The Relativity of Simultaneity

Discussion in 'Physics & Math' started by Motor Daddy, May 12, 2010.

  1. Neddy Bate Valued Senior Member

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    2,548

    Oh, okay. I thought you were implying that you could detect motion by measuring torque in a drive shaft.

    Anyway, do you agree that the red times shown in my Embankment drawings match the times you calculate using your method?
     
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  3. James R Just this guy, you know? Staff Member

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    Motor Daddy:

    No you can't, because you don't have a clue how force, acceleration, torque, work etc. transform from one frame to another in Einstein's universe.

    No. I can do all of that if required.

    If you're sitting on top of the fan, you observe the room rotating around you. That's called the reference frame of the fan. See?

    No. It's the real world. Note, however, that "motion" comes in different flavours. Sticking to special relativity, we can't distinguish constant relative motion. We can distinguish accelerations.

    With respect to what? The room? I have no argument with that? The floor? I have no argument with that. Absolute space? Such a thing does not exist.

    It's interesting that you bring this up. You do realise that even concepts such as energy are relative, do you not? And that applies in the Motor Daddy universe as much as it does in Einstein's.

    Yes, in your world.

    Correct. So what? If that's the way the world works, that's the way it works. No point tilting at windmills. Get used to reality.

    No. Durations of time are frame-dependent in the real world.

    I've never pretended that objects don't have motion. Motion is frame-dependent, that's all. It's even frame-dependent in the Motor Daddy universe - never mind Einstein.

    No. The light expands in a sphere because in Einstein's universe the speed of light is the same in all directions in all inertial reference frames. There's no "pretend" about it.

    I didn't say I don't believe in space. I said I don't believe in your "space", by which I mean your fantasy absolute-zero-speed reference frame.

    See the difference?

    Because all the experimental evidence supports that conclusion.

    What have you got? Nothing.

    Very well. Give me enough information that I can work the problem. Either give me light travel times in a specified frame, or velocities of frames, or however you want to set it up. But if I have to keep asking you to make your scenario clear, I think I'll be far too bored to carry through with this additional pointless task.

    You have it wrong. Light will always take time L/c to travel along the ruler of length L, provided the length and time are both measured in the same reference frame.

    These repetitive exhortations to me to "get a grip on yourself" are becoming tiresome. You won't bully me into accepting your point of view. You'll need to provide some kind of evidence or argument, I'm afraid. I won't accept that you're right on the basis that your imagination is better than mine, or on the basis that you think I have an "illusion", but you can't prove it.

    Unless you have something better to offer than bluff and bluster about how relativity just can't be correct because you say it can't, you may as well stop at this point.

    There's no "pretend" about it.

    Do you agree that every object is at rest in its own reference frame? Yes or no?

    If you say "no", then you don't know what a reference frame is. Simple.

    Reference frames apply as much to the Motor Daddy universe as they do to Einstein's. In it's own frame, the cube in the Motor Daddy universe is at rest as surely as it is at rest in Einstein's universe. Otherwise, the term "reference frame of the cube" becomes meaningless.

    I also note that you have avoided addressing this point many times.

    Really? How fast is the Earth travelling in your absolute reference frame?

    Tell me. It's obviously important knowledge that everybody needs to know so that we can recalibrate all our rulers correctly. We can write to NIST to change the standards once we have your answer.

    Fine, so in the MD universe they are simultaneous in every frame. Not so in Einstein's universe.

    Yes.

    No. In Einstein's universe the strikes really do occur at different times in any other frame. That follows directly from Einstein's postulates. It's an unavoidable conclusion that doesn't depend on how smart anybody is.

    If you want to discuss yet another scenario with acceleration of some kind, you'll need to give me enough information to know what you're talking about, again. Generally I find it takes days to get from your initial description of a vague scenario to something that is firm enough that we can start calculating numbers. Then, usually half way through, you change the scenario or add extra features or whatever. And you're never truly interested in the analysis from Einstein's point of view anyway, so it's mostly a complete waste of time.

    To tell you the truth, I don't think you're capable of doing the maths for special relativity. You've never once demonstrated that you can solve even the simplest problem in Einstein's relativity. In fact, I challenge you to solve a simple problem using Einstein's relativity. Will you take me up on this, just so I know you know what you're talking about?

    If I'm going to tackle your two new scenarios using bothg Einstein and MD universes, the the least you can do is to solve one short problem using Einstein. Agreed?

    You realise that the train clocks and embankment clocks will lose synchronisation during the acceleration, do you not?

    There's nothing to defend, because no substantive attacks have been made.

    Einstein's "BS" is as secure as it has ever been. No uneducated Motor Daddy is going to upset that apple cart after 100 years of qualified physicists doing their darndest, I can assure you.

    Why do you keep talking about the "real world"? All you have is the fantasy Motor Daddy world, which has no connection to any "real world".

    Please drop this nonsense about the "real world". You wouldn't know the real world if it hit you in the face.

    When wheels rotate, the circumference changes due to length contraction.

    Gear ratios remain the same in different frames. RPMs do not, due to time dilation.

    Work and time and power are all relative - different in different reference frames.

    Yes. True in every frame.

