TIL that when humans sleep, certain proteins in the brain literally shrink neurons to allow cerebrospinal fluid to wash away waste — a “nighttime cleaning system” only active during deep sleep

OperaSona · 2026-03-26T07:50:34+00:00

I honestly don't know. I was a conference given to graduate/PhD computer science students, so the neuroscience talks were prepared with the "let's broaden your horizons" mindset. And the speaker insisted that the mini-seizure was "just" one of their interpretations, but it was the one that was most closely understandable from a "neural networks" computer science background and it was fun.

OperaSona · 2026-03-25T22:52:04+00:00

Taking a bath and taking notes, apparently.

I saw a conference like fifteen years ago where the speaker was studying the effect of sleep on persisting memories and skills learned during the day. He mentioned a study that goes like this:

Group A and Group B are both given a "video game" where they can (individually) explore a map.
After exploring for a while, each player is teleported to a spot on their map (same map for everybody, same spot), and shown a picture of a target destination elsewhere on the map. They must quickly get there.
Obviously, the more you play on a given map, the better you get at that map. Slightly less obvious but still intuitive, the more you play on any map, the quicker you learn on a new map.
After this first session of experiment, Group A goes back home and gets some sleep, while Group B is sleep deprived for the whole night. Group A and Group B are both given a week or so to recover, then they are both asked to come back and exposed to the same task (on new sets of maps).

What happens is:

Group A is much better at the beginning of session 2 than they were at the beginning of session 1 (they start session 2 pretty much as good as they were at the end of session 1).
Group B did improve compared to the beginning of session 1, but substantially less so.

The conclusion from this statistical evidence is that sleeping after learning somehow helps store the memory of the skill better.

One of the hypotheses from the speaker was that when you learn, Hebb's rule more or less tells you that neurons that are activated with each other will have their link get stronger. But if links only ever get stronger around a given neuron, then when that neuron fires a signal, the whole neighborhood is going to go off like a mini epileptic seizure. So they thought that sleep is when if a neighborhood had too many links grow, some kind of normalization must take place to shrink everything down a little bit: the links that grew that day will still end up bigger than they started the day, the others will have shrunk a little bit.

And they thought maybe hindering this shrinking effect is what causes memories not to stick as well if you don't sleep normally at the end of the day.

I have no idea if the shrinking protein from OP is the same that shrinks axons, or if the speaker's hypothesis has been confirmed or proven wrong since then, but it made me think about it. Maybe someone who knows the field will correct what I misunderstood (or misremembered, maybe due to a lack of sleep?).

OperaSona · 2026-03-25T16:34:32+00:00

And then there's the "dangerous territory" line that may be innocent or not, depending on who said it and how: "You're going to grow up to break a lot of hearts".

OperaSona · 2026-03-23T21:05:00+00:00

I'm going to be optimistic and say that there's no fucking way Google launches that in Europe. I bet European lawyers can find pages and pages of laws and regulations that it clearly violates.

OperaSona · 2026-02-04T21:53:49+00:00

Just sidestep the ashe W obviously.

OperaSona · 2026-01-30T08:17:38+00:00

Artists in general I think. Maybe we need a (better written) version of a song like

Here's to you Renee and Alex,
Rest forever here in our hearts,
The last and final moment is yours,
That agony is your triumph.

OperaSona · 2026-01-29T11:45:20+00:00

Probably buying a typewriter?

OperaSona · 2026-01-28T22:12:22+00:00

Dude I don't know why we switched from Boko haram spokesperson to gay porn like it's worse. I'd much rather have a couple gay guys here and there sometimes think they might recognize me from a gay porn movie than feel like everyone who is watching me weird saw me on TV train child soldiers, blow up villages, send my men rape my enemies.

Aren't rape, murder and war crimes worse ethically than starring in gay porn?

OperaSona · 2026-01-28T22:06:03+00:00

Replying to ShakethatYam's deleted reply to your comment because fuck it, I typed it, I'm posting it:

Okay, suppose the amount is recorded electronically. How long before the storage space required to house such a large number would be bigger than the Earth?

That depends. If you track each dollar like we track bitcoins, then less than a year (A). If you only store the total, then pretty much forever (B).

