In her book, “Black Hole Survival Guide,” professor and theoretical physicist Janna Levin suggests that gravity may not exist as a fundamental force. In science, we attempt to understand life on many levels, but at this stage in the process, our understanding of gravity is still quite macroscopic because we do not yet have a clear picture of the details of what is happening at the quantum level. Our understanding of gravity is derived primarily from this macroscopic view: we know how objects fall from the sky, how planets remain in orbit around the sun, and how, according to Einstein, heavy masses produce curves in spacetime that affect other heavenly bodies. These are all understandings derived from the macroscopic view.

 

However, when we zoom in closer to the quantum level (which is trillions of times smaller than the atomic world), we might no longer have something that can be recognized as gravity. Rather, gravity might be an emergent property that arises out of multitudes of “chaotic, quantum-entangled overlaps,” as Levin puts it. To further explain this idea, she uses the analogy of a “pointless” painting in which no individual paint marks or points can be seen at the macroscopic level. At this level, the painting has meaning that can be readily recognized. But as we zoom in, we begin to see only patterns of dots. The painting loses all familiarity and meaning and now is entirely unrecognizable. In this analogy, the painting itself only emerges as a result of all of these tiny placements and interactions of dots. As a “fundamental force,” so to speak, the painting does not exist at this level.

 

Levin goes further to illustrate how something like gravity can emerge from the quantum level without necessarily existing at the quantum level itself. Temperature, for example, cannot be found as a fundamental property in water molecules. Instead, temperature appears to be an emergent property that comes about as a result of the interaction of all the energies associated with millions of water molecules meshing with one another. The sum of their interactions is much greater than the individual water molecules themselves, producing the emergent property of temperature.

 

If this theory is correct, it would help unify the macroscopic forces in physics (i.e., electromagnetism, the weak and strong nuclear forces, and “gravity”) with quantum physics, thereby accomplishing a long forgotten dream of Einstein. We’ll just have to see where this leads.