Some of that material is a little difficult. How did you manage to read it all so fast? I'd like to hear what you found most interesting.

As for what I'm working on right now, probably seeing the sunrise tomorrow, but see also https://news.ycombinator.com/item?id=48807996

If so, what is wrong with you?

I didn't post my notes on HN; in fact, I didn't even post them on dernocua.github.io.

> These can presumably be removed, permitting traditional SPIF processing of raw foil by sliding the point over the foil; a better alternative might be...

I don't think it's closely related to 0-_-0's "folding" idea.

It's a pretty broad term, with a lot of possibilities, but generally I mean a machine which, given a design for a machine in the form of digital data, can build a working machine of that design without further human interaction. Some imperfect approximations of the idea already exist:

- living things such as bacteria, humans, and plants: DNA is digital, true, but it's an unsolved problem to design the DNA to make a plant grow into the shape of even a chair, much less a bicycle, a lathe, or a computer.

- 3-D printers such as RepRap: they generally can only produce very limited machines without further assembly, with only very limited palettes of materials, falling far short of being able to print a whole printer without human intervention.

- ordinary compilers such as GCC: though they have already had a significant economic impact, they require a feedstock of magnetic disks or erased Flash from which to manufacture their output program, which still leaves their users vulnerable to TSMC and Western Digital. Worse, the output program depends on a CPU to run, leaving the users vulnerable to Intel and Qualcomm.

:-)

Mostly I wanted a name that was short, easy to remember, and unique.

My current notes are in http://canonical.org/~kragen/sw/pavnotes2.git/

https://en.wikipedia.org/wiki/Aluminium_chloride says orl-rat LD₅₀ of AlCl₃ is 380mg/kg, which is 20.2% aluminum by weight, so that's 77mg/kg of soluble aluminum ions. If this toxicity is due to soluble aluminum ions (rather than, say, acidity), and rats and humans are about equally sensitive to aluminum toxicity, you'd need about 3.8g of aluminum to kill a 50kg human, the ionized equivalent of 1.42mℓ of aluminum metal (at 2.71g/cc). That's 1420cm² of 10μm aluminum foil completely dissolved in the food.

Presumably you would get significant toxic effects well before reaching the lethal dose, so it would be wise to avoid exposures larger than a few tens of cm² of aluminum foil completely dissolved in your food. So it seems like the concern at least passes the first smoke test of plausibility: the total amount of aluminum present in a "grilling packet" is at least sufficient to worry about.

(Fortunately, aluminum rapidly becomes inert in the body, so we don't have to be concerned about gradual poisoning the way we do with lead and arsenic.)

The crucial question, then, is how fast the foil corrodes under cooking conditions! If it corrodes (and migrates into the food) at a micron or more per hour, then this could be a serious concern. But, if the corrosion rate is more like microns per month or microns per year, the dose wouldn't be high enough to worry about.

The fact that https://en.wikipedia.org/wiki/Aluminium_toxicity redirects to https://en.wikipedia.org/wiki/Aluminium_toxicity_in_people_o... suggests that this is at least not a recognized concern.