As tdracer says, not beyond the scope of physics, nor entirely new, since it combines aspects of previous propulsion systems.
1) creating a "containment" with oblique (slanted /\ ) super(or hyper)sonic
shockwaves in air. Concorde (and indeed any supersonic turbojet) does this one way or another. Build the "shape" of the engine inlet out of air compressed by the passage of the vehicle at speeds faster than air itself can get out of the way, and the ramming of the air into the inlet. Use that as a pre-compressor, to feed compressed sub-Mach air into (and around) the turbine engine.
2) Fuel-air detonation - used in fuel-air bombs. Get a nice balanced mixture of fuel dispersed in air, and then set it off. BOOM!
3) keep the detonation going by spinning it around the centerline of the engine - rather like a Catherine Wheel that is a cone (oblique < ) rather than a disc (flat |) - so that the thrust output aims mostly backwards rather than sideways. As the detonation front circles around in the engine, it keeps encountering fresh fuel/air mixture, from a continuous intake, to detonate. Not perpetual motion, since we do need to keep adding fuel and air, but continuous detonation. Boo-ooo-ooo.....ooo-ooo-ooo.......m!
But probably darned hard to control, especially using mostly "hard air" to sculpt the movement and detonation region.
Two obvious problems (at least) that will need to be solved to make it a reality.
1) the problem with all hypersonic ram engines - how to get it up to hypersonic speed in the first place, so that it can do its thing.
2) Maintaining adequate stability in the shockwaves that shape the
virtual detonation chamber. Since those are basically just highly-compressed air-curtains, they can go unstable. Resulting in an event innocuously called an "engine unstart," but which in reality is the Mother of All Compressor Stalls, or a massive back-fire. BOOM! Usually destroys the engine, but aircraft
have landed safely after an unstart (I think). But up until now they have only occurred at mere supersonic speeds (Mach 2-3 or so) - not sure what would happen with a hypersonic unstart.
Back in 1946-47, Stanislaw Ulam (he of the Teller-Ulam H-Bomb design) proposed what became - briefly -
Project Orion. A spacecraft that propelled itself by dropping nuclear bombs out of its arse and riding
their detonation shockwaves. It was the ultimate hard-arse - with a couple of thick sprung steel pusher-plates on the back, to absorb the nuclear blasts while transmitting the force/thrust to the payload.
Didn't get much past the sketchbook stage, although they successfully tested the concept with conventional explosives.
This may meet the same end. And then again.....