Metal mind questions

[King Cole he/him]

I call upon the all knowing @Calderis / @Extesian

1. Does the size/shape of a metal mind influence how much can be stored?

2. What would happen if you filled a gold metal mind with health, then melted it down and changed its shape?

3. If you broke a metal mind in half, what would happen to the stored attribute?

Edited July 26, 2017 by King Cole

[+Extesian he/him]

I may not be Calderis, but

1. Size does, I think Sazed talked about a ring being full and Brandon has talked about metalminds being 'full'. I can't see that shape would?

2. Should be no difference by this

Quote

Q: What would happen if a Feruchemist fills, for example, a tin metalmind then mixes it to make a pewter metalmind? Does the stored attribute change? Is the Investiture gone when you melt the metal? What if he just makes it into a tin metalmind again?
 
A: If you make it impure, you'll keep the investiture, but won't be able to get it out. If you make it back into the same thing, you'll be fine, and can access it normally. If you try to fill it, after changing the composition to make another viable metal, it will act a little like a computer hard drive with corrupted sectors. Some of it will work for the new investiture, but you won't be able to fill it nearly as full. (Depending on how full it was before you melted it down.)
This holds for basic uses of the metallurgic arts. Once you start playing with some of the more advanced parts of the magic, you can achieve different results, which are currently RAFO.
 
Q: So you could, for example, use electrolysis to dissolve a metalmind in water, then reverse the reaction later to get the Investiture? Or, better question, if you store investiture in one allotrope of iron, can you retrieve it if you change to a different allotrope?
 
A: I see no reason why these wouldn't work.

3. Same as two i think

Edited July 26, 2017 by Extesian

[+hwiles He/Him]

11 hours ago, Yata said:

There is no clue in the text about the "form matters" for a Feruchemical charge context. The only tangential clue (the Medallion's Forms) seems to go aganist this...but it's real tangental as nobody except the Southerns and Rashek had really to bother about Metalmind's full capacity.

We know the amount of metal matter (it's really meaningless if te "mass" or the "volume" are the key factor, as the Metal's structure is setted by the Magic System and the two parameters are bound one to another without too margin.

Sanderson's descriptions of feruchemy indicate that Investiture is stored in the crystal structure of the metal, with different types of feruchemic charge fitting into different crystal structures (IE: different metals).  It's also stated that breaking a small piece off of a metalmind will result in a small metalmind with a portion of the original metalmind's Investiture, meaning that feruchemic charge stored in a metalmind flows and spreads out to fill the entire space available to it, much like any type of charge.

The maximum density of a charge distribution is, in part, dependent on the shape of its vessel.  The extreme example is 1-dimensional, 2-dimensional, and 3-dimensional atomic structures, which, for a specific number of atoms, give very different amounts of space in which charges can be inserted and "stored."  Consider the following:

Given 6 atoms of metal, a 1D arrangement gives space for 5 charges, and a 2D arrangement gives space for 7.  Potential storage density can be roughly gauged by relating a shape's surface area to its volume; spheres give the greatest potential density, and a thin/spiky objects give the least.  The effect is significant in electric charge because electrons repel eachother.  Since feruchemic charges also spread out from each other to fill their entire available space, rather than clump together or fill the space randomly, I assume that they too repel each other to some extent.  The repulsive force between same-type feruchemic charges may be extremely high, or negligibly small; there's just no way of knowing at this point, though I suspect that, for the sake of simplicity, it's probably very small.  This means that shape should only have a relatively small influence on a metalminds potential storage capacity.

But all other considerations and speculation as to the physics of feruchemic charge aside, shape really should have some effect on storage capacity just from the basic nature of how the charge gets stored and the fundamental geometry of the situation.

(Bear in mind, this is a highly simplified description of charge; the specifics are much more complicated, but also outside the scope of the original question)

Edited July 27, 2017 by hwiles

[King Cole he/him]

7 minutes ago, Extesian said:

3. Same as two i think

But what if you didn't put them back together?

[+Extesian he/him]

6 minutes ago, King Cole said:

But what if you didn't put them back together?

Sorry I was in the process of adding a couple of WoBs. Here's one on point

Quote

Maru Nui ()

What happens when you break a Hemalurgic spike or metalmind? What happens to that power?

