In his study "The Physics of Vibrations and Waves", H.J Pain from the Department of Physics at The Imperial College of Science and Technology in London describes the effects of mass and inductance coupling and how the vibrations are affected by the coupling. In our terms that translates to how the vibration of the string is affected by coupling it to the rest of the bass.
Another good source for understanding string vibration characteristics in coupled and non-coupled systems can be found here:
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Neither of these is an easy read, they do describe in scientific terms the effect of the substrate on the vibrating string. But I know that there will be a number of people who will not accept these findings because the test equipment wasn't an electric bass. Perhaps some scientist will re-invent the wheel by repeating these tests with a Fender Jazz. I rather doubt it though.