Say I have an ideal (long and tightly wound) solenoid, and I put a ring of wire around it (large ring). Then, by Faraday's law, if I put a current through the solenoid there will be an induced current in the wire ring around the solenoid. But if there are no B-field lines crossing my ring of wire, how can this happen? Usually when you apply Faraday's law, its equivalent to using Lorrentz force law on each infinitesimal piece of wire (which contains free charges) and it turns out to be the same as the change in flux, by Stoke's theorem. It's just weird that the loop of wire "sees" zero change (if the solenoid is ideal, there are no field lines outside it), so then how can there be an induced current? How does the information about the current in the solenoid travel from the solenoid to the wire loop? If there is zero field outside the solenoid, what carries this information? Can someone explain this?