[BreakfastB0b]

This PBS Space Time video does a good job of explaining it https://youtu.be/1Z5fnwUmTSY. tl;dr the inner and outer event horizons of spinning black hole cancel out leaving a naked (ring) singularity which is believed to be prevented by the “Cosmic Censorship Hypothesis”. In the math it causes the event horizon radius to become complex which is believed to be “unphysical”. However maybe not, many “unphysical” mathematical objects have later turned out to be real such as black holes themselves (Einstein thought they were just a mathematical artefact) and anti matter (a result of negative roots of the Dirac Equation). Complex numbers are also an intrinsic part of the way Quantum Mechanics works, so perhaps there are naked singularities.

[ace2358]

Correct me if I’m wrong, but the Schrödinger equation isn’t the only mathematical treatment of the stochastic nature of quantum phenomena.

I thought matrix mechanics was with real numbers and was mathematically equivalent. I also thought there were different statistical systems that included “negative” probabilities that can be used to describe wave packets without needing complex numbers.

I do agree that sometimes the maths leads you to a truth in reality. Though sometimes it doesn’t.

I’m not too familiar with QFT, does that require complex numbers?

[codeflo]

What do you mean by “require”? Complex numbers can be represented as a 2x2 matrix of real numbers (a scaled rotation around the origin), so transitively, that’s true for any equation involving complex numbers.

[BreakfastB0b]

I don’t remember exactly since it’s been a while since I read it, but in Scott Aaronson’s Book “Quantum Computing Since Democritus” which is about how physics informs what’s computable. He talks about how the behaviour of quantum mechanics follows fairly straightforwardly from considering how probability works with complex numbers / bloch spheres. You can’t properly reproduce Bell’s Inequality without them I think?

[ridgeguy]

Thanks for this. The subject is way out of my wheelhouse, but I enjoy clinging to the coattails of explorers of worlds I don't understand.