Antigraviatation or antigravity means silent levitation. Normally those systems use magnetic levitation. But maybe we someday can make the system that can turn gravitation opposite.
1) The electromagnetic or so-called "virtual anti gravitation" is possible. And that thing can use in the next-generation hyper-speed "maglev" or magnetic levitation trains.
In virtual antigravitation, the system uses magnetic levitation, or a well-known phenomenon where the same poles of magnets are pushing the objects above the ground. Things like maglev or magnetic levitation trains are using this type of system.
The magnetic levitation trains can cross the speed of sound very easily. And they can combine with hyper loops. If the hyperloop train is traveling in the vacuum tube and the magnetic gauss system pulls that thing ahead. That system can make a revolution in transportation.
The train levitates in the vacuum tube. And magnets transport it ahead. The principle of the system is similar to particle accelerators. The speed of those vacuum trains can be higher than aircraft because there is no friction.
2) The laser ray can make a high-energy area below the craft.
In the image above this text, the antigravitation system makes the bubble under the craft. The film where that image is taken is lower in this text. The idea is that the energy that is transferred to the particles below the craft makes the cushion. That energy cushion is lifting the system above the ground.
In some other visions between craft and ground is made the electric arc. And the high-temperature gas is pushing the craft above the ground. The effect of that thing can boost by blowing air sideways above the craft. That thing makes the underpressure area above the craft. And it pulls the craft upward.
3) Ion-based systems (Futuristic models)
Image 2) In that anti-gravity system. The tornado-shape ion vortex levitates the object. So the system is based on the idea of the ion engine that uses an extremely dense ion pillar. That thing allows hovering the craft above the ground by pushing ions to the ground.
The magnetic field in the superconducting ceramic wheel is ionizing air. And the magnet above the ion field is pushing the ionized gas through the magnetic accelerator.
The idea of another ion-based system is simple. The craft is hovering between two ion cushions. The ion cushion below the craft push. And the ion cushion or ion cloud above the craft pulls it upward. There are holes in the body of the craft. And then below the craft is formed the negative and then above the craft is made positive ion cloud.
The ions flow through the holes of the craft pushing it upwards. And that kind of system can make the craft levitate silently. The ion clouds can explain the electromagnetic phenomenon that is connected with the UFOs:s.
3) The plasma-based systems. (extremely futuristic model)
There is the possibility that the ball-shaped systems can use plasma with a high energy level to push the craft above the ground. The core of the craft might be made by using graphene. Then inside it will happen the annihilation reaction that causes the formation of the ion could be outside the craft.
The system can have ventilation that bases on an ion system that determines the direction of the main impulse. And that extremely powerful system can adjust its moving direction by adjusting the symmetry of the plasma ball around it. The idea is that the plasma that is outside the ball is the thing that hovers.
The plasma is anchored to the structure of that system and it pulls the craft upward. The idea is similar to the hot air balloons where the gondola is in the middle of the balloon, not below it. But in the case of the plasma levitation, the physical balloon is replaced by using plasma.
https://en.wikipedia.org/wiki/Maglev
Image 2) https://science.howstuffworks.com/innovation/science-questions/antigravity.htm
