Res Ipsa Loquitor-- Disproved:The Impossiblity of absolute motion detection.

Discussion in 'Physics & Math' started by geistkiesel, Oct 23, 2004.

  1. Yuriy Registered Senior Member

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    Dear Geistkiesel,
    Let us do this discussion the last one that we have about kinematics of SRT. I promise to be very patient and will answer on all your questions, but you should promise to not try to make me to do your part of job.
    1. Your first sentence is: “For the sake of a simple definition of "absolute velocity" for this particular post, it is the actual velocity that each of two reference frames Va and Vb contributes to the combined relative velocity of two frames.
    Not good definition, because it contains undefined terms “actual velocity”, “contributes” and “combined relative velocity”. Natural Science hates “common sense” definitions. Physics requires that saying “velocity” one does accompany it with specification “in respect to whom?” In case of your first statement you have to say:
    Let us consider two (inertial, if it is essential) reference frames: A and B. Let us (i.e. you immediately specify the observer(s) who describes the picture; if it is essential you should say are “us” inertial observers or "us" are not) see the velocity of A being Va, and the velocity of B being Vb.”
    Without specification of observer the set of words “M has velocity V” is absolutely meaningless.
    Please, remember this rule and follow it in future.
    And after that you can propose your definition of “absolute velocity”. As I am guessing, you try to call the velocity with which A and B move each in respect another as “absolute velocity”. If I am right, you are doing something strange: why the good defined “the relative velocity of two reference frames” should be renamed as “absolute velocity”? Because the velocity with which A and B move each in respect another is called in Physics as “the relative velocity of A and B”. You simply do not like this name by some personal reasons? Why we all should follow you? But personally I am ready to call this velocity as “the absolute velocity of A and B” for this particular post.
    2. So, Va and Vb are the velocities that we (I suppose – inertial observers being in the same reference frame, let
    call it “Laboratory”, or L) see for two inertial systems, A and B respectively, that are moving on the collision course (Let us say – along axis X). Pay attention: A and B, not Va and Vb! A and B are names of reference frames, Va and Vd are the velocities we see for each of them, respectively…
    And now you are saying: “If the two frames are moving in a collision couse wrt each other, Vb moving at 3000 units and Va at 6000 units the combine relative velocity is 9000 units.” I guess, you wanted to say Va=6000 and Vb=3000 units. I guess, you wanted to say: “The velocity that the relative velocity (or according to our agreement for this particular post – the absolute velocity of those two reference frames) will be V = 9000 units."
    Absolutely WRONG!
    In the simplest case when everything happens along axis X of the our reference frame and coordinate axes of all three reference frames are oriented the same, and clocks of all three systems are synchronized at beginning, the observer in A will see B moving with velocity
    (Vb)a = (Vb + Va)/(1+VaVb/c^2)
    and observer in B will see A moving with velocity
    (Va)b = - (Vb + Va)/(1+VaVb/c^2)
    This velocities will be equal by module (i. e observed speeds will be the same) but will be oriented opposite.
    In the more complicated case when everything happens along arbitrary axis, the description will be more complex.
    So, you have to recognize once and forever that velocities do not obey Galilean algebra, they obey SRT algebra (the Einstein’s law of addition of velocities)
    3. All further in your post is what I call an attempt to force me to do your job.
    So, how you accept this my response?
     
    Last edited: Nov 12, 2004
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  3. geistkiesel Valued Senior Member

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    Yuriy,
    Yes, i trust I have described all below as per the agreement. Two ships A and B moving along the X axis with measured relative velocity Va - Ab = 9000 units. A velocity probe A' house on A is released such that the initial measured relative velocity, Va' - Va = 0. Now A' accelerates in the = -x direction and begins to measure the probe relative velocdity wrt A and B in periordic durations of uniform motion and acceleration.

    Finally, the measured relative velocities Va' - Vb = 0. and Va' - Va = 2000 units are reached more or less at the same instant.

    From this A' informs the A and B observers of the measured values (everyone has the same information,

    Va' - Vb = 0 (1)
    Va + (-Va) = 2000 (2)

    As the original relative velocity

    Va - Vb = 90000 (3)

    we subtract (2) - (1)

    Va + (-Vb)) = 2000 the same as (2)

    From this we conclude the measured contributions
    of velocity of A and B to the total relative velocity of the two, measured 9000 units, as


    |Va| = 7000 (4)
    |Vb| = 2000 (5)


    Do you agree that (4) and (5) do represent the
    velocity contributions of each reference frame to the total relative
    velocity of the A and B frame as indicated?


