Reason for repulsion force between two north or south poles?

Question

reason for repulsion force between two north or south poles

Answer 1

I wanted to write some soppy answer, but started to think. I wonder if scientist truely know what exactly a magnetic field is. Same with gravity, how can two objects from across the galaxy have a force on each other with no medium through which that force can be exerted? Also, lets say you place in an instance an object (make it a star) 1 light year away from you. Will its gravitational force have an immediate effect on you, or do you think it will take some time.