This article is from 1991 (I think) but just re-published and explains some scientific reasons why cables can sound differently. A good read for anyone interested or anyone who thinks audio need more science.
Those are interconnect cables, which are entirely different than speaker wire.
And yes, I certainly do agree there are scientific reasons why cables can sound different. Doesn't mean they do or will though. Pitting the scientific reasons against a blind test to determine if the listener actually does discern a sonic difference is also entirely different.