(Not sure if this should go in SR/GR forum) I watched a Susskind lecture last week in which he was discussing the fundamental law of charge conservation. He used the example of an electrostatic field surrounding a point charge, and stated that, were we able to suddenly make the charge disappear, we could send information instantly b/c the field propagates instantly. I think I must have misunderstood him. I understand disturbances in the field (photons/EM waves) travel at c, but is it a settled matter that the field itself propagates instantly???