DimaMazin Posted May 31, 2013 Posted May 31, 2013 Fast traveler escapes from us.If acceleration moved clock of the traveler into our frame(motionless relatively of us) then how do we and the traveler define scalar slowing or rapidness of time of the clock relatively of the traveler? -2
J.C.MacSwell Posted June 5, 2013 Posted June 5, 2013 Fast traveler escapes from us.If acceleration moved clock of the traveler into our frame(motionless relatively of us) then how do we and the traveler define scalar slowing or rapidness of time of the clock relatively of the traveler? In SR: As the clock reaches motionlessness in our frame, it measures the rate of time passage of our frame...we would observe/calculate it as having sped up to match our rate from a previously slower pace. Since it was previously slower, less time would have passed for it. The reading on it would show less time lapsed, since the time it had escaped from us, than any clock of our own that had remained stationary in our frame. -1
DimaMazin Posted June 7, 2013 Author Posted June 7, 2013 In SR: As the clock reaches motionlessness in our frame, it measures the rate of time passage of our frame...we would observe/calculate it as having sped up to match our rate from a previously slower pace. Since it was previously slower, less time would have passed for it. The reading on it would show less time lapsed, since the time it had escaped from us, than any clock of our own that had remained stationary in our frame. Do you think time is scalar only after trip?
ajb Posted June 7, 2013 Posted June 7, 2013 (edited) Do you think time is scalar only after trip?What do you mean by scalar? Time is "scalar" in the sence that it is one number, but it is not Lorentz invariant. I think you will need to be much clearer with your opening question. Edited June 7, 2013 by ajb
xyzt Posted June 8, 2013 Posted June 8, 2013 (edited) In SR: As the clock reaches motionlessness in our frame, it measures the rate of time passage of our frame...we would observe/calculate it as having sped up to match our rate from a previously slower pace. Since it was previously slower, less time would have passed for it. The reading on it would show less time lapsed, since the time it had escaped from us, than any clock of our own that had remained stationary in our frame. The Op's question made absolutely no sense, so I don't see how you could give an answer. Would you mind trying to put the above in a mathematical formalism, after all , the language of physics is math. Ah, I see your "answer", you simply retaliated with feedback. Edited June 8, 2013 by xyzt -2
DimaMazin Posted June 8, 2013 Author Posted June 8, 2013 The Op's question made absolutely no sense, so I don't see how you could give an answer. Answer can be correcting the wrong question. For example 1)Nohow 2)Relativity doesn't define 3)Scalar time doesn't exist for relative travelers in relativity -1
DimaMazin Posted June 10, 2013 Author Posted June 10, 2013 (edited) What do you mean by scalar? Scalar time is one number to one clock for any observer in any frame. Edited June 10, 2013 by DimaMazin
ajb Posted June 11, 2013 Posted June 11, 2013 Scalar time is one number to one clock for any observer in any frame. Every observer has his "own clock" which defines his notion of proper time. But this is not a global and invariant notion of time.
O'Nero Samuel Posted June 19, 2013 Posted June 19, 2013 Every observer has his "own clock" which defines his notion of proper time. But this is not a global and invariant notion of time. "Every observer has his own clock"? I think that was too ambigous. Take for instance two observer having the same frame of reference, would they both have their own clock? I think you needed to state that every observer on a frame of reference has his own notion of proper time relative to every other obeserver in some other frame of reference moving with some relative velocity to the other. Please do correct me if I am wrong. I believe the original question of this post means to say that if an observer in a frame of reference reduces its speed to match with that of some other frame of reference, would their time synchronise? If then this is the question; then the answer would depend on whether both frame of references are moving in the same direction. If they are, then their time frame would synchronise; but if not then there would be a relative velocity, and therefore a minute laps in the time of both observer.
ajb Posted June 19, 2013 Posted June 19, 2013 "Every observer has his own clock"? I think that was too ambigous. Take for instance two observer having the same frame of reference, would they both have their own clock?So if two near by observers are comoving i.e. stationary wrt each other, then they can agree on the duration of events.I think you needed to state that every observer on a frame of reference has his own notion of proper time...Okay so by observer we really mean an inertial frame of reference, and with respect to any inertial frame we have the notion of a proper time. Really we are being a little slack here, but this can all be defined carefully. ...relative to every other obeserver in some other frame of reference moving with some relative velocity to the other.Why is the proper time relative to any other observer? The proper time is the time measured between two events that sit on the world line of an inertial observer. What is true is that two observers will generally disagree on the time between two events.
O'Nero Samuel Posted June 19, 2013 Posted June 19, 2013 So if two near by observers are comoving i.e. stationary wrt each other, then they can agree on the duration of events.Okay so by observer we really mean an inertial frame of reference, and with respect to any inertial frame we have the notion of a proper time. Really we are being a little slack here, but this can all be defined carefully.Why is the proper time relative to any other observer? The proper time is the time measured between two events that sit on the world line of an inertial observer. What is true is that two observers will generally disagree on the time between two events. "...world line of inertial observer"?! What was that supposed to mean? Relativity, if you still believe its laws, says that every initial frame is correct relative to the other. In other words, there is no, so to speak, super-correct frame of reference: if that was what you meant by world line of inertial observer. Time and the spontaneity of events depends on the state of the frame of reference from which the observer makes his observation. Time is relative and there is nothing as an absolute time frame.
ajb Posted June 19, 2013 Posted June 19, 2013 "...world line of inertial observer"?! What was that supposed to mean?A particle, which I assume an inertial observer to be, will track out a line in 4 d Minkowski space-time. The proper time is then analgous to the arc-length of the path traced out by a massive particle. This is different to the coordinate time, which can be considered as the time between events as measured by some far off observer. Relativity, if you still believe its laws, says that every initial frame is correct relative to the other.Poor language here. What special relativity says is that there are no prefered frames of reference, only a special class called the inertial frames. The point is that any inertial frame of reference can be used to describe (non-gravitational) physics and none of these is prefered.In other words, there is no, so to speak, super-correct frame of reference: if that was what you meant by world line of inertial observer.This is not what I mean. However, every inertial observer can define his proper time. This is the time he will measure, but this is no way some "special correct duration" but will be specific to the observed and his path in space-time.Time and the spontaneity of events depends on the state of the frame of reference from which the observer makes his observation. Time is relative and there is nothing as an absolute time frame.Right, which is what we have all been saying. As an aside, I don't like the nomenclature proper time or proper length etc as they suggest some special invariant status. However, the terms are in common use...
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