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I have never claimed that an instant signal is sent.Well, I have said that if you press the two "reset" buttons on the clocks against one another it is one action and it is local to both clocks and, since it's the same act it is simultaneous with itself for all observers because the alternative would be a violation of causality.And I have said that , if you have two perfect clocks next to each other, set to "zero" at the same time, they will stay synchronised.And I have said that, if you move one of them, it will run slow, but if you move it slowly it will not lose much time (and someone kindly provided a table of how slow it would be).So, since you know how slow it is, you can allow for that.You keep going on about conventions; well I have tried to define mine. You keep telling me that the apparent speed depends on epsilon.I keep asking you if the apparent speed of light I measure will be consistent and, rather than saying yes or no, you keep telling me that instant messaging isn't possible.Well, I know that- and I never said it was.So, yet againIf I do the experiment of synchronising two clocks (next to each other) then moving them slowly then using them to time the arrival of a flash of light- with all the details I previously specified.And then I repeat it.Will I get the same answer twice?
The box #121;QuoteEinstein never considered the two way journey of light in his ideas . If he had , he would of known and realised that simultaneity is nothing to do with different now's or different rates of time.Do more research.1905 paper, par. 1, 2; A. Einstein:We have to take into account that all our judgments in which time plays a part are always judgments of simultaneous events.We have so far defined only an ``A time'' and a ``B time.'' We have not defined a common ``time'' for A and B, for the latter cannot be defined at all unless we establish by definition that the ``time'' required by light to travel from A to B equals the ``time'' it requires to travel from B to A.So we see that we cannot attach any absolute signification to the concept of simultaneity, but that two events which, viewed from a system of co-ordinates, are simultaneous, can no longer be looked upon as simultaneous events when envisaged from a system which is in motion relatively to that system.
Einstein never considered the two way journey of light in his ideas . If he had , he would of known and realised that simultaneity is nothing to do with different now's or different rates of time
You can simply put your reset button of the two clocks exactly in the middle, the time it takes the signal to travel to both clocks will be synchronous if the wires are the same length from each clock. , this will allow both of your clocks to start ''counting'' time , synchronous. However you don't need a clock to time the one way speed of light. You need a strobe set to one flash per second. You then need a detector distance x apart and the detector read out speed to be 5cm a second. This will firstly test that c is c. dx=dyok?
Quote from: Bored chemist on 19/08/2017 16:24:08You keep going on about conventions; well I have tried to define mine.So it's a convention. CASE CLOSED my first post stands correct. Good bye.
You keep going on about conventions; well I have tried to define mine.
Quote from: Thebox on 19/08/2017 17:57:10You can simply put your reset button of the two clocks exactly in the middle, the time it takes the signal to travel to both clocks will be synchronous if the wires are the same length from each clock. , this will allow both of your clocks to start ''counting'' time , synchronous. However you don't need a clock to time the one way speed of light. You need a strobe set to one flash per second. You then need a detector distance x apart and the detector read out speed to be 5cm a second. This will firstly test that c is c. dx=dyok?No.Sorry, but it's not OK.You can't synchronise two clocks unless they are in (essentially) the same place.And the rest makes no real sense.
The clocks have to be in the same place in order for "synchronisation" to make sense.If you are stood next to one clock a and you see the other as reading the same time , you might say they are synchronised.But if you go to the other and look back you will say that they no longer agree.Synchrony only exists locally.
Pity you didn't have time to answer my question before you went.
And he is talking about sight, think about it.
Quote from: Thebox on 19/08/2017 18:02:57And he is talking about sight, think about it. Most of our sensory input is via sight, and he surely thought about it. If you don't understand the theory, just say so. We are all ignorant of something.
