The concept of equilibrium (temporary?)


That is Carmela Uranga.


Even at "equilibrium" in a simple molecule which is theoretically separated from all other interactions, the locations of many things inside it are a matter of probabiltiy.

At the level of a more complex system, even in a dynamic equilbirium in which the average can be pinpointed with very high accuracy at even fairly short periods of time, the constituent parts might have characteristics which vary significantly over time. In the economic and social analogies, things like path dependence might become quite important.

It's obviously a "stack-elberg" equilibrium...

Carmela is driving me crazy, she has some urangutang moves!

It is saddle point equilibrium. Stable in the vertical directions but unstable in the horizontal directions where small perturbation will destroy it. Like the case b in

Tyler read all of those books in three days.

more likely he read them in three hours

Consider an ideal gas in a cylinder. Pressure and temperature will never equilibrate; the temperature will be higher and the pressure lower at the top (higher altitude/lower gravimetric potential).[assuming we have instruments sensitive enough to measure the differences.] Turns out that the common conception of "equilibrium" is a figment of our imagination; there is no such thing. While I don't dispute a place for the Law of Large Numbers in our models of real systems, I question our use of "equilibrium" models; chances are high that requiring the existence of equilibria (as contrasted with steady-states) won't lead to any fundamental understanding of real world systems. Is this just another way of saying "In the long-run, we'll all be dead."?

One could argue that in the dynamic equilibrium inside that system, particles shift and move about within essentially constant average conditions at each location in the chamber. So, there is equilibrium in the statistical sense of average conditions remaining the same (e.g., same higher temperature at top, same higher pressure at bottom), while still being dynamic in the sense of stuff moving around.

it's not clear to me whether there is substance to disagreement on the matter or whether it's quibbling over definitions. Classic physics would suggest that at equilibrium there is stasis. However, with newer knowledge, I think it is more appropriate to consider a system as being at equilibrium if conditions are constant. Once you start getting into quantum and sub-atomic or electromagnetic stuff, if you reject this notion of equilibrium then one must reject the possibility of equilibrium at all.

So in the economics case, you have average conditions, an average trajectory, etc. But, there are still lots of ups and downs and non-average results among constituent parts (people, businesses, whatever level of economic analysis you are interested in), while at the Newtonian macro level one might argue that there is some equilibrium, or that some growth trend reflects an equilibrium of sorts.

Anyways, my view is that the notional concept of equilibrium generally applies, but it is incorrect to say "we are at equilibrium". Rather, in a context of ever-changing conditions, there is always a trend towards equilibrium, in the absence of some forces (e.g., cartels, monopolies, regulations, anti-trust enforcement, etc.) which intentionally try to subvert conditions so that the new politico-economic equilibrium is different, and hence the trend can move towards some different and new equilibrium. But surely conditions will change again long before equilibrium is actually achieved.

How that can be made practical for CGE models or other means of forecasting without turning us all into robot-like guinea pigs who serve an AI-facilitated overlord is an altogether different question.

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