Inertia is the tendency of objects in motion to keep on moving in the same direction, and of a body at rest to remain on the sofa. When you are standing on a bus which starts with a jerk or stops suddenly, inertia is the force that throws you onto the floor.

Then there are the g-forces contorting faces of people in an accelerating rocket. Gravity and inertia must be overcome somehow if spacecraft are to perform tricks attributed to supposedly extraterrestrial objects in the sky. Viewers, including airline pilots, have described unidentified craft which make sudden sharp turns without reducing speed, or which accelerate from hovering to high speed. For occupants of a spacecraft to survive the sudden changes of location, inertia would have to be canceled or manipulated in and around the object. This would be in effect a controllable gravity field. The possibility of inertialess drive is nearer to us, because mainstream scientists now have a picture of what might be the cause of inertia.

A few years ago the respected physics journal, Physical Review, published a paper by B. Haisch, A. Rueda and H.E. Puthoff, with a theory about inertia. They point to the fact that what is popularly known as empty space is not empty; throughout the universe it is seething with zero-point quantum fluctuations of electromagnetic energy. The three physicists suggest that interaction with this zero-point field causes both inertia and gravity.

If we understand that interaction, can we go to the stars? Maybe understanding it is a first step. More recently, one of those three physicists, Dr. Hal Puthoff, elaborated. In the science magazine Ad Astra, he writes about the vacuum of space as an energy reservoir, with energy densities as powerful as nuclear energy or greater. If the zero-point field (ZPF) could be mined for practical use, it would, everywhere in all galaxies, supply energy for space propulsion.

How would it work? Puthoff gives clues, such as a phenomena called the Casimir Effect which pulls closely spaced smooth metal plates together. Another researcher, Robert Forward, has demonstrated how electrical energy could be taken from the electromagnetic fluctuations of the vacuum by manipulating this effect. Puthoff also cites a paper by his co-authors, Haisch of Lockheed and Rueda of California State University, along with Dr. Daniel Cole of IBM. They propose that the vast reaches of outer space constitute an ideal environment for ZPF acceleration of nuclei and thus provide a mechanism for powering up cosmic rays. He mentions a report published by the U.S. Air Force about the possibility of using a sub-cosmic ray approach to accelerate protons in a cryogenically cooled, collision-free vacuum trap and thus extract energy from the vacuum fluctuations...

What it boils down to, Puthoff says, is that scientific experiments indicate that human technology can alter vacuum fluctuations. This leads to the related idea that, in principle, we could also change gravitational and inertial masses.

Puthoff points out that accepted theories up until now only looked at the effects of gravity and inertia, instead of at the origins of these fundamental forces. He notes that the first scientist to hint that gravity and inertia might be rooted in the underlying vacuum fluctuations was the Russian dissident Andrei Sakharov, in a 1967 study.

Concluding his Ad Astra article with a quote from science fiction author Arthur C. Clarke saying that highly advanced technology is indistinguishable from magic, Puthoff adds that fortunately such magic appears to be waiting in the wings of our deepening understanding of the quantum universe in which we live....