Energy and proper time (not relativity)

dapias09
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Hi guys,

In a scientific paper, I have found the following sentence:

"...given the fact that the system is homogeneous in energy, or equivalently, that it has no proper time scale."

I'm not sure about what the authors intend to say (what is the relation between being homogeneous in energy and having (or not) a proper time scale). I know the relationship of energy and time as conjugate variables in the formalism of quantum mechanics but this paper is about linear thermodynamics.

Perhaps you interpret this better than me.

Thanks in advance
 
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The "homogeneous energy" state means that the energy is the same everywhere. In that case the system is static - there is no natural change to the system, and hence time is not meaningful.

Think of a can full of warm air at the same temperature as the ambient air. About the only action left is diffusion.
 
Thank you @UltrafastPED, would one example about a proper-time scale be the average time of reaching the thermal equilibrium?
 
I'd have to read the paper to see what the author had in mind ... but that seems reasonable.

That is, your system requires some dynamics.
 

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