Experiments have shown that Newton’s law of universal gravitation is applicable to two masses with a mass less than 100 milligrams. Measuring such a weak gravitational field can penetrate into the quantum world and help dark matter research.
The four basic forces of nature are strong nuclear, weak nuclear, electromagnetic and gravity, This is still an unknown.Although it is easiest to understand and perceive on a human scale-objects fall with the same acceleration, the earth attracts us, etc.-for Theoretical physics.
Gravity cannot meet the standard model of particle physics, as is the case with the other three interactions. It seems that it is separated from quantum theory, and the experiment trying to measure it cannot be separated from the gravity that already exists on the earth.
but now, University of Vienna (Austria) and Institute of Quantum Optics and Quantum Information (Favorites) Established an experiment that used tiny golden balls of 90 milligrams and a radius of 1 mm. Through these golden balls, they managed to isolate Minimum gravitational field It has been measured so far.
Prior to this, tests used to test the nature of gravity in a controlled environment used macro-mass, which weighed ten times that of the Austrian study.
As explained to SINC Hans Hepach, The co-author of this work is a PhD in Physics from the University of Vienna. This experiment is very important because until today, does gravity require a quantum description of the “minimum size and mass; through these experiments, we can see how gravity is in an object close to a quantum state.” which performed.”
Hepach emphasized: “Our experiment is the first step in this direction.” He added: “This measurement can pave the way for experiments in exploring new areas of fundamental physics, such as dark matter detection or quantum physics. The interaction between them. And gravity”.
Authors, their research is published in Last issue natural, An experiment was designed to isolate gravity as a coupling force between two small balls. These tests require a “nearly perfect isolation” environment to observe and observe the behavior of this force.
The configuration of the experiment can use the following methods to minimize the influence of external interference: Faraday Shield Stop electrostatic force. In order to reduce the impact of earthquakes and sound, one sphere is connected to the vacuum chamber, and the other sphere is periodically pulled closer, so that the sphere can be isolated. Gravitational coupling, Can be detected by the change of the rotation signal.
To twist the pendulum, the gravitational interaction between two golden balls has been measured. /Tobias Westphal/University of Vienna
The result is consistent with what I expected Newtonian Classical Physics: The gravitational interaction between these two objects depends on their mass and the distance between them.
How to (try to) isolate gravity on the earth
In order to be isolated from the gravity of the earth, Torque balance miniature. The instrument consists of a pole suspended on a high-rigidity cable, which acts on the earth’s gravity in the vertical direction.
But on a horizontal surface, the cables can be easily twisted together Spring constant This is a small force, which allows a small force applied to the plate to cause a large rotation of the rod.Therefore, there is a An environment with almost no gravity (Or more correct in microgravity) so that experiments can be carried out.
He stated in a parallel article in the journal Science: “This is very suitable for determining very small forces, such as those caused by the gravitational interaction of a golden ball. ” natural Researcher Christian Rothleitner, Is a member of the German Federal Institute of Physics and Technology (PTB).
Hepach expects that the research team is already working with A more controlled environment“We recommend improving the gravitational detection system, conducting experiments far away from traffic and quiet places, and improving the oscillator to reduce internal losses and further increase sensitivity.”
Westphal, T., Hepach, H., Pfaff, J. And Aspelmeyer, M. “Measurement of gravitational coupling between masses in millimeters”. natural (2021). DOI: 10.1038 / s41586-021-03250-7.