Physics already knows that the quantum vacuum can be damped (reduced in one area) by metal conductors. This is the well-known Casimir effect. It is now also well accepted that the quantum vacuum can be enhanced from the point of view of a high acceleration system. This is known as Unruh radiation. Quantised inertia then predicts that if such a system is made, such as a laser fired into a reflecting cavity, and the cavity is made asymmetric then the energised quantum vacuum will be damped more at the narrow end than the wide end and the cavity will be pushed towards its narrow end. It will move without having to expel propellant. In this way quantised inertia predicts the behaviour of the emdrive (see references). Quantised inertia implies that this is what nature has been doing since the dawn of time with inertia, where the quantum vacuum is damped by a relativistic horizons caused by acceleration, pushing objects back against that acceleration. This part of the theory is well backed by astronomical data - it predicts galaxy rotation without dark matter. It is an obvious next step to replace the horizon with a metal plate and make the old inertial process controllable.
So, what's new in this paper? Well, it turns out that you don't need the laser in the cavity or any energy input, if the cavity is small enough (about 129 nm). Then the zero point field itself is made inhomogeneous by the cavity's asymmetry and is strong enough to push the cavity, which is pretty light. Build a array of these nano-cavities and it should push itself, in the same way a boulder will roll down a hill. The hill in this case is the quantum vacuum, so the boulder may in fact be able to roll up a physical hill by 'rolling down' the one in the quantum vacuum. The applications are new launch systems and a way to get to the nearest stars in a human lifetime. A craft with propellant-less propulsion makes such a trip possible within a few years. A bold prediction indeed, but at least it is testable.
All that is needed is some way to build such a nano-cavity or an array of them, and then weigh it. Does anyone out there have a lab with photo-lithography or another technique that can build up a 3d matrix of nano-scale asymmetric metal cavities? If so, please email me and we can apply for funding to test the principle. The downside of failure would be some embarrassment for me, a small price to pay. The upside would be a space-based civilisation in our lifetimes & interstellar travel.
By the way, I have started publishing my sci-fi novel titled 'One Step to Tau Ceti' on patreon. It explains part of the philosophy behind quantised inertia in a, hopefully, amusing and entertaining way: https://www.patreon.com/OneSteptoTauCeti
McCulloch, M.E., 2020. Can nano-materials push off the vacuum? Progress in Physics, Vol 16, 2. http://www.ptep-online.com/2020/PP-60-02.PDF
McCulloch, M.E., 2017. Testing quantised inertia on emdrives with dielectrics. EPL, 118, 34003.