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stevmg
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drudkh said:i understand the michelson–morley experiment and its result; but what i don't know yet is the reason.
Example:
A torch in free space is moving at a velocity [v] w.r.t me. Considering the material nature of light, shouldn't the speed of photons emitted from the torch be [v+c] w.r.t me?
According to the experiment, it's not so.
I know how relativistic velocities are formulated (lorentz transformation, einstein's addition, etc.). But all these calculations are based on the accepted norm that light speed in invariant. Why? What's the scientific explanation of this (if any)? Is it still a mystery?
I've seen other posts regarding the speed of light, but couldn't go through them all. So, apologies if this topic already exists.
stevmg said:To elucidate on this point in particular, the invariance of the speed of light in his situation is taken up by time dilation and length contraction. They do work opposite to each other but one offsets the other. What should be an increase in closure speed as you posit is enhanced by the length contraction yet offset by the time dilation so that, relative to you, things "slow down" back to light speed.
stevmg
Using drudkh's example cited above and using Einstein's velocity addition formula, closure speed between a particle moving to the right at v and light coming from the right and moving left at c would still be c.
Why? Let's use v as the velocity of the particle expressed as a fraction of c and therefore c = 1
closure velocity = (c + v)/(1 + vc/c2) = (1 + v)/1 + v) = 1
If, instead of a particle moving to right at v, we substitute a photon or a light wave moving at c or 1 and still light comes to the left at c or 1, the formula becomes:
closure velocity = (1 + 1)/(1 + 1) = 1
Ain't life grand? The max speed attainable is 1 or c.
Can we ever have a closure velocity > c? Not according to the above.
Someone show me and drudkh wrong!
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