As we know from movies such as "Star Wars" and "Star Trek", the characters move as if they were on a planet. The question is - could there be a mimic to gravity on the spaceship? Obviously, we cannot put too much mass on a spaceship, which would make the spaceship much more inert to acceleration/deceleration. So the obvious other force is the electromagnetic force. One could envision a very strong negative field on the bottom of the field, and people wearing positively charged packs that did not mix in with the surrounding areas. We can confine charges within magnetic fields. The gravitational field and the electromagnetic field both decrease as the square of distance, so the geometries of the two fields aren't likely to be different. So the question is, is such a system possible?