Is light conducted by space, or does it travel through it?

Light is not conducted through space the way that heat is conducted through a solid. Light 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.

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