Luminiferous Ether

Discussion in 'Physics & Math' started by Vern, Aug 31, 2006.

  1. Vern Registered Senior Member

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    A headline in this month's New Scientist reads, "Ether returns in bid to oust dark matter".
    The article goes on to describe some hypothesis about using the idea of an aether medium to modify gravity and so explain why stars in galaxies move faster than they should.

    My thought was; why don't we just go back to Lorentz; he developed a perfectly good theory that tied relativity phenomena directly to a universe in which the final irreducible constituent of all physical reality was the electromagnetic field. It did this in classic space-time.

    So I thought of a contest; in such a universe that consists only of electromagnetic phenomena, what would be an experiment that a person could conduct that would show that they were not in a universe just like our own. I blogged it here.

    The only thing I could come up with was the neutrino. I couldn't explain how a neutrino could exist in that context.
     
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  3. DaleSpam TANSTAAFL Registered Senior Member

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    The Lorentz ether theory is experimentally indistinguishable from special relativity. If, for aestetic reasons, you prefer LET over SR that is certainly your perogative.

    -Dale
     
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  5. Vern Registered Senior Member

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    Hi Dale; there is a great difference. If the final irreducible constituent of all physical reality is the electromagnetic field and that is the seat of relativity phenomena, nature is fundamentally different than SR suggests. No experiment, so far, can show the difference, but surely there is some experiment that would.

    Thanks for your thoughts.
     
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  7. DaleSpam TANSTAAFL Registered Senior Member

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    LET and SR both use the Lorentz transform to make all of their predictions. Sure, there are great philosophical and aestetic differences between the two theories, but they are experimentally indistinguishable.

    If you think that "surely there is some experiment that would" distinguish the two then please propose it. Please describe how you think the same Lorentz transform formula can be used twice on the same experimental setup to get two different answers.

    -Dale
     
  8. Vern Registered Senior Member

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    695
    Correct spelling

    You're right, of course, about the math. But if you start with the first postulate of Lorentz that the seat of the field (electromagnetic) is the empty space and apply Maxwell's equations to points in space (aether) you get gravitational phenomena. SR wouldn't do that. So while relativity predictions are the same in either context, the fundamental philosophical differences have to produce different outcomes for other real things; seems to me.
     
  9. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Hi Vern.
    I am not qualified to get into the math anymore (or inclined to do so) but I did visit your site. I stopped reading there after brief glance at the first drawing which is in error. It clearly shows in phase peaks of the magnetic and electric fields, where as they must be 90 degrees out of phase to conserve energy. For simple illustration of the error, note they both go to zero at same time (zero energy at that time)

    In fact one is a sin function and the other a cos funcion of time and energy is proportional to the square of their amplitude. Thus, energy is conserved (not a function of time) because:

    Sin^2 + Cos^2 = 1, a constant, indepentant of time, even though both terms on the left hand side of this equation, separately considered, are strong functions of time. I.e. at peak of the E field, all the energy is electrical and at peak of the magnetic field it is all magnetic.
     
  10. Vern Registered Senior Member

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    695
    Hi Billy T; I'm a great fan of your writings and your posts, but I think you're wrong here. It is change in one field that produces the other; maximum rate of change happens in the magnetic field at the same time as maximum change is happening in the electric field. It least that is the way I've seen it for the last fifty years that I've been involved with electronics. But my mind ain't what it used to be.

    Thanks for looking.
     
  11. Vern Registered Senior Member

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    695
    Hi again Billy T; after a couple of hours of research I can say without doubt that the electric field and the magnetic field of a propagating magnetic field are in phase; not ninety degrees out as you suggested. You might want to look it up. Here's Maxwell's take on it.

    Thanks again for your interest.

    Vern

    Edit: Here's a link to an explanation from another source.
     
    Last edited: Aug 31, 2006
  12. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I did look very briefly at you Maxwell's reference, but saw nothing there to change my mind. I again call your attention to the violation of energy conservation mentioned in prior post. Perhaps you can understand why "in phase" is impossible if we shift to very low frequency EM wave, instead of light. (I will soon tell why also, from Maxwell's equations, but the energy argument is very simple and irrefutable.)

