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Old Aug 11th 2017, 01:42 PM   #11
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Originally Posted by AndrewS View Post
You still haven't answered my question.

If the ratio of clock rates is causing a problem then think of it as the ratio of clock speeds.
I can only assume this comment was aimed at some other poster since I have just told you that there is no such thing as a clock rate and substituting a synonym like speed doesn't change that.

So assuming you mean something I ask again

What do you mean by clock rate or clock speed?
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Old Aug 11th 2017, 02:20 PM   #12
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I am talking about the ratio of clock speeds that each observer measures, e.g. 0.99 and 1.01. A ratio of speeds is not a single speed in isolation.

As you won't answer any of my questions, is there anyone else who can explain why a ratio of clock speeds is causing so much difficulty?
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Old Aug 11th 2017, 02:55 PM   #13
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That's twice I have already asked you what you mean by a phrase that is not used in proper physics without reply.

That's four times I have told you where your misunderstandings of proper relativity Physics lie, again without response.

It remains a physical impossibility to reply to your question about ratios or other functions of a quantity you refuse to define since I don't know what you mean.
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Old Aug 11th 2017, 09:33 PM   #14
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Ok, I will have a go at this.

The problem is the concept of now or what is simultaneous. Its a slippery concept in the subject of SR (special relativity). Here are a couple of short videos that explain the problem of now or simultaneity.





Now I understand your dilemma with both clocks slowing down (according to each observer) when we would rather expect everyone to agree that one clock is running fast and the other slow or that there is no difference. What no one has mentioned yet is the whole reason we had to come up with such a strange result (namely that each sees the other person's clock slow down and that they are both right according to their own frame of reference which sounds like nonsense). That reason was the Michelson Morley experiment that showed that the speed of light is invariant and not subject to the speed of the light source. This is not true for sound waves such as the doppler effect of the changing pitch of a passing train horn.

So my challenge to @AndrewS is that if he thinks that Einstein misinterpreted Michelson Morley's results and supposes that erroneous interpretation lead to time dilation and length contraction of SR, is to see if he can come up with an alternative explanation of Michelson Morley's results that eliminates this problem. I have indeed thought about it myself but haven't been able to come up with a better way to explain the speed constancy of light than to say distances contract and time slows down for each and every inertial observer travelling at different velocities observing the same ray of light. However, who knows, maybe you, @AndrewS, will succeed where I have failed. Good luck :-)
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Old Aug 12th 2017, 03:29 AM   #15
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Thanks Kiwiheretic (what kept you?)

The most obvious solution is to suppose that EM light travels through the EM field that extends from every bit of matter and which fills the universe - even the emptiness of space. This is a somewhat superficial idea as we know that quantum effects are going on behind the scenes. Presumably I should say that light travels through the quantum field associated with matter. Every charged particle then has an effect on the path of a photon. The effect obviously diminishes with the square of distance, as does gravity. As far as the Earth is concerned we can say the field through which light moves is centred in the middle of the Earth.

There is more to it than I have discussed because of energy effects. However I would say MM found no directional differences that could be ascribed to the hypothetical ether because all their measurements were in the Earth's field. In other words the speed of light is constant with respect to the prevailing field but not to an observer moving with respect to the field. This means that the principle of relativity is also false.

The most important point about time dilation is that, in general, it is not symmetrical - as SR's assumption about relativity predicts it must be. In this way we can avoid all the paradoxes created by relativity. Energy and momentum are then conserved whereas they are not conserved between frames in SR - a lethal flaw in my opinion. As far as I know this interpretation is also consistent with experiments whereas SR's prediction of symmetrical time dilation has been disproved. It is also consistent with physicists' inability to demonstrate distance contraction.
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Old Aug 12th 2017, 11:56 AM   #16
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Originally Posted by AndrewS View Post
I will begin with a standard opening.

When two observers, A and B, move inertially in relation to each other, SR predicts they will each see each otherís clock has slowed down. Suppose the speed of Aís clock is x and the speed of Bís is y. A will know that x>y and B will know that x<y. If a mathematical proposition gave rise to this result it would obviously be considered to be false. So it is with SR. A quantity cannot simultaneously be both larger and smaller than something else. SR leads to logically inconsistent predictions and so it must be false.

Any comments so far?
SR is based on two postulates:

1) The laws of nature are the same in all inertial frames of reference.
2) The speed of light has the same value in all inertial frames of reference.

Given those two postulates all of SR follows. The predictions of SR have been tested to great precision.

Consider the following thought experiment: In A's inertial frame there is a baseball moving at 100 m/s, as measured by observer A, towards the inertial observer B who is moving away from observer A at 100 m/s.

According to A the baseball is moving at 100 m/s. According to B the baseball is at rest.

Do these facts also bother you?

It's rather simply to show the relative rate that clocks tick. See the derivation on my website at:

Time Dilation

There is absolutely no paradox here and there is also nothing a mathematician could or would object to.

By the way: if a < b and b < a then that's a contradiction and does not imply that a = b.

That could only be true if and only if a <= b and b <= a

where "<=" means "is less than or equal to"
"
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Old Aug 12th 2017, 12:10 PM   #17
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Originally Posted by AndrewS View Post
Thanks Kiwiheretic (what kept you?)

