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Did Einstein accept the Ether

  1. Jul 18, 2003 #1

    selfAdjoint

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    Mr. Robin Parsons and I were discussing this issue on another thread. He claims sources show that Einstein confessed his belief in the "aether" after 1919 and thereafter held to that view. I showed him an Einstein quote from 1920 in which E. said "The aether of the general theory of relativity is a medium without mechanical and kinematic properties, but which codetermines mechanical and electromagnetic events." (Source, Pais, "Subtle is the Lord" p 313.) I claimed this shows the word aether for Einstein cannot mean the mechanical and kinematic ether that its proponents claim he supported.

    Mr. Parsons declined to be persuaded so I went to the online Einstein Archives and looked up aether. This is what I got. The documents are handwritten in German and I cannot read German script. Perhaps someone on this board can? A little translation help could settle a great dispute.

    Thanks.
     
  2. jcsd
  3. Jul 18, 2003 #2
    i don't see how mr. parsons could deny it. einstein was the first person to ever deny the existance of an ether back while he was a nobody working in a patent office.
     
  4. Jul 18, 2003 #3
    as i remember einstein didnt deny the possibility of ether he just said it wasnt necessary to be implemented.
     
  5. Jul 18, 2003 #4
    Hi selfAdjoint,
    I can decipher & translate Albert's handwriting, but please tell which of the documents in the list you want translated.
     
  6. Jul 18, 2003 #5

    selfAdjoint

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    Great! Why not start with the first one "Ueber den Aether" is I have remembered correctly. Then one or the other of the three documents from 1930 with titles like On the Space-Aether and Field problem, in my lame translation. But first things fiorst. What does he say in the first document?

    And thanks much for your kind offer!
     
  7. Jul 19, 2003 #6
    OK, here goes...

    GERMAN:

    Über den Aether.
    Wenn hier vom Aether die Rede ist, so soll es sich natürlich nicht um den körperlichen Aether der mechanischen Undulationstheorie handeln, welcher dem Gesetz der Newton'schen Mechanik unterliegt, und dessen einzelnen Punkten eine Geschwindigkeit zugeteilt wird. Dies theoretische Gebilde hat nach meiner Überzeugung mit der speziellen Relativitätstheorie seine Rolle endgültig zu Ende gespielt. Es handelt sich vielmehr allgemein um diejenigen als physikalisch-real gedachten Dinge, welche neben der aus elektrischen Elementarteilchen bestehenden ponderabelen [sic] Materie im Kausal-Nexus der Physik eine Rolle spielen. Man könnte statt vom "Aether" also ebensogut von "physikalischen Qualitäten des Raumes" sprechen. Nun könnte allerdings die Meinung vertreten werden, dass unter diesen Begriff alle Gegenstände der Physik fallen, weil nach der konsequenten Feldtheorie auch die ponderable Materie bzw. die sie konstituierenden Elementarteilchen als "Felder" besonderer Art bzw. als besondere "Raum-Zustände" aufzufassen seien. Indessen wird man zugeben müssen, dass beim heutigen Zustande der Physik eine solche Auffassung verfrüht wäre, denn bisher sind alle auf dies Ziel gerichteten Bemühungen der theoretischen Physik gescheitert. So sind wir beim heutigen Stand der Dinge faktisch gezwungen [sic: no comma] zwischen "Materie" und "Aether" zu unterscheiden, wenn wir auch hoffen dürfen, dass spätere Generationen diese dualistische Auffassung überwinden, und durch eine einheitliche [sic] ersetzen werden, wie es die Feldtheorie in unseren Tagen vergeblich versucht hat.
    Man glaubt gewöhnlich, dass die Physik Newtons keinen Aether gekannt habe, sondern dass erst die Undulationstheorie des Lichtes ein allgegenwärtiges, die physikalischen Phänomene mit-bedingendes Medium eingeführt habe. Dies ist jedoch nicht der Fall. Die Newton'sche Mechanik hat ihren "Aether" in dem angedeuteten Sinne, der allerdings als "absoluter Raum" bezeichnet wird. Um dies klar zu erkennen und gleichzeitig den Aether-Begriff etwas schärfer herauszuarbeiten, müssen wir ein wenig ausholen.
    Wir betrachten zuerst einen Zweig der Physik, der ohne Aether auskommt, nämlich die Geometrie Euklids, aufgefasst als die Lehre von den möglichen Arten, praktisch starre Körper miteinander in Berührung zu bringen. (Von den Lichtstrahlen, die ebenfalls bei der Entstehung der Begriffe und Sätze der Geometrie beteiligt sein mögen, sehen wir hier ab.) Die Lagerungs-Gesetze fester Körper bei Ausschluss von relativen Bewegungen, Temperatur [sic] und Deformationseinflüssen, wie sie idealisiert in der Geometrie Euklids wiedergelegt sind, kommen mit dem Begriff des starren Körpers aus; irgend welche Milieu-Einflüsse, die als unabhängig von den Körpern vorhanden und als auf die Körper wirkend und ihre Lagerungs-Gesetze beeinflussend gedacht würden, kennt die euklidsche Geometrie nicht. Dasselbe gilt von den nicht-euklidschen Geometrien konstanter Krümmung, wenn diese als (denkbare) Naturgesetze der Körper-Lagerung aufgefasst werden. Anders wäre es, wenn man eine Geometrie variabler Krümmung anzunehmen sich genötigt sähe; dies würde bedeuten, dass die Gesetze der möglichen Berührungs-Lagerungen von praktisch-starren Körpern in verschiedenen Fallen [sic] verschieden, von Milieu-Einflüssen bedingt wäre [sic]. Hier müsste man im Sinne unserer Betrachtung sagen, eine solche Theorie bediene sich einer Aether-Hypothese. Ihr Aether wäre etwas physikalisch-Reales [sic], so gut wie die Materie. Wären die Lagerungsgesetze durch physikalische Faktoren, wie Anhäufung und Bewegungszustand von Körpern in der Umgebung etc. nicht beeinflussbar, sonden unverrückbar gegeben, so würde man diesen Aether als "absolut", d.h. von Einflüssen in seiner Beschaffenheit unabhängig bezeichnen. -
    Ebensowenig wie die euklidsche (physikalisch-interpretierte) Geometrie einen Aether braucht [sic: no comma] ebensowenig bedarf die Kinematik oder [???] der klassischen Mechanik eines solchen; ihre Sätze haben einen klaren physikalischen Sinn, wenn nur angenommen wird, dass die in der speziellen Relativitätstheorie angenommenen Einflüsse der Bewegung auf Uhren nicht existieren.
    [big cross-out]
    Anders in der Dynamik Galileis und Newtons. Das Bewegungsgesetz "Masse . Beschleunigung = Kraft" enthält nicht nur eine Aussage über materielle Systeme, auch dann nicht, wenn wie bei Newtons astronomischem Fundamentalgesetz die Kraft durch Abstände, d.h. durch Größen ausgedrückt ist, deren Realdefinition auf Messungen mit starren Messkörpern gegründet werden kann. Denn die Realdefinition der Beschleunigung kann nicht restlos auf Beobachtungen an starren Körpern und Uhren gegründet werden. Sie kann nicht zurückgeführt werden auf die messbaren Abstände zwischen den das mechanische System konstituierenden Punkten. Man bedarf zu ihrer Definition noch eines Koordinatensystems bzw. Bezugskörpers von geeignetem Bewegungszustand. Wird das Koordinatensystem anders gewählt, so gelten in bezug auf dasselbe die Newton'schen Gleichungen nicht.
    [I'm tired now. To be continued & translated ...]
     
