reading-2024 #science

Chaos is a very interesting book. It's a condensed story of the people who saw something else in nature, a disorderly order, chaos, fractals, unpredictability.

Starting from atmospheric research and trying to predict the weather with earlier computers, going to mathematical formulations, biology, and physics. Scientists started seeing patterns that made no sense, small changes that could have a large impact. Surfaces that would split themselves when inspected closely, creating the impossibility of defining an average.

The book includes lots of names and characters that were crucial for the development of non linear dynamics, chaos, and fractals, but except few I already knew (Lorentz, Mandelbrot), they are hard to remember.

What the book gives is a glimpse at a universe we, as scientists, often try to think it does not exist. An unpredictable universe goes against the purpose of science itself.

Interestingly, what the book shows, is that even simple equations, simple rules to create numbers, can give raise to behaviors that can't be anticipated. From branching, to Lorenz attractors. They are not hard to model, but they just give patterns that are infinitely complex.

Turbulence is one of such examples. People tried to look at it from many different angles. But the emergence of turbulence is completely chaotic. It extracts energy from systems, we can see it manifesting in clouds and liquids, when we cook, or on planes' wings. But the structure of turbulence is infinitely complex. Vortexes of vortexes.

Animal populations follow the same patterns. Simple mathematical models of population growth can give rise to smooth increases or decreases. Until some threshold is crossed, and there is no stable solution. Population would jump between two stable numbers from one year to the next, until something else changes and then it'll jump between 3, 4 or more numbers, until it returns to a stable cycle.

Perhaps Chaos is not a quirk, but what dominates our world. We just live in time scales and act on distances where we can dominate nature in a way that chaos tends to sneak past. Or perhaps not, perhaps weather cycles, political patterns, evolution itself are dominated by equations that can't be modeled. Functions that have no average value. The average we see is destroyed when we zoom in or out.