Relationship between measurement and temperature

[Jimster41]

A system at absolute zero (ground state) can't be be divided into observer and observed, can it?

I'm struggling with the relationship between superposition, decoherence and temperature. Decoherence requires information. Information requires energy. Though multiple basis of "information" can support decoherence or inhibit it (all kinds of properties can be measured, or not measured) Temperature factors into all of those doesn't it?

 

[julcab12]

A system at absolute zero (ground state) can't be be divided into observer and observed, can it

Yes. In Quantum Theory there is still energy-- Vacuum State / lowest possible energy state of a quantum system. It has quantum fluctuations consistent with the ΔEΔt>h Uncertainty Principle. In GR, we can create a mental picture of zero -- Minkowski spacetime.

In other words can decoherence occur in a system entirely at ground state? If not does that mean a system at ground state is in superposition? Or maybe I'm confused about whether things can be said to exist in that sense of ground state. And I'm just saying the vacuum contains nothing, is nothing... But then is the vacuum a superposition

Depending on what you meant by vacuum(GR vacuum, QM vacuum and FT vacuum. In FT vacuum ground state is separated by fields. It only happens when interaction occurred which in term modify the once FT vacuum to the usual QM vacuum (lowest energy) where all the weird stuff is happening.

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