Among the four forces of nature, only electromagnetic force has opposite interaction. that mean's it can attract and repel. Gravity force has no such behaviour.

Gravity is not a force per se. it's a deformation of space by huge mass. It's like if you put a cannonball in the middle of the matress. The cannonball will deform the otherwise flat surface of the matress. if you put a golf ball on the surface of the matress near the place where you put the cannonball, the deformation in the surface of the matress will cause the golf ball to roll into the cannonball. This is how large body in space attract another mass into it. because ths masses simply rolling into each other along the spacetime curvature. Now theoretically, it's possible to create anti-gravity. But we have to deform the surface of the matress upward instead of downward so the golf ball will roll outward instead. It implies that the cannonball must have a negative mass. Now how do we create negative mass? can you imagine the -5kg cannonball?

The anti-gravity peoples simply treat Gravity as a foirce just like magnetism. This is where they mistaken.

This post has been edited by MrUbikeledek: Apr 2 2012, 08:00 AM

Weight into speed? Sound's like gravity assisted acceleration and we have it already. Magnetic principle only work on charged objects.