Maybe I'm being pedantic but what I read seemed to be saying it wasn't antigravity at all. It was bending gravity to go the opposite way through a toroidal shape.
Pure semantics. Contemporary physicists bend over backwards to avoid the term "antigravity."
If you have a gravitational dipole generator on the table and objects placed above it float to the ceiling, then it doesn't really matter how you describe it; for all practical purposes, it's antigravity. The language of general relativity is particularly unhelpful in cases like this. It's vastly superior to describe these effects in gravitoelectromagnetic terms, because it's perfectly qualitatively analogous to electromagnetism, and it's actually useful to the engineering to describe it that way.
In this case, the analogy corresponds to an electromagnetic inductor - Forward's device is simply a gravitomagnetic inductor. And when the current is changing through a toroidal inductor, it generates a dipole. In this case, a gravitoelectric dipole, just as an electromagnetic inductor with a changing current creates an electric dipole. For all practical, conceptual and mathematical purposes, a positive gravitoelectric pole is an ordinary positive gravitational field, and a negative gravitoelectric pole is a negative gravitational field, aka "antigravity."
It’s kinda bizarre that you seem so fixated on discrediting this idea, which you’ve never encountered before. Most of the people I share this with are excited to learn that this effect, which they’ve been told is impossible without exotic matter, isn’t. But you just seem to be annoyed about it. At present this is literally the only gleam of real hope pointing the way toward practical manned interstellar spaceflight, unless you’re willing to take some huge (and I believe unwarranted) leaps of faith to either embrace Robert Schroeder’s M-theory idea, or to postulate the existence of exotic/negative mass and it’s practical implementation.
The difference being in my mind like a lens, not a shield. Unless you're thinking of some kind of 'gravity cloak' perhaps?
Definitely none of those. A negative gravitoelectric pole would actually produce the opposite of an ordinary gravitational lens effect - diverging light paths rather than focusing them, and producing a gravitational blueshift rather than a redshift. The relevant region perfectly mimics the negative gravitational field effect of exotic matter, via matter only.
On that, I would agree. But what's your method?
I think of a "method" as something that's been experimentally, or at least theoretically, verified in the academic literature. Anything less is speculation, and I'd rather not waste anyone's time with idle speculation. So far, everything we’ve discussed is established, hard science. Let’s keep it that way.
It's actually an old idea, not mine. It's a Bracewell probe put together with a Von Neumann probe.
Bracewell probe - Wikipedia
A Bracewell probe would be something like an artificially intelligent UFO. I don't see anything about it building little greys to perform medical examinations. Maybe you should coin the idea and call it a Marduk Probe. Though I do worry about the connotations that may engender, here in the post-Communion era ;
Sure, it could be control of gravitation. As a child, I used to watch lights in the sky do exactly what you describe -- fast motion, right angle turns that sure looked non-ballistic.
But if they're solid state devices, they could also tolerate extreme g forces and not care. And that right there is parsimony. No extra actors needed that profoundly change the rules of the game as we understand it.
And should that be explored first?
Bah. Even if it were possible to execute zig-zag trajectories at thousands of miles per hour, and leap from a standstill to 8,000mph in the blink of an eye, through some other method, and without any visible or detectable reaction mass emissions of any kind including wind - we'd actually have to find some new force in nature to do that, if it's not a gravitational effect. That might be possible, like Schroeder's idea about tapping into the bulk. But I'd rather work with a force in nature that's proven, and we already understand in principle how to engineer, and which holds real promise for the development of rapid manned interstellar spaceflight without incurring insurmountable costs in energy.
Magnetoaerodynamics, which Stanton Friedman seems to advocate as an explanation for some UFOs, won't work in space (and I see no way to produce the maneuvers that I've seen in the sky, via this method). And all of the known techniques for interstellar propulsion, ranging from fusion propulsion to light sails, are wholly inadequate for a host of reasons, some of which we’ve covered. Plus, lots of very capable people are already working on all that stuff. They can have it.
Sure. It's a neat trick if it works, and you find tachionic matter, and don't blast your target with equivalent of a mini quasar's worth of redshifted radiation if you get there.
Here's the thing: if you're looking for a known, viable method of manned interstellar spaceflight propulsion that can get you to the nearest star and back without bankrupting the planetary economy several million times over and/or requiring travel times that leave all of your loved ones dead upon your return to Earth, then prepare to be disappointed, because it doesn't exist.
It has to be invented. Or perhaps re-invented: the military may have already invented it, or maybe not, but they'll never share with us – they’re entirely too concerned with the serious business of perpetrating mass murder on a daily basis, to diddle around with harebrained hippie ambitions like creating a better future for humanity.
Exactly. They appear to have conventional levels of mass, which makes all the mass-energy dense conceptions of propulsion go away. Because a large toroid capable of generating lift like you described above could be so M-A dense it would sink down to the earth's core if you shut it off.
It's possible that the field is never fully shut off, even when they land. But if any of the crash cases are real, then yes, these objects can't contain neutronium mass-energy densities or they'd either plunge straight through the planet, or vaporize a continent when they lost field containment.
But a gravitomagnetic core with a highly nonlinear gravitomagnetic permeability could provide all of the effects that we’re talking about here without the huge mass requirement.
So, again, we're back to magic in my mind.
Because matter is pretty pretty much transparent to gravity waves.
Gravitational-wave astronomy - Wikipedia
You haven't understood the point about gravitomagnetic permeability; it has nothing to do with matter's inherent transparency to gravitational waves. Atomic nuclei intrinsically couple the magnetic moment with the gravitomagnetic moment, which is a good starting point. And some nuclei, like Uranium, possess an interesting quadrupole by virtue of their nonspherical deformation.
It's going to take a deep love of theoretical physics, a creative and technical brilliance, patience, and eventually some very challenging experimentation, to make the breakthrough in field propulsion technology that will usher in an era of practical manned interstellar spaceflight.
About the only thing going for us, beyond our own primitive understanding of physics, is the fact that someone, or something, has provided breathtaking aerial demonstrations that prove (to me anyway) that it can be done.