A method to madness: The mathematical basis for the butterfly effect

In the blockbuster hit “Jurassic Park,” fan-favorite Jeff Goldblum stars as the eccentric Ian Malcolm. As a critic of the magnificent park, Malcolm often claims that nature is best in its most primal form, untouched, as even small artificial changes can have dire consequences. This notion is known as the butterfly effect, a small piece of a branch of mathematics known as chaos theory. The butterfly effect essentially proves that if a butterfly flaps its wings in one part of the world, it will ultimately cause a tornado elsewhere.

The butterfly effect was not coined until about 50 years ago, when MIT professor Edward Lorenz decided to truncate and round one of his variables in a weather simulation. This small change, where he rounded from millionths to thousandths, led to an unexpected result in his weather simulation. With this knowledge, Lorenz concluded in his paper “Deterministic Nonperiodic Flow” that not only do small changes in nature have unpredictable effects, but also that it is impossible to predict the future. This is where the idea of chaos theory was born, paving the way for more research on the forces and laws that make up the Earth, all the while breaking the rules of classical physics.

In this paper, Lorenz focused on breaking down the idea of chaos theory and the butterfly effect through the logic of mathematics. Lorenz’s idea was to show that in imperfect systems, such as the atmosphere, “such procedures involve replacing the continuous variables by a new finite set of functions of time.” This means that variables will constantly need to be changed, mirroring the actual world and universe. He concluded that in nonperiodic, or chaotic, scenarios, it would take an incredible number of computations to logically map out what the universe can do in seconds. So while a butterfly’s flapping wings will cause a tornado, it is not humanly possible to figure out when, where, or how.

He concluded that in nonperiodic, or chaotic, scenarios, it would take an incredible number of computations to logically map out what the universe can do in seconds.

Lorenz’s work broke down much of Pierre Laplace’s idea of an orderly universe where all possibilities lead to unique, single outcomes. Laplace’s work “A Philosophical Essay on Probabilities” states that “we ought then to regard the present state of the universe as the effect of its anterior state and as the cause of the one which is to follow.” Laplace essentially explains that the universe is a result of cause and effect; what happened in the past created the present, and if humans are able to map out what happens in the present, they can easily predict the future. Laplace describes the universe as very straightforward, methodical, and periodic. However, Lorenz counters this by explaining that “prediction of the sufficiently distant future is impossible by any method, unless the present conditions are known exactly.” This, as aforementioned, is not humanly possible because of the sheer number of variables and calculations. Laplace’s work does not account for the idea that all butterflies do not act the same way: they each have their own number of flaps at different points in time.

Moreover, Lorenz’s work proves what Ian Malcom said in “Jurassic Park”: nature is best at its most primal form. Nature is stable when chaotic. One of Lorenz’s findings is that “all solutions, and in particular the periodic solutions, are found to be unstable.” This proves that a perfect system cannot exist in nature because it is unstable; imperfection is what is best. Trying to change the flap of a butterfly’s wings in order to prevent a natural disaster will paradoxically bring about more disasters.

Nature is stable when chaotic.

Lorenz’s findings of the butterfly effect led to more than just a deeper involvement in chaos theory. They proved that nature should remain untouched, and disturbing the “peace” of chaos will only cause harm. This is vital, as humans have been changing nature in major ways such as the Industrial Revolution, poaching and hunting, and now, increasing greenhouse gas emissions. Based on Lorenz’s work, if a single butterfly’s wing flapping can cause a tornado, it is horrifying to imagine what the destruction of a forest, a rise in global temperatures, and the death of a species can have in the long run.

J. Atmos. Sci. (1963). DOI: 10.1175/1520-0469(1963)020<0130:DNF>2.0.CO;2 

The Mathematical Gazette (1812). DOI: 10.2307/3608971