's equation depended on a
medium, which for the vacuum was called the luminiferous ether
in the 19th century. Since SR eliminated the ether, it becomes inconsistent to use Maxwell's equation to derive the speed of light, which Einstein did in SR.
 
  • #74
My problem is that the c in Maxwell's equation depended on a
medium, which for the vacuum was called the luminiferous ether
in the 19th
It is not because maxwell believed in an ether, that there must be an ether too derive Maxwell's equations.
An theory is independent of the scientist, what maxwell, einstein, Newton... thinks of a theory is not important. But the ability of prediction is what a theory makes usefull.

So where we need an ether to derive Maxwell's equations?
 
  • #75
Originally posted by Eyesaw
The whole notion of an ether was incorporated into Maxwell's
equations for EM waves. Hence the equations for propogation
are wave equations and their propogation speed only dependent
on the permitivitty and permeability of the medium. Without a medium, there can be no waves so you won't have Maxwell's equations- you'd have Einstein's Undiscoverable Equations.
Eyesaw is making a very good point and the responses to his question have not really addressed the issue. I think the answer is that the medium that light travel through is space. For example, if light bends in the presense of a gravitational field it must be moving through something that has the ability to bend.
 
  • #76
Originally posted by Peterdevis
I think you' re right here. Permitivvity and permeability are dependend of the "medium" light is traveling. The permitivity of glass is quite different of that of vacuüm. So the speed of light is variable.
Light transmission through glass happens via absorption, delay, re-emission of the photons, making it appear to travel more slowly when you observe it macroscopically. Light always travels at C.

As said before, the fact that space-time has physical properties does not make it a classical "ether."
what maxwell, einstein, Newton... thinks of a theory is not important.
Except insofar as they wrote their theories of course!
I think the answer is that the medium that light travel through is space. For example, if light bends in the presense of a gravitational field it must be moving through something that has the ability to bend.
That is quite true, protonman, but it does not make space a classical ether.
 
  • #77
Originally posted by Peterdevis
It is not because maxwell believed in an ether, that there must be an ether too derive Maxwell's equations.
An theory is independent of the scientist, what maxwell, einstein, Newton... thinks of a theory is not important. But the ability of prediction is what a theory makes usefull.

So where we need an ether to derive Maxwell's equations?

Well, Maxwell's equations for EM radiation are wave equations,
so they need a medium since waves don't exist as far everyday
observations go, independent of a medium. To derive Maxwell's
equations without an ether then would require one to show
that the vacuum is completely empty, else one can always assume
a medium that is just too small to be observed.

Since this can never be done, it's more economical to assume light, if it is a wave, requires like every observable wave phenomenon,
a medium for propogation. So you need an ether to derive Maxwell's equations.

An alternative would be to consider light as particles, in which case you would have to explain why their velocity is not source dependent like other ballistic particles.

Einstein did neither so his postulate of a constant c in SR then has neither physical nor mathematical basis since he disposed of the ether.
 
  • #78
Eyesaw wrote: *SNIP
Since this can never be done, it's more economical to assume light, if it is a wave, requires like every observable wave phenomenon, a medium for propogation. So you need an ether to derive Maxwell's equations.

An alternative would be to consider light as particles, in which case you would have to explain why their velocity is not source dependent like other ballistic particles.
So, here's some of what's been observed about light:
- double-slit experiment -> "wave-particle duality", well accounted for by quantum mechanics
- photoelectric effect -> light as photons
- gravitational bending and Shapiro time delay -> predicted and well accounted for by GR.

In summary, all observations match predictions of the theories.

If your view of 'waves' requires they need a medium for propogation, then either 'light is not a wave', or 'your view of the nature of waves is incomplete' (or both).

If your view of 'ballistic particles' requires that their velocity is source dependent, then either 'light is not a ballistic particle', or 'your view of the nature of ballistic particles is incomplete' (or both).
 
  • #79
Originally posted by Eyesaw
Well, Maxwell's equations for EM radiation are wave equations,
so they need a medium since waves don't exist as far everyday
observations go, independent of a medium.

Why not? What substrate is implied by Maxwell's equations?

