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Thread: Is Einstein correct?

  1. #1 Is Einstein correct? 
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    Is Einstein correct about relativity?


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    Time Lord Paleoichneum's Avatar
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    in what way?


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    Quote Originally Posted by Paleoichneum View Post
    in what way?
    .

    In a simultaneity way?

    Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion.
    The above sentence does not seem accurate .
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    Quote Originally Posted by coldshoulder View Post
    Quote Originally Posted by Paleoichneum View Post
    in what way?
    .

    In a simultaneity way?

    Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion.
    The above sentence does not seem accurate .
    The statement, which expresses what is known as the "Relativity of Simultaneity", is in fact, correct.

    It is probably the most difficult concept people have to come to terms with when introduced to Relativity. It seems like common sense that events that are simultaneous for one person would be automatically simultaneous for any other person. But this common sense conclusion is based on the fact that the velocities we are used to dealing with in everyday life are actually very slow, and while the Relativity of Simultaneity does apply at these speeds, it would be very, very hard to measure it. We assume that the same events are simultaneous for everyone just because the small difference is too small to notice. It is like the fact that the world is round, but if measured over very short distances, it seems to be flat. Once you start measuring larger and larger distances, the curvature becomes noticeable. In the same way, simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case.
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    I've had conversations with people about this and wound up being ignored.
    Some people are so staunch in their religious beliefs they won't accept the science.
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    Quote Originally Posted by coldshoulder View Post
    Is Einstein correct about relativity?
    He is correct about relativity, in the sense that to date all predictions made by the model match very well with experiment and observation in the real world.

    Relativity is fundamentally a model of space and time; so far as Special Relativity in particular is concerned, the basic idea is that all inertial observers experience the exact same laws of physics, regardless of their position or state of relative motion. That essentially means that we would expect the electronic equipment here in our labs, and the equipment on board (e.g.) the spacecraft Voyager, to work in the exact same manner, because both are subject to the same laws. Mathematically that is so because the metric of spacetime is invariant - when you go from one inertial reference frame to another, then that transformation leaves the metric - and hence all laws of physics - unaffected.

    When you investigate this and think it through to the end, all manner of seemingly strange conclusions follow from this simple fact, not least of which is the relativity of simultaneity. However, this seems strange to us only because our everyday experience of the world is a Euclidean one, whereas in reality spacetime is not Euclidean; it's just that this becomes obvious only once reference frames are related in certain ways, e.g. when they are rotated about some angle, which physically means there is relative motion at high velocity. In our everyday lives, we don't consciously encounter such situations, even though some simple facts ( e.g. the colour of gold ) are direct results of relativity.

    Either way, to the best of our currently available data, the theory of relativity is a good and valid description of some aspects of the world around us.
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    Quote Originally Posted by Janus View Post
    Quote Originally Posted by coldshoulder View Post
    Quote Originally Posted by Paleoichneum View Post
    in what way?
    .

    In a simultaneity way?

    Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion.
    The above sentence does not seem accurate .
    The statement, which expresses what is known as the "Relativity of Simultaneity", is in fact, correct.

    It is probably the most difficult concept people have to come to terms with when introduced to Relativity. It seems like common sense that events that are simultaneous for one person would be automatically simultaneous for any other person. But this common sense conclusion is based on the fact that the velocities we are used to dealing with in everyday life are actually very slow, and while the Relativity of Simultaneity does apply at these speeds, it would be very, very hard to measure it. We assume that the same events are simultaneous for everyone just because the small difference is too small to notice. It is like the fact that the world is round, but if measured over very short distances, it seems to be flat. Once you start measuring larger and larger distances, the curvature becomes noticeable. In the same way, simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case.

    I do not think it is difficult to understand, I just do not think it is accurate. In my opinion, the relativity of simultaneity is sight based, the event being synchronous to all but observed at different times because of how sight works. The Sun, the Earth and Uranus all occupy the present at the same time, if the sun was to explode, it would explode in the present of the mentioned, but observers on Earth and Uranus would observe the event happen at different times because of how sight works.


    So I stick to my initial thought that the statement is not accurate or complete, unless anybody can add further more to simultaneity and convince me otherwise.
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    Genius Duck Moderator Dywyddyr's Avatar
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    Quote Originally Posted by coldshoulder View Post
    So I stick to my initial thought that the statement is not accurate or complete
    Without evidence what you think is just that: what YOU think. (And wrong).

    unless anybody can add further more to simultaneity and convince me otherwise.
    Actually learning physics might help you.
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    So I stick to my initial thought that the statement is not accurate or complete
    Without evidence what you think is just that: what YOU think. (And wrong).

    unless anybody can add further more to simultaneity and convince me otherwise.
    Actually learning physics might help you.
    An absence of evidence is not conclusive that somebody is wrong.
    They could be right but don't have the evidence.
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    So I stick to my initial thought that the statement is not accurate or complete
    Without evidence what you think is just that: what YOU think. (And wrong).

    unless anybody can add further more to simultaneity and convince me otherwise.
    Actually learning physics might help you.

