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Comment by pjz | Hacker News Reader

This stuck out to me too. Fractals teach us that infinite length can be fitted into finite area, so I'm dubious about this claim. Though I guess if we're in the realm of physics, the Planck constant determines a kind of minimum length, so the original statement may be true?

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Pendant here: the Planck constant is simply a convenient length for all things subatomic, like a hectare or a fortnight. No minimum whatsoever implied there. Many, many things are smaller than the Planck constant.

> the Planck constant is simply a convenient length

m^2 * kg / s

"Many, many things are smaller than the Planck constant."

Do we have a proof of that? Honest question. I know strings are often postulated to be smaller (by many orders of magnitude in some cases) but we are not yet particularly confident they exist. I'm not aware of us being reasonably confident that anything is smaller than Planck's size. ("Smaller than Planck's size" isn't even all that easy to define.)

Event horizon of a black hole is many times smaller for instance.

The mass of a blackhole determines the size of the event horizon.

To have an event horizon smaller than the planck constant, the mass have to be also small. While theoretically possible, i don't believe this has ever been considered possible in reality - see https://en.wikipedia.org/wiki/Kugelblitz_(astrophysics)

"Smaller" in what sense? Surely not diameter. There's a known formula that gives you the diameter as a function of the BH's mass.

You mean the Planck length (related to the Planck constant, the speed of light and the gravitational constant).

> Pendant here: the Planck constant is simply a convenient length...

You tipped your hand by misspelling "pedant."

Ideal fractals also don't exist. :-)

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