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Michelson - Morley Experiment Revisited

  1. May 18, 2004 #1
    okay! now I would like to discuss the problems with the Michelson - Morley Experiment [link]

    I believe the experiment was flawed, both technically and conceptually
    due to crude (19th century) methods and ill conceived assumsions

    for example: why should aether form an absolute reference frame to the rest of the universe? is there any reason to assume that aether cannot be in a state of flux along with all the matter in the universe? if aether was nothing more than a medium through which electromagnetic radiation propagated - would such a medium ramain static with so much wave propagation saturating the cosmos?

    the experiment anticipated interference fringes between the light which had passed through the two perpendicular arms of the apparatus. these would occur since the light would travel faster along an arm if oriented in the "same" direction as the aether was moving

    but this assumes that the speed of light is not constant
    has the speed of light not been proven to be constant?
    so there could be no interference fringes between perpendicular light sources

    this is the biggest flaw of the experiment
    but the problems don't end here

    the same effect would be achieved if the arms of the interferometer were not of the same length - but constant realtime adjustment of the interferometer was not possible with the precision necessary to overcome the mechanical variables of a crude apparatus floating in a basin of mercury - this would have required a computer control system which was a century away

    In 1895 Lorentz concluded that the "null" result obtained by Michelson and Morley was caused by an effect of contraction made by the aether on their apparatus and introduced the length contraction equation

    a new sequence of equations were later developed by Poincaré
    which lead to Einstein's outright rejection of aether and the acceptance of his Special Relativity as a new standard model

    were the Physics community too quick to abandon the aether premise
    and jump on the Special Relativity bandwagen?

    playing devil's advocate: :devil:

    what if aether propagates all matter?

    what if in fact all matter itself is nothing more than vortices of aether?
    with light waves being aether waves - in which case photons do not exist
    with gravity waves being aether eddy currents

    so, let's trash this theory once and for all!

    however if there is no real argument against it's existence
    then it may be time to reopen the case for aether :confused:
     
    Last edited: May 18, 2004
  2. jcsd
  3. May 18, 2004 #2

    russ_watters

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    Contrary to the insistence of ether "theorists," physics has not stagnated for the past 100+ years.
     
  4. May 18, 2004 #3
    I remember reading somewhere that the original Michelson - Morley Experiment was flawed as they had used a fixed mounted mirror instead of a free mounted mirror. This had something to do with the American Air Force's GPS Project and the "Sagnac Effect" http://www.mathpages.com/rr/s2-07/2-07.htm They proved I think that the Earth does move a "aether" of sorts
     
  5. May 19, 2004 #4
    physics has never stagnated

    there is no problem advancing physics under a false or ad hoc model
    as long as the model fits observations and calculated predictions

    this is not to say that SR is a false model, but it is (in any case) a theory
    and all theories should be subject to relentless scrutiny

    all viable theoretical models deserve examination - popular or not

    nuclear physics would have advanced with or without Special Relativity
    E=MC2 was not Einstein's creation - it existed before SR

    Non-Relativistic Quantum Theory would still have lead to nuclear fission
    and all the advances of technology during the past century
    those who believe that advances in physics owe their existence to Einstein
    are delusional

    the most dangerous attitude a Physicist can adopt is one of arrogant complacency, that Einstein has lit the way, and there is nothing more to do than follow his light of truth - this attitude is as close to stagnation as science can achieve
     
    Last edited: May 19, 2004
  6. May 19, 2004 #5

    russ_watters

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    The Sagnac Effect is perfectly well accounted for by Relativity. It des not require an aether. That it does is a common misunderstanding.
    If it fits observations, how is it false? Conversely...?
    Agreed. Therefore, aether "theories" should be discarded.
    I'm not sure that's true (source?), and I don't see the relevance.
    There is certainly a lot of physics that does not depend on Einstein's work - the vast majority though, does.

