What is mean anti-gravitational force & its uses in modren physics???

Question

What is mean anti-gravitational force & its uses in modren physics???

Answer 1

Strictly speaking, anti-gravity force should be something that is similar to gravitational force ( must be propagated the same way as how gravitational force is propagated) but with a reverse effect, which is repulsion instead of attraction.

So far an honest-to-goodness anti- gravitational force has not yet been propagated simply because we are still at a loss on how gravity is generated by a body.

There have been a lot of theories about gravity, from that of the effect of the curving of the fabric of space and time, to the more recent ones which are based on Complex Quantum Mechanics. But there is still the burden of proving the veracity of a theory and the proof to this would be the propagation or generation of anti- gravity.

While the floating of superconductive material ( Metallic material cooled down to a temperature of almost absolute zero by bathing it with liquid nitrogen) is sometimes claimed as a case of anti-gravity propagation, there is still a need to explain this in terms of valid Physics principles and a sound theory of gravity.

In the actual therefore, anti- gravity is still a dream because gravity is not yet defined  by Physics even at the CQM level.

If we can find the answer to the question on how gravity is propagated, then we will have the framework for building an absolute propulsion system which will enable us to travel across interstellar space.

Answer 2

For people, actually the best anti-gravity device is the earth itself. Since it is the earth that keeps you from falling to the center of the gravitational field. Plus it is what supports the building your chair happens to be in or the patio it is on or wherever it happens to be (except airplanes, UFOs, etc).

Answer 3

After publishing his General Theory of Relativity in 1915, Einstein explored the consequences of his gravitational field equation.

G = 8πT

In a paper titled 'Kosmologische Betrachtungen zur allgemeinen Relativitatsctheorie' (Cosmological Considerations on the General Theory of Relativity) published in 1917, Einstein  found that to model a steady state universe, which was the then favoured model, he had to bastardise his field equation into the parameterised form: -

G(μν) - λg(μν) = -κ(T(μν) - ½g(μν)T)

Where the constant(?) 'λ' is the cosmological constant or a 'fudge factor' that Einstein introduced to make his field equation work for a steady state universe. When Edwin Hubble discovered, in 1925, that the universe was expanding, Einstein commented that this constant was the greatest blunder of his life. It seems that Einstein ignored the implications, implicit, within his field equation that the universe is expanding!  

However, a modern interpretation of this constant is that it represents a repulsive aspect to the gravitational force. The repulse force could be viewed as anti-gravity!

Wikipedia, the free encyclopaedia comments, 'In 1998, observations of type Ia supernovae ("one-A") by the Supernova Cosmology Project at the Lawrence Berkeley National Laboratory and the High-z Supernova Search Team suggested that the expansion of the universe is accelerating'. this acceleration is attributed to the presence of 'dark energy'. However, Wikipedia, the free encyclopaedia further comments, 'The simplest explanation for dark energy is that it is simply the "cost of having space": that is, a volume of space has some intrinsic, fundamental energy. This is the cosmological constant, sometimes called Lambda (hence Lambda-CDM model) after the Greek letter λ, the symbol used to mathematically represent this quantity. Since energy and mass are related by E = mc², Einstein's theory of general relativity predicts that it will have a gravitational effect. It is sometimes called a vacuum energy because it is the energy density of empty vacuum.....The cosmological constant has negative pressure equal to its energy density and so causes the expansion of the universe to accelerate.'

I hope this is of some help!

Answer 4

Anti-gravity is a force which opposes gravity.

The best anti-gravity device invented to date is called a chair.  You sit on it and it exerts a normal anti-gravity force on your rear.  Brilliant engineers have invented thousands and thousands of similar devices to overcome gravity.