Thread: Mac's Final Relativity Thread

  1. #301
    Registered Senior Member MacM's Avatar
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    Quote Originally Posted by James R View Post
    No flaws have been found in 100 years.
    Only because you refuse to look. Just over adecade after SR Einstien concluded that it was via his GR view that the Twin Paradox was resolved.

    You on the other hand want to continue to claim that reciprocity is physically real. You want to deny that to consider frame switching is no longer computing mere relative veloicty.

    Sorry you are wrong but just refuse or are to stupid to know it.

    BTW: I don't appreciate having to call you out for your ignorance but since you seem to enjoy implying so toward me it is appropriate that I recipocate.

    I notice you have not commented on the radioactive clocks being compared in the "A" & "C" frames with the same result.

    Or the car/radar analogy showing a slow watch accounts for trip time not a change in distance. Even if you want to claim both cars going side by side went less distance their respective clocks recorded less time and hence you still have a problem.

  2. #302
    Please use Sugar Cane Alcohol Billy T's Avatar
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    Quote Originally Posted by Quantum Quack View Post
    All I am attempting to do to be honest is to "narrow" down MacM's complaint against SRT so that it can be debated properly without all the fudge , inuendo and bullshit that flys about on occassion.
    That is desirable and I too avoid character attacks etc. but think it necessary to get MacM to precisely define what is "MacM SR."

    After several posts asking for calrifications, I tried to summarize MacM SR in post 92 and MacM agreed with that in post 93. Back then MacM had faith (and I think still does) in the use of time dilation formula that Standard Sr does for the clock which had earlier left the common rest frame. And also back then in computing the time dilation, TD, between two clocks, A & B by separately computing their TDs from their last common rest frame and subtracting these TDs to get their relative TD, but after I showed that was a self contradiction in case where both methods could be applied (in post 118), MacM changed his POV and said that he did not know how to compute that TD but SR did not either. So I am now trying to get MacM to used more precise than words only i.e. symbols to clearly define varialbles instead of just assert / assume that there is what standard SR states does not exist. I.e.not assume one physical Time Dilation for all frames and then conclude that there exist one physical time dilation for all frame so Standard SR is wrong as well as not fully tested.

    If you agree Macm needs to be more clear and keep to one verions, help me pin him down to what pricisely that is.

  3. #303
    Registered Senior Member MacM's Avatar
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    Quote Originally Posted by Billy T View Post
    ...., but after Ishowed that was self contradiction in case where both methods could be applied (in post 118) MacM chaged is POV and sdie that he did not know how to compute th at TD but Sr did not either.
    Keep it honest. I have not changed my POV I have always said a simple absolute view does not work. You haven't pointed out anything I didn't already know.

    What I'm pointing out is that SR can't either and if SR is invalid it means somethingelse is happening. I am merely suggesting other possibilities even though the simple view doesn't answer all questions either it at least eliminates numerous BS consequences of SR.

  4. #304
    Please use Sugar Cane Alcohol Billy T's Avatar
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    MacM it is past my bed time so will be quick. I said SR Theory does not use require or applie to non-inertial frame cases. that is not the same as asserting it is correctr discription of realitiy. It is a simple statment about the theory. Where in the eqution of SR does any acceleration appear?
    I will admit that for some case some one may have extended SR theory to allow it to be applied with small acclerations and little error or to slowig rotating frames etc. I do not know if that is the case or not but extended SRt is not SRT so my statment stands.

    Refute it if you can by showing an equation of SR that includes an acceleration term.

  5. #305
    Quote Originally Posted by Billy T View Post
    That is desirable and I too avoid character attacks etc. but think it necessary to get MacM to precisely define what is "MacM SR."

    After several posts asking for calrifications, I tried to summarize MacM SR in post 92 and MacM agreed with that in post 93. Back then MacM had faith (and I think still does) in the use of time dilation formula that Standard Sr does for the clock which had earlier left the common rest frame. And also back then in computing the time dilation, TD, between two clocks, A & B by separately computing their TDs from their last common rest frame and subtracting these TDs to get their relative TD, but after I showed that was a self contradiction in case where both methods could be applied (in post 118), MacM changed his POV and said that he did not know how to compute that TD but SR did not either. So I am now trying to get MacM to used more precise than words only i.e. symbols to clearly define varialbles instead of just assert / assume that there is what standard SR states does not exist. I.e.not assume one physical Time Dilation for all frames and then conclude that there exist one physical time dilation for all frame so Standard SR is wrong as well as not fully tested.

    If you agree Macm needs to be more clear and keep to one verions, help me pin him down to what pricisely that is.
    actually BillyT I think the issue has already been pretty much nailed down and as yet there has been no adequate response. refer to post #291
    and as your later posts are starting to reflect SRT does not adequately deal with accellerating frames with out mixing theories....as far as I know.
    However the gendanken suggested obviously can't apply SRT and that is part fo the problem. Which gendanken can use SRT and what can't.

