What we have achieved so far is not entirely satisfactory: Supersymmetry (more precisely, the broader framework of supergravity) offers a partial solution to the weak-scale hierarchy problem. Partial refers to the fact that SUSY partners have not been discovered (yet?) and hence some fine-tuning is probably needed after all. Supergravity is needed to combine this with general relativity, but it does not help with the cosmological constant problem, which unavoidably shows up in this context. Technically, the cosmological constant can be anything in supergravity: It can be negative due to the − 3|W|2 term, or positive due to a dominant |DW|2 term (with SUSY spontaneously broken). It is also affected by UV divergences since (in spite of the non-renormalisation theorems for W), the Kahler potential K is loop corrected. Moreover, the UV problems of gravity (all operators being generated at the scale M P—i.e. formal ‘non-renormalisability’) are not resolved by the prefix ‘super’.
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