The Ensemble of Parametric Oscillators Model of the Economy
Markets can be modeled as ensembles of parametric oscillators. The parametric oscillator model is the simplest model that is useful in understanding dynamic market prices. For non-physicist readers, you've made a parametric oscillator whenever you've pumped your legs on a swing to change your frequency of oscillation. If you've ever had somebody push you, then you've made an amplified parametric oscillator, which is equivalent to a market hooked up to a time-varying external money supply.
Supply can be modeled as an ensemble of oscillators, one for each person. The cumulative frequency distribution of the supply ensemble is equivalent to the aggregate supply available to a market within a window of time. Demand can be modeled as an ensemble of oscillators, one for each person. The cumulative frequency distribution of the demand ensemble is equivalent to the aggregate demand available to a market within a window of time. See here. Elasticity is a function of the fatness of the frequency distributions at the half-maximum to their peaks. The distributions will be poissonian in shape.
Both cumulative distribution functions can be parametrized in terms of the opportunity cost of any scarce resource within an economy, or in terms of a currency that does not vary fast with respect to other currencies within the size of the time window. (Doesn't that explain why we use currency rather than bartering?)
The "temperature" of these ensembles (i.e., the shape of the distribution for a given amount of capital when scarcity and size of the ensemble are fixed) will be a function of the capital available. Similarly, other changes in the cumulative frequency distributions of supply and demand will be a function of capital (energy), scarcity (volume), and the size of the ensemble (pressure). If the changes are made slowly with respect to the time windows within which the distributions are measured, then convexities in the function of frequency with respect to increasing capital, decreasing scarcity, and increasing ensemble size may be observed. Certain ranges of capital, scarcity, and size of the population will be characterized by certain types of structures. In other words, as capital, scarcity, and size of population are tuned through different ranges, spontaneously ordered structures for the allocation of capital and resources throughout the ensembles will emerge. Thus, the parametric oscillator model is consistent with a thermodynamics of institutional design.
Thermodynamics gives us no insight into how and when change will occur. But the parametric amplifier model also permits an insight into market dynamics. According to this model, the ensemble of supply oscillators couples nonlinearly to the ensemble of demand oscillators. Mathematically, the mechanism for coupling is analogous to a damping force on each ensemble that is, in part, a function of the frequency distribution for the other ensemble. In other words, the oscillations of the two ensembles don't simply add or subtract from one-another. They can multiply or divide one-another.
In practice, the coupling mechanism might be provided by anything that causes the frequencies of the ensembles to multiply rather than add, such as transactions costs or liquidity constraints that do not vary linearly with the quantity of goods exchanged. Study of models of the coupling mechanism will be one of the most fruitful areas of research for econometricians. For the coupling mechanism is not simply a function of the frequency of the supply and demand ensembles of the market in question. Rather, it is a function of the frequency distribution for any supply or demand ensemble with non-trivial cross-elasticity with the supply and demand ensembles for the market in question. The coupling mechanism, including the phenomenon of cross-elasticity, is the dynamic mechanism that describes how and when phase transitions will occur.
Note that variations in external money supply would be a source of capital to the supply or demand ensembles that should be considered separate from the coupling mechanism. Thus, an increase in external money supply might give rise to parametric amplification. Variations in external money supply add many complications to understanding the dynamics of parametric oscillators. Having a Taylor rule that describes how the external money supply varies in time makes the model easier to solve.
Parametric oscillators exhibit many interesting dynamics. One is the phenomenon of parametric resonance, whereby the ensembles may become synchronized in phase. Phase synchronization is an implicit or explicit characteristic observable in all markets. Another is the phenomenon of parametric instability. Price bubbles can form when the resonance peak (or peaks) are too high-frequency to be sustainable.
For the Hayekians out there, given constant resources and population, as capital is removed from the system, spontaneous symmetry breaking will result in new spontaneous ordering of capital, resources, and population within the market. In other words, holding two out of three of capital, resources, or population fixed, and minimizing the other variable will lead to more spontaneous order within society.
As an end note, the wave equation necessary to the parametic oscillator model will not apply over longer time scales. Wave equations are second-order in time. For very large time windows, dissipative forces will have more noticeable effects, and a heat equation (like the Schrodinger equation) will provide a better approximation of dynamics. The difference in observable dynamics at different time-scales is part of why microeconomics and macroeconomics are not readily joined in econometric theory.










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