Simple homotopy theory

Simple homotopy theory is a branch of algebraic topology that provides a way to study the properties of topological spaces through the lens of homotopy equivalence. It is particularly concerned with the study of CW complexes and involves a concept known as simple homotopy equivalence. ### Key Concepts 1. **Homotopy**: In general, homotopy is a relation between continuous functions, where two functions are considered equivalent if one can be transformed into the other through continuous deformation.