    That seems a reply that is not really giving an answer. Are you saying how sight works is not providing evidence?

    Are you saying my example of the Sun, the Earth and Uranus is wrong?


    I am sorry but I know that is correct.
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    Genius Duck Moderator Dywyddyr's Avatar
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    Quote Originally Posted by coldshoulder View Post
    I do not think it is difficult to understand, I just do not think it is accurate.
    Then you are wrong.

    In my opinion, the relativity of simultaneity is sight based
    Also wrong.

    but observers on Earth and Uranus would observe the event happen at different times because of how sight works.
    It's nothing to do with "sight".

    Which part of "simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case" in Janus' reply did you not understand?

    Moved to Personal Theories.
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    I do not think it is difficult to understand, I just do not think it is accurate.
    Then you are wrong.

    In my opinion, the relativity of simultaneity is sight based
    Also wrong.

    but observers on Earth and Uranus would observe the event happen at different times because of how sight works.
    It's nothing to do with "sight".

    Which part of "simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case" in Janus' reply did you not understand?

    Moved to Personal Theories.
    How strange that you move a question about present information to new theories when there is no new theory involved. Quite clearly the moderator does not know how sight works and can not think about this for themselves.

    Where is the personal theory involved in this?
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  14. #13  
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    Quote Originally Posted by coldshoulder View Post
    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    I do not think it is difficult to understand, I just do not think it is accurate.
    Then you are wrong.

    In my opinion, the relativity of simultaneity is sight based
    Also wrong.

    but observers on Earth and Uranus would observe the event happen at different times because of how sight works.
    It's nothing to do with "sight".

    Which part of "simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case" in Janus' reply did you not understand?

    Moved to Personal Theories.
    How strange that you move a question about present information to new theories when there is no new theory involved. Quite clearly the moderator does not know how sight works and can not think about this for themselves.

    Where is the personal theory involved in this?
    I have a personal theory that you have brought nothing (yet) to the question "was Einstein wrong"
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    Genius Duck Moderator Dywyddyr's Avatar
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    Quote Originally Posted by coldshoulder View Post
    How strange that you move a question about present information to new theories when there is no new theory involved.
    Correct. There's no theory per se, yet the entire thread is predicated on your personal belief (which you have stated a number of times). Please note that the sub-forum is actually entitled Personal Theories and Alternative Ideas.
    Do you deny that what you're propounding is an "alternative idea"?

    Quite clearly the moderator does not know how sight works and can not think about this for themselves.
    Really?
    Or, perhaps you don't actually mean "sight" (i.e. the perception of objects by humans/ animals) but something else altogether.

    Where is the personal theory involved in this?
    The above sentence does not seem accurate - post #3.
    In my opinion, the relativity of simultaneity is sight based - post #7.
    I am sorry but I know that is correct - post #10.
    Etc.

    You aren't (despite the OP) asking to have the (verified) science explained to you but are, instead, disputing that: i.e. proposing that science is wrong and that [whatever idea you you have] is correct.
    The fact that it's not a theory (in a scientific sense) is due the complete lack of support from you.
    OTOH I could always move the thread to Trash.
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    Quote Originally Posted by geordief View Post
    Quote Originally Posted by coldshoulder View Post
    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    I do not think it is difficult to understand, I just do not think it is accurate.
    Then you are wrong.

    In my opinion, the relativity of simultaneity is sight based
    Also wrong.

    but observers on Earth and Uranus would observe the event happen at different times because of how sight works.
    It's nothing to do with "sight".

    Which part of "simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case" in Janus' reply did you not understand?

    Moved to Personal Theories.
    How strange that you move a question about present information to new theories when there is no new theory involved. Quite clearly the moderator does not know how sight works and can not think about this for themselves.

    Where is the personal theory involved in this?
    I have a personal theory that you have brought nothing (yet) to the question "was Einstein wrong"

    I have asked the question in an understandable manner, it is no more than a question, I don't understand why such hostile treatment to a new member. I do not think I will be participating in this forum very much.


    Do all planets exist in the present ?

    Does light take time to arrive at your eyes?

    If both answers are yes, then Simultaneity is not accurate.
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    Genius Duck Moderator Dywyddyr's Avatar
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    Quote Originally Posted by coldshoulder View Post
    I have asked the question in an understandable manner, it is no more than a question
    Already shown to be false with the quoted statements.
    You aren't just asking questions, you're claiming (despite the lack of evidence and against the tried and tested facts) that the current theory is wrong.