    In any case, you are displaying the usual ether theory slant: ether theory isn't about investigating a viable theory, it exists to attack Einstein himself and the work he contributed to for personal reasons. Thats the opposite of how science works: science isn't about knocking down someone else's theory to further yours, but rather scientifically proving yours independent of any competing theory.
     
    Last edited: May 19, 2004
  7. May 19, 2004 #6
    on what basis? the Michelson-Morley fiasco?

    have you personally gathered experimental evidence disproving aether theory?

    or are you just so confident that everything you read regarding the standard model and all criticisms against aether theory are beyond reproach?

    btw. I'm a big fan of Einstein, and I'm neither for nor against his theories

    I keep an open mind, and in this topic I'm playing devil's advokate.. because 99% of the scientific community think they have all the answers, although they don't... (not even close) so they need to be reminded of the fact

    I think it's more accurate to say that the majority of modern physics is based on Einstein's work, and would not get funding otherwise

    the amount of funding that non-standard physics gets is a joke
     
    Last edited: May 19, 2004
  8. May 19, 2004 #7
    the relevance is that Einstein borrowed ideas from others
    without listing their sources [link]


    Olinto De Pretto published the expression E = m_Mc^2 in the science magazine Atti (Atte) in 1903. His expression was a speculation that was not derived from more fundamental principles such as special relativity. There is considerable evidence that Einstein was aware of the De Pretto speculation and that this was an additional driving force behind his faulty attempt to derive this expression for radiation, at the least. There is also very strong evidence that Einstein never gave De Pretto any credit for his great insight. It is an absolute requirement that one must do a certain amount of literature "research" prior to publishing a claimed new disclosure
     
    Last edited: May 20, 2004
  9. May 19, 2004 #8

    russ_watters

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    Certainly not. Like I said (and you've now displayed why what I said is key): Contrary to the insistence of ether "theorists," physics has not stagnated for the past 100+ years.
    Again, you have the scientific process backwards: its not up to me or any physicist to disprove ether theories. The problem with them is simple: There is no experimental data that requires an ether to be satisfactorally explained, therefore ether "theorists" aren't really theorizing about ether, but rather assuming it to exist without evidence. Hence the quotes around the word "theory."
    No one who believes they (or science) has all the answers becomes a scientist: if they (or science) already had all the answers, there would be nothing for scientists to do. Science is a search for answers.
    If it were worth researching, people would research it.
    Riiiiiiight.
    Still not seeing any relevance: your personal opinion of Einstein, even if your allegations are true, do not constitute a scientific arguement for ether theory.

    Again, you are fixated on attacking Einstein (and not even his theories, just the man), when you should be making arguments for your theory.
     
    Last edited: May 19, 2004
  10. May 19, 2004 #9

    russ_watters

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    Regarding your link, as a former student at the Naval Academy (not an alum), I am dismayed that it would have such a man teaching there and thankful I never had a class with him.

    That link is an attack on Einstein for religious reasons.
     
  11. May 20, 2004 #10
    the main focus of this topic is that the MM experiment was flawed
    this is the only issue which needs to be addressed here
    anything else is off topic

    aether was postulated as a medium through which light propagated
    (this is not my theory, I'm simply stating historical fact)

    in any case no theory has proved one way or another how light propagates
    aether is just as viable a premise as any SR has provided, if you stop assuming that aether is a fixed reference frame

    and this is the whole of my argument, not attacking Einstein
    Einstein was a great theorist, so let's leave it at that

    I am dismayed as well, religion has no place in science

    I am not supporting nor advokating any personal attacks on Einstein

    here is another (non-religiously motivated) link

    only the essential fact that, Olinto De Pretto is the author of E=MC2 and not Einstein, which is not an attack, but a fact

    there are many other sources proving this fact, the most obvious being the original 1903 publication itself, but this is not so important as the original statement I made - which is that E=MC2 predated SR, that's the only point - that nuclear physics would have prevailed in the absence of SR
     
    Last edited: May 20, 2004
  12. May 20, 2004 #11

    Integral

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    OK.

