Does Roshar have its own gemheart?

[Ripheus23]

Either the continent or the planet, I mean. (I was toying with a theory that the continent is some kind of ultra-greatshell, and that the highstorms pass when this animal swims across the Origin, but if this were true I think it would be hard for people to sail beyond the continental coastline and remain properly oriented towards their own origins, so to speak.)

I partly hope this idea turns out partly true, at least, since I'd love to see a scene where the whole world lights up with Stormlight.

[RShara she/her]

That'd be pretty hilarious! But no, probably not For one, I think it'd be way too Terry Pratchetty, there'd definitely be some rough feelings about that. For another, there are actual islands that aren't greatshells, like Thaylenah, and Aimia, and and a bunch of smaller ones. And yeah, as you mentioned, ships would have a pretty hard time sailing around if the landmass were always moving. You can also watch how the continent was formed if you google "julia set," as that's what Brandon based the shape of the continent on.

It's a fun idea though

[Gray to he/him]

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(regarding Roshar's shape resembling a storm)

Brandon: I was searching for something that at once felt organic, but would hint at a pattern. (Much like cymatic patterns, as referenced in the first book.) Fractals and mathematical functions became my go-to place to hunt, as I like the blend of structure and spontaneity they can sometimes exhibit. The slice of the Julia Set was the one that stuck with me as feeling perfect for Roshar. As the continent was specifically grown by Adonalsium, you now know the seed that was used in-world to create it.
The fact that it looked like a swirling cloud is part of this all--but also part of the connection between natural patterns and the underlying math, which is a primary theme of the Stormlight books. So yes, it SHOULD look like a storm--but for deeper reasons than you might assume.

It would make a lot of sense if there was a gemheart in the core of the planet that Adonalsium put there and infused it with so much stormlight that it created life...

Ok maybe it doesn't make sense but it sounds cool.

[Okdes he/him]

The fact the Reshi Isle and other islands exist make this impossible. They would have wildly different locations based on time of year, being totally on accessable for large portions of it. Besides, sailors would notice that their continent has flippers and isn't ever where they left it. 

[Xtafa]

I'd say not, I can't find the WoB but gemhearts as it is are formed due to leaking investiture from the Cognitive realm. I imagine a giant gemheart core would be more akin to a perpendicular. 

 

But then again, I wouldn't be surprised either.

[Brightshade the Cunning]

In addition to the challenges posed by other islands, we already know that there are small islands that are greatshells from WoR. So the size differential would suggest that these smaller islands would be slower and fall behind, in the same way that larger animals tend to be faster, yet they remain in the same relative location on the planet. You could argue that the continent would be slower, but I find that unlikely.

[Calderis he/him]

The Taina are the biggest that greatshells get. 

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Questioner

Are there any greatshells in Roshar's oceans larger than the ones we've seen?

Brandon Sanderson

No.

Questioner

So the Reshi Isles--

Brandon Sanderson

The Reshi Isles, that's the biggest, and even with that I'm doing major fudging on the square-cube law. They've just spren-bonded, we'll talk about this. But even with the spren, those are a stretch. That's as big as it gets. They could exist in the oceans because the square-cube law doesn't apply the in same way, with buoyancy and things. But I think we don't need anything larger than islands.

Questioner

No Godzilla?

Brandon Sanderson

They're bigger than some version of Godzilla.

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