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# Relativity Wheel

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Craig - There are other types of geometric objects defined on Minkowski space, not simply 4-vectors.  The following are examples: the metric tensor, the Faraday tensor (aka EM tensor), the stress-energy-momentum tensor and the angular momentum density tensor readily come to mind.

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You are so funny!

The way that time dilates and length contracts are physically identicle! The fact that they have different names doesn't mean a thing. :) They're both distance shortening and they both happen in unsion which is why this works.

Actually... not quite.

time and length are NOT identical.

time * c * i   and length are identical, where c is the speed of light and i is the square root of -1.

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Pyrotex - You're right in that length contraction and time dilation are very different. Not only do they have very different physical meanings but their relationship between two frames S and S' are

T' = T/sqrt[1- v^2/c^2]

L' = L*sqrt[1- v^2/c^2]

Where T = proper time and L = proper length. So as anybody can readily see, they're very different. As I've said many times, A-wal's grasp of this subject is very weak. This is just another example of it.

Edited by Pmb
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:) My grasp of relativity is fine thank you. your insistence that time dilation and length contraction occur at different rates despite posting the equations (twice now) that show they don't is just making you look all the more stupid. I'll make this as simple as I can for you.

The fact that the speed of light is constant for every inertial observer means that if two objects are in motion relative to each other then they each have to measure the other as length contracted and/or time dilated in order for the speed of light to be the same for both of them. If length in space (in the straight line between them) contracts then the other observer is covering less distance and if time dilate they are taking longer to cover the distance. If both are happening together then the effect is squared because velocity is a measurement of distance over time.

If two inertial observers in motion relative to each other measure length contraction as halving the length of space of the other object then each measure time dilation also halving the rate that the other object is moving through time. If they measure length contraction dividing the length of space of the other object by four then they also measure time dilation dividing the speed that the other object is moving through time by four. Time dilation and length contraction always happen at the exact same rate, making the two processes physically equivalent.

Do you understand?

Why did you move this topic to the strange claims section Santus? CraigD confirmed that this does work, you can express the relationships in time and space of objects in motion relative to each other using just two dimensional angles.

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