Rapid Spacetime Transport and Machian Mass Fluctuations: Theory and Experiment

The equations of physics, generally, are invariant under the symmetry groups of infinitesimal space and time translations. This means that energy and momentum are conserved in “isolated” systems, that is, systems that do not couple physically to anything outside of themselves. Among the propellantless propulsion schemes of interest in the context of “breakthrough propulsion physics”, however, are several apparatuses that purport to manipulate electromagnetic fields in ways intended to achieve propulsion by generating a force in one part of a system that is allegedly not cancelled by an equal and opposite force elsewhere in the system. (As one example of this sort of scheme, see Corum, et al., 1999.) The unbalanced force, then, is the source of an acceleration of the system, achieved without acting on anything outside of the system. Setting aside schemes involving beamed electromagnetic radiation (so-called “photon rockets”), evidently conservation principles and their observationally corroborated underlying symmetries simply forbid such behavior. They dictate that the acceleration of a spacecraft can only be achieved if it couples somehow to the rest of the universe, with respect to which it moves. (In the case of normal rockets, this coupling to the rest of the universe is accomplished through the inertia of the propellant exhausted, for it is the gravitational action due to cosmic matter on the propellant that causes its inertial properties, making it possible to “push off” of it.) Since direct electromagnetic coupling to exterior matter does not take place in these allegedly unbalanced force systems, if an accelerating force on the system is to be actually generated, it must involve the gravitational/inertial interaction – the only long-range force (other than electromagnetism) that couples local objects to distant matter. I say gravitational/inertial interaction here because in relativistically invariant, non-linear theories of gravity, in particular, in general relativity theory (GRT), inertial reaction forces are a consequence of the gravitational action of chiefly the most distant matter in the universe (Woodward and Mahood, 1999; Woodward, 2001). This fact, first argued with clarity and force by Sciama (1953 and 1964) as the essence of Mach’s principle, has only lately been fully appreciated. Allowing the foregoing, it appears that “breakthrough” propulsion can only be implemented in one of two ways. The first is to find a way to “convert” electromagnetic fields directly into gravitational/inertial fields; fields with the requisite strength – enormous by comparison with the gravitational fields normally associated with objects smaller than small planets – to accomplish some desired rate of acceleration. But there is no credible evidence that localized electromagnetic fields can be directly converted into strong gravitational fields that couple to distant matter. Electromagnetic fields couple to, and have as their sources, electric charge, not mass. Gravitational fields, on the other hand, have mass-energy as their source, not electric charge (and its currents) per se. The energy in electromagnetic fields is a source of gravity. But the energies needed to produce strong gravitational fields are gargantuan, and the fields produced by large concentrations of mass-energy are neither “beamed” nor directed, as one would want for propulsive purposes. The second way electromagnetic effects might be manipulated to achieve propellantless propulsion is to find a way to drive large changes in the instantaneous value of the local mass-energy content of spacetime. This does not directly produce beamed gravitational effects. But it does permit one to extract stationary forces that may be used for propulsion that involve gravitational/inertial energy and momentum fluxes coupling the local system with distant matter, as I sketch here now. As such, this seems to be the only way to achieve propellantless propulsion without prima facie violations of established conservation principles.