Why is no one taught the one concept in quantum physics which denies reality?

It’s called contextuality and it is the essence of quantum physics

Chris Ferrie
6 min readAug 9, 2021

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Photo by Ehud Neuhaus on Unsplash

This morning I had a bowl of plain Greek yoghurt and toasted muesli for breakfast. I could have had a plain bagel with mashed avocado — or, I could have had nothing at all. But I had the yoghurt and muesli. I know, I know, damn millennials and their hipster breakfast food. But, also, who cares what I ate for breakfast? Well, perhaps the universe does.

Imagine that, after breakfast, I dutifully went to the lab to perform some quantum physics experiments. The results of the experiments obviously depend on what I do in the lab. But, they shouldn’t depend on what happens outside of the lab, right? I mean, why should laser light bouncing around through crystals and mirrors care what the current value of the S&P 500 is, let alone what I had for breakfast?

The conditions under which an experiment is performed are called its context. In practice, the contexts we consider are very limited to a few settings on the devices in the lab. But, maybe the temperature of the room is important. Were the lights on? Was the door open? Especially when things go wrong — which is more often than not — the context is where you look for answers. But some parts of the context are…

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Chris Ferrie

Quantum theorist by day, father by night. Occasionally moonlighting as a author. csferrie.com