Quantum mechanics is the basis of almost everything we know about the laws of physics. Using it, scientists describe both the force fields of fundamental forces, such as electromagnetism or nuclear forces, as well as matter, using these elements to assemble increasingly advanced theories explaining the functioning of the cosmos. This puzzle is still missing a key element – a quantum description of gravity. Why wouldn’t it meet its basic assumptions?
Gravity, previously best described by Einstein’s theory of general relativity, remains a classical phenomenon. Unlike other interactions, it has not yet been captured in the framework of quantum mechanics. It’s a discrepancy that has been one of the biggest challenges in modern physics for decades. The lack of a unified theory combining classical gravity with quantum mechanics is of great interest to scientists because determining this phenomenon could fundamentally change our understanding of the universe.
Research published in Physical Review Letters propose a quite interesting method to investigate the quantum nature of gravity. Instead of trying to directly prove its quantum nature, the researchers decided to test whether gravity obeys the basic principles of quantum mechanics — such as superposition. This is a state in which an object – in the case of the proposed method it is a microscopic crystal – can be in two places at the same time until it is measured.
The experiment involves putting the crystal into a state of superposition and then carrying out two different tests. In the first study, the state of the crystal is recorded, which acts as a kind of control group. In the second, a second nanocrystal is placed close to the first crystal. Theoretically, the weak gravitational force acting between them should affect the state of the first crystal.
The researchers plan to test whether this interaction changes the state of the first crystal in a manner typical of a typical phenomenon in quantum mechanics, which is described as “measurement-induced disorder.” If the measurement shows differences in the state of the crystal after the gravitational interaction, it could provide the first evidence for the quantum nature of gravity . We wouldn’t get a full theory in this case, but… it would be a good first step in this matter.
As the study authors emphasize, these tests can help determine whether gravity works according to the principles of quantum mechanics or whether it requires a new, non-classical theory. The road to completely solving the puzzle of quantum gravity will undoubtedly be long, but the success of these experiments would open new possibilities in research into the nature of the universe. And we would get rid of an important gap in the context of the relationship between gravity and modern physics.
Source: antyweb.pl