    What would you say if the initial relative velocities of A and B measured from the earth frame E were Va = 7000 and Vb = 2000 (B making a long slow 1/2 circle to change direction)?

    Thanks,

    Geistkiesel

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    Last edited: Nov 12, 2004
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  5. Yuriy Registered Senior Member

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    Dear Geistkiesel,,
    Sorry, but I do not understand some points in your post. They are the following:
    1. In formula
    Va - Ab = 9000 units
    what is Ab?
    2. Now, what is a configuration of all three systems in the moment of launching of A’ from A? It is very important issue for your problem. Please, describe or give a scheme where were all three systems at launching of A’ with marking vectors of their velocities.
    3. Please, do the same also for the moment when we see that system B is in instant rest with A’. When you will do it, your problem will gain a very interesting sense.
    4. I already asked you and I repeat it again: saying velocity is ….always refer to whose velocity and who sees that velocity. Without that information sentence becomes meaningless.
     
    Last edited: Nov 12, 2004
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  7. geistkiesel Valued Senior Member

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    Ab is a typo, should read Va - Vb = 9000 units.

    All three vehicles have radar reflection cabalilities to measure relative velocity with respect to each other.

    A' is just a robot vehicle launched by gently pushing it out from A. At this instant A' is drifting along side A. A' (assumes by programming) to start moving in the rearward direction to A along the -x direction. Here we simply assume A is 'facing' in the direction of the on coming B ship 'assumed' to be also moving in the -x direction. If the B ship were 'moving' in the +X direction same as the A is assumed to be moving, though slower, the A' would detect an increasing relative velocity, Va' - Vb, as it accelerated and then achieved a uniform motion in the -X direction of the B ship. In this case A' would reverse course and start taking measuremnt while moving in the +X direction. Basically, the probe determes the relative directions of motions of the ships and can determine if the Va is > Vb where both move in the +X direction, or whether the ai = -bi where i is the X unit vector of relative motion. The "<- and ->" are assumed directions.

    Code:
      |____| A ->                 [B] +X [/B]--->
    
      |____| A' ->
                                                                        <--s |____|B   
                                                                                            
    Above is the physical orientation, positions of the three vehicles, when A' first released from A and is drifting along side the A ship. Below the relative positions when A' has measured Va' = Vb, and Va' - Va = 2000 units. Obviously the distance is sufficiently large that the positions of separation are as noted, but even if A and B passed each other the measurements would not be affected.

    Code:
                   <-  [B]-X [/B]                    |_____|--->A
               <---|_____| A'                                                   <---|____|B
     
  8. Yuriy Registered Senior Member

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    1,080
    So, Geistkiesel, we are considering the following problem:

    We, being in the Laboratory, L, inertial reference frame, are seeing that
     The inertial system A moves with some velocity Va in positive direction of axis X along it;
     The inertial system B moves with some velocity Vb in negative direction of axis X along it;
     Without specifying values of Va and Vb, we see that A and B are approaching to each other with relative speed Vs = 9000 units. (Pay attention that systems A and B can have the same Vs at absolutely different values of Va and Vb).
     During that approaching, in some moment to of our clock we see as some probe A’ is launching from A without any speed in regard to A and with gently increasing appearing acceleration in the same direction as the approaching B, i. e. in the negative direction of axis X.
     After some time we see the picture like this one
    Axis X --->
    ............................|_____|--->A
    <---|_____| A' ............................................... <---|____|B

    And right there starts something unpredictable in your posts: you make the statement like following one:
    In some moment A’ measures velocities of system A, Va’, and velocity of system B, Vb’, and gets the following values
    Vb’ = 0 and Va’ = 2000 units”.
    This assertion is an important base of all your further investigation.
    But it is absolutely WRONG assertion: there is no such moment and such measurements, giving such values of Vb’ and Va’, in Nature!
    When A’ sees speed of B equal to zero he sees the speed of A equal to 9000 units. Exactly the same value of speed that B sees all the time!
    It is clear without any application of Lorentz transformation, because by the definition any two observers that have zero speed with respect of each other instantly are the same reference frame!
    Think about it. If you disagree, let us discuss this issue before we will go further.
     
  9. geistkiesel Valued Senior Member

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    2,471

    We have no disagreement, I just falterd a bit and should have inserted the word "relative" appropriately above. You had no quarrel with the fact that the A, A' and B systems measure the relative velocities such as Va wrt Vb and vice versus. Likewise, A' is only measuring the relative velocity wrt the B ship and wrt A. There is no claim that any of the frames measure anything other than relative motion, such as the 9000 units.