The most obvious solution is to suppose that EM light travels through the EM field that extends from every bit of matter and which fills the universe ...
Not sure what you are calling an EM field. You seem to be describing an ether based on your further comments or maybe you are referring to "elementary waves" (a controversial yet interesting theory by Jeff Boyd and Lewis Little)?

Every charged particle then has an effect on the path of a photon.
Where did you read that? I always understood photons to be electrically neutral.

There is more to it than I have discussed because of energy effects. However I would say MM found no directional differences that could be ascribed to the hypothetical ether because all their measurements were in the Earth's field. In other words the speed of light is constant with respect to the prevailing field but not to an observer moving with respect to the field. This means that the principle of relativity is also false.
Is the sun also in the earth's field? Or does it have its own ether field? Are you suggesting if we take measurements, using scientific instruments, from a spacecraft far enough away from earth that we would detect a different speed of light?

The most important point about time dilation is that, in general, it is not symmetrical - as SR's assumption about relativity predicts it must be. In this way we can avoid all the paradoxes created by relativity. Energy and momentum are then conserved whereas they are not conserved between frames in SR - a lethal flaw in my opinion. As far as I know this interpretation is also consistent with experiments whereas SR's prediction of symmetrical time dilation has been disproved. It is also consistent with physicists' inability to demonstrate distance contraction.
So if you don't believe in symmetry of relativity do you believe that some frames of reference are special? Do you believe that the earth is a special frame of reference because of a hypothesized ether field generator buried in the centre of the earth?
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Old Aug 12th 2017, 10:33 PM   #18
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By EM field I just mean the field surrounding charged particles. But as I say, there is more going on than we can measure in the EM field. Midway between two protons there may be no net EM force, but there is still a "quantum vacuum" and this underlies the EM field.

I don't think I have read this anywhere, but photons represent disturbances in the EM field.

Yes the Sun and Earth are in each other's field. It is analogous to gravity, but again, while there is a point between two masses where the gravitational forces cancel, the quantum field does not. I don't think it helps to call it an ether. This harks back to a previous misunderstanding, and physics is bedevilled by old misunderstandings. (The most damaging of which is the principle of relativity which Copernicus mentioned.) The speed of light is constant relative to the field.

The only frame which is special for an observer in an absolute sense is the one which is at rest with the observer's visible universe. This can be defined by the CMBR.
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Old Aug 12th 2017, 11:02 PM   #19
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Originally Posted by Pmb View Post
By the way: if a < b and b < a then that's a contradiction and does not imply that a = b.
"
Please do not ascribe blatantly false statements to my posts. I am aware that a<b and b<a is a contradiction, that was the whole point of my argument. I am also aware of SR's postulates.

If SR's predictions have been confirmed, to what precision has distance contraction been measured?
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Old Aug 13th 2017, 12:31 AM   #20
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Originally Posted by AndrewS View Post
Please do not ascribe blatantly false statements to my posts. I am aware that a<b and b<a is a contradiction, that was the whole point of my argument.
You should be more careful in what you're reading since I never said anything of the kind directly to you. I was referring to studiot's comment
In maths we can say that a < b and b < a are only true iff and only if a = b

Originally Posted by AndrewS View Post
I am also aware of SR's postulates.
You may know the postulates but you sure don't demonstrate any understanding of what they imply, i.e.


Originally Posted by AndrewS View Post
Suppose the speed of A’s clock is x and the speed of B’s is y. A will know that x>y and B will know that x<y. If a mathematical proposition gave rise to this result it would obviously be considered to be false. So it is with SR.
That statement is blatantly false and shows a very poor understanding of relativity. I'm not only a physicist but a mathematician as well and I know your conclusion is quite wrong. I gave you an example of how wrong your thinking is above when I gave that example of speed, which you so cleverly ignored so you wouldn't have to admit you are wrong. Observers in different frames of reference measure different things. In the example I gave a baseball had a speed of 100 m/s as measured by one observer an a speed of zero as measured by another observer.

And time dilation does not merely refer to one an observer "sees" but what an observer measures. And its wrong to speak of the "speed" of a clock. The correct phrase is "rate" i.e. clocks at rest in frame S' are measured to run at a different rate that clocks at rest in frame S.

Originally Posted by AndrewS View Post
If SR's predictions have been confirmed, to what precision has distance contraction been measured?
That statement shows a poor understanding of how science works. Being confirmed does not mean the same thing as being verified. Confirmed means to establish the truth of something. Being verified means that something has been shown to be consistent with something. The postulates of SR have been verified. Laws of physics can never be shown to be true. They can only show to shown to be false or shown to be consistent with experiment. That's how science works. And you don't appear to grasp those things.


There's a difference between being something being directly measured and something being verified. Length contraction has been verified in several ways. For a list of some of them see
https://en.wikipedia.org/wiki/Length..._verifications

I've been ignoring your posts to date because you show such poor grasp of physics that its a waste of time to talk to you about them. You make totally wrong statements as if there were the word of God, like that nonsense about magnetic flux. It's time for you to go into my ignore list. Bye bye.
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Last edited by Pmb; Aug 13th 2017 at 12:35 AM.
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