Is there such a thing as a perpendicularity to the spiritual realm?

[The Elemental Shard]

If so does the well of ascension fit this?

[Weltall]

Perpendicularities already allow transition between any of the Realms. Khriss discusses it in the Arcanum Unbounded essays and Dalinar notes it when he opens Honor's Perpendicularity. There's also this WoB:

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Oversleep

Could you use perpendicularities to see into Spiritual Realm?

Brandon Sanderson

Yes.

Skyward Pre-Release AMA (Oct. 4, 2018)

 

Edited June 24, 2019 by Weltall

[RShara she/her]

Perpendicularities are concentrations of investiture intense enough to pierce all three Realms. So yeah, by definition, a perpendicularity allows access to the Physical, Cognitive, and Spiritual.

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TheFulgid

Could you Invest... Could you use a nicrosil metalmind to Invest the sort of Investiture enough that you could open a Perpendicularity up to the Cognitive Realm?

Brandon Sanderson

So, I'll just say it this way. Enough concentrated Investiture in one point is going to pierce the Realms, no matter what form it takes. 

TheFulgid

...So, it doesn't have to be a nicrosil metalmind.

Brandon Sanderson

No. 

TheFulgid

Okay... But it could be?

Brandon Sanderson

Yes. That is theoretically possible. 

Oathbringer release party (Nov. 13, 2017)

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Questioner

In our universe, mass and energy curve space. I was wondering if Investiture does the same or something similar

Brandon Sanderson

It does something similar. It draws the three Realms together. So it's got like-- Imagine a gravitational pull piercing Realms. Right? Of kind of--

Questioner

And that's how a perpendicularity works?

Brandon Sanderson

That's not the only way a perpendicularity works, but one surefire way to create a perpendicularity is a massive collection of Investiture in the Cognitive or mostly Physical realm. But Cognitive's weird, doesn't always work the right way. But there are ways to do it that way too.

Salt Lake City signing (Dec. 16, 2017)