    The phrase you questioned was poorly written perhaps, so I wil redo the description:

    As A' is measuring the relative velocity wrt B it is also measuring the relative velocity wrt A, the mother ship. Remember A' is moving in the same direction as the B frame. Therefore the relative motion, speed, between them decreases, while at the same time the relative velocity wrt to the A ship increases. Let us assume that when the relative velocity of A' and B is 0, the A' and B are moving in the same direction at the same speed all relative to A. As A' started at zero velocity relative to the A ship and continuously increased the relative velocity, at the instant the A' and B ship is zero, the relative velocity of A' and A is the same as that continuously subtracted by A' as it closed in on the '0' velocity condition wrt B.

    When A' considers the A ship at zero, like when A' started moving initially, A' is continually maintaining and updating the A', A relative velocity. So when A' sees that Va' - Vb = 0, he also sees that the relative Va - Va' = 2000 (there is nothing special about 2000, or any other number, these are just the values mesured simultaneously). This 2000 is just that A', A relative velocity at the instant the A' , B relative velocity is measured as 0, i,e, when Va' = Vb.

    Now as A' communicates the results of its measurments to A and B, each ship knows what each contributes to the relative velocty measured at 9000, Vb contributes 2000 units and Va contributes 7000 units.
    *******************************************************
    Let us take a hypothetical example.

    A accelerates from E, Earth and measures its relative velocity through "triangulation" measurements using 20 stars all of which cannot be distinguished from zero velocity and are located 'spheically' around Earth. The A ship and Earth platforms confirms the same velocity whatever it is.

    Now A having a history of its acceleration deceleates an equal amount to a measured relative velocity of zero wrt earth E, and verifies the accuracy of the deceleration process. B now, goes through the same process from planet Farearth and reaches a relative velocity of 9000 units wrt Farearth using the same star system used by A and E. Farearth and Earth have the same relative velocity wrt the 20 stars (immeasuarbly different from 0), though each is not aware of the other's "existence".

    As B approaches A each detect a relative velocity of 9000 units. The observer on A just woke up and replaced the original observer, on A and is unaware of the deceleration and he knows only that the relative velocity is 9000 units as does his counter part on B who also just woke up knowing nothing about the relative speed achieved by B as it accelerated from Farearth.

    Now we are at a position the same as our example above, as far as the observers are aware. A launches the probe which makes the same measurements as the earlier situation. A' here will accelerate to a velocity of 9000 units wrt A before the relative velocity wrt to B becomes zero. A' radios the information to the A and B observer where each now can say that A is contributing 0 units of relative velocity to the Va - Vb = 9000 relative velocity and that B is contributing all the 9000 units; then each can infer the speed history of the other to be as described and confirmed when the previous observers on A and B, when reviewing the data radioed by A', or relatively speaking, Va = 0 and Vb = 9000.

    I recognize the "possibility" that the universe may be drifting with some speed and direction unknown, unmeasured and unmeasurable, as there are no reference points the universe can use to make any relative measurements.

    At this point I say that any speculative speed/velocity/direction of the universe can be ignored in any theoretical structure for all intents and purposes, and that only measurement resolution, or accuracy, has any physical significance, at this point, and that it would not be counter to any law of physics to say that A is stationary, absolutely, and that B is moving at an absolute velocty of 9000 units.
     
  10. Persol I am the great and mighty Zo. Registered Senior Member

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    It would be just as correct if someone said B was stationary and A was moving... hence the lack of absolute motion.
     
  11. geistkiesel Valued Senior Member

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    2,471
    Persol, your conclusion preceded your nonexistent analysis.

    The relative contribution of each frame A and b would be measured as I stated in my post. It makes no difference which frame you start with.

    The B ship launches a probe B' and begins to accelerate in the -X direction and imediately discovers an increase in relative velocity of B' and A starting from a known relative velocity of 9000 units wrt A and B. B' reverses motion to the +X direction and sees a coresponding decrease in relative velocity wrt A untill that added relative velocity gained during -X motion is completely subtracted. Then as B' measures an increase in relative velocty wrt A (after zeroing out the added velocity) B' concludes the current relative velocity added to the known 9000 unit relative velocity wrt to A and B exceeds the 9000 units measured by both frames. Therefore the only conclusion the B' frame can come to is that A is stationary wrt B.