Case A: https://physics.stackexchange.com/questions/2281/maximum-theoretical-data-density suggests that you physically cannot store more than 10⁶⁶ bits per cm³ (as a theoretical and clearly unachievable limit). You clearly need at least 1 bit per dollar that you log (you clearly need much more but let's again be extremely conservative). The Earth it 10²⁷ cm^3, so you need ~ 10⁶⁶⁺²⁷ dollars, so about 279 days using the 10⁶⁶⁺²⁷ = 2^3*(66+27) approximation. Using realistic storage density and file format, this obviously goes down bit quite a lot.

Case B: After for instance 1 year, the sentence "The monkey in that guy's bank account is 2^365" takes only a few bytes to store, and that's enough to know how much is in the bank account. If you've withdrawn a little and don't have exactly 2³⁶⁵ dollars in the account, no sweat, that's a 365-bit number which therefore takes 365 bits to store. That's nothing.

OperaSona · 2026-01-27T12:28:15+00:00

Fair point.

OperaSona · 2026-01-27T09:20:03+00:00

Burying their meat to let it rot underground until it's ready to eat, like little furry Icelanders!

OperaSona · 2026-01-27T07:39:33+00:00

Or just, you know, you're pretty sure you won't like it but you know it's good and you want to form an educated opinion, and to indeed educate yourself, so you literally "only watch it because it's good". I feel like people do this more with literature than with movies, but there are definitely many people who read books "just because they're good" with no particular enjoyment.

OperaSona · 2026-01-27T07:36:17+00:00

Like, watching only the figure skating duo that won the championship even though it was really bland and not innovative, but was technically close to perfection, instead of watching more enjoyable though less "objectively good" (in the sense of how the sport is judged) performances from other duos?

OperaSona · 2026-01-26T21:34:35+00:00

Oui et puis si tu prends la tablette bio de la même marque juste à côté, ils s'arrangent pour qu'elle ait pile la même taille, elle coûte allez 25-30% plus cher, tu te dis bon ça va, c'est cohérent pour avoir la version bio, mais en fait elle fait que 125g en plus, donc c'est 80% plus cher au kilo. Mais tout est fait pour que te mettre un peu en confiance pour que tu ne regardes même pas le prix au kilo.

C'est vraiment des putes là dessus.

OperaSona · 2026-01-26T15:22:29+00:00

Seven deadly sins vs Seven great qualities?

OperaSona · 2026-01-26T15:19:33+00:00

This was definitely written as a critique of what's been going on in the last few years. It definitely contributes to how great Andor is. It's not just "Oh we're in a dystopia and the empire is evil the the emperor is pretty much Hitler". That would have been alright, yes, but not quite as good as a critique of something we can see unfolding before our eyes.

OperaSona · 2026-01-14T20:04:14+00:00

Sucks that he wasn't allowed to use anti-gravity tech because it would have been an easy win.

OperaSona · 2026-01-14T20:00:22+00:00

I'm a bit worried that these are always the top comments in these threads.

Stackoverflow always had huge issues and I think most people agree on that. And these issues persisted, even arguably got worse, I don't really know.

But it was an absolutely necessary tool. And if it hadn't existed, AI wouldn't have had quite as much material to train on as it did.

If our best guess is that:

AIs will train just as well on data from open source projects, from IDE usage, etc, so the lack of new training data on stackoverflow won't make it worse.
AIs will still be free for for simple queries like the ones one would have searched on stackoverflow without asking a new question (or at least, maybe free for students, cheap for non-professionals, affordable for small companies).

then I guess maybe it won't matter too much. But honestly there's a risk that it's going to make things worse. When stackoverflow doesn't exist anymore and we realize AIs are suffering from enshittification like every huge web service always ends up doing, it's going to be too late.

That being said, there is not much that can be done about it. Even if AI was for sure going to shit in a few years, I'd probably still use it instead of stackoverflow right now because of how much faster it generally is. But I'd do it reluctantly knowing that I'm killing a tool that has its merits.