    I don't understand why such hostile treatment to a new member.
    Perhaps if you'd confined yourself to simply asking questions (per your false claim), as opposed to making unfounded claims, you'd have had a better reception.

    Do all planets exist in the present ?
    Their own present.

    Does light take time to arrive at your eyes?
    Yes.

    If both answers are yes, then Simultaneity is not accurate.
    See the answer to the first of those questions.
    And, for the record, claims like "Simultaneity is not accurate" when (again) the principle has been shown to be true, is NOT simply asking questions. Nor is (apparently) completely ignoring the answers (by Janus and Markus) the way to go about things.
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    I have asked the question in an understandable manner, it is no more than a question
    Already shown to be false with the quoted statements.
    You aren't just asking questions, you're claiming (despite the lack of evidence and against the tried and tested facts) that the current theory is wrong.

    I don't understand why such hostile treatment to a new member.
    Perhaps if you'd confined yourself to simply asking questions (per your false claim), as opposed to making unfounded claims, you'd have had a better reception.

    Do all planets exist in the present ?
    Their own present.

    Does light take time to arrive at your eyes?
    Yes.

    If both answers are yes, then Simultaneity is not accurate.
    See the answer to the first of those questions.
    And, for the record, claims like "Simultaneity is not accurate" when (again) the principle has been shown to be true, is NOT simply asking questions. Nor is (apparently) completely ignoring the answers (by Janus and Markus) the way to go about things.
    Ok, point taken although what I deem to be discussion , you do not deem to be discussion. What you are saying to me is that present science information is not negotiable or a person is not allowed to discuss it. I can understand why the other member mentioned religion if this is the case on this forum. However I will stick to your guidelines and let you answer it for yourselves by answering the questions.

    You say Yes , light takes time to arrive at your eyes.

    Then you must agree that two observers at different distances away from an event observe the event at different times?
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    Genius Duck Moderator Dywyddyr's Avatar
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    Quote Originally Posted by coldshoulder View Post
    Ok, point taken although what I deem to be discussion , you do not deem to be discussion.
    Except that you aren't discussing[1] - you have made specific claims.
    And ignored responses.

    What you are saying to me is that present science information is not negotiable or a person is not allowed to discuss it.
    No, what I'm saying is this: there is tried and tested evidence AND logical reasoning (& maths) based on known facts for Einstein's position.
    So far there is none whatsoever for yours (incredulity doesn't count as an argument).

    Then you must agree that two observers at different distances away from an event observe the event at different times?
    Correct.

    1 Although what happened to your earlier claim to be questioning I don't know...
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    Ok, point taken although what I deem to be discussion , you do not deem to be discussion.
    Except that you aren't discussing[1] - you have made specific claims.
    And ignored responses.

    What you are saying to me is that present science information is not negotiable or a person is not allowed to discuss it.
    No, what I'm saying is this: there is tried and tested evidence AND logical reasoning (& maths) based on known facts for Einstein's position.
    So far there is none whatsoever for yours (incredulity doesn't count as an argument).

    Then you must agree that two observers at different distances away from an event observe the event at different times?
    Correct.

    1 Although what happened to your earlier claim to be questioning I don't know...
    Firstly I have made no specific claims, I am quite sure the claims you think I am making are of your imagination and ambiguity of how you are reading my questions.


    As yet you have said correct /yes , twice.

    I wonder how many more yes/correct answers you will reply that shows the inaccuracy in simultaneity thinking.


    I will now revert back to my original quote:

    Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion.
    I will now refer to a geometrical position question.


    Observer (A) is an equal distance apart from the Sun as Observer (B) , the Sun is in the middle. For purposes of the question, the Observers rotate around the Sun and remain an equal distant apart retaining a linearity between them.


    The observers are both exactly 149.6 million km from the sun apart, r1=149.6 million km , r2=149.6 million km


    The time it takes for the light to reach observer 1 is 8 minutes and 24 seconds (approx), If the Sun was to explode it would take 8 minutes and 24 seconds for observer 1 to see this.


    Can you please answer , how long does it take for observer 2 to see the sun exploding?
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    Quote Originally Posted by coldshoulder View Post
    Firstly I have made no specific claims
    So it wasn't you who wrote I am sorry but I know that is correct or even the statement is not accurate or complete?

    I am quite sure the claims you think I am making are of your imagination and ambiguity of how you are reading my questions.
    Right.

    I wonder how many more yes/correct answers you will reply that shows the inaccuracy in simultaneity thinking.
    You still haven't explained why (you think) this is the case.

