Over the decades antigravity has been the stuff of science fiction, though there have
been many inventions purporting to be antigravity devices, from gyroscopic lifters to superconducting
magnets, so far there has been nothing that is truly capable of nullifying, shielding
or modifying what we know as gravity, so could a form of antigravity even be possible given
our current understanding? Just to be clear, what I’m referring to
when I say antigravity is a way to either nullify or modify the effect of gravity that
does not rely upon other forces like electromagnetism or some form of thrust for example.
Whether this would be some kind of local effect that creates a negative form of gravity or
modifies gravity so that its effect is increased or decreased.
Almost everything so far which is claimed to have been a form of antigravity is really
just using other known forces though there is a very interesting effect which if verified
could be the closet we have come so far and we will look at later.
A plane might be called an antigravity machine because it can lift you up and away from the
surface of the earth but it's actually using the pressure differential of a wing traveling
through the air at speed to create lift. A rocket does a similar thing but by burning
fuel which expands rapidly creating thrust pushing it along, and with enough thrust,
it can overcome the pull of the earth’s gravity but its nothing more than a chemical
reaction. In the 1980 & 90’s, Gyroscopic Inertial
Thrusters were seen as potential sources of reactionless thrust. When seen in action they
appear to be able to generate lift and defy gravity. They use various methods of leverage
against the support of a large gyroscope or flywheel, this appears to generate lift when
the angle of the gyroscope is changed but after years of theoretical and laboratory
testing by NASA and others, no thrust or antigravity forces in free space was found to be produced.
Other so-called antigravity lifters using the Biefeld–Brown effect are in fact using
the propulsive force of ion flow. By charging a very lightweight object or lifter with usually
a positive high voltage the surrounding air is ionized. As the ions are attracted to the
opposite negative electrode usually on the ground they interact with the neural air molecules
creating an airflow with enough force levitate the lifter.
While some claimed the that the effect works in a vacuum and therefore it must be is some
form interaction between the electric field and the earth’s gravity field and implying
that it could be used to create an antigravity effect, when NASA tested it in a vacuum equivalent
to that found at a low earth orbit, the effect disappeared proving that it was caused by
the propulsive force of ions pushing the air. Although gravity is one of the fundamental
forces and thus antigravity would be theoretically impossible. It been proposed that if another
force that could attract matter or repel it like a theoretical antigravity then maybe
a machine could be made that simulate that effect.
In scientific papers published between 1991 and 1993, American scientist Ning Li claimed
that antigravity effects could be achieved by if the ions in a Bose–Einstein condensate,
that’s a state of matter were all the atoms in it can act like one, could be trapped into
high temperature superconduting disc with a time-varying magnetic field, a huge amount
of energy could be stored in its lattice structure. As each ion would spin rapidly it would create
a tiny gravitational field, however because all the ions from the Bose–Einstein condensate
would be aligned the effect would be magnified by the billions of ions in the disc.
The theory is that this would create a gravity-like field that could either increase or decrease
the effect of gravity which Ning Li called AC gravity because it could be attractive
or repulsive in nature. She said that experiments in the lab had created beam-like effect above
the disc which affected matter for some distance and this backed up the theories.
Even though it created a lot of interest at the time, in 1997 she published another paper
that saying the new measurements with a more sensitive gravimeter had shown it’s effect
to be either very small or nonexistent. In 2000 Ning left the University of Alabama
and set up her own company AC Gravity LLC and in 2001 was awarded a grant worth just
under $450,000 from the DOD to investigate it further. Since then she has all but disappeared
and nothing more has been heard about her research but the company AC Gravity LLC is
apparently still in business. Experiments carried out by Yevgeny Podkletnov
in the early 1990’s using rotating Superconducting disks in a magnetic field claimed to decrease
the effect of gravity by about 2% on objects placed above the disc and again it appeared
to act like a beam above the disc for a considerable distance.
However these results had not been able to be verified by other scientists. He claimed
that the other researchers had not used the same setup and that’s why they couldn’t
reproduce the results and when NASA was about to complete the experiments they ran out of
funding and the research was taken over by the Dept of Defence and he was shut out of
any further research in the US because of his Russian citizenship.