    These low frequency waves (US Navy built a 75 hertz transmitter in Minnesota as initial test of system to communicate with submerged submarines - depth of penetration is directly proportional to wave length, but information transfer rate is inversely proportional so it would take minutes for each message character and system was dropped, for this and other reasons, including farmers objecting to the many mile long antennas buried in their pastures - radio active milk and all that was discussed in the local papers.) Point is EM waves at 75 hertz exist and have been used - even 60 hz power lines radiate earth's existence into space. (A nice gesture to guide aliens here, don't you think?)*

    Consider the time interval near the time when both your inphase E and M componets are near zero amplitude - to be specific from 10% of peak amplitude thru zero and back up top 10% pof peak again - with 75 hertz this is quite a few ms at least. During this time interval, at least 99% of the energy has "vanished." (All of it as E & M waves go thru zero amplitude.) Where did it go? How is it recreated? Where did 99% of the energy come from when the EM wave is again at the peak? Are you really willing to give up conservation of energy?

    Now from Mawell’s equations:

    In vaccum it is most simple, so I assume that. His equation relating E to B is:

    E = -dB/dt (Almost sure their is a minus sign, but it has been a long time and my point does not change if there is not one.)

    Now when is dB/dt taking its max value, or B changing most rapidly?

    Certainly not at the peak of the B oscillation. (Then the derivative is zero.) Correct answer is when the B field is passing thru zero. That is the peak of the E field occurs when the zero crossing of the B field occurs - or as I said the E and B fields are 90 degrees out of phase.

    Same again, little more mathematically:
    Let B=sin{(x/lamda) - (omega)t}
    and now calculate dB/dt

    There are some constant factors that come out (related to the difference in the B and E units basically) which I will lazily call "K"

    E = - dB/dt = K cos{(x/lamda) - (omega)t}

    Cos is max 90 degrees from the sin function.

    I rest my case - if that did not at least give you some "doubts" I do not know what would.
    ----------------------------------------
    *They no longer use the 60 hz as high powered TV is transmitted in form of horizontal beams now sweep the heavens 360 every 24 hours. I am sure they are now enjoying old "I love Lucy" and The Ed Sulivan shows (Elvis lives, still.)

    PS, later by edit - now have looked at your second ref. - it is as wrong as you are, and I now understand why you made the mistake, following them.

    This is a good example of why I like to think for myself and rarely turn to internet for answers.
     
    Last edited by a moderator: Aug 31, 2006
  13. Vern Registered Senior Member

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    695
    an explanation from another source.

    In Maxwell's paper he states that both the electric and magnetic component have half their energy(potential) stored in the medium. They do not swap it back and forth between the electric and the magnetic as you seem to infer.

    If I'm wrong, I'm in bad trouble; I'm an Electronics engineer; now retired for 20 years after 30 years in the field. But that don't mean I can't be wrong. Will you check out the second source and get back to me; you've got me scared now.
     
    Last edited: Aug 31, 2006
  14. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I did -see edit comment added to my prior post.
     
  15. Vern Registered Senior Member

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    Thanks Billy T. I've visited half a dozen places searching Google for "electromagnetic phase relationship" and every one I've found that talked about it had them in phase. Here's another one:

    Olympusmicro.com

    And this from another forum
     
    Last edited: Aug 31, 2006
  16. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Thosuands warned Columbus that the world was flat and he would fall off the edge. 100 German scientists sign notice condeming Einstein's "Jewish physics" - try thinking instead of searching. The internet is full of crap, but I am sure if you persist, eventually you will find someone who knows E = -dB/dt is one of the four Maxwell Equations and understand this forces the E and B fields to be 90 degrees out of phase.
     
  17. Vern Registered Senior Member

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    695
    Hi Billy T; I know you are a physicist and much better equipped to know this than I am. But when I read Maxwell's explanation, it makes sense that the fields are in phase. Other physicists, mentors in popular science forums. have it in phase. Billy T. you are the only honest to goodness physicist I've found who has the electric and magnetic components 90 degrees out of phase.

    Did you see my thread in Physics Forums. A mentor promptly replied that the fields are in phase.

    Edit: I can follow your partial differentials to some extent; it's been years since I got my head around that; but is it possible that we are missing that it is the change that produces a changing field, that must itself simultaneously produce a changing field??
     
    Last edited: Aug 31, 2006
  18. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I have said about everything I can to make you understand the truth. Energy is conserved as sin^2 + cos^2 = 1 and the 90 degree phase difference follows very simply and directly from E = -dB/dt. I will not discuss it more.

    This is not the first time at sciForums I have explained the truth (well I think) and not persuaded even one poster in active threads. For two examples:

    (1) Magnetic field lines do not exist. - They are only a convenient way to think of induction. (Even Gauss, who thought this convenient aid to though up, understood this.) For demonstration imagine a torrus transformer of high permeability material, weakly energized (far from saturation) by "primary coil" wound tightly around it. The minor radius of the torrus, r, is much smaller than the major one, R. I.e. r< < < R

    The secondary is a single circular turn of radius R and one part of it is passing thru the center of the torus, very far from any significant B field (all other parts are even farther way from most of the torrus as the plane of secondary turn is perpendicular to that of the torrus.