    I will now revert back to my original quote
    Don't bother.
    The part you persist in ignoring is here (and you quoted it):
    Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion.
    I will now refer to a geometrical position question.
    Geometry is not relative motion.
    One more time: Which part of "simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case" in Janus' reply did you not understand?
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    Firstly I have made no specific claims
    So it wasn't you who wrote I am sorry but I know that is correct or even the statement is not accurate or complete?



    I am quite sure the claims you think I am making are of your imagination and ambiguity of how you are reading my questions.
    Right.

    I wonder how many more yes/correct answers you will reply that shows the inaccuracy in simultaneity thinking.
    You still haven't explained why (you think) this is the case.

    I will now revert back to my original quote
    Don't bother.
    The part you persist in ignoring is here (and you quoted it):
    Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion.
    I will now refer to a geometrical position question.
    Geometry is not relative motion.
    One more time: Which part of "simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case" in Janus' reply did you not understand?

    I know I was correct about how sight works, not I was correct about the inaccuracy. I was asking about what I thought is an inaccuracy and wanted to discuss this using present information. i.e How sight works and the constant of light .

    I can also ''see'' you are not willing to discuss or reply with an answer to my question scenario. You know very well the scenario I just explained with relative motion shows simultaneous, so you choose to ignore the question and then reply back with present information which dOES not answer my question about the inaccuracy I deem.


    Which part of "simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case" in Janus' reply did you not understand?
    I have no idea how this relates to my question or is an answer to the inaccuracy or even what it means. Sounds Gibberish to be honest.
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    Genius Duck Moderator Dywyddyr's Avatar
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    Quote Originally Posted by coldshoulder View Post
    I can also ''see'' you are not willing to discuss or reply with an answer to my question scenario. You know very well the scenario I just explained with relative motion shows simultaneous, so you choose to ignore the question and then reply back with present information which DOES not answer my question about the inaccuracy I deem.
    No.
    You are looking at as - Janus noted - a case where the relative speeds are low: I.e. the theory is "inapplicable" in such cases (to be more accurate, the results - as given by Einstein - are so small as to be insignificant).


    I have no idea how this relates to my question or is an answer to the inaccuracy or even what it means. Sounds Gibberish to be honest.
    It's quite simple.
    A quick look at the relevant Wiki page (which you appear to have not even tried) states: simultaneity – whether two spatially separated events occur at the same time – is not absolute, but depends on the observer's reference frame.

    Note that part about reference frame.
    Where relative speeds are low (or non-existent) the all bodies are in the same frame.
    At high relative speeds the are in different frames and THAT is when the theory comes into play.
    You - while persisting with your "example" are arguing that Einstein is wrong (when in fact the results are exactly as predicted) by completely ignoring cases where the effects come into play.

    Mod comment:
    In point if fact if - truly - you don't don't know how this relates to your question then the obvious conclusion is that you don't actually know what Einstein said about the relativity of simultaneity: in other words you're arguing against something you don't understand and haven't looked at.
    Or, possibly, you're just trolling...
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    Maybe both.Can trolling (or disingenuity) be used to mask ignorance?
    Perhaps the answer is obvious.
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    I can also ''see'' you are not willing to discuss or reply with an answer to my question scenario. You know very well the scenario I just explained with relative motion shows simultaneous, so you choose to ignore the question and then reply back with present information which DOES not answer my question about the inaccuracy I deem.
    No.
    You are looking at as - Janus noted - a case where the relative speeds are low: I.e. the theory is "inapplicable" in such cases (to be more accurate, the results - as given by Einstein - are so small as to be insignificant).


    I have no idea how this relates to my question or is an answer to the inaccuracy or even what it means. Sounds Gibberish to be honest.
    It's quite simple.
    A quick look at the relevant Wiki page (which you appear to have not even tried) states: simultaneity – whether two spatially separated events occur at the same time – is not absolute, but depends on the observer's reference frame.

    Note that part about reference frame.
    Where relative speeds are low (or non-existent) the all bodies are in the same frame.
    At high relative speeds the are in different frames and THAT is when the theory comes into play.
    You - while persisting with your "example" are arguing that Einstein is wrong (when in fact the results are exactly as predicted) by completely ignoring cases where the effects come into play.

    Mod comment:
    In point if fact if - truly - you don't don't know how this relates to your question then the obvious conclusion is that you don't actually know what Einstein said about the relativity of simultaneity: in other words you're arguing against something you don't understand and haven't looked at.
    Or, possibly, you're just trolling...
    I do not think the relative speed of c is slow, I added two inertia reference frames in my scenario. Perhaps I should change the question to about two different ticking clocks, then I may get an answer from you.

