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Old Nov 1st 2016, 06:42 AM   #21
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I thought your spring was an analogy for gravity - if it's not, then what what did you intend by it? Are you trying to say that if you attach a spring between two objects, and one is "absolutely" stationary, the spring will stretch at the other end first? I don't think that's true - unless the spring itself is also "absolutely" stationary.
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Old Nov 1st 2016, 08:45 AM   #22
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The first thing I prove when I mentioned about the car and the rock is the relative motion between 2 objects does exist a unique velocities between them. The spring is just like an indicator for testifying these unique velocities. Then when I prove the existence of unique velocities between 2 objects, I can generalise the principle to every object in the universe such as with the earth and the mars. I come to the conclusion of existence of unique velocities between the earth and the mars in their absolutely inertial state. That's the order of the arguments
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Old Nov 1st 2016, 09:10 AM   #23
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Velocities between any two objects are are not always unique. For example, if two cars pass you as you stand next to a road, and both cars go by at 20 MPH, they both have the same velocity relative to you - their velocities relative to you are not unique.
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Old Nov 1st 2016, 09:40 AM   #24
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I said 'unique', that means only one of the cases does exist when the cars pass each other with speed 70miles/h:
case1: car1 - 30miles/h, car2 - 40miles/h
case2: car1 - 40miles/h, car2 - 30miles/h
case3: car1 - 70miles/h, car2 - 0
case4: car1 - 0, car2 - 70miles/h
... so on
By the way, we can pull the cars out of the earth's gravity, push them into outerspace and let them drift in space. In this case, the gravitational forces does not affect the spring's stretching.
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Old Nov 1st 2016, 10:16 AM   #25
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Originally Posted by HaiNguyen View Post
I said 'unique', that means only one of the cases does exist when the cars pass each other with speed 70miles/h:
case1: car1 - 30miles/h, car2 - 40miles/h
case2: car1 - 40miles/h, car2 - 30miles/h
case3: car1 - 70miles/h, car2 - 0
case4: car1 - 0, car2 - 70miles/h
... so on
Just so I'm clear on what you're to say: you are now talking about two cars that pass each other, at a relative speed of 70 MPH. You maintain that there is only one possibility of velocities for each car. I disagree. All of those cases are possible, simultaneously -- it all depends on the relative motion of the observer, or observers (who may not be in either car). An observer in car A sees car 1 = 0 MPH and car 2 = -70 MPH; an observer in car 2 sees car 1 = -70 MPH and car 2 = 0 MPH, an observer on the ground sees car 1 = +40 MPH and car 2 = -30 MPH, and an observer on another planet sees car 1 = 30,000 MPH and car 2 = 30,070 MPH. They're all correct, simultaneously.
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Old Nov 1st 2016, 10:20 AM   #26
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No, because the experiment with the spring can prove only one of them is true.
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Old Nov 1st 2016, 11:03 AM   #27
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As discussed earlier your spring doesn't prove anything. In each case it stretches between the observer and each car (or is it between the two cars?). Nothing is learned from that.

You have an opinion that goes against accepted laws of physics, and haven't been able to articulate very well any supporting evidence for that opinion. We will continue to disagree.

Last edited by ChipB; Nov 1st 2016 at 12:23 PM.
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Old Nov 1st 2016, 11:42 AM   #28
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I agree with you onething that we will disagree about this problem. So you keep your opinion, I keep mine.
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Old Nov 1st 2016, 12:19 PM   #29
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Originally Posted by HaiNguyen View Post
I agree with you onething that we will disagree about this problem. So you keep your opinion, I keep mine.
Science is about proof, not opinion. Your spring analogy has some serious flaws that can't be ignored just because you would like it to be so. Please review the (excellent) arguments that ChipB has been writing. He knows what he is talking about.

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Old Nov 1st 2016, 06:28 PM   #30
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Originally Posted by topsquark View Post
Science is about proof, not opinion. Your spring analogy has some serious flaws that can't be ignored just because you would like it to be so. Please review the (excellent) arguments that ChipB has been writing. He knows what he is talking about.

-Dan
The arguments of ChipB doesn't make any sense to me. I make my point clear. The disagreement is still be there.
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