Graphical Derivation of the CADO Equation

Discussion in 'Physics & Math' started by Mike_Fontenot, Sep 5, 2018.

  1. phyti Registered Senior Member

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    732
    You two seem to be enjoying this!
    May the farce be with you.
     
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  3. Neddy Bate Valued Senior Member

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    Right, time does not go backwards on anyone's own worldline. Back when you were claiming it would be a violation of causality for Charlie to calculate Alice's clock ticking backwards, I tried to reassure you that time would not be going backwards for Alice in her own frame. That was what I was trying to point out.

    I do vaguely remember some post where you said that t=40 coming before t=10 does not represent time going backwards. You do realize that 40 is greater than 10, right?

    No, but it has two different planes of simultaneity (grey dashed lines). There is a horizontal one for the ground frame, and a diagonal one for the train frame. When Charlie touches down on the ground, he uses the horizontal one and knows the time in the ground frame at x=0 is t=40. When he jumps back on the train, uses the diagonal and knows time in the ground frame at x=0 is t=10.

    I am purposefully using the word "knows" here, because I am also purposefully talking about the "time in the ground frame at x=0". No bomb can change time itself, and I wanted you to see that all your nit picking about bombs was for nothing. You're welcome!

    I'm glad you are "okay" with it, but how about addressing the concept that 40 is greater than 10. Doesn't that mean something in regards to the whole forwards vs. backwards thing? Hmm?

    Not only large accelerations, small ones too. Remember, the distance is also important. You might recall an alien named Bikey who only had to push his bicycle to make his "now slice" shift 200 years to the past on earth.

    Oh wait, I forgot, you think Bikey's bike has a huge acceleration. And you also think 200 years to the past is not backwards. Never mind, carry on!

    Talk about intellectual dishonesty. Time does not go backward on anyone's world line. To see the time going from t=40 to t=10, simply look at the two different intersections of the two different planes of simultaneity with the t axis. But according to you, time going from t=40 to t=10 is not backwards anyway, so don't worry about it.
     
    Last edited: Sep 27, 2018
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  5. NotEinstein Valued Senior Member

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    If you're not interested in an actual discussion on the topic, then why did you respond in the first place?
     
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  7. NotEinstein Valued Senior Member

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    Please point me to the post where I said that the result of the calculation in itself constitutes a violation of causality. Also, please stop it with the preferred frame again...

    Please point me to that post.

    You do realize it's disingenuous of you to make that statement? But then again, throughout this thread intellectual honesty hasn't proven your strong point.

    I'm glad you have finally hotten the point of the bombs. I'm glad I could help you grow intellectually.
    Actually, it wasn't. You're corrected a mistake in your language. That it took you so long isn't on me, though.

    How about showing some intellectual honesty, instead of continually misrepresenting my position?

    How about you demonstrate that the change from 40 to 10 is physically meaningful? You know, that kinda critical point you've been dodging for many posts now? Remember, even though Charlie calculates this, he never sees this. How do you resolve this conflict?

    How about you show some intellectual honesty and stop misrepresenting what I said?

    Indeed! This very paragraph of yours in an excellent example of intellectual dishonesty.

    But let me respond to the only bit that's the least intellectually dishonest, lest I be accused of ignoring something relevant.
    As I've said multiple times before: please demonstrate that this effect (re-ordering events in the space-like region) is physically meaningful.
     
  8. Neddy Bate Valued Senior Member

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    2,548
    Post #38:
    "I think you've just violated causality. " -NotEinstein

    You wrote that in response to a post I made where Charlie calculated Alice's age to go back to 10 after he previously calculated it to be 40.

    I gave you a Minkowski diagram showing that Charlie calculates Alice's time to go from t=40 to t=10. You pointed out that time on Alice's own worldline does not go backward. So when you do it, it's okay. But when I do it, you accuse me of believing in a preferred frame.

    Okay, how about this instead, the time going from t=40 to t=10 does not happen in any single inertial frame. Better? I'm sure I've already stated that in this thread.

    It is t=40, x=0 when Charlie touches down in the ground frame, and t=10, x=0 when Charlie jumps back on the train. Obviously that is not from one single inertial frame, but two frames minimum.

    Oh sorry, maybe you never actually said that t=40 coming before t=10 was not time going backward. So you agree that t=40 coming before t=10 is time going backward then?

    If you answer "no" in your next post, then the post you are asking me to point to is your next post. But of course you will not answer with a yes or no, so that won't happen.

    So the whole point of the bombs was just to get me to call it "time" instead of "the time displayed on Alice's clock?" Why didn't you just tell me that you refuse to use common conventions of SR thought experiments, and that you would prefer not to use any clocks at all, because of bombs and such? I would have understood (that you were, um, 'eccentric').

