Spacecraft and satellites could in future be launched into space without the need for fuel, thanks to a revolutionary new theory.

Dr Mike McCulloch, from the University of Plymouth, first put forward the idea of quantised inertia (QI) – through which he believes light can be converted into thrust – in 2007.

He has now received $1.3million from the United States Defense Advanced Research Projects Agency (DARPA) for a four-year study which aims to make the concept a reality.

The QI theory predicts that objects can be pushed by differences in the intensity of so-called Unruh radiation in space, similar to the way in which a ship can be pushed towards a dock because there are more waves hitting it from the seaward side.

The theory has already predicted galaxy rotation without dark matter, and the fact that if a system is accelerated enough – such as a spinning disc or light bouncing between mirrors – the Unruh waves it sees can be influenced by a shield. Therefore, if a damper is placed above the object, it should produce a new kind of upwards thrust.

Chemical rockets are very expensive because of the explosive propellant they need, so this new kind of thruster would be much cheaper and safer as it would only need a source of electrical power to accelerate the core of a thruster.

