Are we ever going to understand what makes matter resist acceleration? If we can get a handle on inertia, we’ll have a better idea what’s possible when it comes to exotic propulsion. 19th Century physicist Ernst Mach believed that inertia was the result of matter being acted upon by all other objects in the universe, even the most distant ones. At the University of California at Fullerton, James Woodward has been studying inertia in a Machian context for some time, and an implication that appears to grow out of it: an object undergoing acceleration may experience transient fluctuations in its mass.
It will take a great deal of experimentation to find out whether there is anything to this, but the idea is interesting enough to keep Woodward working. His theories are put to the test in the laboratory, for they predict an effect that should be measurable. Indeed, his work with capacitors produces results that can be interpreted as mass reduction, though getting a clear data signal through the experimental noise is not easily done. How such mass reduction squares with the laws of physics, and just how far it can be taken — is this a clue to possible anti-gravity effects? — are questions that remain unanswered.
But the implications are intriguing. Be aware, then, of two sites that focus exclusively on Woodward’s activities. The polymath (he’s a member of both the history and physics faculty at Fullerton) maintains a research page of his own with links to older papers explaining his theories, and a bibliography of recent publications. A PDF on propellantless propulsion is useful, as is the older paper “Mach’s Principle and Impulse Engines: Toward a Viable Physics of Star Trek?” which Woodward presented at NASA’s Breakthrough Propulsion Physics workshop in 1997.
Woodward doesn’t refer to what he’s studying as the ‘Woodward Effect,’ but the name has begun to settle in, and Peter Vandeventer maintains a Woodward Effect site containing background papers (unpublished) and links to further information. As Vandeventer notes, Woodward prefers to talk about the ‘Mach Effect,’ a refreshing dose of humility in a world filled with people intent on naming things after themselves. Whatever we call it, the effect studied by Woodward and others gives some credence to the notion of a ‘Mach-Lorentz thruster,’ a spacecraft that, as Woodward once said, “…puts out thrust without blowing stuff out the tailpipe.”
Be aware, too, of a recent paper by Martin Tajmar, Florin Plesescu and team that discusses work sponsored by both the US Air Force and the European Space Agency. The authors attempted to “…measure the gravitational field induced by a non-stationary gravitomagnetic field generated by an angularly accelerated superconducting ring.” If confirmed, these findings would appear to demonstrate the production of a gravitomagnetic field of measurable magnitude in the laboratory. Which is to say that years of research lie ahead to examine such effects and place them in a sound mathematical context.
We may find, of course, that there are other explanations for the results of both Woodward’s and Tajmar’s experiments — Tajmar, for example, notes quite different results from earlier claims by Evgeny Podkletnov about gravitational shielding effects above rotating superconductors. But provocative work that tests the boundaries of known physics is worth keeping an eye on as followup investigations continue. Most hypotheses fail — this is how science works — and we are early on in putting a number of fascinating concepts to the test. Let’s hope funding for the most testable of these ideas continues to emerge as we get an idea of which hypotheses make sense.