    I already answered that, and you said it wasn't even an answer. You can look up my previous answer if you want to, because I'm not going to repeat it after that reply.

    I don't think there are any inherent 'conflicts' in SR. But since you do, maybe you should write a paper on it, and get it peer reviewed. You could be the next Nobel winner.

    I already answered that, and you said it wasn't even an answer. You can look up my previous answer if you want to, because I'm not going to repeat it after that reply.

    So, we still have time t=40, x=0 coming before time t=10, x=0 (as Charlie jumps from the ground onto the train). And you still have not accepted that is time going backwards. And you say that it is not meaningful. And you say that there is a conflict between that and what Charlie sees. So I think we are done here. You just don't accept SR, that's all.
     
  9. NotEinstein Valued Senior Member

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    1,986
    Ah, so a post from before the distinction between calculations, measurements, and observations, so that's not a proper reflection of my position for the past several pages. Also note the "I think".

    I'll be more clear:
    Please point me to a relevant post where I said that the result of the calculation in itself constitutes a violation of causality.

    And my statement is correct: Alice does not. Follow her worldline; does it go from 40 to 10 at any point? No.

    My point is that there's a seeming discrepancy between what's happening in reality (the worldlines in the Minkowski diagram) and the result of Charlie's calculations. A discrepancy that I've solved, but you apparently haven't (yet?). My statement makes clear that you still have a problem to solve; it's staring you right in the face, but you refuse to acknowledge it.

    So me pointing out the sheer silliness of your "preferred frame" nonsense is now a bad thing?

    So the jump backwards in time is an effect experienced by a remote observer caused purely due to that observer switching inertial frame, and not due to time ticking backwards where Alice is? I can live with that, yes. It's what I've been getting at for the last several pages. I'm glad you're following along!

    Yes, obviously.

    Yes, of course I do; it's pretty much the definition, isn't it? I mean, that's what kicked off this entire discussion.

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    I answered "yes", because that's the position I obviously always held. So where's that post then?

    A fine case where you are demonstrably wrong.

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    That's what you turned it into, which works too. I was aiming more at the fact that you were calling what Charlie calculated as what happened in reality, mainly when we were still talking about Alice getting onto the train. You muddied that by switching scenario's (which you do a lot mid-conversation).

    Actually, if you actually studied SR more carefully, you wouldn't have gotten confused by this at all. But nuance seems to be a thing strange to you.

    I don't mind using clocks at all. Take the recent example of the opposite site of the earth. Did the bomb destroy the clock? No. So why are you still going on about the confusion you created for yourself after we cleared that up?

    I'd rather be "eccentric" than have the level of intellectual dishonesty you've displayed in this thread, thank you very much.

    So, you're not going to address it then, as you before. How very reasonable of you.

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    I agree, so there must be a resolution to it. But can you find it? I've only mentioned it multiple times in this thread so far; I'm not sure that was enough times for you.

    And here we go with the intellectual dishonesty again.

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    Not going to happen, as I don't live in your fantasy world.

    So, you're not going to address it then, as you before. How very reasonable of you.

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    No we don't. Charlie's calculations have that. But no observer has that. Demonstrate that Charlie's calculations about the order of events actually plays out.

    Oh wait, you refuse to address anything related to "physical meaning".

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    And you still haven't read the article about the "arrow of time".

    Only about a dozen times now, yes.

    And you agree with that: you stated yourself that Charlie never sees Alice going backwards in time.

    Aw come on, you're so close to actually understanding what's going on!

    Actually, I fully except SR. I'm just more aware of its nuances.

    ---

    This has been quite fascinating so far. I've never engaged with somebody like you before. You show all the signs of a pseudoscience-peddler (intellectual dishonesty, misrepresentations, lack of detailed knowledge on the subject, failure to address issues brought up, selective quoting, etc.), but you're not actually peddling pseudoscience: you're just peddling an unnuanced view of SR. Very interesting. Thank you for this experience!

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  10. Neddy Bate Valued Senior Member

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    2,548
    Okay, so I think we can agree that the results of Charlie's calculations do not constitute a violation of causality in and of themselves. Please correct me if I am wrong on that.

    Now, what about if Charlie takes the result of his calculation from when he is on the ground, and concludes that the current time at x=0 must be t=40 at that moment in reality, and what about if Charlie subsequently takes the result of his calculation from when he jumps back on the train, and concludes that the current time at x=0 must be t=10 at that moment in reality? Do those two conclusions, taken together, violate causality, in your opinion?

