Mathematical model explains marital breakups

From PhysOrg:

Journal_pone_0009881_g004 Most couples marry only after careful consideration and most are determined to make their marriage last, and a happy marriage is widely considered in Western societies to be important for overall happiness. Yet soaring divorce rates and break ups of de facto relationships across Europe and the U.S. show these plans and ideals are failing. Many scholars attribute the increasing rates of breakdown to economic forces and changes in sexual divisions of labor, but this does not fully explain the continuing rise in those rates. The research was carried out by José-Manuel Rey of the Department of Economic Analysis, at the Universidad Complutense in Madrid, and aimed to provide a mathematical model to explain rising rates of marital breakdown. Using the optimal control theory model, Rey developed an equation based on the “second thermodynamic law for sentimental interaction,” which states a relationship will disintegrate unless “energy” (effort) is fed into it.

The results of the mathematical analysis showed when both members of union are similar emotionally they have an “optimal effort policy,” which results in a happy, long-lasting relationship. The policy can break down if there is a tendency to reduce the effort because maintaining it causes discomfort, or because a lower degree of effort results in instability. Paradoxically, according to the second law model, a union everyone hopes will last forever is likely break up, a feature Rey calls the “failure paradox”.

More here.