Determining the Future

The French mathematician Pierre-Simon Laplace suggested an intellectual being (demon) that knows the position and motion state of every particle in the Universe, and every forces that acts on them, that being is able to predict the future and make change to it.

While theoretically possible, it cannot be done to do so because it is impossible for anyone to know with absolutely precision of the properties of every interacting atoms.

In 1886, the Sweden King offered a prize of 2500 kroner to anyone that can prove or disprove the stability of the solar systems.  In other words, will the planets remain their orbits or one of them may crash into the Sun or drifted out of the system eventually.  The French mathematician Henri Pancare tried to analyze the problem with just 3 bodies - the sun, the earth and the moon.  Pancare found that even with only 3 objects, the equations are mathematically impossible to resolve because of the sensitivity to the initial conditions.  The calculations showed complete irregularity and unpredictable result.  Pancare nonetheless won the prize.

There are the billiard game software widely available these days.  While it is possible to simulate the interaction of balls on the table, it is impossible to predict in reality.  To predict, one must know the position and movement of the white ball.  One must also know the position and movement of all other balls, and the friction of every strain of fiber on the table cloths which affect the friction, and the size and shape of every dust on the table that could steer the ball off course for a minute immeasurable amount etc.

Edward Lorenz is a mathematician and meteorologist in America.  In early 1960, Lorenz used a LGP-30 desktop computer to run a weather simulations.   At one point, he wanted to continue a simulation half way by re-entering intermediate calculated numbers from a print out.  Unexpected, the result of the simulation is different from the lat runs.  The reason was the computer calculate using 6 decimal points but the printout only contains 3 decimal points.  Lorenz noticed that the minute difference can make a big impact to the simulation result.  He coined the term butterfly effect to describe the rippling effect which based on the 1952 novel by Ray Bradbury.