    Observer (A) is an equal distance apart from the Sun as Observer (B) , the Sun is in the middle. For purposes of the question, the Observers rotate around the Sun and remain an equal distant apart retaining a linearity between them. (no speed mentioned)


    The observers are both exactly 149.6 million km from the sun apart, r1=149.6 million km , r2=149.6 million km

    Both observers have time dilated clocks relative to each other.


    The time it takes for the light to reach observer 1 is 8 minutes and 24 seconds (approx), If the Sun was to explode it would take 8 minutes and 24 seconds for observer 1 to see this.


    Can you please answer , how long does it take for observer 2 to see the sun exploding?


    Now you have a bigger problem to deal with and answer, are you saying observer two with the slower ticking clock is going to measure the speed of light differently to observer 1?

    Observer 1 : observes c/dx

    Observer 2: observes c/dx


    light clocks remain very accurate when the distance is constant and there is no length contraction.



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    Quote Originally Posted by coldshoulder View Post
    I do not think the relative speed of c is slow
    There is no "relative speed of c" in your scenario.

    I added two inertia reference frames in my scenario.
    Not really.
    As I said: the relative speeds are low, thus the frames aren't that distinct (as far as simultaneity is concerned - i.e the variation in observed time is very small).

    Observer (A) is an equal distance apart from the Sun as Observer (B) , the Sun is in the middle. For purposes of the question, the Observers rotate around the Sun and remain an equal distant apart retaining a linearity between them. (no speed mentioned)

    In other words nothing whatsoever to do with what Einstein said.

    Both observers have time dilated clocks relative to each other.
    If there's no speed mentioned then from whence comes the dilation?

    Now you have a bigger problem to deal with and answer, are you saying observer two with the slower ticking clock is going to measure the speed of light differently to observer 1?
    What?
    ALL
    observers measure the speed of light to be the same value.

    light clocks remain very accurate when the distance is constant and there is no length contraction.
    No length contraction? Yet you stated that there's time dilation. The one doesn't happen without the other.
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    I do not think the relative speed of c is slow
    There is no "relative speed of c" in your scenario.

    I added two inertia reference frames in my scenario.
    Not really.
    As I said: the relative speeds are low, thus the frames aren't that distinct (as far as simultaneity is concerned - i.e the variation in observed time is very small).

    Observer (A) is an equal distance apart from the Sun as Observer (B) , the Sun is in the middle. For purposes of the question, the Observers rotate around the Sun and remain an equal distant apart retaining a linearity between them. (no speed mentioned)

    In other words nothing whatsoever to do with what Einstein said.

    Both observers have time dilated clocks relative to each other.
    If there's no speed mentioned then from whence comes the dilation?

    Now you have a bigger problem to deal with and answer, are you saying observer two with the slower ticking clock is going to measure the speed of light differently to observer 1?
    What?
    ALL
    observers measure the speed of light to be the same value.

    light clocks remain very accurate when the distance is constant and there is no length contraction.
    No length contraction? Yet you stated that there's time dilation. The one doesn't happen without the other.
    I am sorry but you sound really confused in your answers and I can only think you are winging it rather than knowing the subjects.

    Do you understand that in different inertia reference frames where the mass of the main bodies are different, clocks tick at different rates?

    Do you understand the constant speed of light in a vacuum?

    I will try to take this a bit slowly for you , I hope you do not feel offended but that is what your posts are making me think, that your knowledge is limited.

    Light will take the same amount of time to travel two equal radius, on a circle that had rotating bodies, the radius remains constant, if I rotated the bodies around the circle at the near speed of light, it would still make no difference to how long the light took to travel from the central point to the outer rim of the circle.

    All observers travelling around the circle at an equal radius from the center will measure the speed of light to be constant and they would all measure it to be the same speed in a vacuum. The scenario is an invariant and all observers travelling the circle see the star at the center exploding at the same time, i.e simultaneous.


    This is how sight and light works, so regardless of what the clocks tick at, the event is seen simultaneous in this scenario.
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    My knowledge is surely very limited but my mind is boggling at the scenario of bodies moving in a circle around an exploding star (or anything)at "near the speed of light"

    I think it is an unrealistic scenario
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  29. #28  
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    Quote Originally Posted by coldshoulder View Post
    I am sorry but you sound really confused in your answers and I can only think you are winging it rather than knowing the subjects.
    Crap.
    You persist in making unrelated , or incoherent, posts.
    Where is the "relative speed of c" in your scenario?

    Do you understand that in different inertia reference frames where the mass of the main bodies are different, clocks tick at different rates?
    Mass isn't related "inertial reference frame".

