This was my first thought on seeing the title. Complex numbers are just vectors with special behavior for some operations, right?
I haven't read through the paper, but this statement from the abstract confuses me:
> Here we investigate whether complex numbers are actually needed in the quantum formalism. We show this to be case by proving that real and complex Hilbert-space formulations of quantum theory make different predictions in network scenarios comprising independent states and measurements.
Maybe I'm interpreting "real numbers" and "need" differently than the authors, since in my head complex numbers are basically just a structure containing two real numbers and some modified behavior.
I haven't read through the paper, but this statement from the abstract confuses me:
> Here we investigate whether complex numbers are actually needed in the quantum formalism. We show this to be case by proving that real and complex Hilbert-space formulations of quantum theory make different predictions in network scenarios comprising independent states and measurements.
Maybe I'm interpreting "real numbers" and "need" differently than the authors, since in my head complex numbers are basically just a structure containing two real numbers and some modified behavior.