Hey there! I was just listening to Richard Feynman on the way home and hit yet another issue I have with relativity... I'd be most thankful for any input! :) So, suppose we got two charged particles moving parallel to each other. A charged particle has an electrical field - if it's moving, this field changes, which in turn leads to a magnetic field. Having both particles move parallel to each other we get a force between them - they'll move towards each other. Now... let's sit on one of those particles. Relativity says that there will be no magnetic field then because, from our point of view in time and space, they are not moving. So what now - are they moving towards each other, or not? The only answer that I could think of is this: they are both standing still and moving towards each other at the same time... depending on where you are as observer? Is this the concept behind time/space dilation or contraction? Thanks for your time!