Comment: the thermodynamic temperature

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the thermodynamic temperature

the thermodynamic temperature T is given by

T == dE/dS where dS is not zero

So they are describing

a negative change in Energy and a positive change in entropy
a positive change in Energy and a negative change in entropy

By reducing the entropy through adding constraints while the energy stays the same could be a "negative" temperature.

Some molecules reduce their entropy while increasing their energy.

It seems misleading to refer to this as below absolute zero.

Perhaps thermodynamic temperature is relative to the system studied and the reference to absolute zero a misnomer.

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