    Since the MM experiment was performed about the time of Einstein's birth, and there are claims that Einstein did not even know of the MM result why do you even mention Einstein or SR. Neither have anything to do with how MM experiment was performed or the interpretation of the results. If you really want to discuss MM why don't you?

    I do not get a feel from your posts, what the trouble with the MM was just what was wrong with it? Please be specific and, as you, yourself requested, stick to the topic.
     
  13. May 20, 2004 #12
    I do not wish to discuss Einstein or SR

    this topic was posted for the sole purpose of dicussing the shortcomings of the Michelson Morley Experiment, it's mechanical faults, it's faulty premise, how a better aether experiment might be designed and executed to prove or disprove the existance of aether

    Einstein and SR were only mentioned briefly, in a relevant manner

    the first statement is historical fact - the later is a question regarding the abandonment of aether theory on a faulty premise

    both of which are relevant to the topic

    most replies have focused on Einstein, SR, how horrible people are who criticise poor Einstein, or how aether theory doesn't deserve to be dicussed, and how only theories which have the stamp of approval from russ_watters should be discussed

    so don't complain to me if this thread is diverging
     
    Last edited: May 20, 2004
  14. May 20, 2004 #13
    I personally believe that there is an undiscovered medium for the propagation of light. However, I thought that Einstein later did not reject aether theory, but contended that it was not necessary for the observations to fit with his theories.

    "It would have been more correct if I had limited myself, in my earlier publications, to emphasizing only the nonexistence of an ether velocity, instead of arguing the total nonexistence of the ether, for I can see that with the word ether we say nothing else than that space has to be viewed as a carrier of physical qualities."
    --Albert Einstein

    "Recapitulating: we may say that according to the general
    theory of relativity space is endowed with physical
    qualities; in this sense, therefore, there exists ether."
    --Albert Einstein

    Here he was speaking, I believe, about the curving of space-time as a form of ether "fabric".
     
  15. May 20, 2004 #14
    Hey guys heres another link to muse over heres the abstract
    Special relativity theory (SRT) claims equivalence of all inertial frames, but it is generally acknowledged that there exists a dipole temperature distribution in the cosmic background radiation (CBR), which indicates that the solar system is moving through this unique inertial frame at a speed of approximately one percent of the speed of light. This evidence for a unique frame conflicts with SRT, and so motivates a search for additional evidence. Presumably, any ether drift should be directly detectable via experiment in either an earth-centered frame, or a sun-centered frame, or both. Spinning Mossbauer experiments, the Global Positioning System (GPS), and Very Long Baseline Interferometry (VLBI) are here analyzed for any evidence of ether drift; i.e., for evidence that the speed of light is not isotropic in all inertial frames. Though none of the experiments provides any direct evidence for ether drift, they do provide substantial indirect evidence


    http://www.egtphysics.net/Ron1/EtherDrift.htm
    http://www.newtonphysics.on.ca/Illusion/ Another link
     
    Last edited: May 20, 2004
  16. May 20, 2004 #15

    russ_watters

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    Yes, I know: and that is its basic flaw.
    Mathematically, sure - but how many assumptions do you have to pile on top of each other before deciding you've built a house of cards? First you assume there is an ether, then you assume it moves in such a way that every experiment ever devised to find it (or that could be dependent on it) has failed to find it. You don't consider that absurd?

