Predominantly Erroneous (Exohedron nonsense blog)

Oh wow, that is interesting.

I have said and written “knock on wood” many a time after mentioning an unpleasant thing that hasn’t happened, even in tweets with the character limit, and I do actually knock on wood every time. If I’m tweeting outside I often use the nearest tree. My friend from the Republic of Georgia will kinda spit over her shoulder three times, though it’s more like making a “puh” noise three times because no one wants to clean up spit. I don’t consider myself superstitious and I wouldn’t say she is either, but I guess there’s probably some psychological value. Especially if two cultures do basically the same thing in different ways to handle the issue of trying not to spend too much time or energy on imagining awful things.

 

Girl
Girl help my wife

 

Back in grad school I had a discussion with a friend about how much value we can assign to judgments of movies made by people who haven't actually seen the movie.
Thinking back on it now, I think I've softened my position on the matter, in the sense that everyone who judges a thing judges not the thing but rather the model of the thing that they hold in their head, and so the question is not a matter of whether you have or have not seen the movie, but rather how accurate a model of the movie do you have. You generally expect that actually seeing the movie improves the accuracy of the model, but depending on what criteria you're judging by, you might not need a very accurate or a very precise model to make a valuable judgment.

 

Here's a cool article on the dynamics of traffic jams and how to deal with them.

 

New creature idea: looks like a dog, but when looking directly at it you perceive it without any saccadic masking.

 

That sounds terrible. I love it.

 

At work there was an attempt made at playing rock-paper-scissors on the whiteboard.
The problems with playing rock-paper-scissors on the whiteboard should have been:

- It's asynchronous: people post their moves whenever they have free time to wander past the whiteboard, which means one player gets to see the other player's move before making their own
- It's anonymous: no one is actually sure who is playing, so anyone can post a move if they feel like it.

The usual game on the whiteboard is chess, for which the asynchronity is fine because chess is turn-based, and people used the honor system with regards to who was actually playing. For rock-paper-scissors, not so much.

Anyway, the actual problem with the attempt at rock-paper-scissors was after the first round (rock-rock), someone put up lizard as player 1's move, and after that the set of possible moves was just whatever anyone felt like.

The game was ended (by erasing the entire board) after round 4, which if I recall correctly was scissors-defect.

 

I won't have to worry about people guessing the ending of the sci-fi story I am never getting around to writing, because it doesn't really end, it just stops. There are a bunch of dangling threads but I like the place where I plan to cut it off.
But Exo, you might exclaim, what about all of the unresolved, imminent existential threats to the protagonists? Aren't you going to say anything about how they deal with any of those? And I will just shrug and reply that that's what fanfiction is for.

 

Modular representation theory is a nightmare.

 

Spoiler: Spoilers for the hypothetical sci-fi story

The ending is like if the person who has been helping you to fight against the evil empire has just put you on the throne of said empire and handed you all of its tools and weapons, but she doesn't really care about that. She just needed to break the line of imperial succession in order to remove a curse on her people, but she doesn't really care about that either. The value of removing the curse for her is that she personally is now functionally invincible and immortal, but she doesn't really care about that either. She really just wants to be alive to witness the upcoming apocalypse.

 

When someone tells you "this is how this dish is made back in my home country," and then someone else retorts "it is if you're from the south. The real way to make it is like this" and they get into an argument in their native tongue and you can't follow any of it, and you've only ever had the version you get in restaurants in the US anyway.

 

Clear blue sky out of one window, thunder out of the other.

 

But yeah, my stubborn refusal to learn commutative algebra is coming back to haunt me, as I always knew it would.

 

I always hear Tom Lehrer in his song New Math explaining, “because addition is commutative,” as if he’s just explained everything, whenever I hear that word in any math context. The joke almost always works.

 

A while back, when Google Plus was still a thing, I made a post about how I didn't like how category theorists would say that a category and its opposite have the same objects. That, to me, was clearly the worst way of saying there was a correspondence between them. I got some responses saying that I was worrying too much and that it was a convenience that would only lead to minor confusion at most.

And now one of the people who made such a response is trying to learn topos theory and is running straight face-into-the-glass into the issue that a functor between sites induces two different morphisms pointing in opposite directions and they're both the "obviously" the direct image induced by that functor, because sheaf theory is a contravariant nightmare and of course you're going to have this kind of nonsense if you don't distinguish between C and C^op!

This is the kind of thing you learn the hard way in commutative algebra or representation theory or functional analysis: objects are not their duals.

Anyway, I was going to clarify for him that the nlab is similarly confused about which morphism is the direct image, but then I remembered that post and now I know that I wouldn't be able to refrain from rubbing it in his face if I tried to help.

 

Minor confusion my ass. Notation and its rules are how people generally tend to understand and interact with the underlying math? I think most of us really like to be able to trust that if we follow the rules of the notation, the corresponding math will be valid. Why anyone would imagine that it wouldn’t be a problem if they decided to try not respecting that, entirely on purpose, is a mystery to me.

Sounds sorta like a programmer who thinks they’re too 1337 to need to comment their code or use helpful variable names. Congratulations, you created a logic error! Not even a regular one, which is bad enough. You knowingly built an inaccuracy into your own idea of what the logic even looks like. Sounds fun!

 

I know they're called barbers or hairdressers, or even stylists if you're feeling fancy, but hear me out: locksmith

 

Occasionally I wonder what I'd be like if I were religious, instead of having been raised by 1): a strident atheist and 2): someone whose religious beliefs I still don't actually know for sure, but has never said a single word in any direction so I guess functionally atheist? Maybe?
Wow, what a thing to realize about one's parent at this age.

 

Reading a conversation my dad is having about solving quadratic polynomials, I'm realizing that years of math and cryptography experience have trained me to think of taking square roots as easy and factoring integers as hard, so all the dithering about avoiding the quadratic formula is so unintuitive.

 

When there's a track you liked a bunch of years ago that you've only ever heard in DJ mixes so you have no idea what it's actually called, and looking up the lyrics makes you suspicious that the version you heard was an unlicensed bootleg remix and that's why you can't find it on Beatport.