At https://www.eurekalert.org/pub_releases/2018-09/uop-sr091418.php … propelling spaceships without fuel. Mike McCulloch of Plymouth University first came up with the idea of quantised inertia (QI) in 2007. This involves light being converted into thrust. QI predicts that objects can be pushed by differences in the intensity of Unruh radiation in space. The idea is similar to a ship being pushed towards its bay because there are more waves hitting it from the sea ward side of the boat. The theory has already predicted galaxy rotation without dark mater – and the fact that if a system is accelerated enough (such as a spinning disc or light bouncing between mirrors) the Unruh waves can be influenced by a shield. Therefore, if a damper is placed above the object it should produce a new kind of upwards thrust. The new thruster would only require some electrictiy to accelerate the core of the thruster.