To derive Maxwell's
equations without an ether then would require one to show
that the vacuum is completely empty, else one can always assume
a medium that is just too small to be observed.

"Too small"?

The light that we see from the sun travels 93 million miles to Earth! In what sense is this supposed medium "too small"?

Since this can never be done, it's more economical to assume light, if it is a wave, requires like every observable wave phenomenon,
a medium for propogation. So you need an ether to derive Maxwell's equations.

Why is it more economical to add an assumption?

An alternative would be to consider light as particles, in which case you would have to explain why their velocity is not source dependent like other ballistic particles.

We do consider light as particles, when the intensity of the radiation is sufficiently weak. But why do we have to explain why the velocity of those particles is not source dependent? That is like demanding an explanation of why the charge of an electron has the value that it does.

Einstein did neither so his postulate of a constant c in SR then has neither physical nor mathematical basis since he disposed of the ether.

No, SR has both. Its mathematical basis follows from the (very well tested) Maxwell equations. Its physical basis follows from all the experiments that have been done to corroborate it.
 
  • #80
Mentor note:
This past page or two has been getting back on track to a decent discussion. If the nonsense of the first 5 pages starts again, then this topic is over.
 
  • #81


Originally posted by pelastration
Nereid,

have you even seen this quote of Maxwell?

"In speaking of the Energy of the field, however, I wish to be understood literally. All energy is the same as mechanical energy, whether it exists in the form of motion or in that of elasticity, or in any other form. The energy in electromagnetic phenomena is mechanical energy."
--- JAMES CLERK MAXWELL

I found that on a website of Joseph Newman, never found other oringinal references. But it fits in my ideas about multi-layered spacetime where membrane friction creates all other interactions.
AFAIK, Maxwell died before the results of the Michelson-Morley experiment were published (and he died even before M&M began their experiment?) So we cannot know how he would have felt, or what he would have thought, had he lived another few or 20 years. Certainly, Maxwell died before quantum weirdness was discovered.

As others have said here, we're on a journey, learning new things all the time ... finding new things doesn't diminish the great contributions of past giants, but neither would they wish us to stay stuck with only what they found.
 
  • #82
A question which was posed earlier, and I think needs re-iterating, is why do we need an ether? There is this prevailing notion from some posters that the universe must behave as Newtonian physics predicts, and that "fanciful" theories such as quantum mechanics and relativity theory must be incorrect because they contradict classical Newtonian intuition -- despite the fact that Newtonian physics is a limiting case in both theories.

Perhaps those calling for proof of why they should believe modern theories should in turn tell us why Newtonian physics is expected to be the ultimate theory.
 
  • #83
Originally posted by GRQC
Perhaps those calling for proof of why they should believe modern theories should in turn tell us why Newtonian physics is expected to be the ultimate theory.
Its pretty simple: Newtonian physics 'makes sense.' A wave without a medium in which to propagate? Absurd!

That the coolest thing about QM: pretty much everything in the entire theory contradicts classical interpretations of how the world 'should work.' Its bizarre. Rediculous. Illogical. But with so much clear and incontrovertible evidence that the bizarre is for real, we have no choice but to change our view of how the world 'should work,' not look for a reason why QM could be wrong.
 
  • #84
That is quite true, protonman, but it does not make space a classical ether. [/B]
Why not? It seems logical to consider space as the medium of propagation of light. Yes, not in the classical sense of an ether that can serve as an absolute reference frame but none the less a medium of propagation.

In addition, it may simply be the case that the medium of propagation has not been searched for properly. In any experiment there are assumptions. If the wrong ones are made the outcome will be incorrect or at least inconclusive.
 
  • #85
Originally posted by Eyesaw
Well, Maxwell's equations for EM radiation are wave equations,
so they need a medium since waves don't exist as far everyday
observations go, independent of a medium. To derive Maxwell's
equations without an ether then would require one to show
that the vacuum is completely empty, else one can always assume
a medium that is just too small to be observed.

Since this can never be done, it's more economical to assume light, if it is a wave, requires like every observable wave phenomenon,
a medium for propogation. So you need an ether to derive Maxwell's equations.

An alternative would be to consider light as particles, in which case you would have to explain why their velocity is not source dependent like other ballistic particles.