    In other words if there were two B probes, B' and B'' each moving in opposite directions (B' in the -X , B'' in he +X direction) each would measure increases in relative velocity immedaitely. If B were stationary and the two probes started out the B' probe heading toward A would show an increase in relative velocity while B'' a decrease in relative velocity.
     
  12. Persol I am the great and mighty Zo. Registered Senior Member

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    ...relative to planet A. Relative to B, both cases are identical... regardless of B's speed in relation to A.
     
  13. Yuriy Registered Senior Member

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    1,080
    Dear Geistkiesel,
    So, after last correction your initial statement looks as consisting of 5 sentences and they are the following:
    1.“As A' started at zero velocity relative to the A ship and continuously increased the relative velocity, at the instant the A' and B ship is zero, the relative velocity of A' and A is the same as that continuously subtracted by A' as it closed in on the '0' velocity condition wrt B.
    2. When A' considers the A ship at zero, like when A' started moving initially, A' is continually maintaining and updating the A', A relative velocity.
    3. So when A' sees that Va' - Vb = 0, he also sees that the relative Va - Va' = 2000 (there is nothing special about 2000, or any other number, these are just the values mesured simultaneously).
    4. This 2000 is just that A', A relative velocity at the instant the A' , B relative velocity is measured as 0, i,e, when Va' = Vb.
    5. Now as A' communicates the results of its measurments to A and B, each ship knows what each contributes to the relative velocty measured at 9000, Vb contributes 2000 units and Va contributes 7000 units.”
    Let us analyze it scrupulously.
    1. Here you are saying that:
     A’ started Va’=0. (Va’ is velocity of A in respect to A’)
     A’ is accelerating, and therefore sees Va’ continuously increasing.
     At moment when A’ sees velocity of B equal to 0, i.e. Vb’=0, the Va’ is “the same as that continuously subtracted by A' as it closed in on the '0' velocity condition wrt B.” I do not know what this set of words means, but based on your highlighted statement “There is no claim that any of the frames measure anything other than relative motion, such as the 9000 units” made before it, I assume you are agree that Va’=9000 units at this moment.
    Therefore, your sentence 1 is expressing the right things (in some unusual language).

    2. I guess this sentence is simply grammatically wrong. But by idea, it states that A’ is constantly monitoring (i.e. measuring) the velocity Va’.

    3. And here again comes your amazing jump of logic: you again state that when A’ sees Vb’=0 he sees Va’=2000!!! You even emphasize “there is nothing special about 2000, or any other number”. WRONG, WRONG and WRONG again. Contrary, there is very special with value of Va’ at Vb’=0, At moment when Vb’=0 our observer A’ has to see only the one value of Va’ and this value is 9000 units. Therefore, in sentence 3 you contradict not only with Reality, but with your own highlighted declaration “There is no claim that any of the frames measure anything other than relative motion, such as the 9000 units”.

    Therefore, following sentences 4 and 5 reflect the wrong conclusions. It means that you have to correct your position.
     
    Last edited: Nov 13, 2004
  14. geistkiesel Valued Senior Member

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    2,471
    OK Yuriy, I will correct the statement. When Va' - Vb = 0, the relative velocity Va' - Va = 2000 and this is a relative value of velocity. There is nothing special about the number, it is made up, I meant the statement that any number measured would be relative and the amount subtracted from Vb is the same number that must be subtracted from Va. Nothing special meant that only relative velocities were measured, buth this, of course, gave the absolute numbers by inference. Therefore, Va subtracting 2000 means that Va contributed 7000 units to the total relative value of 9000 as between Va and Vb. The actual numbers of Va and Vb do not change as Va' is the only vehicle making any changes when making the measurements. Va' is actually moving at 7000 units when Va' - Vb = 0. After all, Va' subtracted this amount when coming to the 'at rest' position regarding Va' and Vb. I never intended to say anything other than this. So the bottom line is, for their contribution of each ship's absolute motion,

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    Va = 7000 units
    Vb = 2000 units

    both values being absolute numbers.

    I suppose the numbers generated by the Va' mesurement were very special, reltively speaking, correct?

    Thank you very much Yuriy, you have been vey helpful and very patient in your work. You deserve more than the simple thank you tha I am able to offer.

    Respectfully,
    Geistkiesel.
    I trust this clears the unintended and unambiguous conclusion.
     