    Do you understand the constant speed of light in a vacuum?
    You're asking me this after also asking "are you saying observer two with the slower ticking clock is going to measure the speed of light differently to observer 1?"?

    I will try to take this a bit slowly for you , I hope you do not feel offended but that is what your posts are making me think, that your knowledge is limited.
    Given that so far you've managed to make incorrect statements about what relativity of simultaneity is along with "I have no idea how this relates to my question or is an answer to the inaccuracy or even what it means" and "Sounds Gibberish to be honest" it's obvious that you're not in a position to ascertain that.

    Light will take the same amount of time to travel two equal radius, on a circle that had rotating bodies, the radius remains constant, if I rotated the bodies around the circle at the near speed of light, it would still make no difference to how long the light took to travel from the central point to the outer rim of the circle.
    That would depend who's observing, wouldn't it?

    The scenario is an invariant and all observers travelling the circle see the star at the center exploding at the same time, i.e simultaneous.
    See below.

    This is how sight and light works, so regardless of what the clocks tick at, the event is seen simultaneous in this scenario.
    I fail to see how your scenario is an illustration of any problem. If the the observers are on the planets in orbit then their relative speeds are zero [1], hence obviously it's "simultaneous" for them. If there's an observer not on those planets then, given the different reference frames, it's not simultaneous.

    1 Well not really but...
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    Quote Originally Posted by geordief View Post
    My knowledge is surely very limited but my mind is boggling at the scenario of bodies moving in a circle around an exploding star (or anything)at "near the speed of light"

    I think it is an unrealistic scenario
    Most of relativity is unrealistic scenarios, but most of the thoughts are accepted although quite a bit of the thinking is unrealistic. I stand by statement about the inaccuracy of simultaneity.
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    Guys, you're wasting your time on him... It's in the bullshit bin, let it rot...
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    Quote Originally Posted by coldshoulder View Post
    Most of relativity is unrealistic scenarios, but most of the thoughts are accepted although quite a bit of the thinking is unrealistic.
    Except that they've been verified time and time again in the real world.

    I stand by statement about the inaccuracy of simultaneity.
    You're wrong. Simple as...
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    Most of relativity is unrealistic scenarios, but most of the thoughts are accepted although quite a bit of the thinking is unrealistic.
    Except that they've been verified time and time again in the real world.

    I stand by statement about the inaccuracy of simultaneity.
    You're wrong. Simple as...
    You saying I am wrong without explaining why I am wrong is not showing why i am wrong. Are you saying my scenario is not a simultaneous view of event?

    Quite clearly you are avoiding the questions I am asking .
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    Quote Originally Posted by PhDemon View Post
    Guys, you're wasting your time on him... It's in the bullshit bin, let it rot...
    A typical reply from somebody who has no answer.
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  35. #34  
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    Nope, just a frustrated reply from someone who is sick of fantasy physicists that don't know their arse from a hole in the ground, but know they are right and everyone else is wrong... Asses like you are ten a penny and we're sick of them.
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  36. #35  
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    Quote Originally Posted by coldshoulder View Post
    You saying I am wrong without explaining why I am wrong is not showing why i am wrong.
    Apart from the fact that you haven't put forward any argument to show that Einstein is wrong (other than incredulity) the FACTS (the aforementioned real life) shows that you are wrong.

    Are you saying my scenario is not a simultaneous view of event?
    Can you read?

    Quite clearly you are avoiding the questions I am asking .
    Actually you're the one avoiding questions:
    Where is the "relative speed of c" in your scenario?
    That would depend who's observing, wouldn't it?, and
    Which part of "simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case" in Janus' reply did you not understand?

    Further - as noted several times - your scenario doesn't address the point made by Einstein (i.e. high relative speeds).

    Countdown: 3.
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    Quote Originally Posted by PhDemon View Post
    Nope, just a frustrated reply from someone who is sick of fantasy physicists that don't know their arse from a hole in the ground, but know they are right and everyone else is wrong... Asses like you are ten a penny and we're sick of them.

    A very strange response, I have not used or mentioned anything other than Physics and present information. I have presented no new information but asked questions about a scenario. There was no fantasy in any of my posts or subjective thought, quite the contrary and objective.
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    The fact you think that just makes my point, you'll be gone soon :shrug:
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    You saying I am wrong without explaining why I am wrong is not showing why i am wrong.
    Apart from the fact that you haven't put forward any argument to show that Einstein is wrong (other than incredulity) the FACTS (the aforementioned real life) shows that you are wrong.

    Are you saying my scenario is not a simultaneous view of event?
    Can you read?

    Quite clearly you are avoiding the questions I am asking .
    Actually you're the one avoiding questions:
    Where is the "relative speed of c" in your scenario?
    That would depend who's observing, wouldn't it?, and
    Which part of "simultaneity seems absolute when dealing with low speeds, but as the speeds increase, it becomes apparent that this is not the case" in Janus' reply did you not understand?

