NASA validates the “impossible thruster”?

NASA validates the “impossible thruster”?  A “thruster” is an engine that will cause a spacecraft to move.  Several readers sent me links to this story, which I've been following since the Chinese “confirmation” last year.

The claim of the designers of this thruster is extraordinary: that their thruster works without any reaction mass at all.  It requires nothing but electricity to work.  Every other thruster works by throwing something (anything!) away from it at high speed.  Newton's third law says that every action causes a reaction – and all these other thrusters depend on that.  It's the only way anyone has ever made a thruster that works.

Furthermore, an extremely well-tested physics principle – the conservation of momentum – requires that any change in momentum (as in a thruster accelerating something) must be accompanied by a precisely matching counter-change (as in the momentum of the quickly receding mass being thrown away from the rocket).  A thruster that didn't throw away any mass would violate this principle, and nobody has ever before found a violation.  You could justly call the conservation of momentum a bedrock physics principle.  To find a violation of it would upset darned near everything we thought we knew about physics.

So...

I am very skeptical of this claim, despite the NASA “validation”.  I put that word in quotes, because I note that the NASA engineers called the effect they detected an “anomalous thrust”, which I think is exactly right: it's a thrust whose source they have not yet identified.  This thrust is incredibly tiny, too – just the sort of thing you might get from an instrumentation problem, an experimental error, or even measurement error.  I infer from their wording that the NASA experimenters are themselves unconvinced – and it's easy to see why.  To a physicist (even of the amateur flavor!), this claim is about as likely as claiming that you could fill your gas tank with water, then add a tiny tablet, made from dried yak dung fermented in sloth urine, to create high-octane gasoline.  It's just too good to be true...

I say this very reluctantly, though.  If it were true somehow, then all sorts of marvelous things might derive from it: interstellar travel, flying cars, backpacks that took a load off your feet, etc.  I'd love for those things to magically become possible!

But I'm not betting on it :)