Four-Dimensional Manifold

A four-dimensional manifold is a mathematical space that locally resembles our familiar three-dimensional space but includes an additional dimension, making it four in total. Imagine a surface like the skin of a balloon (a two-dimensional manifold); similarly, a 3D world can be thought of as a 3D manifold. When extended into four dimensions, such structures help scientists understand complex concepts like spacetime in physics, where time is considered a fourth dimension alongside the three spatial ones. These manifolds provide a rigorous framework for studying spaces that are more complex than everyday three-dimensional space, yet still have a consistent structure everywhere.