Star Army ships "defeat" the conservation of momentum through use of complex asymmetric [peristaltic] electromagnetic/electrostatic/gravitic fields (which function as combined propulsion, defense, and manuevering systems). Momentum (as viewed from an outside observer) is absorbed and redirected by the shields, while the ship technically stays still (relatively) within the pocket of space enclosed by the fields. No acceleration is felt to the ship, although the ship can stop on a dime, literally. The law of conservation cannot be truly defeated and therefore must be avoided through the use of exotic matter/energy and such. The law of conservation of energy cannot be truly defeated but potentially limitless energy can be siphoned off of aether.