    Further - as noted several times - your scenario doesn't address the point made by Einstein (i.e. high relative speeds).

    Countdown: 3.
    Countdown 321 ban ?

    I addressed the problem you mentioned when I made my orbits around the circle the near speed of light.
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    Quote Originally Posted by PhDemon View Post
    The fact you think that just makes my point, you'll be gone soon :shrug:
    Quite clearly you are a spod.
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  41. #40  
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    Quote Originally Posted by coldshoulder View Post
    A very strange response, I have not used or mentioned anything other than Physics and present information.
    This would be false.
    You've ignored (or dismissed) "present information" by denying the relativity of simultaneity.

    There was no fantasy in any of my posts or subjective thought, quite the contrary and objective.
    Fantasy: Einstein was wrong.
    Subjective: "I don't think it's..." and "does not seem..." accurate.
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  42. #41  
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    ...and you're a troll (hopefully a banned one very soon).
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  43. #42  
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    Quote Originally Posted by coldshoulder View Post
    I addressed the problem you mentioned when I made my orbits around the circle the near speed of light.
    Except that since both (all?) planets are going at c where's the relative difference?
    "Observers rotate around the Sun and remain an equal distant apart" = no relative speed.
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    I addressed the problem you mentioned when I made my orbits around the circle the near speed of light.
    Except that since both (all?) planets are going at c where's the relative difference?
    I never said they were all travelling at c. Ok, planet one travels at 0.5c and planet two travels at 0.75c, if this makes you happier. However it still does not affect how long the light takes to travel the radius to either planet from the central star.
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    Quote Originally Posted by PhDemon View Post
    ...and you're a troll (hopefully a banned one very soon).
    A troll? really? this thread as just gone live on a political forum , I would be careful what you say and how you treat new members if I was you.
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  46. #45  
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    Quote Originally Posted by coldshoulder View Post
    I never said they were all travelling at c.
    "Relative speed of c".

    Ok, planet one travels at 0.5c and planet two travels at 0.75c, if this makes you happier. However it still does not affect how long the light takes to travel the radius to either planet from the central star.
    According to which observer?
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by coldshoulder View Post
    I never said they were all travelling at c.
    "Relative speed of c".

    Ok, planet one travels at 0.5c and planet two travels at 0.75c, if this makes you happier. However it still does not affect how long the light takes to travel the radius to either planet from the central star.
    According to which observer?
    The Sun is our central reference frame, the two planets are rotating the sun like the hands of a clock. The radius (r) between the sun and planets is constant, the sun explodes, observer one sees the sun explode 8 minutes and 24 seconds after is explodes, observer 2 observes the sun explode in ?


    C is constant so the answer is 8 minutes 24 seconds

    Both planets observe the event simultaneous ?
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  48. #47  
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    Quote Originally Posted by coldshoulder View Post
    A troll? really?
    As pointed out earlier, either a troll or someone who - despite not knowing what he's talking about - thinks Einstein was w rong.

    this thread as just gone live on a political forum
    Because...?

    I would be careful what you say and how you treat new members if I was you.
    Yeah, let me think...
    An established member with a record of knowing his science vs a (possible) troll (failing that a crank who can't formulate an argument and doesn't understand what he's arguing against). I wonder which way that would go.
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  49. #48  
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    A troll? really? this thread as just gone live on a political forum , I would be careful what you say and how you treat new members if I was you.
    Why? We don't want to encourage nutters... I'm helpful to those willing to learn, you talk shit, you get shit :shrug:
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    Quote Originally Posted by PhDemon View Post
    A troll? really? this thread as just gone live on a political forum , I would be careful what you say and how you treat new members if I was you.
    Why? We don't want to encourage nutters... I'm helpful to those willing to learn, you talk shit, you get shit :shrug:
    So you are saying the constant of light is chit, you are saying vector analysis is chit, I do not really think I am the nutter here when I am using all present information.
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  51. #50  
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    Quote Originally Posted by coldshoulder View Post
    C is constant so the answer is 8 minutes 24 seconds
    Both planets observe the event simultaneous ?
    No.
    You are - again - ignoring the fact that time differs for observers with high relative speeds.
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  52. #51  
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    Quote Originally Posted by coldshoulder View Post
    So you are saying the constant of light is chit, you are saying vector analysis is chit, I do not really think I am the nutter here when I am using all present information.

    That's not what he said.
    By the way: decision made.
    Bye.
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  53. #52  
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    Quote Originally Posted by coldshoulder View Post


    I have asked the question in an understandable manner, it is no more than a question, I don't understand why such hostile treatment to a new member. I do not think I will be participating in this forum very much.


