The science behind anti-gravity items and forces have been studied heavily for a long time. There are many ways to give something the appearance of floating in the air, but how many things actually do it? In this video, Derek Muller shows how to use the force of gyroscopic precession to make something truly defy gravity.
At the start of the video Derek and another muscular man try and lift a 42 pound weight on a bar with one hand. This is obviously quite difficult and neither can do it, that is until they spin the weight at 2500 rpm then it simply floats around in a circle by itself.
While it may not truly be an anti-gravity bar, the science behind it is sound and the illusion is amazing to watch.