    A great similar example is the epicycles of Ptolmey. By assuming enough epicycles (dozens), you can eventually build a model that fits reasonably well with the observed motion of the planets. However, like ether theory, you can't derive it from first principles and you can't use it to make any predictions. So what good is it?
    That's just it, energia - why does the MM experiment even need to be a part of this discussion? We know its old and we know it has limitations. Like I said: science has not stagnated since then (not even ether theory). Wouldn't it be better to examine the implications of GPS or lunar ranging experiments on ether theories?
    Its your thread - I've only responded to the things you mentioned: I focused in on your statements about Einstein because they are revealing about your purpose and particular bias (note: everyone has a bias). If you want to talk about ether "theories" and how they could/could not work and how to test them, do it! (looks like flash007 is getting it started...)

    flash007, there are several misconceptions in that abstract. First is the same one that energia is operating on: evidence we have does not require an ether, it only doesn't absolutely rule it out. Fitting ether "theory" to the evidence we have requires assumptions and convoluted math, yeilding a "theory" of little theoretical value. To be specific: GPS has not detected any anisotropy in the speed of light despite the fact that at any given moment there are groups of satellites testing for it in at least 6 different referece frames simultaneously as well as ground stations. Making an ether "theory" that isn't killed by that is tough. The "indirect evidence" statement is a stretch - the best that can really be said is the evidence doesn't speccifically forbid it.

    The CMB, though a useful frame of reference, is not the universal preferred frame that Relativity discarded: the laws of physics work the same in it and outside of it.

    The most important part of the abstract though is this:
    Indeed. Has it? (hint: no). That, energia, is why at this point pursuit of ether "theory" is a waste of time. If at some point in the future evidence is found that conflicts with Relativity, then maybe it will be time to go back to it. Right now, ether "theorists" are pumping a dry well based on wishful thinking.
     
    Last edited: May 20, 2004
  17. May 20, 2004 #16

    russ_watters

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    Let me ask you this, energia: is there anything (any piece of evidence, explanation, etc) that if found that would cause you to abbandon ether theory?
     
  18. May 20, 2004 #17
    I understand you now

    and yes, it would be better to examine the implications of GPS or lunar ranging experiments on aether theories..

    however we start with the MM experiment because history has created a stigma against aether - due to the success of SR

    even in spite of the fact that Einstein himself did not object to the existence of aether

    as far as bias, I am biased towards the truth, whatever it may be
    I will agree to anything that is true

    I did not open this topic to disprove SR - I believe SR predictions fit observations quite well - and with very few exceptions

    as far as most statements you've made, I'm in agreement with you

    however I disagree on the point that aether need not be discussed

    Aether MUST be discussed as long as the true nature of light is unknown

    as a physicist you must agree that physics does not exist for the sole purpose of launching satellites into orbit



    as scientists we search for the true nature of all phenomena
    there should be no limit to the search


    absolutely! if an experiment could be designed and implemented that would conclusively disprove the existance of aether, I would concede that aether theory was dead

    the problem of devising such an experiment is no simple task
     
    Last edited: May 20, 2004
  19. May 20, 2004 #18
    before continuing this discussion, I would like to state for the record that the existence or non-existence of Aether may not be of any consequence with regard to standard astrophysical models (disclaimer) in as far as the true nature of light propagation is not required for practical calculations and predicted results

    the discussion of aether theory is (therefore) for the sole purpose of understanding the true nature of light propagation, and the subsequent revision of standard astrophysical models - in regards to the true nature of light propagation, and possibly other aspects as a consequence, depending on the final conclusion
     
    Last edited: May 20, 2004
  20. May 20, 2004 #19
    Why not start by resolving the whole wave-particle duality thing first ? :smile:
    An aether model requires a wave-model of light doesn't it ?
     
  21. May 20, 2004 #20
    the most common opinion was that light travelled in the form of waves through an aether which was an absolute reference frame

    Thomas Young's double-slit experiment (c1805) was an attempt to resolve the question of whether light was composed of particles (corpuscular theory), or consisted of waves travelling through some aether, just as sound waves travel in air

    the interference patterns observed in the experiment seemed to discredit the corpuscular theory, and the wave theory of light remained well accepted until the early 20th century, when evidence began to accumulate which seemed to also confirm the particle theory of light

    however what is the best argument against light quanta propagating through aether?

    or... what if light is an energized state of aether, which propagates as waves
    and is also corpuscular in nature?
     
    Last edited: May 20, 2004
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