    In that case, you should accuse yourself of invoking a preferred frame. At least try be consistent. You accuse me of invoking a preferred frame every time I say that time does not go from 40 to 10 in Alice's own frame.

    Well your statement is no different than my statement.

    "Follow her worldline; does it go from 40 to 10 at any point? No." = NotEinstein has solved an apparent discrepancy (according to NotEinstein).

    "Time does not go from 40 to 10 in Alice's own frame." = Neddy Bate is invoking a preferred frame (according to NotEinstein).

    At least try to be consistent.

    Yes, and it has always been a bad thing, because it is false. I don't claim a preferred frame any more than you do. The difference is that I don't falsely accuse you of it.

    That is what I have been saying, too. But again, you give only yourself credit for it.

    Okay, so when Charlie calculates that t=40 comes before t=10, he is calculating something which meets your definition of "time going backwards," right?

    Now, what about if Charlie takes the result of his calculation from when he is on the ground, and concludes that the current time at x=0 must be t=40 at that moment in reality, and what about if Charlie subsequently takes the result of his calculation from when he jumps back on the train, and concludes that the current time at x=0 must be t=10 at that moment in reality? Is he concluding something which meets your definition of "time going backwards"?

    I am not confused by any of this. You were the one who thought that you could demonstrate a contradiction in SR by putting a pressure pad under Alice, not realizing that t=10, x=0 and t=40, x=0 are different events. You are also the one who claimed GR would be required to 'supersede' the results of SR. And so on.

    What? Please tell me you have a typo in there or something.

    That posting seems to have the exact opposite meaning from what you were actually saying in that recent example. You were the one saying that I could not know the time on the opposite side of the earth right now, because all the clocks might have been blown up by a bomb. But of course time itself cannot be blown up.

    I can know the time on the opposite side of the earth because we have a convention of time zones on earth. Likewise, Charlie can know the time at x=0 because SR has its own convention. Charlie knows without any doubt that t=40, x=0 changed to t=10, x=0 between the time he was on the ground, and when he jumped on the train. That is what SR says.

    Maybe its that time never goes backward on Alice's worldline? Maybe its that no one ever sees Alice's clock run backward? Who knows? But of course, you only give yourself credit for it, whatever it is.

    I tried, with the DVR's, but you rejected it. Charlie has two videos, one showing t=40 x=0 at the moment he was on the ground, and the other showing t=10 x=0 at the moment after he jumped on the train.

    He doesn't see it with his eyes, no. But he knows he was on the ground before he jumped back on the train. And he knows he set his two DVRs correctly, based on the distances involved. That's all he has to go by, physically, and it matches the SR calculations. What else is there? Please do tell.
     
  11. NotEinstein Valued Senior Member

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    1,986
    Of course. Writing t=40 before t=10 on a piece of paper doesn't violate causality, and I never claimed otherwise.

    No, because his second conclusion "overwrites" his first. Charlie will conclude t=40 at two moments; the first time gets invalidated during his jump back on the train. It's easy to see: we agree there's only one coordinate (x=0, t=40). After his switch of inertial frame, when information (light) of the (x=0, t=40) event finally reaches Charlie, which of this two conclusions turns out to be correct? The second one. His first conclusion never pans out (in any physically meaningful way).

    Erm, my entire point is that you should be consistent. Why is it OK for you to work in preferred frames, but not for me?

    Please point me to a post where I did that.
    At least you're consistent with the intellectual dishonesty.

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    And I see you once again dodge the question asked of you. As I just said, at least you're consistent!

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    You don't explicitly claim, no, but you do use it. Go back to when I asked you about the violation of causality: you'll notice that you were abandoning Charlie's point of view for Alice's quite a lot. You preferred Alice's frame. I pointed that out multiple times to you.

    But I'm glad you now agree that it's a bad thing, and that all your argument bad then doing that were thus bad. Glad we cleared that up, and I'm glad I could help you grow intellectually!

    Incorrect; the accusation isn't false. Thus I'm also not falsely accusing you of it.

    Notice how I'm using the word "effect", and I'm explicitly putting its experience by the remote user. This crucially means no traveling backwards in time happens; there are no clicks ticking backwards. That's what I've been saying all along.

    I give myself credit for the nuance which resolves the conflict I pointed out. You can't honestly claim credit for that, because you can't even see the conflict!

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    If this calculation bears out in reality. Charlie could also be smart, know a little bit about SR, and realize his switching of inertial frame invalidates the results of his first calculation.