Einstein did neither so his postulate of a constant c in SR then has neither physical nor mathematical basis since he disposed of the ether.
This is excellent work. What you are doing is here is a breath of fresh air. Another related question to raise is that if SR is incorrect how do you explain all the phenomena that have been explained using SR? For example, Pion decay experiements.
 
  • #86
Originally posted by Nereid
So, here's some of what's been observed about light:
- double-slit experiment -> "wave-particle duality", well accounted for by quantum mechanics
- photoelectric effect -> light as photons
- gravitational bending and Shapiro time delay -> predicted and well accounted for by GR.

In summary, all observations match predictions of the theories.

If your view of 'waves' requires they need a medium for propogation, then either 'light is not a wave', or 'your view of the nature of waves is incomplete' (or both).

If your view of 'ballistic particles' requires that their velocity is source dependent, then either 'light is not a ballistic particle', or 'your view of the nature of ballistic particles is incomplete' (or both).
So basically when new evidence doesn't fit your previous definitions and rules just change the them.
 
  • #87
Originally posted by protonman
So basically when new evidence doesn't fit your previous definitions and rules just change the them.

Exactly. It's the best anyone can do.
 
  • #88
Why not? What substrate is implied by Maxwell's equations?
What is a wave?
 
  • #89
Originally posted by protonman
What is a wave?

A wave is any traveling, periodic disturbance in a physical field.

My turn: What substrate is implied by Maxwell's equations?
 
  • #90
We do consider light as particles, when the intensity of the radiation is sufficiently weak. But why do we have to explain why the velocity of those particles is not source dependent? That is like demanding an explanation of why the charge of an electron has the value that it does.
If you people were ever called to debate your views with those who know logic you would be laughed out of town.

Think about your attempt parallel reason. The reason you would have to explain why light is source independent is because everything else we know that is a particle is source dependent. You comparison to explaining the charge of an electron is completely off the mark.

This is what I have been saying all along. There are no more great thinkers. Just regurgitations.
 
  • #91
Originally posted by protonboy
If you people were ever called to debate your views with those who know logic you would be laughed out of town.

Perhaps you wouldn't mind posting some actual logic then.:smile:

Think about your attempt parallel reason.

I did. Both questions get to the heart of the matter, which is that the universe is not known a priori. We don't have the answer to either question for that reason. It's a pity that you still don't understand that simple point, as I have elucidated it to you several times now.

The reason you would have to explain why light is source independent is because everything else we know that is a particle is source dependent. You comparison to explaining the charge of an electron is completely off the mark.

Everything else we know of that is a particle satisfies the exact same velocity addition law that light does. We cannot explain why that particular velocity addition law holds, any more than we can explain why the electron has the charge that it does.


This is what I have been saying all along. There are no more great thinkers. Just regurgitations.

Look in the mirror, protonboy.
 
  • #92
Oh yes, one more thing:

What substrate is implied by Maxwell's equations?
 
  • #93
Ummmm. Yeah...


If I am sidetracking something, let me know. What evidence is there for "ether"? Can somebody answer that for me?
 
  • #94
That will be enough of that.

--Tom[/color]
 
  • #95
Can someone give me a POLITE answer?
 
  • #96
I did. Both questions get to the heart of the matter, which is that the universe is not known a priori. We don't have the answer to either question for that reason. It's a pity that you still don't understand that simple point, as I have elucidated it to you several times now.
What do you mean by the universe anyway?
 
  • #97
Originally posted by protonman
That will be enough of that.

--Tom[/color]
Okey Dokey Tom!
 
  • #98
Originally posted by protonman
What do you mean by the universe anyway?

By "the universe" I mean "the totality of material existence".

OK, that's 2 of yours I answered. It's only fair that I get one now.

What substrate is implied by Maxwell's equations?
 
  • #99
Originally posted by Tom
By "the universe" I mean "the totality of material existence".

OK, that's 2 of yours I answered. It's only fair that I get one now.

What substrate is implied by Maxwell's equations?
I know something a priori about material existence.
 
  • #100
What substrate is implied by Maxwell's equations?

Ooh, call on me, Teach!
 
Back
Top