3 ms·

My understanding of the subject is limited, but doesn't this experiment make the the tardigrade the actual "observer" of the quantum state ?

• jfengel 5y ago
  They're too cold to be "observers". The "observer" thing is something of a red herring. It's a very old misunderstanding of quantum mechanics that attracts a lot of attention despite being discarded a very long time ago. What happens is that entangled states are unstable. It's very hard to extend them to larger, more energetic objects without de-stabilizing them. Since human beings are "large, energetic objects", anything we do necessarily causes the state to "decohere" (fall into one state or the other). But that's not because we're "observers". We just happen to be observing. This experiment works (if it does) because the thing was frozen to almost absolute zero, and this stopped being an energetic object. It's remarkable that you can do that to tardigrades at all, though it's still not really clear that they were actually part of the entanglement.