What allowed two knot diagrams to represent the same mathematical knot?

Answer

Continuous deformation via Reidemeister moves

In the topological framework used by modern knot theory, two knot diagrams are considered mathematically identical if one can be transformed into the other through a specific set of allowable manipulations. These crucial manipulations are formally known as Reidemeister moves. These moves represent the fundamental ways a knot diagram can be altered continuously in space without introducing tears or gluing new connections. Recognizing that a sequence of these moves connects two diagrams confirms they belong to the same equivalence class, signifying they represent the same underlying mathematical knot structure, regardless of how complex or differently drawn the initial diagrams might appear.

What allowed two knot diagrams to represent the same mathematical knot?
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