Equilibrium and the Dentist in Poughkeepsie

When we try to pick out anything by itself, we find it hitched to everything else in the universe.

– John Muir, Scottish-born American naturalist and writer

When we think of the word “equilibrium,” a whole range of meanings may come to mind

“Supply equals demand.” (market clearing)
“All deficits and surpluses add to zero.” (accounting identity)
“Things are temporarily stable, with no impetus to change.” (steady state)
“Every action has an equal and opposite reaction” (Newton’s Third Law)
“Nature keeps perfect books. What changes on one side is balanced on the other. Every change in spin, charge, and momentum in one place is exactly accounted for elsewhere, so the totals never change.” (Law of conservation)
“Nothing is lost, nothing is created, everything is transformed. (Lavoisier’s maxim)

The word “equilibrium” is an invitation to recognize that nothing exists by itself, alone. Subject and object are two sides of the same coin – their interaction is a single phenomenon.

Even at the tiniest level of the universe, if we look at the polarization of two entangled photons, the spin of two electrons, or the state of two qubits in a quantum computer, we find that measuring one immediately determines the correlated outcome for the other, even far away, without sending any signal. While there’s no theoretical limit to entanglement, the record distance measured to date was between two entangled photons – separated by 747 miles – which is kinda cool.

All of this may seem very abstract, but we can see that the workings of “equilibrium” pervade even the most ordinary aspects of daily life.

At the most basic level, for example, we realize that there’s no such thing as a buyer putting cash “into” the market without a seller taking that same cash “out of” the market. Every share someone just bought is a share someone else just sold (or issued). The buyer, the seller, and the exchange are inseparable – their interaction is a single phenomenon. Talking about “cash going into the market” is like talking about the sound of one hand clapping.

This month, we’ll examine a whole range of examples involving equilibrium, all of which are directly relevant to current economic and market conditions. First, we’ll review the strikingly lopsided equilibrium that’s emerged across various sectors of the economy. This equilibrium helps to understand the record level of corporate profits in recent years – although the distribution of corporate profits is more closely related to whatever innovations and industries are dominant at any particular point in time.

Next, we’ll examine equilibrium in the securities markets – why prices fluctuate, what “flows” actually mean, and how fundamentals, information, and investor beliefs collaborate to determine prices and trading volume.