Brandon Sanderson

Hemalurgic power can be split among multiple spikes and reforged, but remember that the longer a spike is outside of a person, the more the power is going to decay. Things like splitting it will decay it even further. Metalminds can also be broken and still be accessed.

And here's the one I was looking for on metalminds having limits

Quote

When I was developing this world, I knew I wanted the Keepers to have the fantastic memories. I realized that Feruchemy would make the perfect magic system for Sazed and his people. When I decided that I could use metals as a focus for this magic system (something that made it much more interesting, because it put a definable limit on what could be stored and how much of it could be stored) I knew I had something really good.

I've seen nothing on shape though

Edited July 26, 2017 by Extesian

[Calderis he/him]

@Extesian covered it all pretty well. 

As far as "shape" is concerned, it shouldn't have any bearing whatsoever. All that should matter is the total volume of the metal to determine capacity. 

[+hwiles He/Him]

@Calderis , @Extesian , I actually disagree with you on the shape issue. The way Investiture flows through and gets distributed in a metalmind or spike is, in many ways, similar to how electric charge gets distributed in a conductive solid. I believe that the scenes at the end of BoM where Alik uses a piece of etmetal to power what appear to be electric lights highlights this relationship best; meaning, it is the easiest to grasp without delving into electrodynamics. This could be coincidental, but my understanding of Sandersons style leads me to believe it is at least slightly deeper than that.

Basically, I believe that spherical metalminds should be able to hold charge more efficiently than very thin metalminds of equal mass and volume. This is because as Investiture gets poured into the metalmind, the thing that makes the metalmind "full" is a gradually building resistance caused by the reduction in degrees of freedom in movement of the Investiture already present. Like how blowing more air molecules into a balloon makes it gradually harder to blow up. If a metalmind was so thin as to be nearly 2 dimensional, all of the Investiture stored in it would lack an entire degree of freedom right off the bat; I won't bore readers with the math, but this would be a massive detriment to storage of any type of charge or digital information.

An alternative analogy would be solid state memory; 3d circuit boards can store fantastically more information than flat circuit boards of equal mass and volume.

Whether this is a significant enough effect in Cosmere physics to be meaningful remains to be seen, as the storage density of all metalminds that have appeared on screen thus far have been almost arbitrarily large. In era 4 however, if compounding, ftl travel, and advanced metallic arts based tech come into play, this ought to be a major consideration. Like how it didn't matter much in the early days of electricity irl, but now it's a huge limiting factor in manufacturing computer chips.

Tldr; Investiture seems to spread out in metalminds like electric charge and different shapes can hold different amounts of charge before they start to overflow. (See: dielectric breakdown)

I believe that, in general, thin pointy shapes shouldn't be able to hold as much feruchemic charge as thick round shapes. I leave the discussion of rolled feruchemic cylindrical "capacitors", advanced materials, and "semiconductive" metalminds to the true Cosmere scholars. Or for when I'm less exhausted...

For those who are interested, the way Investiture gets trapped in metalminds whose composition has been changed seems analogous to how charge acts in electric insulators, and Sandersons comments about "achieving different results" from altering metalminds with more advanced techniques implies to me that semiconductive metalminds should be possible; ie: metalminds that can be filled/tapped with 1 or more attributes, but only when certain temporary conditions are met. The process of making them, I believe, would be similar to "doping" techniques used in creating semiconductors irl; in its simplest form, doping involves placing specifically spaced impurities in a crystal structure to increase electrical resistance in only one direction through a solid. I believe a similar result ought to be possible for metalminds. The application for this tech would be to allow computers and machines to transfer/store/manipulate feruchemic/hemalurgic charges.

I hesitate to delve deeper for the moment as this is highly, highly, highly speculative.

Edited July 26, 2017 by hwiles

[Yata he/him]

There is no clue in the text about the "form matters" for a Feruchemical charge context. The only tangential clue (the Medallion's Forms) seems to go aganist this...but it's real tangental as nobody except the Southerns and Rashek had really to bother about Metalmind's full capacity.

We know the amount of metal matter (it's really meaningless if te "mass" or the "volume" are the key factor, as the Metal's structure is setted by the Magic System and the two parameters are bound one to another without too margin.