Are relativistic effects physically real or just apparent due to limited speed of information? Does metal rod really contract in length or do we just "see" it that way due to limited speed of light?
Explain how do you reconcile the concept of physical reality with symmetry principle in special relativity?
Yes, an observer will deduce in his frame that the length of a moving rod (which has a length l in the rest frame of the rod) has shortened by a factor of 1/gamma (gamma=Lorentz factor). So in his frame it has a length 1/gamma.
This does not necessarily mean he sees it like that, arising from the practicalities of how we see objects moving at the speed of light (eg light emitted from further away takes longer to reach eyes, so a moving perpendicular line will appear curved). This is not an effect arising from relativity though.
