Is it or will it ever be possibel to build and antigravity machine?

Answer 1

It is more like an anti-gravitational simulation, but there are in fact devices that use magnets and electricity to produce propulsion. Various lifter have been constructed , check out this link: http://www.americanantigravity.com/blogs/15/Biefeld-Brown-Vacuum-Testing.html
Also, there are many discoveries going on, so we might actually be able to create a warp drive (much UN-like the one in Star Trek, though)

Answer 2

The kind of energy for this operation is availabe, known as dark energy. Dark energy is a mysterious energy that acts as a form of antigravity, opposing gravitational attraction. But dark energy reacts very weakly with ordinary matter (which is why it's called dark energy), so it would be very difficult for ordinary matter to interact with it, let alone make a machine.

But in a sense, the universe is itself an antigravity machine, sine approx. 75% of the universe is filled with dark energy. This is why the universe is expected to expand infinitely, because dark energy overwhelms gravity on a universal scale.

Answer 3

I have learned over the years to never say never.
Gravity is generally accepted today as the result of space deformation caused by large objects. However, tomorrow or the next day, a new theory may well emerge that makes the invention you speak of more attainable.
If you hold me to a definite answer, I'd have to say yes - in my opinion, someday, someone will indeed invent an anti-gravity machine.

Answer 4

The floor or a chair is an effective device which you seek.

Answer 5

gravity is the result of the curvature of space-time, so No.