This and Ning Li’s work is said to have prompted Boeing to investigate the effect
of rotating superconductors with project GRASP - Gravity Research for Advanced Space Propulsion,
with potential uses including space launches, artificial gravity on spacecraft, aircraft
propulsion and fuel-less electricity generation. Though others have pointed out that if the
effect could be proven and directed into a beam it would be able to be weaponized, creating
a steerable artificial gravity force to destabilize, missiles, planes, and satellites.
Since the information was released, Boeing has backtracked and said that it was offered
the proposal but chose not to fund it with company money but refused comment if it was
a black project on the company books. These and others are based on the idea Gravitoelectromagnetism
which looks at analogies between Maxwell's equations for electromagnetism and Einstein’s
equations of relativistic gravitation. Basically, the premise is that just as a spinning
electron creates a magnetic field, then a massive spinning object like the earth would
create a drag on spacetime, a bit like when you spin a ball in a viscous fluid like oil.
Although this drag was predicted nearly 100 years ago, Einstein called it “frame dragging”,
it's taken the best part of a century to prove if it actually existed with several independent
satellite missions which did indeed measure a small but noticeable dragging effect.
This is important because our current theories of gravity are that mass curves the otherwise
flat spacetime and this deforming of spacetime is gravity. This is shown quite well with
the weight in a rubber sheet experiment that represents the sun and pulls the sheet down
in the center. A ball rolling in a straight line follows the curve, this is like the earth
which is travelling in a straight line but its caught in the curve of spacetime created
by the sun’s mass and so long as the earth’s speed is constant it orbits the sun.
If the frame-dragging effect is real, then it is affecting gravity and a moving object
near a massive rotating object would experience acceleration not predicted by Newtonian laws.
It’s been suggested that this effect is what might be behind the massive jets of gas
which are ejected from quasars and galactic nuclei. Rotating supermassive black holes
at the centres of galaxies would also create enormous frame-dragging effects.
This is where the spinning superconducting discs in Nign Li’s and the GRASP experiments
come in, to simulate this frame-dragging and the gravitational warping effect but on a
very much smaller scale. But the elephant in the room is that we still
don’t know what gravity really is. Yes, we have Newtons and Einstein’s laws which
predict with amazing accuracy the effects of gravity but these theories don’t tell
us how gravity works or what the mechanism is that makes mass bend spacetime, all we
know is that gravity is a consequence of mass, the greater the mass the greater the bending
of spacetime and hence the greater the gravity. Although gravity works over huge distances
on the grand scale of planets, stars and galaxies we don’t know how it really works on very
small things at distances on the atomic scale because its effect is then so weak and difficult
to measure. Conversely, we don’t know how it works where gravity is incredibly strong
such as in a black hole. There are many theories as to how gravity
actually works but none which have been proven. In quantum mechanics, there is a prediction
that a force-carrying particle called a graviton might exist even though we have found no proof
of their existence. But as all the other three fundamental forces, the strong nuclear force,
the weak nuclear force and the Electromagnetic force have at least one force carrier, its
believed there must be one for gravity to, if gravity is a true force.
Gravity appears to have virtually no interaction with any of the other forces and works on
any form of matter, even ones which we currently cant not detect, namely the still unknown
dark matter. There is no known way to shield against it because it bends spacetime which
is the underlying fabric of the universe and as such it’s not really a force. We only
feel its effects when we are stopped from moving like when we are standing on the ground
but being pulled by the mass of the earth below us. If we were free-falling in space
just above the earth we would not feel it at all.
Then there are the observations of the physical universe that show the rate of expansion from
the big bang is speeding up instead of the expected slowing down under the effect of
gravity. So either we a major problem with our theories of gravity or there is something
else that is providing a yet unknown force which is overpowering gravity and pushing
the universe apart in all directions which we currently call “Dark Energy”, and like
dark matter we can not detect directly but only see the effect it has, a bit like gravity
itself. So given all this, is true antigravity or
some form of gravity control a realistic proposition?, we still don’t know if anything really has
come from the research by Ning Li and Project grasp, it’s been rather quiet on that front
in recent years. A source at NASA said that the science appeared sound but the difficulty
was in scaling it up. Maybe at some point in the future when we
have a much better understanding of what gravity is and how it really works we will find a
way to manipulate it as we want, but unless a new breakthrough is announced it still appears
to be in the realm of science fiction. Brilliant
Although we might not have a complete theory for gravity for many years to come its not
for the want of trying, there are dozens of competing theories from some of the brightest
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