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hutchphd
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I, for one, do not understand the distinction you are trying to create. Perhaps you could succinctly restate your question.
Ok! I am simply asking how is “right everywhere” is same as “right from everywhere”?hutchphd said:I, for one, do not understand the distinction you are trying to create. Perhaps you could succinctly restate your question.
You can see in the logic I had put a question mark. The math says only “right from everywhere” not “right everywhere”.mark2142 said:This does not happen. We can write the correct laws using the new coordinates. There is no absolute space and origin from which the laws are right. So it’s right everywhere or from everywhere ?
Take a piece of equipment and study it. Move it somewhere and study it again from a distance. Is it working the same? Repeat and repeat until you are convinced that the laws you have that describe the instrument are "right everywhere".mark2142 said:Ok! I am simply asking how is “right everywhere” is same as “right from everywhere”?
It’s already been explained before in many posts and I already know the laws don’t change upon displacement. I want to understand the proof that Feynman gave. I am unable to follow from math that laws don’t change upon displacement. The math is proving the law is same for different observers.Ibix said:Take a piece of equipment and study it. Move it somewhere and study it again from a distance. Is it working the same? Repeat and repeat until you are convinced that the laws you have that describe the instrument are "right everywhere".
Bring the equipment back to you. Now you move somewhere and study it again from a distance. The laws governing your function don't change (we just established that) and the equipment hasn't moved. Thus the results will be the same and the laws are "right from everywhere".
mark2142 said:It’s already been explained before in many posts and I already know the laws don’t change upon displacement. I want to understand the proof that Feynman gave. I am unable to follow from math that laws don’t change upon displacement. The math is proving the law is same for different observers.
Ibix said:... So Feynman is proving that his model of the laws of physics are translation invariant and hence his equipment is predicted to be translation invariant. He does not prove (and you cannot prove) that this is a correct model of reality, but it's been an accurate model every time so far.
I think the only difference is how you interpret the offset, ##a##. Is it the distance between two coordinate system origins, or is it the negative of the x displacement between two pieces of identical equipment measured in the same coordinate system? (I may have incorrectly assigned the negative sign there, so beware.) Depending which way you interpret it you are proving either.mark2142 said:The math is proving the law is same for different observers.
(Now this means that there exists a way to measure x, y, and z on three perpendicular axes, and the forces along those directions, such that these laws are true.)Ibix said:Depending which way you interpret it you are proving either.
By doing physics theory in the classroom and experiments in the lab.mark2142 said:Can you tell how do we measure and write newtons law?