  8. Jul 20, 2003 #7
    Wasn't Einstein actually the one who PROVED ether doesn't exist?
     
  9. Jul 20, 2003 #8

    jcsd

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    The existance of the ether was disproved by the Michelson-Morley experiment in 1887 (a rehash of an experiment performed in 1881 by Micelson, which he initially rejected due to this radical result) when Albert Einstein was only 8 years old.

    The non-existance of the ether allowed Albert Einstein to formulate his theory of special reltivity
     
  10. Jul 20, 2003 #9
    What you have to remember is that Rob argues even if it is blatently obvious that he is wrong.

    WOOHOO! 100 posts.
     
    Last edited: Jul 20, 2003
  11. Jul 20, 2003 #10
    The Michelson-Morely experiment was ONE of the methods employed to Dis-prove the existence of the Ether, the Other test results came from Sir Oliver Lodge's experimentation.

    He tested a second method for finding evidential Etherial activity, he too found No Evidence, in his proposed, and tested, method.

    They both missed out on the 'third alternative' to a methodological proof.
     
  12. Jul 20, 2003 #11

    jcsd

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    The Michelson-Morley experiment can be seen as the end of the ether as the medium of propagation for em waves and it's results have been proven again and again using different method. Michelson was not trying to disprove the ether, he was merely trying to detect it and as I alluded to earlier had rejected results from an experiment he performed a few years earlier due to the fact they disproved the ether.
     
  13. Jul 20, 2003 #12

    jcsd

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    I should make it clearer, Robyn. For all theories the results need to be independantly verified, but any discussion of the exp. evidence for the etherwill utimately centre aroung the M-M exp.
     
  14. Jul 20, 2003 #13
    So you don't think that there is any other possible explanation possible, good for you.

    Seek not, and ye shall find not.
     
  15. Jul 20, 2003 #14

    jcsd

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    No, but I prefer to stick with Occam's razor and take the explanation that fits the eveidence the best.
     
  16. Jul 20, 2003 #15
    So do I!
     
  17. Jul 20, 2003 #16
    OK, since so much is going on here, I will post my translation of the 1st part now, and then let's see if any more is needed.