  6. #306
    the bottom line is from what I see, any thought experiiment that involves acceleration will not allow SRT to function adequately and I am surprised that this is not mentioned by JamesR and Pete from the very begining of this thread.
    The gedanken of two observers and a pack of explosives is a great point in question. Why would you think SRT could apply to this gedanken when it obviously can't?
    And MacMs clock gedanken seems to be very much the same or at least trying to show the same point.

  7. #307
    MacM:

    Special relativity is based on only two postulates:

    1. The laws of physics take the same form in all inertial frames.
    2. The speed of light is the same in all inertial frames, regardless of the speed of its source.

    Everything else that SR says is a derived consequence of these two postulates. If there is anything wrong with SR, then it must come back to a problem with one or both of the postulates. There is no alternative. It is not possible that parts of SR are correct and other parts are wrong, unless one or both of the postulates above is wrong.

    In particular, it is not possible that reciprocity is wrong unless one or both of the postulates is wrong. It is not possible that length contraction is wrong unless one or both of the postulates is wrong. Velocity dilation cannot be correct unless one or both of the postulates is wrong, etc.

    Unless you address this issue head on, you're really just wasting everybody's time.

    Now, in this thread you have made a claim that you think that maybe postulate 2 is wrong. In fact, if your velocity dilation concept is correct, then postulate 2 presumably must be incorrect, since the speed of light relative to different observers cannot be the same if MacM fantasyphysics velocity dilation is correct.

    Perhaps a good next step would be to give a formula by which you believe the speed of light can be calculated for different reference frames. Do you have such a formula?

    To make this concrete, let's say clocks A and B start together, and B accelerates away to 0.6c. What is the speed of light measured by B after the acceleration, and what formula does B use to calculate it?

    Quote Originally Posted by MacM
    You want to deny that to consider frame switching is no longer computing mere relative veloicty.
    I have no idea what you're talking about here.

    I notice you have not commented on the radioactive clocks being compared in the "A" & "C" frames with the same result.
    I have no idea what you're talking about here. It doesn't matter if a clock is a pendulum clock or a digital clock or a radioactive clock or a heartbeat. Relativity applies equally to all clocks.

    Or the car/radar analogy showing a slow watch accounts for trip time not a change in distance. Even if you want to claim both cars going side by side went less distance their respective clocks recorded less time and hence you still have a problem.
    I have no idea what you're talking about here.

  8. #308
    Quote Originally Posted by Quantum Quack View Post
    the bottom line is from what I see, any thought experiiment that involves acceleration will not allow SRT to function adequately and I am surprised that this is not mentioned by JamesR and Pete from the very begining of this thread.
    That's because it is bullshit.

  9. #309
    Quote Originally Posted by James R View Post
    That's because it is bullshit.
    and there in lies half the problem.

    refer you to post #291
    and go for it show how frame dependent accelleration doesnt pose a significant problem for SRT.'

    because accelleration of only one observer creates a pseudo preferred frame and thats the problem. [a frame that has accellerated is very differnet to a frame that hasn't accellerated or do you dispute this point and claim it bullshit as well?

  10. #310
    QQ:

    Response to #291:

    Say we are in deep space and we have two observers with clocks attached. They are positioned back to back and in between them is a charge of special explosive material [ most likely a substance derived from ancient nuclear stockpiles - just to add color]
    The ensuing explosion accelerates both observers equally and to an eventual separating velocity of .6c
    Is the 0.6c the speed the observers measure each other to have, or the speed relative to the initial frame where they are stationary relative to each other?

    By just applying common sense:

    Which clock is dilated?
    In which frame?

    Are any of their clocks out of synch given that they are sharing the same acquired velocity from a point of rest?
    Out of synch with what?

    have they ever broken their innitial inertial state? [ assuming perfection in accellerations and resultant velocity?
    Accelerations are non-inertial, so both observers have experienced some non-inertial motion.

    Now apply SRT and ask the questions again....
    I just did.

    and you will get entirely different answers...
    What?

    so how is this reconciled, Reality vs SRT?
    You'll have to explain to me how your version of "reality" differs from the answers I have given above.

    The only reason SRT would HAVE to be used is due to the need to support the NOTION that light travels invariantly across vacuum and to maintain that invariance of a TRAVELLING light wave or particle one observer has to be deemed capable of stating he is at rest relative to the other observer and NOT just to himself. If you DON'T apply SRT light is no longer invariant in its presumed Travelling.
    I have no idea what you're trying to say here. Try again?

  11. #311
    IMO the problem is not SRT as SRT is the only possible outcome that can accmmodate postulate 2. The problem lies in that postulate not in SRT which has been purpose built to accommmodate that postulate. Regardless of how ridiculous the SRT outcome is if postulate 2 holds in it's current form SRT must be correct.
    So argueing about SRT is a waste of time as it is the postulate that is at the heart of the problem.

