Is light conducted by space, or does it travel through it?
Light has nothing to do with space. It is a property of the electromagnetic field when this field is undergoing changes. from its point of origin, this field radiates out into space in all directions. It is invisible, but can be felt by charged particles. When this field is changed, for instance by suddenly altering the position of its emitter, a kink develops in the field which propagates out into space at the speed of light. Under the right circumstances of acceleration, this kink becomes electromagnetic radiation - light. So space simply acts as a passive container for the electromagnetic field, which in turn is the 'medium' in which light exists.
If there is no electromagnetic field in space, there is no light either, as in the inside of a closed, shielded box. The maximum propagation speed is the speed of the expansion of the electromagnetic field in a perfect vacuum, which is 299,792.5 kilometers/sec.
Copyright 1997 Dr. Sten Odenwald
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