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A revolutionary theory by physicist and mathematician Ginestra Bianconi of Queen Mary University of London proposes that gravity is derived from quantum relative entropy. This unexpected solution could be the key to solving the long-standing problem of unifying general relativity and quantum mechanics, offering a new perspective on the fundamental laws of the universe.
The idea of connecting entropy with gravity may seem paradoxical, since entropy is associated with chaos, and gravity with the ordered structure of the cosmos..
Reconciling two irreconcilable theories
Einstein's general theory of relativity describes gravity as the warping of space-time by massive objects. It operates on cosmic scales and explains why the Earth orbits the Sun, moving along a path in warped space-time.
Quantum mechanics, on the other hand, describes the universe at a subatomic level, where particles behave both as matter and as waves. These two fundamental theories have long seemed incompatible, creating a serious obstacle to understanding physics at the deepest level.
Bianconi proposes to consider space-time as a quantum operator acting on quantum states. This allows us to use quantum entropy to describe the interaction between space-time and the matter that exists within it.
Quantum entropy as a bridge between theories
Quantum entropy measures the unpredictability or disorder of a quantum state. By using it to define the differences between matter and space-time, the new theory modifies general relativity.
It initially gives the fabric of space-time low energy and small curvature. This allows us to predict a small cosmological constant that explains how and at what rate the universe is expanding.
The theory also introduces the concept of the G-field, or gravitational field. This is a vector field that has both magnitude and direction, and explains how space affects objects. Bianconi uses the G-field as a Lagrange multiplier to find the maximum and minimum of the quantum wave function.
Potential connection to dark matter
If gravity can exist in the form of particles, it opens up an interesting possibility: the G-field could explain the nature of dark matter.
Dark matter remains one of the greatest mysteries of modern physics. It makes up about 27 percent of the universe, but its particles have never been directly observed. If a new theory is correct, gravitational particles could explain this mysterious substance.
Although Bianconi's theory still needs experimental confirmation, it offers an elegant solution to two fundamental problems in physics: unifying quantum mechanics with general relativity and explaining the nature of dark matter.
Paradoxically, the chaos represented by entropy may be the key to understanding the order in the universe embodied by gravity. The irony is that it is disorder at the quantum level that can give rise to the ordered structure of the cosmos.
