electromagnetic drive (EmDrive)

The electromagnetic drive (EmDrive) is a proposed spacecraft propulsion system that claims to generate thrust without fuel or propellant. It uses microwaves confined within a specially shaped, closed resonant cavity. According to its proponents, the microwaves interact with the cavity's design to produce a tiny but continuous push in one direction—an effect not yet fully validated by mainstream science. If proven effective, the EmDrive could enable more efficient space travel, but its mechanism challenging current physics principles remains controversial and unconfirmed by rigorous experimental evidence.