    Oh, and I find it funny that you completely ignore that you were wrong with your entire silly "But of course you will not answer with a yes or no, so that won't happen.". See, that's what happens when you put words in other people's mouths: you might be incorrect, and look a bit silly.

    I invite you to demonstrate that the results of Charlie's first calculation still hold after his switch of inertial frame. I'm pretty sure you'll find that even Charlie disagrees with you.

    Yes. He's quite literally claiming there's a place in the universe where time went from t=40 to t=10, which is time going backwards.

    Luckily for us, reality doesn't conform to misinterpretations of calculations.

    Read back this entire thread. There's various points in it where I point out your confusion.

    False; I never claimed that. More intellectual dishonesty from you.

    False; I've always claimed that. More intellectual dishonesty from you.

    And it does. More intellectual dishonesty from you.

    Yes, this entire thread is turning into more intellectual dishonesty from you.

    Typo? I don't see any?

    Sure; because you are constantly misinterpreting my posts, it might seem that way to you. In reality, it's perfectly consistent with it.

    Right, because it's invalid to talk about "the time on the opposite side of the earth right now" if there is no "the opposite side of the earth right now".

    False; that's your misrepresentation about my argument.

    True; and I never claimed otherwise. More intellectual dishonesty from you.

    No, you don't know. You can conclude what it would be, assuming the opposite side of the earth still exists as you expect it to.

    It's fascinating to see you continually get and then un-get the point.

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    Sure, but as soon as Charlie makes statement like "Alice's jumps onto the train" without information about it having been able to reach him, he's wrong (or rather: making assumptions).

    Yep. I fully agree. But it's not that time ticked backwards; it's that his second calculation invalidates his first.

    And I never claimed otherwise.
     
  12. NotEinstein Valued Senior Member

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    1,986
    There, right there! Do you see it? We were talking about Charlie, and you sneakily switch to Alice. There's your preferred frame for you!

    So now you're arguing Charlie's calculations are incorrect? I thought we agreed they weren't?

    Clearly, you don't, and you seems to struggle to even understand the conflict. But as we've seen progress from you along the way (and several relapses), you might be able to reach a resolution! Just keep on trying; you'll get there!

    Well, I can give you credit for "forcing" me to think this through, certainly. But I can't give you credit for the resolution, because you didn't (directly) help with that at all. Heck, you don't even accept there is a conflict!

    No, I didn't. I just pointed out that the DVR's as observers also don't see any backwards-in-time stuff, and that it only proves Charlie's calculations aren't incorrect. It's not evidence of backwards-in-time ticking clocks, because that's quite literally not on tape!

    And now use your Minkowski diagram: what conclusions about the first DVR's starting moment of recording does Charlie draw?

    "That's all he has to go by, physically"? You quite literally three sentences before said: "He doesn't see it with his eyes, no.". Direct observation doesn't count as physically relevant?

    Oh boy, would I like to see your definition of physical relevance!

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    Nothing else. You have two pieces of information: the results from Charlie's calculations, and the results from Charlie's observations. One says Alice's clock tick backwards, the other doesn't. I guess outright rejecting direct observational evidence is also a way to resolve the conflict. That actually matches the pseudoscience-peddling profile quite nicely.

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  13. phyti Registered Senior Member

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    732
    Have encountered the CADO equation before and know it's an idea based on a sloppy interpretation of the twin scenario. It's interesting to see if people buy into the idea.
     
  14. NotEinstein Valued Senior Member

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    1,986
    Ooh, interesting! Can you give more details?

    Well, I haven't bought into it (yet?), because I haven't checked the details. I did encounter sloppy and lacking definitions, but Mike said he'd fix those.
     
  15. Neddy Bate Valued Senior Member

    Messages:
    2,548
    Thank you, at least this is a some type of explanation. All this time I have been trying to understand how you could think that time at x=0 going from t=40 to t=10 would not be time going backwards. But if the t=10 "overwrites" the t=40 then we can safely leave out the word "backwards" and just deal with the results. I'm tempted to just agree with you and leave it at that, but unfortunately, there is one small aspect of this explanation that bothers me. From further down in your post:

    Of course the first result t=40, x=0 would not hold true from the train frame, which is where Charlie is after he jumps on the train. The train frame is where the second result t=10, x=0 holds true.

    However, the first result t=40, x=0 does still hold true from the ground frame, even after Charlie jumps back on the train. That is what Charlie demonstrated when he set the ground-DVR to record with a 34.64 year delay, and obtained the broadcast from t=40, x=0.

    That happened after Charlie jumped on the train. So your 'overwrite' idea is nice, from Charlie's point of view, but you can't just make the first result go away altogether.

