Ever since the EM drive was first reported in the news, arguments have raged in the scientific community over whether it should work or not. The idea of a device that uses microwaves to create thrust and not propellant, thus violating Newton’s Third Law of Motion, has been controversial, to say the least. However, tests of the device, notably at NASA’s Eagleworks lab at the Johnson Spaceflight Center south of Houston, has shown that it produces thrust. The trust could have been the result of experimental error. Now, according to Science Alert, a possible explanation has been proposed that would explain why the Em Drive produces thrust without violating Physical Laws.

An alternate theory of quantum mechanics

A couple of researchers at the Center for Philosophy of Sciences at the University of Lisbon, José Croca and Paulo Castro, have just published a paper that suggests that the pilot wave theory of quantum mechanics explain how the EM drive works. The paper also points the way to getting stronger thrust from the EM drive. The problem is that pilot wave theory is itself controversial.

Most scientists subscribe to the idea that particles do not have an actual location until they are observed. Pilot wave theory, on the other hand, posits that particles have a precise position at all times. The theory states that when an object emits a wave, it is pulled to the part that has the highest energy density, hence the term pilot theory.

The way that pilot wave theory works for an EM drive is that because the device has an asymmetrical cone or frustum the microwave field it generates is asymmetrical as well, with a region that has a higher energy intensity. The device is then pulled toward the area of higher energy intensity, creating apparent thrust. Moreover, by altering the shape of the EM drive, the area of higher energy intensity could be increased, thus creating more thrust.

What happens next?

The research, published in “The Journal of Applied Physical Science International”, is just a theory and has not been tested in a real-world experiment. Croca and Castro are currently considering building their own EM drive setup to start measuring and proving their theory. In the meantime, other organizations, such as Eagleworks, could take the Portuguese research into account in refining their own experiments.

The EM drive has caused excitement among space advocates. The technology has even been featured in a prime time science fiction show, popularizing it for the general public. It the EM drive can be proven to work at scale, travel to Mars, for example, could take weeks instead of months, opening up the solar system to exploration on a scale never before imagined.