Scientists have explained what the three-body problem is

After the release of the movie The Three Body Problem, based on Liu Sising's famous novel series, on Netflix, we have seen many people asking what exactly the Three Body Problem is. So join us on a journey into the physics and mathematics that began at the very beginning of modern science and continue to trouble scientists and thinkers today.

Newton's laws of motion and his law of universal gravitation were the basis of classical physics and could explain the behavior of a wide range of phenomena. In particular, with their help, you can easily describe the movement of the planets around the star - these are tasks of two bodies, a star and its planet or the Earth and the Moon.

These two-body problems can be solved with an accuracy that gives great predictive power. Knowing the initial conditions, we can predict how the system will evolve in the future. Now let's add the third body. You might think it would add some difficulty, but it would still be solvable, but reality seems to have a wicked sense of humor. The two-body problem is completely solvable, but the three-body problem is not.

There is no generalized solution that allows predicting the behavior of three objects (or particles, or planets) according to the laws of motion and force. Solutions can be found for specific cases and some not-so-specific cases, but there is no way to solve the three-body problem for all possible cases.

Initially, the question of the three-body problem (and then the n-body) concerned the stability of the Earth-Moon-Sun system and the Solar System as a whole. The search for solutions led to new mathematical tools, such as perturbation theory, to improve the numerical solution found for the motion of planetary bodies.

It also led to the prediction of Trojan asteroids orbiting Jupiter by the Italian-born mathematician Joseph-Louis Lagrange, who was studying a special case of the three-body problem.

Although the three-body problem using Newtonian gravity is considered traditional, it is also solved in quantum mechanics. A helium atom with a positive nucleus orbiting two negative electrons is also an example of a three-body problem.

And if you like gravity but would rather make your life hell, why not try to find a solution to the three-body problem using general relativity? This comes in handy near black holes.

New solutions to specific three-body problems are found every few years. And you never know if you'll need it to make sense of a mysterious, hyper-realistic video game...