    But you don't believe time goes backwards, so you must not agree with one or the other part of this:

    1. Now, what about if Charlie takes the result of his calculation from when he is on the ground, and concludes that the current time at x=0 must be t=40 at that moment in reality,

    2. and what about if Charlie subsequently takes the result of his calculation from when he jumps back on the train, and concludes that the current time at x=0 must be t=10 at that moment in reality?

    Can't you just waive your magic wand and say that the second result overwrites the first? Or are we back to square one, with time going backwards again?

    PS:
    I apologize for not addressing every part of all of your posts. I feel like there have been way too many side issues, and our posts have been getting much longer than they need to be. I think that the only issues that we really need to address now are covered in this post.
     
    Last edited: Sep 28, 2018
  16. NotEinstein Valued Senior Member

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    1,986
    And more misrepresentations.

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    Well, good thing I never claimed that. In fact, I claimed the very opposite! But you'd know that, if you cared to remember.

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    Show me any evidence (measurements, observations) that it ever did. I'm talking actual, empirical data.

    I'll wait.

    (I see that this is a copy-paste from your post #207.)

    No, because I don't have any. Do you?

    Read post #208 again. If you ask the same question, you'll get the same answer.

    I always objected to time going backwards, remember? So perhaps you're back to square one, not me.

    I see you've once again skipped over the preferred frame stuff...

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    ---

    Very interesting behavior. This time you got close to understanding, but then through repeating you own old stuff back at yourself, you managed to veer off-course and went back the way you came. And then you of course projected that failure onto me. It seems you'll do anything (subconsciously?) to avoid resolving the conflict, or admitting the failure to do so is on you.
     
  17. Neddy Bate Valued Senior Member

    Messages:
    2,548
    Huh? Sorry, I don't understand.

    Charlie's first calculation still holds true (in the ground frame) even after Charlie switches back to the train frame.

    So all I want to know is how you can claim that his second calculation "overwrites" his first calculation?

    That is the only thing holding me back from agreeing with your "overwrites" idea.
     
  18. phyti Registered Senior Member

    Messages:
    732
    If two clocks separate and reunite, is there a difference in accumulated time for the clocks?

    Making use of the three clock 'twin' scenario, fig.1 shows the physical setup that corresponds to fig.2 a graphical representation of ct vs x.

    A sends a (blue) narrow beam of light after B leaves A at .6c Emission occurs at A2, and reaches B at A5. C is moving at .6c toward A in the opposite direction and receives the same clock image at A5. As C passes B, the C-clock is set to the B4 clock time. The C inbound trip is the mirror image of the outbound trip. This scenario avoids accelerated motion and the fictitious 'time jump. Applying time dilation to each segment of the closed course results in the B+C history accumulates less time than the A history.

    The clock synch convention with its axis of simultaneity, distorts the time coordinates of events.

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  19. Mike_Fontenot Registered Senior Member

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    In the three "twin" scenario (with each "twin" being perpetually inertial), none of the "twins" are surprised about the outcome of the scenario, so there is no apparent paradox to resolve. The original scenario does produce an apparent paradox (when the unwarranted assumption is made that nothing of interest about the two twins' ages can possibly happen in a single instant). That apparent paradox can be resolved only by learning that the instantaneous turnaround of the traveling twin causes the home twin's age to instantaneously increase (according to the traveler) by just the amount needed to eliminate any surprise at the reunion.
     
  20. bharaja Registered Member

    Messages:
    25
    nobel prize.
     
  21. phyti Registered Senior Member

    Messages:
    732
    No one is expecting a surprise.
    The discontinuous speed profile at reversal is the problem. The clock synch convention is based on continuous inertial motion, and that does not exist at reversal.
    Why develop a theory to correct a mistake?
     
  22. Neddy Bate Valued Senior Member

    Messages:
    2,548
    Just replace the discontinuous speed profile (v to -v in zero time) with a continuous speed profile (v to -v in an arbitrarily small amount of time). Now the speed profile is continuous.

    For consistency, we must assume that after the reversal (turn-around), when the speed is once again constant (inertial motion), that the clock synch convention has been re-applied. Otherwise we would be left with multiple clock synch conventions.

    SR was not a developed to correct a mistake, if that is what you mean.
     
  23. phyti Registered Senior Member

    Messages:
    732
    No one said that. The subject is the CADO concept. What's missing is a continuous curve connecting the outbound and inbound profiles.
    That would require a single wandering twin to continuously re-synch the clocks for the duration of the reversal.
    The jump is a fictitious, man-made problem resulting from a poorly formed pictorial representation.
    Correct the graphics and the missing time issue disappears!
     

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