Superdeterminism makes sense of the quantum world by suggesting it is not as random as it seems, but critics say it undermines the whole premise of science. Does the idea deserve its terrible reputation?
I’VE never worked on anything so unpopular!” Sabine Hossenfelder, a theoretical physicist at the Frankfurt Institute for Advanced Studies in Germany, laughs as she says it, but she is clearly frustrated.
The idea she is exploring has to do with the biggest mystery in quantum theory, namely what happens when the fuzzy, undecided quantum realm is distilled into something definite, something we would experience as real. Are the results of this genesis entirely random, as the theory suggests?
Albert Einstein was in no doubt: God, he argued, doesn’t play dice with the universe. Hossenfelder is inclined to agree. Now, she and a handful of other physicists are stoking controversy by attempting to revive a non-random, “deterministic” idea where effects always have a cause. The strangeness of quantum mechanics, they say, only arises because we have been working with a limited view of the quantum world.
The stakes are high. Superdeterminism, as this idea is known, wouldn’t only make sense of quantum theory a century after it was conceived. It could also provide the key to uniting quantum theory with relativity to create the final theory of the universe. Hossenfelder and her colleagues aren’t exactly being cheered on from the sidelines, however. Many theorists are adamant that superdeterminism is the most dangerous idea in physics. Take its implications seriously, they argue, and you undermine the whole edifice of science.
So what is the answer? Does superdeterminism deserve its bad reputation or, in the absence of a better solution, do we have little choice but to give it a chance?
Quantum theory describes the behaviour of matter at its most …