@article {2205.06261, archivePrefix = {arXiv}, eprint = {2205.06261}, primaryClass = {quant-ph}, author = {Zane M. Rossi and Isaac L. Chuang}, title = {Multivariable quantum signal processing (M-QSP): prophecies of the two-headed oracle}, year = {2022}, url = {http://arxiv.org/abs/2205.06261} }