  15. geistkiesel Valued Senior Member

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    2,471
    No, read the example again. Both A and B used the same reference points to make measuremenst, though both were unaware of he other's activity. Understand?
    Geistkiesel.
     
  16. Persol I am the great and mighty Zo. Registered Senior Member

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    Which says absolutely nothing about absolute motion.
     
  17. MacM Registered Senior Member

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    Absolute motion of the solar system has been measured 8 times in recent years. It is on the order of 300km/s.

    That would be relative to the bulk of the rest of the universe or a hypothetical absolute space.
     
  18. Persol I am the great and mighty Zo. Registered Senior Member

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    That does not make it absolute motion any more than geist measuring relative to earth is absolute motion.
     
  19. geistkiesel Valued Senior Member

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    If you look closely I defined "absolute" I didn't use the siliness of SR, not after writing the thread. I am confident that whoever reads this, with some obvious exceptions, such present company, will not be opposed to my borrowing the term for my own purposes. It really wasn't a theft not after confessing to the liberation of the word.

    Again, if you look at the reference I used, 20 stars sufficiently at a distance that using their immeasurable motion as an "assumption" of their zero speed for purposses of triangulation measurements, which was used by both the A and B frame, does no insult to the word 'absolute' even for the most rabid SR theorist.
     
  20. geistkiesel Valued Senior Member

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    Last night I saw the 300 km/sec numbers in the UniKEF link. Dayton Miller found 208 km/sec for the helicalwithin helical trajectory of the solar system being dragged along by the sun in the direction of almost "due south" wrt earth. DM also claimed direct agreement with MM who also found 8km/sec of the earth wrt the "ether".

    Here is Miller link I haven seen the original DM paper on he internet, but it is very interesting reading. Thee wasn't a scientist in eh countrythat coukld be considerd more mainstream than DM in the 20s and 30s. Anyway his final paper (describing the result of over 200,000 experiment with the MM interferometer is 1933 h reviews of Modern Pghisc vol 3 203 -243.)

    I did a calulation I thought interesting. The radius of the earth sun orbit is 1.5x10^8 km, which when compared to a one year distance track of the sun, say at 300 km/sec = 300x31465687 = 9.5 x 10^9 or an angle tan-1(.15/9.5) =.9 degrees (orbit radius of (earth/sun)/distance of sun in one year) which is a fairly narrow limitation of the earth trajectory. I did a calculation, almost from sight, that the earth orbit and rotation direction vectors get lost in the mud wrt the sun yearly trajectory.

    I scaled the thing down for a different perspective. If the earth radius was 1 cm the sun diameter would be 109 cm, the earth orbit 233 meter, Mercury 87 meters with the Pluto/Sun orbit radius ~ 9 km. Looking at it this way it seems, more from an intuitive perspective, that one would be hard pressed to ever get an earth/sun orbit scheme going in deep space. When reading the treatise describing "gravity" being stronger than the standard model of inverse square of the distance, at large distance, this gives a much more credible reality to the story.

    I also have this "recurring dream" of gravity being mistaken for what is basically a "conservation of angular momentum process". One cannot discard the angular momentum out of hand and omit all angular momentum contributions to stellar orbiting dynamics.

    The sun has ~ 10^3 the mass of the solar system combined, yet only a percent or so of the total angular momentum of the solar system.
     
  21. geistkiesel Valued Senior Member

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    See below. I defined the "absolute" motion, so if you are using SR theory for your misunderstanding, you might want to reconsider your statement, which really says nothing, absolutely nothing.
     
  22. Persol I am the great and mighty Zo. Registered Senior Member

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    But depending on what group of stars you choose there IS relative measurable motion. Regardless, using these as your V=0 means absolutely nothing and provides just as much.

    Don't use the term absolute for meaning 'based on my arbitrary decision.
     
  23. geistkiesel Valued Senior Member

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    Just to be sure that I am not lost in the translation, the sentence above means that the original 9000 units was a measure of relative motion, only; also the measurement of Va' - Vb - 0 is relative motion; and finaly Va - Va' = 2000 units when Va' -Vb = 0, which was measured also as relative motion. Therefore, goes the logic, scaled back to a teeny tiny step, the contributions of motion to the total relative motions, albeit they be inferentially determined, of Va and Vb are,

    Va contribution = 7000 units and the
    Vb contribution is 2000 units,

    which I now state unambiguously are two measured velocities of absolute motion.

    And again thank you for your patience; I "owe you one" , as the saying goes.

    Geistkiesel.

    I trust this further clears the unintended conclusion read by yourself
     

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