    There is current in the secondary, despite the fact there is essentially no field (and certainly no field lines) at any point near the secondary turn. If it helps, let R/r = 10,000 or larger. You can stick a Hall effect magnetic probe near secondary and see that none of it is in B field.
    and
    (2) There was a thread asking about what part of a pot, heated from below, with water gently boiling in it is hottest. I correctly pointed out that inside the tiny steam bubbles just forming by stastical densitry fluxuations (usually in the "micro cracks" between the metal crystals of the pot) and then released into the water above bottom of pot, the internal pressure can be well above atmospheric, because of the surface tension in the interface between steam inside and water outside, which if pot is not ridiculously tall is still essentially atmospheric in the water. (Inside the very smallest, just formed bubbles it can easily exceed 2 atmospheres. What is the temperature of steam at two atmospheres? Answer: much above 100degrees C. that bubble rapidly expands (basically adiabatically cooling to 100C as time is short) or it collapses.* However, this truth did not faze any of the dozens of posters who continued to give their opinions.

    PS I hope you see the light (pun intended) or I shall be forced to add your resistance to this growing list.
    ---------------------------------------------
    These tiny bubles can also be formed by rapid reduction of pressure waves (SOUND) or by the prop of a boat. In this second case the interface speed can become supersonic, and deposit a lot of energy on small spot (It is called "cavitation corrosion.") In the first case, in very pure water, with very well focused high power sound wave to an internal water POINT, the collapsing bubble can reach such high temperature that light is emitted in a very brief flash!
     
    Last edited by a moderator: Aug 31, 2006
  19. DaleSpam TANSTAAFL Registered Senior Member

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    Hi BillyT,

    From my understanding Vern is correct. Your citation of Maxwell's equation is a good idea, but you are incomplete. In free space you have no currents and no charges so Maxwell's 4 equations simplify down to 2 equations (considering a single spatial dimension):

    dE/dx = -dB/dt
    dE/dt = -c&sup2; dB/dx

    So when the temporal derivative of one is maximal the spatial derivative of the other is minimal (maximally negative). If you consider a simple single-frequency sinusoidal plane wave you find that this happens for E and B in phase. In the above equations:

    E = Emax cos(kx-wt)
    B = Bmax cos(kx-wt)

    is a solution while

    E = Emax cos(kx-wt)
    B = Bmax sin(kx-wt)

    is not a solution.

    With the in phase solution you also find that Emax/Bmax = E/B = w/k = c so the ratio is constant, not the sum of the squared magnitudes as you indicated.

    Now, your point about the energy is interesting, but you need to recall that the square of the magnitude of the E and B fields are not related to energy but to energy density. So, at a given location in space energy density is, in fact, not constant. To get energy you must integrate over some volume. If you integrate the squared E and B fields over a volume and the Poynting vector over its surface then you will find that the change in the energy inside the volume is exactly equal to flux across the surface. Energy is conserved. The fact that the energy density at a given location is not constant, or that the regions of greatest energy density move, should not be too surprising since you know that EM waves transmit energy.

    -Dale
     
  20. kevinalm Registered Senior Member

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    993
    Um, Billy, the E and B fields in a em wave are in phase. E x B is the Poynting vector that gives the instataneous energy transfer (watts per m^2). Energy is conserved by the fact that the em energy is moving, at the speed of light.

    What allows the in-phase relationship is that you have the equation wrong. The dynamic equations relate a time rate of change in field intensity at a point (dE/dt or dB/dt) to a vorticity about that point of the other field (Del x B or Del x E respectively).
     
  21. DaleSpam TANSTAAFL Registered Senior Member

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    "Seems to me" is a pretty weak argument. If you can propose any specific experiment, no matter how fantastic or technologically infeasible, where the two theories make quantitatively different predictions then we can talk again. Otherwise, math trumps "seems to me" every time.

    -Dale
     
  22. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    IF THAT IS CORRECT, Maxwell equation, instead of E = -dB/dt, then I yield. Perhaps my memory has failed me?
     
  23. Vern Registered Senior Member

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    DaleSpam: Thanks for clearing things up.

    I guess the point I was trying to make is that the fundamental philosophical differences should lead to fundamental differences in our understanding of how the universe is built. If we can't warp space and time, but must instead explain all observations by warping only matter and clocks we should end up at a different place.

    But by now I'm getting a little too warped to think straight

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