  12. #312
    Quote Originally Posted by QQ
    a frame that has accellerated is very differnet to a frame that hasn't accellerated or do you dispute this point and claim it bullshit as well?
    What's a "frame that has accelerated"? That sounds like a meaningless construction to me.

    Do you know what a (reference) frame is?

  13. #313
    QQ:

    So argueing about SRT is a waste of time as it is the postulate that is at the heart of the problem.
    Are you claiming, then, that the speed of light is not the same in all inertial reference frames?

    If so, can you give me a formula for calculating the speed of light in different frames, as I asked MacM above?

  14. #314
    Quote Originally Posted by James R View Post
    QQ:

    Response to #291:



    Is the 0.6c the speed the observers measure each other to have, or the speed relative to the initial frame where they are stationary relative to each other?
    the .6c is the velocity of separation. The initial frame is non-exstant since the explosion.

    Which clock is dilated?
    In which frame?
    take your pick as it doesnt matter as both observers accellerated at exactly the same rate and are effectively still inertial even after accelleration. In fact they never became non-inertial as far as I can tell.


    Out of synch with what?
    with each other....



    Accelerations are non-inertial, so both observers have experienced some non-inertial motion.
    except if both observers are accelrating in synch with each other so that at no time is one observer at any different velocity when compared to the other. So their relative velocity is always zero just traveling in opposite directions.

    Now if you apply SRT you have a situation where one clock is dilated and only one observer has the .6c instead of both having .3'c'
    You have to do this to ensure that postulate 2 is adhered to yet there is no dilation present between observers as they both shared the exact same acceleration.

    Thus by applying acceleration as is usually the case to only one observer you break symmetry. Leading to discussions that go nowhere fast.
    The reason why I created this gedanken is that accelleration is applied to both observers simultaneously, which maintains symmetry. Yet SRT demands asymmetry of acceleration to function.

    Because reality in this case means that no dilation is present in comparison between observers yet the postulate 2 will demand that there be dilation in only one of the clocks to support invariance of light
    [I am in a cafe and it's a noisy environ so I may have to type this in a better way later]

  15. #315
    Quote Originally Posted by James R View Post
    QQ:



    Are you claiming, then, that the speed of light is not the same in all inertial reference frames?

    If so, can you give me a formula for calculating the speed of light in different frames, as I asked MacM above?
    ha...the problem is not that light or energy is not invariant as i believe it certainly is. The problem is that light,photons/em do not travel across vacuum to get where they are going so light speed invariance only applies to objects of mass and is a fundamental of what mass and I might add inertia is and is not traveling across vacant space vacuum.
    So I have a greater issue with supplying a solution yes?

    Light does not travel...across three dimensional space.....

    So no the problem is bigger than just comming up with another way of accommodating a mythical traveling photon.
    Last edited by Quantum Quack; 07-20-09 at 01:10 AM.

  16. #316
    If two observers are accellerating in synch with each other at exactly the same rate what reference frame terminology would you refer to them as?

  17. #317
    QQ:

    the .6c is the velocity of separation. The initial frame is non-exstant since the explosion.
    You don't seem to understand what a reference frame is. A reference frame is a coordinate system. It is not the same as an observer. It is not the same as an object. You can think of it as an imaginary (3D) grid of rulers that cover the whole of space, where at every spatial location there is also a clock. All the clocks in a particular reference frame tick at the same rate and are synchronised always.

    Frames do not have to be attached to objects. Objects can and often do move within reference frames.

    Quote Originally Posted by QQ
    Which clock is dilated?
    Quote Originally Posted by JR
    In which frame?
    take your pick as it doesnt matter as both observers accellerated at exactly the same rate and are effectively still inertial even after accelleration. In fact they never became non-inertial as far as I can tell.
    You don't seem to understand what "inertial" means. An inertial frame is one that is moving at constant velocity. If it is accelerating, it isn't inertial.

    except if both observers are accelrating in synch with each other so that at no time is one observer at any different velocity when compared to the other. So their relative velocity is always zero just traveling in opposite directions.
    60 km/hr west is a different velocity from 60 km/hr east, which is different from 60 km/hr north-east. Velocity is a vector - it has magnitude (which physicists refer to as "speed") and direction.

    The relative velocity of your two observers travelling in opposite directions at speed v is not zero, but 2v.

    Now if you apply SRT you have a situation where one clock is dilated and only one observer has the .6c instead of both having .3'c'
    I don't know what you mean by this.

