Meaning of Butterfly Effect

Butterfly Effect in chaos theory.
What is the Butterfly Effect?

What is the Butterfly Effect:

The Butterfly Effect is an expression used in Chaos Theory to refer to one of the most striking characteristics of chaotic systems: sensitivity in initial conditions.

This phenomenon was first detected and described by the American meteorologist Edward Lorenz when he was working on a system of differential equations in order to model the evolution of the weather (climate).

The sensitivity phenomenon in relation to small disturbances in the initial conditions was described through an allegory, dubbed the Butterfly Effect, according to which the flapping of a butterfly's wings in Brazil can trigger a sequence of meteorological phenomena that will cause a tornado in Texas. 

The expression also had the happy coincidence that the "attractor" studied by Lorenz in his system of equations has a geometric shape similar to a butterfly.

Movie The Butterfly Effect

This scientific phenomenon served as inspiration for the plot of a 2004 American film, The Butterfly Effect, written and directed by Eric Bress, J. Mackye Gruber.

In the plot, a young man develops the supernatural ability to, based on his memories, make small changes in his past that determine new directions in the course of his life.

Subsequently, the films Effect Butterfly 2 (2006) and 3 (2009) were released, which were not as successful as the first.