I am new to the topic of special relativity. Having read a bit of Feynman and googling for answers I am still a bit lost. While I have an aptitude for logic, it does not extend quickly into physics or maths. So quite likely I am barking up the wrong tree and about to demonstrate my ignorance but here goes...(adsbygoogle = window.adsbygoogle || []).push({});

Special relativity start by saying there is no absolute velocity. No stationary frame of reference. Only relative positions to other frames of reference.

I am not about to debate whether the equations of special relativity work - they clearly do. They allow to to translate motion from the point of view of different observers. The maths works. It means you can use the laws of physics in whatever isolated frame you like.

But just because you don't need any absolute stationary frame of reference for your calculations, how does special relativity rule out its existence? I am not looking for ether. But perhaps there is a point in space where time runs fastest - no velocity or gravity effects involved (or at least negligible). Perhaps there is an absolute spacetime field that we move relative to?

The way I envision it time travels at the speed of light, so when you start moving close to that speed, time has to slow down for you. It does this because it is no longer passing by you at the speed of light. Could this be true?

Since light always travels at C (in a vacuum), doesn't that make it possible to find your absolute velocity (relative to the fabric of spacetime) by measuring the time light takes travel a set distance (in your frame) in one direction versus another (say forward versus back)?

For example in The Michelson-Morley Experiment - if they were able to measure the time taken for light to travel one way from A to B at it's constant velocity, would they have seen a difference in the time taken from B to A, given that earth is not stationary and B may be moving towards or away from starting point A - thereby making the absolute distance travelled by the light change? Obviously since they measured in both directions, this difference would cancel out.

I can buy the time and length distortion. What I don't get is just because you CAN calculate relatively - how does that rule out that you HAVE an absolute position in our physical universe?

Then again perhaps there is no such thing as constant velocity, since at every place in the universe there is AN acceleration?

And just for the hell of it - here's another one...

If someone is moving at the speed of light relative to me. They will see me as moving at the speed of light in the opposite direction. In reality one of us may be stationary - though special relativity suggests you can't know which one - in this case which one of us has infinite mass? Is the mass increase relative? Or is it absolute? Which of us experiences time stop?

Is the increase in relativistic mass merely an expression of the reduced time that one is able to exert a force when moving at relativistic speeds? IE is it not simply that time is reduced that makes an object act as if it were massive?

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# Absolute position in spacetime?

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