Quantum physics, Timothy Leary, the movie “The Matrix” and alternate realities all presented together in one short article had me, too, pondering: How real is our reality?
The latest ideas percolating around that question come from British physics genius Stephen Hawking and Caltech theoretical physicist Leonard Mlodinow. In their controversial new book, The Grand Design, they suggest there may be no single theory that unifies all of physics. They sum up their thoughts in an essay co-authored for this month’s Scientific American magazine, titled The (Elusive) Theory of Everything.
Hawking and Mlodinow conclude there is no theory-independent concept of reality. They have adopted instead a view they call model-dependent realism: the idea that a physical theory is a model (generally of a mathematical nature) with a set of rules that connect the elements of the model to observations.
The scientists illustrate this idea with goldfish swimming in a curved fishbowl: “Their view is not the same as ours from outside their curved bowl, but they could still formulate scientific laws governing the motion of objects they observe on the outside. For instance, a freely moving object that we would observe to move in a straight line would be observed by the goldfish to move along a curved path. The goldfish could formulate scientific laws from their distorted frame of reference that would always hold true and that would enable them to make predictions about the future motion of objects outside the bowl. If the goldfish formulated such a theory, we would have to admit the goldfish’s view as a valid picture of reality.”
According to Hawking and Mlodinow, it might be that to describe the universe we have to employ different theories in different situations. Each theory, they write, may have its own version of reality, but, according to model-dependent realism, that diversity is acceptable, and none of the versions can be said to be more real than any other.
I think it’s exciting that ideas about physical reality are being reconsidered. These two renowned physicists asked “How do we know that the reality we perceive is true?” Now I wonder… is it so unreal to imagine that they or any other scientist may someday be asking if we create the reality we perceive?
