Duality of Discrete Topological Vector Spaces

For a field $\ef$, the discrete topological vector spaces over $\ \ef$ are essentially of the form $\ef^{\alpha}$ where $\alpha$ is an ordinal. With additional appropriate properties, they are isomorphic to $\ef^{(\beta)}$ where $\beta$ is again an ordinal. Finally, the categories of the vector spaces of the the first and the second type are equivalent.