According to the special theory of relativity, it is impossible to say in an absolute sense that two distinct events occur at the same time if those events are separated in space. For example, a car crash in London and another in New York, which appear to happen at the same time to an observer on Earth, will appear to have occurred at slightly different times to an observer on an airplane flying between London and New York. The question of whether the events are simultaneous is relative: in the stationary Earth reference frame the two collisions may happen at the same time but in other frames (in a different state of motion relative to the events) the crash in London may occur first, and in still other frames the New York crash may occur first. However, if the two events could be causally connected (i.e. the time between event A and event B is greater than the distance between them divided by the speed of light), the order is preserved (i.e., "event A precedes event B") in all frames of reference.
Quote from: Bored chemist on 20/08/2017 19:25:23The clocks have to be in the same place in order for "synchronisation" to make sense.If you are stood next to one clock a and you see the other as reading the same time , you might say they are synchronised.But if you go to the other and look back you will say that they no longer agree.Synchrony only exists locally.Only if you are using a crap clock such as the caesium atomic clock. It is the clock that is faulty not the synchronisation of time. You quite clearly ignore my notions , but if you accepted my notions and used the Planck light clock, then you would not have a problem of synchronising clocks to worry about .
Quote from: Bored chemist on 19/08/2017 20:43:37Pity you didn't have time to answer my question before you went.The answer is that if you repeat your experiment, you'll get the same result, and if the whole system has accelerated in between the original experiment and the repeat, you'll still get the same result. You will think you've kept the clocks in sync each time regardless of whether they are really still in sync or not.
If I was accelerating I'd know about it (in principle).I'm not.So, I should get the same answer each time.Right?
Quote from: Thebox on 20/08/2017 23:29:00Quote from: Bored chemist on 20/08/2017 19:25:23The clocks have to be in the same place in order for "synchronisation" to make sense.If you are stood next to one clock a and you see the other as reading the same time , you might say they are synchronised.But if you go to the other and look back you will say that they no longer agree.Synchrony only exists locally.Only if you are using a crap clock such as the caesium atomic clock. It is the clock that is faulty not the synchronisation of time. You quite clearly ignore my notions , but if you accepted my notions and used the Planck light clock, then you would not have a problem of synchronising clocks to worry about . The thing about, for example, a caesium clock, is that it tells the time.If your "clock" doesn't agree with it then it isn't really a clock.
My point was that even if you accelerate in between, you'll still get the same answer,
Quote from: Bored chemist on 22/08/2017 18:40:07If I was accelerating I'd know about it (in principle).I'm not.So, I should get the same answer each time.Right?Yes, you'll get the same answer each time. My point was that even if you accelerate in between, you'll still get the same answer, unless you try to account for the acceleration, at which point you could base things on the original frame of reference in which you were at rest and determine that the second measurement gives you a speed of light relative to the clocks that isn't c, or alternatively you might reassess your first measurement on the basis that you're now at rest, in which case you'll decide that your first measurement gave you a value different from c.
Quote from: David Cooper on 22/08/2017 20:40:41 My point was that even if you accelerate in between, you'll still get the same answer, SR clock synch is relative to the frame speed. If the frame increases speed, the clocks will be out of synch.
Well, that's nice.It means that, whatever epsilon may be, it doesn't matter.
Quote from: phyti on 23/08/2017 17:37:12Quote from: David Cooper on 22/08/2017 20:40:41 My point was that even if you accelerate in between, you'll still get the same answer, SR clock synch is relative to the frame speed. If the frame increases speed, the clocks will be out of synch. If you do the experiment, then accelerate, then do the experiment again, clearly doing the experiment again involves reuniting the clocks and making sure they're in sync before separating them again.____________________________________________________________________Quote from: Bored chemist on 23/08/2017 18:34:27Well, that's nice.It means that, whatever epsilon may be, it doesn't matter.It does matter, because whenever you do your experiment, you are using epsilon=1/2 without realising it.
If you do the experiment, then accelerate, then do the experiment again, clearly doing the experiment again involves reuniting the clocks and making sure they're in sync before separating them again.