Source: New Scientist

WANTED: DEAD AND ALIVE! When it comes to Schrödinger’s cat, the hipster T-shirts write themselves. The zombie feline in an ambiguous state of animation fascinates the wider world. For quantum physicists, it is more of a tormentor, clawing at their belief in a treasured theory and coughing up hairballs over its claim to provide true enlightenment about the workings of reality.

Scram, moggie. Schrödinger’s cat has just had an upgrade, and if you had a feeling the original was weird, it has nothing on the new one. Instead of placing a cat into an indeterminate state of dead-and-aliveness, a new scenario doing the rounds involves pulling off a similar trick with people who are themselves performing and observing a Schrödinger’s cat-type experiment.

The reasoning is that if quantum theory is a universally valid theory capable of making sense of reality, it should be able to describe people using quantum theory. But this turns out to be a thought experiment in the best tradition of quantum bamboozlement. It blows up, providing a nonsensical answer that, taken at face value, removes our last tenuous handholds on the nature of quantum reality.

Possibly. There is seemingly never any absolute certainty when it comes to quantum theory. But while some physicists continue to debate the true significance of the result, others see an opportunity in it, a clue to where a more powerful theory of the world’s fundamental workings might lie.

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