I would like start a sentence with "From the point of view of information theory, ...", but this sounds a bit uneloquent to me. Can I say, "From an information theoretical point of view, ...", or would that be wrong, too? What would be a good way to say this?
You could also use the near-synonym perspective:
Are all valid. Perspective has the minor advantage that "point of view" can mean both a way of looking at something, and also an individual opinion, which a field clearly can't have. (A minor advantage only, because it's the sort of semi-ambiguity that can't cause any real confusion, just perhaps break some readers' flow).
I would though say that "information theoretical" reads a bit strangely to me, but that's out of context, and opining strongly on which is or isn't inelegant is pointless without the full sentence, because how each of these flows (or doesn't) with the rest will affect its euphony.