Einstein and Wheeler: Is the Moon There Whether We See It or Not?

Photo by Pedro Lastra on Unsplash

Are we participants in bringing the universe we inhabit into existence? Quantum physics showed observers play a unique role in the actions of particles. This led physicist John Archibald Wheeler to propose the strange idea that observation creates our world. Einstein disagreed. But Wheeler’s ideas are gaining momentum in part because of the Holographic Principle.

Einstein didn’t seem to like quantum theory very much. The ideas that emerged a little over a hundred years ago, many from Copenhagen, didn’t fit very well with his picture of the world. He upended the classical view of nature with his theories of relativity. Light bends? Spacetime is like a rubber sheet, deforming in response to mass? Time is relative to the motion of observers? These were mind-bending but still worked with his strong preference for an objective, local, and deterministic universe. When the quantum theories led to a strange, incomprehensible world, he fought back.

Heisenberg’s Uncertainty Principle undermined determinism, and Einstein dismissed it by saying God doesn’t play dice. The measurement problem, where the properties of matter were only probabilities until they were measured, undermined an objective, realistic world. Einstein responded by asking if the moon was still there even when he wasn’t looking at it. Then there was…