    ENGLISH (my translation):

    Concerning Ether.
    If we talk about ether here, then of course we don't talk about the bodily ether of the mechanical theory of undulation, which obeys the law of Newton's mechanics, and whose single points have velocities assigned to them. This theoretical construct has, in my opinion, found its definite end in the special theory of relativity. Instead, we talk about those things considered as physically-real, which, apart from ponderable matter consisting of electrical elementary particles, play a role in the causal nexus of physics. Instead of 'ether', we could as well talk about 'physical qualities of space'. Well, one could be of the opinion that this definition applies to all objects of physics, because according to strict field theory, also the ponderable matter (i.e. the elementary particles that constitute it) can be considered as 'fields' of a special kind, i.e. as special 'states of space'. However, one will have to admit that, in the current state of physics, such an opinion would be premature, because all effort of theoretical physics directed at this goal, has so far been in vain. As things are today, we are factually forced to discriminate between 'matter' and 'ether', but we may hope that later generations will overcome this dualistic picture and replace it with a uniform field theory, as field theory in our day has tried in vain.
    It is generally believed that Newton's physics have known no ether, but that only the undulation theory of light has introduced an omnipresent medium which co-influences physical phenomena. But this is not so. Newton's mechanics has its 'ether' in the proposed sense: It is called 'absolute space' there. To recognize this clearly and, in doing so, define the concept of ether more clearly, we must go deeper into the subject.
    Let's first look at a branch of physics which manages without ether, namely Euclid's geometry, interpreted as the theory of possible ways to bring practically rigid bodies in contact with each other. (Let's not consider light rays, which may also play a role in the genesis of geometrical conceptions and theorems). The laws of storage of rigid bodies, if we exclude relative motion, temperature and influences of deformation, as they are laid down in an idealized way in Euclid's geometry, only need the concept of the rigid body. Any influences from the environment, which are there independently of the bodies, and are thought of as acting on the bodies and affecting their laws of storage, are unknown to Euclid's geometry. The same is true of the non-Euclidean geometries of constant curvature, if these are interpreted as (imaginable) natural laws of body-storage. It would be different, if we were forced to assume a geometry of variable curvature. This would mean that the laws of possible contact-storages of practically rigid bodies would be different in different cases: Conditioned by influences from the environment. In this case, one would have to state in the sense of our line of thought that such a theory would use an ether-hypothesis. Its ether would be something physically-real, as good as matter. Would the laws of storage be inert to physical factors, auch as accumulation and state of motion of bodies in the vicinity, but given unchangeably, then we would call this ether 'absolute', i.e. independent in its structure from any influences.
    As little as Euclid's (physically interpretable) geometry needs an ether, as little do kinematics or [???] in classical mechanics need one. Their laws have a clear physical meaning, if only we accept that the influences of motion on clocks, which are proposed in special relativity, don't exist.
    [big cross-out]
    Things are different in Galilei's and Newton's dynamics. The law of motion 'mass x acceleleration = force' not only contains a statement about material systems, not even if, as in Newton's astronomical fundamental law, force is expressed by distances, i.e. quantities whose real definition is based on measurements with rigid bodies. This is because the real definition of acceleration can not completely be reduced to observations of rigid bodies and clocks. It can not be reduced to measurable distances between points which constitute the mechanical system. For a proper definition, you also need a frame of reference, i.e. a reference body, of appropriate state of motion. If you choose another frame of reference, then Newton's equations are not valid with respect to that frame of reference.
     
  18. Jul 20, 2003 #17

    selfAdjoint

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    Thank you so much! This is exactly what we need.

    Now Mr. Robin Parsons, can we agree that Einstein wrote this:

    and therefore that he did not believe in the luminiferous ether?
     
  19. Jul 20, 2003 #18

    Eh

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    I gave this URL to a crank on these boards who was claiming GR requires an aether: http://math.ucr.edu/home/baez/RelWWW/wrong.html#aether

    From the site. Text in red is mine:

    .....This claim (that GR is an aether theory) is misleading, to say the least. What Einstein really meant was that the aether which had been overthrown by str (and thus was incompatible with gtr, which incorporates str) involved a a specific ``preferred frame of reference'' in the classical field theory, whereas the field equation of gtr involves no ``prior geometry'' (such as the euclidean geometry of ``space'' which has assumed by Maxwell and his contemporaries), much less any ``preferred frame''. Nonetheless, gtr does not quite say there is ``nothing'' in ``empty space''; in general there will be gravitational waves running about, and these carry (very tiny) amounts of energy, which gravitate. So in this sense, a very different kind of ``aether'' in the very weak sense of there being ``something there'' in a vacuum (namely nonlocalizable gravitational field energy, metric properties of ``space'' in a 3+1 decomposition, etc.), could be said to enter into gtr.....
     
  20. Jul 21, 2003 #19
    And from this aspect, it is still accepted as a thought/nomenclature for the division of matter and space....it is as I had stated some time back, Argot.

    The only difference is that you do not accept my terminology, because my terminological inference contains elements of understanding the you do not have yet. (And you don't like that I hide it that way??!!)

    Ask Greg for a copy of PF 2.0, ($20.00 "CHeeP" said the 'boird') then see my postings in the subject/thread "The Prefferred Frame" (Misspelt too!)
     
  21. Jul 21, 2003 #20

    selfAdjoint

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    OOOh! "Argument weak - use colored chalk". And then retreat into arcana. Nobody can criticise Mr. Parsons' statements because they have secret meanings the rest of us don't know.
     
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