There’s an interesting pair of articles that might interest you. In the first from Wired David Hambling reports on an apparently successful test by NASA of an impossible space drive:
The Nasa team based at the Johnson Space Centre gave its paper the title “Anomalous Thrust Production from an RF [radio frequency] Test Device Measured on a Low-Thrust Torsion Pendulum”. The five researchers spent six days setting up test equipment followed by two days of experiments with various configurations. These tests included using a “null drive” similar to the live version but modified so it would not work, and using a device which would produce the same load on the apparatus to establish whether the effect might be produced by some effect unrelated to the actual drive. They also turned the drive around the other way to check whether that had any effect.
Back in the 90s, Nasa tested what was claimed to be an antigravity device based on spinning superconducting discs. That was reported to give good test results, until researchers realised that interference from the device was affecting their measuring instruments. They have probably learned a lot since then.
The torsion balance they used to test the thrust was sensitive enough to detect a thrust of less than ten micronewtons, but the drive actually produced 30 to 50 micronewtons — less than a thousandth of the Chinese results, but emphatically a positive result, in spite of the law of conservation of momentum:
“Test results indicate that the RF resonant cavity thruster design, which is unique as an electric propulsion device, is producing a force that is not attributable to any classical electromagnetic phenomenon and therefore is potentially demonstrating an interaction with the quantum vacuum virtual plasma.”
Not so fast says Steven Novella of NeuroLogica:
The bottom line is that I just don’t believe it. I could be wrong. I hope I’m wrong. I don’t necessarily think the results of NASA’s test are untrue, just that I don’t think they have “validated” that the propellantless drive is what proponents say it is.
My reaction is identical to the claim made in 2011 that a team of researchers found that neutrinos travel faster than light. I didn’t believe those results either. The researchers were very careful, they rigorously reviewed every aspect of their experiment, and only announced the results when they were confident they ruled out all error. The physics community didn’t believe it, but they did their due diligence. After further analysis, it was found that the results were an error – an artifact introduced in the experimental setup. Initial skepticism was vindicated.
The claims made for a machine that can provide thrust without propellant is as unlikely and at variance with the laws of physics as neutrinos traveling faster than light or free energy machines. Sure, it’s always possible that our understanding of the universe is incomplete in a way that allows for one of these phenomena to be true, but our current understanding calls for extreme initial skepticism. Such a stance has a very good history to support it.
I find the whole thing a very fun idea. If it’s true and this impossible drive actually works, not only will it revolutionize satellite and space station design, it could have a major impact on deep space exploration with ripples into our basic understanding of the universe. If it isn’t true and it doesn’t work, it will certainly impel some re-thinking of how we go about designing experiments.