Scientists use surface area to volume ratio as a tool to calculate all sorts of physical realities, from the vagaries of cell biology to environmental concerns such as food packaging. This simple concept is useful in describing the problems that have arisin from our increasingly lopsided economy.
The surface-area-to-volume ratio also called the surface-to-volume ratio and variously denoted sa/vol or SA:V, is the amount of surface area per unit volume of an object or collection of objects. The surface-area-to-volume ratio is measured in units of inverse distance. A cube with sides of length a will have a surface area of 6a2 and a volume of a3. The surface to volume ratio for a cube is thus shown as .
For a given shape, SA:V is inversely proportional to size. A cube 2 m on a side has a ratio of 3 m−1, half that of a cube 1 m on a side. On the converse, preserving SA:V as size increases requires changing to a less compact shape.
This concept is simple enough for a child to understand; in fact, I just explained it with ease to my 12-year-old. It also serves as a marvelous analogy for income inequality. To wit, if a large percent of the wealth rests in the hands of a few, the economy will stagnate because each person can only consume a finite amount. $3000 sundaes aside, it's difficult to spend more than about a million dollars a year. Therefore, most wealthy people will put a substantial amount of money in savings. Each dollar saved in an economy is a dollar not used to pay a worker.
Paradoxically, wealthy people are actually job killers because they sit on money. People are fooled into thinking CEOs are "job creators" because they get to utter the magic words "you're hired!" (and of course, "you're fired," if not usually with such glee as Donald Trump). But the real job creators are consumers. And the lower the SA:V, the fewer widgets (and services) will be purchased. That means fewer jobs...which is the only economic statistic that matters to voters.