> As physicists have worked to unite seemingly disparate fields over the past century, they have cast entropy in a new light — turning the microscope back on the seer and shifting the notion of disorder to one of ignorance. Entropy is seen not as a property intrinsic to a system but as one that’s relative to an observer who interacts with that system. Maybe I have the benefit of giant shoulders, but this seems like a…
It is not mundane, and it is also not right, at least for entropy in Physics and Thermodynamics.
> High-entropy states are those macrostates which have many corresponding microstates.
That is how you deduce entropy form a given model. But entropy is also something that we can get from experimental measurements. In this case, the experimental setup does not care about microstates and macrostates, it just has properties like enthalpy, heat capacity and temperature.
We can build models after the fact and say that e.g. the entropy of a given gas matches that predicted by our model for ideal gases, or that the entropy of a given solid matches what we know about vibrational entropy.
That’s how we say that e.g. hydrogen atoms are indistinguishable. It’s not that they become indistinguishable because we decide so. It’s because we can calculate entropy in both cases and reality does not match the model with distinguishable atoms.
> The classification of several microstates into the same macrostate, is this not a distinctly observer-centred function?
It seems that way if we consider only our neat models, but it fails to explain why experimental measurements of the entropy of a given materials are consistent and independent of whatever model the people doing the experiment were operating on. Fundamentally, entropy depends on the probability distribution, not the observer.