    The reason why I created this gedanken is that accelleration is applied to both observers simultaneously, which maintains symmetry. Yet SRT demands asymmetry of acceleration to function.
    No. SRT doesn't even mention acceleration. It deals with inertial reference frames, which are frames travelling at constant velocity.

    ha...the problem is not that light or energy is not invariant as i believe it certainly is. The problem is that light,photons/em do not travel across vacuum to get where they are going...
    When you switch on the light in your lounge room, how do photons get from the light to your eye, if they do not travel to get where they are going?

    Light does not travel...across three dimensional space.....
    How does it get from place to place, then?

    If two observers are accellerating in synch with each other at exactly the same rate what reference frame terminology would you refer to them as?
    That question makes little sense to me. I could view them from an inertial frame, in which case I'd just say they were both accelerating at the same rate. Or, I might view them from a frame that is accelerating with them, in which case I'd say that they are not moving. Or I could choose some other frame.

  18. #318
    damn hard to put in a lingo that makes sense to you sorry....
    The issue is not so much velocity it is dilation.

    if both observers have acheievd a velocity of .3'c' regardless of direction then they should not have any dilation present between them. correct?

    However as you have suggested they are treated as if at relative velocity so they can be given the usual SRT treatment, which will not agree with actual reality based results as both observers will have identicle tick rates. [ I don't see how opposite vectors will effect dilation nor contraction.]

    maybe thats what I need to find out....eh?

  19. #319
    Robbing the Shalebridge Cradle CptBork's Avatar
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    Quote Originally Posted by MacM View Post
    Don't be a twit. I've likely been around SR longer than yourself and I know full well that they have given themselves an escape goat by claiming it only applies to moving through space and not space expansion or contraction.
    1) It doesn't matter to me how long you've "been around" SR, if you haven't worked out the details and done the calculations, you haven't studied it, you've only glanced at it.

    2) I don't know what an escape goat is, but where can I buy one?

    Physicists don't claim SR only applies to motion through time and space. SR is what the title says, Special Relativity- a special case of the more general theory known as GR, specifically the case in which the spacetime metric is Minkowskian, i.e. gravity is absent.

    Quote Originally Posted by MacM View Post
    The problem with that is that SR claims to produce contraction (and hence expansion if decelleration is involved) so you are left with "We will pick what physics we want to recognize" syndrome.
    Like I already said, SR doesn't say anything whatsoever about cosmology.

    Quote Originally Posted by MacM View Post
    Such as the assertion that particle entanglement doesn't violate the v=c restriction because no information is transferred. What a load of self serving crap that is.

    1 - You assume to know that partricles can communicate and don't do so by sharing information.

    2 - For one particle to know the condition of another andthat it has changed it clearly requires the transfer of information.

    You people are pathetic when it comes to making excuses to protect your flawed theory.
    Looks like you never even bothered to ask what physicists mean by information. Faster than light signals can be exchanged between particles to produce statistical correlations between them. Those statistical correlations can only be spotted by exchanging and comparing the results at lightspeed or less, the usual ways. Because the quantum signal is chosen at random and not determined by the experimenters, the experimenters can't produce any controllable effects that would propagate faster than c, travel back in time and cause paradoxes. When we say information doesn't travel faster than c in quantum mechanics, we mean information that the experimenters can actually access and control.

    Quote Originally Posted by MacM View Post
    He claimed "Relative Velocity" causes phsyical changes and published SR but when it was pointed out that reciprocity results in the "Twin Paradox" he over a decade later came out with GR and then said the twin that switched frames broke the symmetry.
    This just proves what I was asserting earlier, you haven't properly studied SR, you're barely aware of the essential details. GR was introduced to explain gravity, that was the only reason Einstein needed it. SR handles accelerations just fine, you treat it by moving through a consecutive sequence of inertial reference frames, each frame moving at a different velocity. There are at least two easy ways I've seen of resolving the twins paradox using only basic SR reasoning. I wrote one of them up here about a year ago (see link). Einstein himself solved the paradox and used it as a means of illustrating the way SR is used and some of the counterintuitive results it describes. The conclusion is the same regardless of what method you use to solve it: the astronaut who went out into space comes back younger than his twin. The biggest thing newcomers forget when trying to show a contradiction in SR is that not only do you have to include time dilation in your calculations, but relative simultaneity also comes into play.

  20. #320
    Quote Originally Posted by Quantum Quack View Post
    if both observers have acheievd a velocity of .3'c' regardless of direction then they should not have any dilation present between them. correct?
    Wrong.

    If A is travelling at 0.3c west and B is travelling at 0.3c east, then the velocity of A relative to B is 0.55c west and the velocity of B relative to A is 0.55c east. Therefore, A's clocks will run slow in B's frame, and vice versa.

    However as you have suggested they are treated as if at relative velocity...
    There's no "as if" about it. They have a relative velocity. Velocity is NOT the same as speed. Direction matters. And that's not relativity talking - it's basic week 1 undergraduate physics.

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