In 2001, British engineer Roger Shawyer introduced the concept of an EMdrive, a propellant-free thruster that would completely revolutionize the field of transportation. Several years down the line, the “reactionless drive” still remains a dream pursued by the U.S. and Chinese militaries. It would provide an incredible advantage to whoever develops it first.
“Also known as a radio frequency resonant cavity thruster, an EMDrive supposedly generates thrust without the need for a propellant. It’s an electromagnetic thrust produced by bouncing microwaves inside a cavity — like a person sitting inside a box and pushing from the inside to make it move. Plus, the total momentum generated by the EMDrive supposedly increases as it moves,” according to NowScience.
An EMDrive essentially promises “free energy,” something that almost all scientists know is impossible according to existing knowledge. The very idea that an EMDrive will produce an action without generating an opposite reaction violates one of the fundamental rules of physics. Despite looking impossible, several research teams have studied the possibility of such a technology.
In 2016, a group from NASA claimed that they had built a prototype device that generated thrust without any reaction to balance it. However, a subsequent study by a research group from Germany proposed that the observed thrust was simply the result of the magnetic fields produced by the electrical wires that were feeding the EMDrive.
The EMDrive, if created, would have major military implications. The country that invents it will easily take a leadership role in space exploration and weapons development. The U.S. Defense Advanced Research Projects Agency (DARPA) is funding more research into the area even though some have criticized the agency for “wasting money on impossible science.”
What makes DARPA desperate to gain access to the EMDrive technology is the fact that the Chinese are also said to be heavily invested in the tech. Though various Chinese outlets have reported that their scientists have succeeded in creating a prototype of an EMDrive, such claims have often turned out to be false.
“The DARPA mission is to embrace and advance transformational change in the U.S. military, but… we must strive to beat the other guy to the punch line and ensure there will never again be another Sputnik moment… If DARPA does not gather this evidence and publish the results, positive or negative, then who in the U.S. government will?” Jess Sponable, a former program manager at DARPA, said to Popular Mechanics.
In October 2018, DARPA gave a US$1.3 million grant to British physicist Mike McCulloch for further research into the subject. “He’s published over 20 papers on his QI [Quantized Inertia] theory, which is also known as Modified inertia by a Hubble-scale Casimir effect (MiHsC). McCulloch’s is a radical theory with wide-ranging implications that affect everything from the galactic rotation to Dark Energy,” according to Business Times.
McCulloch will reportedly be using light to validate his QI theory rather than the microwaves that powered the original EMDrive. While one experiment will use a laser bouncing off asymmetrical mirrors, another will use light to travel in a loop. If McCulloch’s experiments turn out to be successful, space craft could soon sport sleek and highly efficient EMDrives rather than huge, inefficient rocket boosters.