Statistical mechanics helps relate the quantum world to objects that seem solid and not governed by the whims of observation, but there are still questions to be answered, says Chanda Prescod-Weinstein
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I RECENTLY walked by a physics department office that had a sticker on it saying something like “Heisenberg may or may not have been here”. This is in part a nod to the quantum cat, which, while it is inside a box with no observer, may be dead or alive. We aren’t sure until we look at it.
This feline thought experiment is intended to help us visualise a deep conceptual difficulty in quantum mechanics: the fact that the act of observing seems to determine what state matter is in. This is due to the probabilistic nature of quantum mechanics …
