What is the 3 Body Problem in physics? Is there a solution to it?

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I recently finished watching the 3 Body Problem on Netflix so this question came to mind. Can anyone explain (in simple terms) why the 3 body problem was deemed unsolvable even by the advanced alien race in the series? Even better, can anyone here simplify what the 3 Body Problem actually is in Physics? It really got my curiosity. Thanks! 🙂

In: Physics

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Anonymous 0 Comments

[https://en.wikipedia.org/wiki/Three-body_problem](https://en.wikipedia.org/wiki/Three-body_problem)

>In [physics](https://en.wikipedia.org/wiki/Physics) and [classical mechanics](https://en.wikipedia.org/wiki/Classical_mechanics), the **three-body problem** is the problem of taking the initial positions and velocities (or [momenta](https://en.wikipedia.org/wiki/Momentum)) of three point masses and solving for their subsequent motion according to [Newton’s laws of motion](https://en.wikipedia.org/wiki/Newton%27s_laws_of_motion) and [Newton’s law of universal gravitation](https://en.wikipedia.org/wiki/Newton%27s_law_of_universal_gravitation).[^([1])](https://en.wikipedia.org/wiki/Three-body_problem#cite_note-PrincetonCompanion-1) The three-body problem is a special case of the [n-body problem](https://en.wikipedia.org/wiki/N-body_problem). Unlike [two-body problems](https://en.wikipedia.org/wiki/Two-body_problem), no general [closed-form solution](https://en.wikipedia.org/wiki/Closed-form_solution) exists,[^([1])](https://en.wikipedia.org/wiki/Three-body_problem#cite_note-PrincetonCompanion-1) as the resulting [dynamical system](https://en.wikipedia.org/wiki/Dynamical_system) is [chaotic](https://en.wikipedia.org/wiki/Chaos_theory) for most [initial conditions](https://en.wikipedia.org/wiki/Initial_condition), and [numerical methods](https://en.wikipedia.org/wiki/Numerical_method) are generally required.

There is no general [closed-form solution](https://en.wikipedia.org/wiki/Closed-form_expression) to the three-body problem,[^([1])](https://en.wikipedia.org/wiki/Three-body_problem#cite_note-PrincetonCompanion-1) meaning there is no general solution that can be expressed in terms of a finite number of standard mathematical operations. Moreover, the motion of three bodies is generally non-repeating, except in special cases.

More history of it in the “n-body problem” page

[https://en.wikipedia.org/wiki/N-body_problem#History](https://en.wikipedia.org/wiki/N-body_problem#History)

There is an analytic solution but it’s not practical…

>That is, obtaining a value of meaningful precision requires so many terms that this solution is of little practical use. Indeed, in 1930, David Beloriszky calculated that if Sundman’s series were to be used for astronomical observations, then the computations would involve at least 10^(8,000,000) terms.

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