EmDrive

Common card · No. 378881

The EmDrive is a controversial device first proposed in 2001, purported by its inventors to be a reactionless drive. While no mechanism for operation was proposed, claims about the EmDrive appear to violate the law of conservation of momentum and other laws of physics. The concept has at times been referred to as a resonant cavity thruster. Physicists and engineers generally regard the EmDrive concept as pseudoscience. Neither person who claims to have invented the EmDrive committed to details about the device beyond showing prototypes they have built. While the lack of a published design or mechanism makes it hard to say whether a given object is an example of an EmDrive, over the years prototypes based on its public descriptions have been constructed and tested but results have been mixed to negative and often minor or attributed to errors. In 2016, Harold White's group at NASA observed a small apparent thrust from one such test, however subsequent studies suggested this thrust was a...

Read on Wikipedia · Image David A. Brady, Harold G. White, Paul March, James T. Lawrence, and Frank J. Davies. Eagleworks Laboratories, NASA Lyndon B. Johnson Space Center, Public domain