Fractional power of units of measures in F#

Question

Is it true to say that : there are no fractional power units in F#

Answer 1

In addition to what has already been said, the best resource for information about (not just) F# units of measure is Andrew Kennedy's PhD thesis, who actually designed F# units. He mentions fractional units:

The most important decision is whether or not to allow fractional exponents of dimensions. The argument against them is philosophical: a quantity with a dimension such as M^1/2 makes no sense physically, and if such a thing arose, it would suggest revision of the set of base dimensions rather than a re-evaluation of integral exponents. The argument in favour is pragmatic: sometimes it is easier to write program code which temporarily creates a value whose dimension has fractional exponents. In this dissertation the former view prevails, and fractional exponents are not considered. However, most of the theory would apply just the same; any potential differences are highlighted as they arise.

I think this is essentially the reason why F# does not have fractional units, because the F# design quite closely follows Andrew Kennedy's work to make sure it is sound.

Update: With F# 4.0, support for fractional exponents has been implemented