keenanpepper

joined 1 year ago
[–] keenanpepper@sopuli.xyz 8 points 11 months ago

I got a grant to do independent research on the AI alignment problem and was able to quit my job.

[–] keenanpepper@sopuli.xyz 7 points 1 year ago (3 children)

Yeah Thinkpads are obviously a popular suggestion here. I'd check out System76 too (their cheapest stuff may or may not fit your definition of "cheap").

[–] keenanpepper@sopuli.xyz 2 points 1 year ago (1 children)

Cooking in a cast iron pan will give you even more iron.

[–] keenanpepper@sopuli.xyz 4 points 1 year ago (1 children)

https://mathoverflow.net/questions/142205/presentation-of-the-monster-group mentions a presentation of the monster with 12 generators.

Creating a physical rotation puzzle that implements the monster group would be quite a task!

[–] keenanpepper@sopuli.xyz 12 points 1 year ago (3 children)

I know exactly one party trick based on mathematical group theory, which I have actually used to impress non-mathematicians at a party.

There's a concept called the "center" of a "group", which is the set of operations that commute with every other operation in the group. The center always contains the identity operation of doing nothing. The group of scramblings of a Rubik's cube happens to contain exactly two elements in its center: the identity, and a move called the "superflip" which takes a little bit of effort to memorize how to do, but it's not so hard. Much easier than actually solving a scrambled Rubik's cube. It's like you do a simple move repeated 4x, and then you do that whole 4x set 3x with some rotations in between. Not terribly complicated. Importantly, once you memorize it it's not difficult to do just by feel, since it's a fixed sequence of mechanical motions.

So, the party trick goes like this:

You have a Rubik's cube that is exactly a superflip away from the solved state. You hand it to an unsuspecting party guest and say "go ahead and make one or two turns" (it's important to say something like "one or two" because if they do 3 the trick becomes challenging, and if they do 4 or more it might become impossibly difficult unless you're actually good at solving Rubik's cubes, which I am not). They take this obviously unsolved cube and make a couple more moves so now it appears even more scrambled.

You take the cube back and do the superflip behind your back, without looking at the cube.

Then you move the cube out from behind your back, and at the same time (trying to be slick about it) you undo the one or two moves remaining before it is solved. Everyone gasps and say "omg he solved it behind his back" (when really you did no such thing).

This works because if S is the superflip and X is the simple moves they did to it, S X S is equal to just X because S commutes with everything. (S is also its own inverse, so that S S = 1.)

[–] keenanpepper@sopuli.xyz 7 points 1 year ago

One thing that definitely feels like "magic" is Monstrous Moonshine (https://en.wikipedia.org/wiki/Monstrous_moonshine) and stuff related to the j-invariant e.g. the fact that exp(pi*sqrt(163)) is so close to an integer (https://en.wikipedia.org/wiki/Heegner_number#Almost_integers_and_Ramanujan.27s_constant). I hardly understand it at all but it seems mind-blowing to me, almost in a suspicious way.

[–] keenanpepper@sopuli.xyz 14 points 1 year ago (4 children)

Right. The farthest people have been is the Moon, which is still gravitationally bound to the Earth. Plenty of spacecraft have been out of Earth's gravity well, and also a car, but no humans.

[–] keenanpepper@sopuli.xyz 47 points 1 year ago (2 children)

Oh, the first time I read this I had a completely wrong idea what it was about. I thought it was talking about like the Dalai Lama having being reincarnated or something.

[–] keenanpepper@sopuli.xyz 6 points 1 year ago (1 children)

So just like a citrus fruit intermediate between lemon and lime?

[–] keenanpepper@sopuli.xyz 8 points 1 year ago (6 children)

Explain more... do you mean, just something exactly intermediate between octopus and ice cream in every respect? Or like, octopus with the flavor of ice cream, or texture of ice cream inside?

 

What mashups of food or drink would you try first?

[–] keenanpepper@sopuli.xyz 2 points 1 year ago

That's prudent.

[–] keenanpepper@sopuli.xyz 3 points 1 year ago

One time I ordered like a whole liter of silicone lube (to refill smaller containers from). I got this funny feeling from it being such a large amount of rare precious stuff, like it was a cask of fine whisky or something.

 

Hi, I hope this is the right place. I have successfully subscribed to some remote communities, but now whenever I view a remote community there's no "Subscribe" button I can click but instead just plain text saying "Subscribe", like the button is disabled or something.

Does anyone know why that's happening and what I should do to subscribe to more remote / federated communities?

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