Application of the EWL protocol to decision problems with imperfect recall

We demonstrate implementations of the Eisert-Wilkens-Lewenstein scheme be- yond normal-form games. The scope of our research includes decision problems, i.e., one-player extensive games. The research is based on the examination of their features when the decision problems are carried out via the EWL protocol. We prove that unitary operators can be adapted to play the role of strategies in deci- sion problems with imperfect recall. Furthermore, we prove that unitary operators provide the decision maker possibilities that are inaccessible for classical strategies.