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Comment by eigenket | Hacker News Reader

I don't understand where you think that happened in this article?

The point is that hypothetically there is a way to make an extremal black hole, if you had essentially god-like powers. None of the authors are shocked or in disbelief that about this actually being possible.

In general mathematicians fall into two rough categories. Some are pure mathematicians who are happy doing their theoretical stuff and don't care whatsoever about what happens in reality. Others are more applied, and are usually very explicit about how and where their work matches and diverges from reality.

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At least the way it’s described in the Quanta article, it seems like the mathematicians assumed a charged scalar field, which is not something that exists in nature. All charged particles are associated with spinor (spin 1/2) or vector (spin 1) fields. A scalar field corresponds to particles of spin 0 - the only scalar field we know of is the Higgs field, and corresponding Higgs particle is not charged. If god-like powers include a way to change the laws of physics, then your take holds up, but proving something is possible if the laws of physics were different is not very interesting.

They did their calculations with a charged scalar field essentially because this stuff is really difficult, and you want to make life as simple as you possibly can. I think there are no obvious obstructions to it working with the electron field, it's just that it would be much more involved to actually calculate everything.

Probably someday someone will do it, but I don't think it's an incredibly interesting thing to do.

So, if you have two spin (1/2) particles together, this can overall act like either a particle with spin 1 or a particle with spin 0, right?

While 4 spin (1/2) particles could either act like a particle with spin 2, or like a particle with spin 1 (in one of three different ways) or like a particle with spin 0 (5 + 3*3 + 1 = 2^4 ) right?

So, what if we consider helium-4 nuclei in the spin 0 state?

Maybe that doesn’t make sense..

> theoretical stuff and don't care whatsoever about what happens in reality.

Just an aside: I think this is an oft-repeated misconception. It’s not so much that pure mathematicians ‘don’t care about reality’ — it’s more that they consider the mathematics itself to be reality already. If mathematics isn’t reality, I’m not sure what is.

As soon as you’re doing any kind of ‘modelling’, it would be reasonable to say it’s no longer ‘pure’ mathematics. Of course, the divide between pure and applied is somewhat fuzzy.

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