Inverse Problems Have Inverse Complexity
In this paper we show that inverting problems of higher complexity is easier than inverting problems of lower complexity. While inverting Σpi3CNFSAT is known to be coNP-complete sideri for i=1 we prove that it remains coNP-complete for i=2 and is in P for all i⩾ 3. Relatedly, we show that inverting Σpi3DNFSAT is in P for all i⩾ 1.
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