Yan Zhang

Youth corruptor. Mathematician. Father. The Fool. Player of Games.

[Yan Zhang @krzhang]

A "writing" page to archive my writing, including favorite tweets and eventually a thread index: https://t.co/FEY9eage2y

[Yan Zhang @krzhang]

An Attack on Content-based Chunking… (joint with Boris Alexeev and Colin Parcival):

HN: https://t.co/QI3xdlA4fo
Tarsnap webpage: https://t.co/LcU3e58gvA
Paper: https://t.co/3min00CGiW

[Yan Zhang @krzhang]

Addendum 1:

Confirmed. If I ask the question counting molecules of "magic dust" it consistently gets the right answer. If I ask it counting "water" it consistently (n=3) gets the wrong answer.

[Yan Zhang @krzhang]

.. which means there would be roughly 50 moles in a L, so we should get about 13 moles instead. Multiplying by Avogadro, I get 13 x 6 x 10^{23} ~ 8 x 10^{24} molecules per glass. Since the volume of ocean was 1.4 x 10^{21} L^3, the ocean is 5.6 x 10^{21} glasses.

4/

[Yan Zhang @krzhang]

So shouldn't that make 13 x Avagadros [sic] constant more like 8 x 10^24? That would be off by 10 again...

Current state: I'll assume Schrodinger meant "1000" until someone corrects me. Still confused at how AI had the same answer as Schrodinger at first...

9/END

[Yan Zhang @krzhang]

@AskYatharth fr

[Yan Zhang @krzhang]

In "What is Life," Schrodinger claims that if you could mark the molecules in a glass of water; then spread them uniformly into the oceans and sample a new glass, you would find about 100 of your marked molecules.

This exercise, somehow, turned into frustration at Society...

1/

[Yan Zhang @krzhang]

This gives 12 * 6500^2 (km)^2 * 4km * 2/3 ~ 1.2 x 10^{18} m^3.

(sanity check: https://t.co/FDAZ9gmPo7 gives 1.4 x 10^{18} m^3, so we're doing fine so far!)

Now a glass is about 250 mL (1/4 of a L, makes sense). How many molecules are in it? Well, H2O has 1+1+16 = 18 g/L,

3/

[Yan Zhang @krzhang]

For estimation, we can assume the Earth is a sphere. I'll assume known that its radius is r = 4000 mi ~ 6500 km (which is itself a good exercise). I know that the ocean is about 4000m deep and 2/3 of the 4\pi r^2 surface area is ocean, and of course, for us, \pi = 3, so...

2/

[Yan Zhang @krzhang]

... In the Deserts of the West, still today, there are Tattered Ruins of that Empire, represented by Animals and Beggars, but no Disciples of Voting Theory."

(mostly stolen from "On Exactitude in Science", Jose Luis Borges)

3/3

[Yan Zhang @krzhang]

On Representative Democracy in Voting

"In that Empire, the Art of Voting Theory attained such Perfection that the number of representatives of a single Province occupied the entirety of a City, and the number of representatives of the Empire, the entirety of a Province...

1/3

[Yan Zhang @krzhang]

... In time, these Unrepresentative Voting Systems were no longer satisfactory. The Voting Theory Guilds struck a voting system of the Empire who votes for a set of representatives whose size was that of the Empire, and every person was represented by exactly one person...

2/3

[Yan Zhang @krzhang]

Good luck @kanjun!

[Kanjun 🐙 @kanjun]

I'm excited to share our $200M Series B at a $1B+ valuation to develop AI systems that reason!

We believe reasoning is the main blocker to effective AI agents. We train large models tailor-made for reasoning on our ~10K GPU cluster. On top, we prototype agents we use every day.

[Yan Zhang @krzhang]

@razibkhan Thanks! I’m interested in the *degree* of residual Mongolian influence, mostly because I’m Chinese (There’s a way in which the Yuan dynasty is both important and ephemeral in Chinese history). Do you have more thoughts on how deep the residual effects are, esp. compared to China?

[Yan Zhang @krzhang]

@karlrohe @tszzl I’m guessing IC = “intellectual contributor”. There’s a sense that at e.g. a tech company, an IC would look down on others (like managers) for being not technical enough.

[Yan Zhang @krzhang]

@exGenesis @bluesky Fair winds

[Yan Zhang @krzhang]

@levs57 @aard_k_vark We’ll take a look. Thanks!