The knowledge of universal gravitation tells us that objects will fall downward under the action of gravity, which is an indisputable law of physics. However, a scientific research team from the University of Arts and Sciences in Paris, France recently showed people a device that can make objects realize the anti-gravity .
anti-gravity device, the boat can float under the liquid layer
First, the researchers made a in a container through high-frequency vibration to create a solution layer suspended in the air , this solution layer is in Continuous droplets will not be formed under mechanical vibration with a frequency of 100 MHz, so the liquid will not drip down and squeeze out the air below. After this suspended liquid layer was formed, the researchers placed various objects with a density less than the liquid under the liquid layer and found that these objects can be suspended in anti-gravity .
A single-layer liquid suspension (left) and a double-layer liquid suspension (right) device
Researchers said that this anti-gravity device does not violate the laws of physics, this anti-gravity The existence of is caused by anti-buoyancy. Under normal circumstances, gravity tends to pull the object downwards, and when the object displaces the surrounding liquid, it will produce an upward buoyancy, thus maintaining the balance of forces. But there are some subtle differences in anti-buoyancy. Under the action of vibration, the liquid exerts a vertical upward buoyancy on the object, thereby maintaining a balance with the vertical downward gravity.
positive buoyancy and anti-buoyancy
However,The anti-buoyancy force on the earth is more sensitive to the external vibration frequency and the density of the object. Once the vibration frequency drops to a threshold or the density of the object is too high, the object will fall from the suspended liquid.
The external vibration frequency decreases or the density of the object increases, and the anti-buoyancy force is less than gravity, the object will fall
Ruth, KS, Day, FR, Hussain, J. et al. Genetic insights into biological mechanisms governing human ovarian ageing. Nature 596, 393–397 (2021).
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