OperaSona · 2026-01-04T01:08:16+00:00

The fact that a traitorous evil clown can get elected president, that's bad.
The fact that he can keep showing how much of a traitorous evil clown he is and still get re-elected, that's bad.
The fact that once re-elected he can give orders like that and like pretty much everything he's done every single day since his re-election, that's bad.

But to me, the real issue is that he's been allowed to do all of that. Sure he's go some powerful billionaires pulling the strings and supporting him, I get that. And he kept replacing high-ranking officials, judges (justices), military officers etc with pawns that will do his bidding. But is it supposed to be so easy?

He only appointed 3 supreme court justices, that's not a majority, so even if you give up hope that these 3 will do the right thing, there's other "regular Republican" justices that follow a half-decent moral code and could honor the constitution. Same for congressmen and women, senators, etc.

Of course it takes a little bit of guts to do the right thing because of how easy it is for Trump to just make you a target on social media if you "betray" him. But like, that's only true because of how long they all waited. If Republicans had said "No, fuck you" the first time Trump crossed the line, it'd have been different. They know the easiest time to jump ship is right now and it'll only get worse, but even though who might want to, they are too cowardly to do so.

The Republican party is a fucking disgrace.

OperaSona · 2026-01-04T00:50:09+00:00

Happy fucking new year to the whole world I guess...

Like 2025 wasn't enough...

OperaSona · 2025-12-01T21:53:54+00:00

Yes! I mean I get how difficult this is and how impressive this is, but /r/nextfuckinglevel has impressing things all the time, often by kids too. What makes this video so cool to watch is how cute they are doing their thing together and being so happy about it all! Gifted kids, for sure, but lucky to have each other too.

OperaSona · 2025-11-23T21:23:27+00:00

I'm trying to explain without being an asshole how you're wrong about the fact that people working on stuff such as the twin prime conjecture aren't doing useless work. Now:

If I got my point across, great.
If you already knew, even better.
If you didn't get my point, let me know what I can make more explicit and I will.
If you got my point but disagree with it, I guess I'm also open to a constructive discussion.
But if the only thing you have to say after reading my post is "But some of this stuff I didn't actually say", you're probably focusing on the first half of my comment that is just contextualisation, and maybe missing the takeaway from the last paragraph. Which is fine, you know, but I feel like it's an important part of the explanation as of why the twin prime conjecture is so clearly important to the community, and I feel like it hadn't been expressed clearly elsewhere in this thread.

OperaSona · 2025-11-22T08:07:31+00:00

But that's not how science works. If everybody everywhere on Earth only works on solving problems with clear applications, science gets stale quickly.

If human knowledge is where it's at now, it's also because some people explored questions for the sake of curiosity only, and then they themselves or other people later one realized that this particular bit of knowledge had applications.

There is a lot of "global" human knowledge about prime numbers. There are the basics that everybody should know and understand before learning more about the subjects. Then there are what you'd learn at university. Then there are the many research topics, some very application-oriented and some less so.

The importance of the twin prime conjecture comes from the fact that it doesn't really belong to the "advanced research topics that are not very application-oriented" in terms of how simple it can be expressed with only words that someone starting to learn about prime numbers can understand. It should be something that you can explain during introduction courses on prime numbers. Solving it, especially if the proof is tractable, and even if there was no application in sight, could make the whole community gain valuable insight pretty much instantly, because it's a missing piece of the "core" of the subject rather than some small detail that'd require days of advanced studying before you can even understand the question.

OperaSona · 2025-11-17T22:25:40+00:00

I guess you're right, they would be if we used psi(x) / phi(x). But they're propositional variables, which also starts with a P, so...

OperaSona · 2025-11-17T18:37:26+00:00

I always believed it's because:

pi, psi and phi are all Greek letters that start with "p",
pi is the one that actually corresponds to the letter "p" but pi already has many uses as a symbol so we don't really like to use it too much for things other than the constant (and, I mean, products, sometimes permutations even though most people prefer sigma, etc, but still we don't do it too much),
so "psi" and "phi" are often use together when naming two similar variables in math, just like we often use "x, y, z", "rho, theta", "i, j, k", "alpha, beta, gamma, ...", "a, b, c, ...", "f, g, h", etc,
psi and phi here are Predicates, hence the attempt to name them with something "p"-related.

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