The Constructal Law
I will be writing a lot more about this in the future because it’s so important.
The Constructal Law is a new law of physics (wha?!?!). Yes, a new law of physics, specifically about how the designs of physical objects evolve over time, including animate and inanimate things.
It’s really, really hard to grasp the full consequences of this idea, but let’s start.
The Constructal Law stated simply is something like: Physical structures that can evolve over time will evolve to make things flow through them more easily.
Another way of saying it is that things naturally tend to evolve into the shape of rivers, trees, and lungs. This is no accident.
Here is a picture of the brain, cut down the middle from front to back.
Notice the brown part labeled “cerebellum.” Cerebellum means “little brain.” It’s very interesting for many reasons, but note its shape. Why does it look like a tree? It’s “branches” are called “arbors,” meaning trees.
The reason it’s shaped like a tree, or river, is because that is a very effective shape for transporting a flow from a single point to a 3-dimensional space and vice versa.
Flows are everywhere. Water flows, air flows, heat flows, electricity flows (think about the shape of lightning), but other stuff flows too.
Stress flows through concrete, which is why cracks in concrete look like rivers. They are, rivers of stress, created by the evolution of the concrete to enable the flow of stress through it more easily.
Our bones have evolved to direct the flow of physical force through them efficiently, so it doesn’t get stuck anywhere and build up to a breaking point. Of course, strong enough forces at certain angles will break bones, and they’ll crack the same as concrete or rocks, in little rivers.
In some ways, this idea that “flow systems” evolve to all have more or less the same shape is the least interesting part of the Constructal Law, but that’s the basic idea, and what what’s flowing right now.
More to come.
If you’d like to investigate some more on your own, here’s a scientific article if you want to get your hands dirty. Also, the man who came up with the idea is named Adrian Bejan, and his latest book is called The Physics of Life (amazon).
