> There aren't to my knowledge any CPUs with special instructions for complex numbers There are lots of processors out there besides CPUs. You could even desig

> There aren't to my knowledge any CPUs with special instructions for complex numbers There are lots of processors out there besides CPUs. You could even design a new processor or program an FPGA to do complex math. Fast Fourier transforms deal with imaginary math, for example. You can do those in a number of ways, including on a CPU or GPU, but it's not unheard of for companies to use either custom hardware or programmable hardware to meet performance needs.