So this paper's foundation seems to be the idea that 2 photons can propagate in the same direction with the same wavelength and phase exactly 180 degrees off. A

So this paper's foundation seems to be the idea that 2 photons can propagate in the same direction with the same wavelength and phase exactly 180 degrees off. As such, the net effect on the EM field would be 0, so they wouldn't interact with anything through the EM force and could pass through the walls of the chamber, escaping the device and acting as propellant. Importantly, the photon pair, they say, still caries energy even though it doesn't interact with anything. My question for anyone with a background in this is, is this bunk? It doesn't square with my intuition. Suppose we have two plane waves in the EM field propagating like these photons, exactly out of phase, how would this be different from no plane waves in a completely empty space? Where's the energy in this photon pair scenario? If it doesn't interact with anything, in what sense could it possibly have energy? Moreover, what would the production of a pair look like? They're claim of it having energy is important only in so far as it is a release of momentum for the drive, so the formation is the key part. Suppose there's just the first photon - is emitting the second of the pair equivalent to just absorbing the first one? In which case, their claims that photons don't just "vanish for nothing" aren't valid. Edit: Oh and that stuff about Gauss Bonnet ("Geometry at any point along an action can be recapped by signed curvature.") - I do research in related areas of math and could recite Gauss-Bonnet without reference, but I have no idea what they're trying to say. Gauss-Bonnet is a statement relating the global topology of a surface to its curvature, what surface would they even be considering here and how would its topology matter? Honest question: is this representative of how physics papers are written in terms of style? Sentences like "It is no new idea that inertial effects are immediate, because the vacuum resists changes by embracing everything" make me wonder how physicists communicate.