    Do all planets exist in the present ?

    Does light take time to arrive at your eyes?

    If both answers are yes, then Simultaneity is not accurate.
    The problem here is that the effect you think Einstein was talking about is not the actual effect he was referring to. If a light flash is 300,000 km from me and 600,000 km from someone else( with both of us at rest with respect to the flash), then, yes, he will see that flash ~1 sec after I do. But that is not what Einstein was referring to when he said that not all observers will agree on the simultaneity of events. He was not saying that, in the last example, that because the two observers saw the flash one second apart that they would say that the flash occurred at different times.

    Einstein was referring to something else. What he was referring to is what observers would determine about the simultaneity of events when they(the observers) have a relative motion to each other.
    So for example, if I am standing exactly halfway between and at rest with respect to two light flashes which are 600,000 km apart and you see the flashes at the same time, you know that the flashes actually occurred ~1 sec before you saw the light. But you also know that it took an equal amount of time for the light of each flash to reach you and you are able to determine that the flashes them occurred simultaneously with each other. You know this because you know that the light coming at you from each flash is travels at the same speed and they started at the same distance from you.

    But let's say that some other observer is traveling at some high speed in the direction going from one flash to the other. He passes you at the very instant you see the light from the flashes, Thus he also sees the light from both flashes at that same instant. But what does this tell you about when the flashes originated?
    First you have to consider a particular aspect of light speed. Light always travels at c relative to you as measured by you. The speed you would measure it traveling with respect to yourself does not matter on either the source's motion or your own. If a light source is at rest with respect to you, you will measure its light as moving at c relative to yourself. If the source starts to move towards or away from you, you would measure that light as moving at c with respect to you. If you start to moving toward or away from the source, you will still measure its light as moving at c with respect to you. What this means is that the time it takes for the light to reach you from the source depends on how far it was from you when the light was emitted and not how far apart you are when you see the light. ( of course if you are at rest with respect to the source, these two distances will be the same.)
    So now we can consider our second observer:
    At the moment he passes you he is halfway between the two flashes, But when they were emitted, he was not. Since we know that the light from each flash had to be emitted at some time before he passed you, he had to be closer to one of the source flashes than the other when they were emitted. If the time it takes for the light to travel from source to observer depends on their distance apart at the time of emission, it had to take longer for the light from one flash to reach him than it did for the other. But he saw the flashes at the same time just like you did. And while you were able to determine that the flashes were emitted simultaneously because the sources were equally distant from you at emission, he has to determine that the flashes were not emitted simultaneously because while he sees the flashes simultaneously, the light from each flash did not take the same amount of time to reach him from the moment of emission.

    Einstein demonstrated this with a different example. In his example, the flashes originate at equal distances from each observer, but one sees them simultaneously and the other doesn't (in his example, the observers are not co-located when they see the flashes), but he conclusion is the same. One observer sees the flashes that originated from points equally distant from him and concludes that they are simultaneous, while the other sees the same flashes (also originating at equal distances from him) at different times and concludes that they were emitted at different times.

    Relativity of Simultaneity is not just a result of light speed being finite, but being finite and invariant.
    Another stumbling block when it comes to learning about Relativity is to put too much importance to light itself. It isn't the light per se that is important, it is the speed at which it travels (c). This invariant speed is something that is built into the very reality of the Universe, and has a profound effect on its fundamental operation and its existence has any effect even at speeds below c. Even if there were no light or anything that traveled at c, you would still get Relativity ruling how the universe works. Again, it comes back to the round Earth example, at low speeds the effect of the existence of the invariant speed of c is negligible, and almost impossible to measure, but once speeds start to increase significantly, the effects start to become noticeable. One example is how velocities add together. If you are riding down the road at 100 kph and throw a ball forward at 50 kph, you would expect that the ball would be moving at 100+50 = 150 kph with respect to the road, however, this is not the case, it would actually be moving at 149.99999999999903549382716050003 kph with respect to the road. This is such a small difference from 150 kph, that's it's no wonder that it wouldn't be noticed. However, if you were to increase the speeds being added to 0.5c and 0.25c, the answer becomes 0.66666666666... c, which is quite different from the 0.75c you would get by adding them directly together.

    The point is that before Einstein we thought the rules of the universe worked in certain ways, and these rules (like adding velocities directly) could be extended to all velocities. As it turned out, those rules only ended up giving close approximates to the correct answer over a limited range of speeds.
    "Men are apt to mistake the strength of their feelings for the strength of their argument.
    The heated mind resents the chill touch & relentless scrutiny of logic"-W.E. Gladstone


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