    In which frame is the dyno?
     
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  5. AlexG Like nailing Jello to a tree Valued Senior Member

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    MotorDaddy's basic premise is that there is an absolute frame of reference.

    If you can't accept that, you don't belong in MD's non-reality.
     
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  7. Motor Daddy Valued Senior Member

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    I posted this in another thread, but I thought it was appropriate for this thread too, because it is in fact impossible to violate causality by traveling faster than the speed of light. As a matter of fact, if you could travel a hundred billion times faster than the speed of light you could not violate causality.

     
  8. quantum_wave Contemplating the "as yet" unknown Valued Senior Member

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    I saw that on the other thread and thought it was well said. Did you write it?

    It does apply to this topic but does not in anyway refute the soundness of the math of SR. Light itself always travels at c and you are basing your postulate on that fact. Would you address if your postulate agrees with the first postulate of SR:

    1. First postulate (principle of relativity)
    The laws by which the states of physical systems undergo change are not affected, whether these changes of state be referred to the one or the other of two systems of coordinates in uniform translatory motion.

    In other words the laws of physics work the same from all perspectives of motion, i.e. in all inertial frames of reference.
     
  9. Motor Daddy Valued Senior Member

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    Yes, I wrote it.

    "Undergo change" compared to what?
     
  10. quantum_wave Contemplating the "as yet" unknown Valued Senior Member

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    6,677
    Well said.
    Under go change follows from the laws that can affect objects. In this context I consider that to refer to changes in motion which translates to a change in perspective, also referred to as a change in frame of reference.
     
  11. Motor Daddy Valued Senior Member

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    5,425
    Thanks. My point is that no matter how fast you travel you can't break causality. It is impossible to go back in time because the clock keeps ticking no matter how fast you travel. The person traveling in that example started his journey in the year 2011 where he was. It was also the year 2011 on the star, as the light was originally emitted in the year 1911, and arrived at his position in the year 2011. So the light traveled for 100 years at the rate of c, which means the distance the light traveled was 100 light years, and it was the year 2011 on the star when the light arrived at the travelers start position. So it was 2011 at both positions (perfectly synchronized clocks) when the traveler started his journey. NO MATTER HOW FAST THE TRAVELER TRAVELED, HE COULD NOT GET TO THE STAR IN ZERO TIME OR LESS, AS IT TAKES TIME TO TRAVEL!

    Einstein's sync method is bogus!
     
  12. arfa brane call me arf Valued Senior Member

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    7,832
    But we use it with the GPS system. The GPS system is bogus (??)

    Actually, it's bogus for a moron who doesn't understand what a rest frame is, or what "at rest" really means, to say that Einstein's method is bogus.

    You are a moron. Therefore your claim is bogus. It doesn't even make sense.
    How does the fact it takes time to travel mean synchronisation is bogus? That's ridiculous. You are ridiculous.

    You keep coming out with totally incongruent objections, that only demonstrate your misunderstanding of Einstein's theory. Yet you keep claiming he's wrong; you don't even know what he was wrong about so you just make shit up.

    You're a total fuckwit.

    Yuh huh.
     
  13. quantum_wave Contemplating the "as yet" unknown Valued Senior Member

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    6,677
    Pretty interesting.

    http://public.web.cern.ch/public/en/LHC/CMS-en.html

    I guess you are a professional undeclared cult member. Or is that a professional undeclared non-cult member, lol.
     
  14. Neddy Bate Valued Senior Member

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    2,548
    I know you don't believe in it, but Relativity predicts there could be a violation of causality if information is sent faster than the speed of light.
    Consider the following diagram:

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    Let's say that at time 3.732 an instantaneous transmission of information is sent from the back of the train to the front of the train.
    As you can see in the diagram, the train clock at the rear of the train says time 2.732 and train clock at the front of the train says time 1.000.

    What would this look like in the train's own frame?
    At the time the signal was received at the front of the train, it would look like the third frame in this diagram:

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    So the information would be being received at a time when all clocks in the train say time 1.000.
    Yet, the signal would not be sent until time 2.732, which is a full 1.732 seconds later.
    Thus, the signal would be received before it was sent.
    Hence, this type of information transfer represents a violation of causality.
     
  15. arfa brane call me arf Valued Senior Member

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    7,832
    You could be making the mistaken assumption that MD understands what causality is.
    Or that he's prepared to consider any information that doesn't fit his moron model.
     
  16. Motor Daddy Valued Senior Member

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    5,425
    That's just an indication that Einstein's SR and his clock sync method is wrong, that is not a reality!

    It is impossible for travel to occur instantaneously.

    Again, Einstein's faulty clock sync method causes this problem.


    Address my scenario that I showed traveling at 2c to a star 100 light years away, and then we can talk. It is only possible in Einstein's world to cause a violation of causality due to his inaccurate methods. In reality, if you could travel 100 million times faster than the speed of light, you could NOT cause a causality violation. You can not go back in time!

    Einstein's methods cause all kinds of paradoxical illusions due to his faulty ways.

    My method has none of that garbage because it is correct.
     
