# Random walk

Different spaces for a random walk include the one-dimensional space of integers (e.g. successively flipping a coin with values of $\pm 1$ and adding these up or the Fermi estimation), the plane with real coordinates (e.g. the drunkard's walk), or 3D euclidean space (e.g. Levy Flight or the Wiener process). More uncommon spaces include graphs (see the overview here) or groups in the mathematical sense (a short introduction can be found here).
For a polymer chain undergoing a completely ramdom walk the end-to-end length $R$ scales with the number of segments $N$ like
$R \propto \sqrt{N}$