Imaginary numbers could be needed to describe reality
Imaginary numbers are what you get when you take the square root of a negative number. When you add imaginary numbers and real numbers, the two form complex numbers, which enable physicists to write out quantum equations in simple terms. But whether quantum theory needs these mathematical chimeras or just uses them as convenient shortcuts has long been controversial.
Even the founders of quantum mechanics thought the implications of having complex numbers in their equations was disquieting. Erwin Schrödinger – the first person to introduce complex numbers into quantum theory – wrote, “What is unpleasant here, and indeed directly to be objected to, is the use of complex numbers.” Schrödinger did find ways to express his equation with only real numbers alongside an additional set of rules for how to use the equation.
But now, two studies have proven him wrong. They show if quantum mechanics is correct, imaginary numbers are a necessary part of the mathematics of our universe.