Many-body problem

The many-body problem involves understanding how a large number of particles—such as electrons, atoms, or molecules—interact with each other through forces like gravity or electromagnetism. Because each particle's behavior affects and is affected by all others, predicting the system's overall behavior becomes extremely complex. This challenge appears in areas like physics, chemistry, and materials science. While simple two-particle systems can be solved exactly, adding more particles increases complexity exponentially, often requiring advanced computer simulations and approximation methods to analyze and understand the collective behavior of the system.