  17. Neddy Bate Valued Senior Member

    Messages:
    2,548

    Good point, I might as well spell out what causality is, just in case. The "sending" of the information was the primary cause of the "receiving" of the information. If the information is received before it is sent, then the information is being received without any primary cause. Or, looking at it another way: If the information is received at time 1.000 but it is will not be sent until later at time 2.732 then it would be possible for the sender to decide not to send the information at all, even though it had already been received.

    Are you getting all this, MD?


    I know that he is very, very, resistant to considering anything that doesn't fit his model. In the occasional rare case where he does consider such a thing, he soon abandons that line of thought, and returns to his bold claims. It does not seem to bother him when his claims do not match reality, because he just rejects the reality. I don't know how he does it.
     
  18. Motor Daddy Valued Senior Member

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    Again, if you want to talk, address my scenario.

    Should I make it 100 times the speed of light and see what happens???

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  19. Neddy Bate Valued Senior Member

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    But his method can explain why light takes exactly 1/299,792,458 second to travel the length of a 90% platinum metre stick on earth. Your method cannot explain this at all.


    I used an instantaneous travel time in my example, but I didn't have to. Look at my diagram. The clock at the rear of the train says time 2.732 and the clock at the front of the train says time 1.000. So let the information require .001 seconds to travel the length of the train. The information is sent at time 2.732 and received at time 1.001. The information still has to arrive before it was sent, according to the train frame.


    You can't blame it on the synch method. Einstein would get the same results if he used YOUR synch method. If the two clocks on the train are started by pulling strings, they will both start simultaneously in the train frame. (Notice that the train-clocks are all synchronized to each other, according to my Train Frame diagrams.) But in the embankment frame, the two strings do not start the clocks at the same time, because of the relativity of simultaneity. Another thing you don't believe in.


    What's the point? If I address it by telling you how relativity works, you'll just say relativity is wrong. If I address it by using your method, I'd probably just agree with you.


    But it cannot be correct if it cannot explain why light takes exactly 1/299,792,458 second to travel the length of a 90% platinum meter stick on earth.
     
  20. Motor Daddy Valued Senior Member

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    5,425
    Tell you what. I'll give you a stick of unknown length and you tell me how much time it takes for light to travel each way along the stick. Stop trying to BS everyone. Light takes more or less time to travel the length of a meter in motion. The meter was in motion on the earth, so please, save the BS.





    The problem you represent is a problem created by Einstein's methods. If his methods were correct, like mine are, there would be no paradoxical BS!




    You understand my method, run the numbers using my method and see if there is a problem. Ned, just admit it's Einstein's incorrect method that causes the problem. It is not a reality.




    Right. My method doesn't stumble and start talking crazy talk at the speed of light, it just resumes as peaceful as can be, at any speed!




    BS! Measure the time of light travel of an unknown length of stick and get back to me.
     
  21. Neddy Bate Valued Senior Member

    Messages:
    2,548
    The 90% platinum metre stick was not in motion relative to the reference frame in which it was measured. So the light travel time is the same in both directions, just like my Train Frame diagrams show.

    If the 90% platinum metre stick had been moving when they tried to measure it, the light travel times would not be the same in both directions, just like my Embankment Frame diagrams show.


    Your method is compatible with certain parts of my diagrams. The red times in the Embankment Frame diagrams match your calculations. Why don't you go back and take a look at them?
     
  22. James R Just this guy, you know? Staff Member

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    Assuming we're working in Einstein's universe, that is incorrect. In Einstein's universe, it is possible for event A to occur before B in one frame, yet B occur before A in some other frame. Importantly, though, if A causes B then A must happen before B in every reference frame.

    If we could send information faster than the speed of light, then it would be possible to set up a situation in which the time order of two events was reversed in two different frames yet STILL have A causing B. Then, in the other frame we'd have A causing B even though A happened after B, which is a breach of causality.

    Your spaceship travelling towards a star example is not complex enough to create the kind of causality violation we need, so it is largely irrelevant and certainly proves nothing.

    Which sync method? And why?

    Again with your claims about "reality". Please give it a rest. You've never connected anything you've said with reality.

    What? Another one?

    I think it's time you did some work of your own, don't you? I note you haven't replied to my challenge to you to show me you can solve a problem in Einstein's universe. Is that because you can't do it?

    Like what?

    Another empty claim from you. *yawn*
     
  23. Motor Daddy Valued Senior Member

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    I don't live in Einstein's world, I live in mine. My world doesn't have paradoxical nonsense. You admitting that Einstein's world has causality violations is admitting to an error in his method, as in the real world, it is impossible to violate causality.


    His sync method is not of an absolute sync where the two clocks read as one. That causes the problems.

    Pay attention, James, I am talking about the scenario with the traveler traveling to the star at the rate of 2c.

    I asked you repeatedly to respond to my acceleration diagram or create one to show me you can use SR and acceleration like you claimed you could.

    You never gave me numbers in SR of my train and embankment scenario in which both were in motion. You are simply dodging the questions and then pretending I owe you something. Answer the questions before I respond to yours, James. You are boring me with your one line responses which lack substance.

    Like causing causality violations by traveling faster than light, for example.

    My method doesn't have problems at speeds above c.

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