@Sir Neuron,
Sir Neuron wrote: So Lorenz formula suggest anything travelling at or near the speed of light contracts in length for a particular frame of reference.
The effects are appreciable near light speed, but technically a passing train is shorter when veiwed from a platform then when it is stationary at the same platform.
Sir Neuron wrote: How about light itself?
For a particular frame of reference, doesn't light also contracts?
I am somewhat perplexed by your question. I am unsure if the concept of length can be attributed to a photon. A measuring rod can not be placed next to a photon as to do so would require the measuring rod to be travelling at the speed of light, which is a violation to special relativity. If a photons wavelength is to be considered as its length, then this observable change in wavelength is known as relativistic doppler shift, which is a different mechanism, is described by a different set of equations and does not yeild the same result as described by length contraction equations.
Anyone else?
Sir Neuron wrote:Or - From an observer travelling at or near the speed of light, doesn't everthing else, that is not, appears to the observer to contract.?
What does this mean?
If you travelled at near the speed of light from the earth to the sun, the actual distance between the earth and the sun contracts, from your point of veiw. This length contraction of the distance between the earth and the sun contributes to the twin paradox.
What does it mean? It means that distance is not absolute eg the distance between the earth and the sun as meausred from a stationary position relative to the earth and sun is different, but no means more wrong or correct, than measured while you are in motion relative to the earth and sun.