robryk @robryk@qoto.org
I enjoy things around information theory (and data compression), complexity theory (and cryptography), read hard scifi, currently work on weird ML (we'll see how it goes), am somewhat literal minded and have approximate knowledge of random things. I like when statements have truth values, and when things can be described simply (which is not exactly the same as shortly) and yet have interesting properties.
I live in the largest city of Switzerland (and yet have cow and sheep pastures and a swimmable lake within a few hundred meters of my place :)). I speak Polish, English, German, and can understand simple Swiss German and French.
If in doubt, please err on the side of being direct with me. I very much appreciate when people tell me that I'm being inaccurate. I think that satisfying people's curiosity is the most important thing I could be doing (and usually enjoy doing it). I am normally terse in my writing and would appreciate requests to verbosify.
I appreciate it if my grammar or style is corrected (in any of the languages I use here).
Joined Nov 2020
robryk
boosted
Our electronics educational segment for today: U.S. Army Restricted Training Film: "Vacuum Tubes (The Triode)": 1943. - https://www.youtube.com/watch?v=acGXBJv6AT4
Rereading a novel I got amused by:
> Wanaka’s rather grim smile could just be made out behind her mask. “Until we get a better idea,” she
gestured. “All hands, start thinking.”
robryk
boosted
#NixOS on the @PINE64 #PinePhonePro .
There are still alot of steps to take, but it will get there.
Hm~ thought experiment: how would the world look like if trademarks could only be owned by corporations[1] with a responsibility only towards upholding the trademark's reputation[2]?
[1] question of ownership unresolved (theoretically it should be immaterial)
[2] question of who has standing to argue that they're not fulfilling this duty also open
robryk
boosted
the sad reality of open source software development
In short: folks love the amazing decentralised encrypted comms utopia of Matrix. But organisations also love that they can use it without having to pay anyone to develop or maintain it. This is completely unsustainable, and Element is now literally unable to fund the entirety of the Matrix Foundation on behalf of everyone else - and has had to lay off some of the folks working on the core team as a result.
https://matrix.org/blog/2022/12/25/the-matrix-holiday-update-2022
We define the rank of a matrix as the minimal number of rank-1 (i.e. of the form w^\dagger{}v) matrices that sum to it. I wonder what happens when we decide to optimize for something else: say, norm of type $foo over norms of type $bar over those matrices. Obvious candidates for $foo are L_{something}, for $bar are operator norms or Frobenius norm.
In particular, $foo=L_n and $bar=operator norm inherited from L_n seems potentially interesting (in particular for n=2).
Ok, it seems to have the the old-and-well-known preponderance to just pull numbers and multiply them without regard for what they are: https://you.com/search?q=How+heavy+is+1l+of+air+at+10atm%3F&fromSearchBar=true&tbm=youchat
robryk
boosted
Question: Why has there been nearly 0 media coverage in the US about Enovid and other nasal sprays?
"Most significantly, it showed, specifically for a higher risk population, that a negative PCR was achieved on Day 4 (median) compared to Day 8 for placebo."
That's really good?!
The chatbot-style answers of https://you.com seem impressive.
If asked nonsensical questions, they provide nonsensical answers. However, contrary to chatgpt, when asked very weird but sensible questions or fact lookup questions, it does provide correct answers (also, doesn't refuse to answer questions on fake grounds).
How do client blacklists work with gdpr?
Why do PKP IC (https://www.pkp.pl/) and Blik (https://blik.com/en) put people under time pressure when performing transactions? They teach people to click stuff without reading (and probably also lose some part of ability to claim that customers really know the terms of service, given that they make them impossible to read in the timeframe).
robryk
boosted
I figured out why the #fediverse clicks with so many GenXers. It's "yesterday's tomorrow!"
That is, it's the decentralized networked future we imagined as kids, complete with the billionaire baddies, evil corps, and environmental degradation plot lines all playing at the edge of the screen.
robryk
boosted
Speaking of Zener breakdown, here's a classic #electronics brainteaser. Find a generic small-signal bipolar transistor, e.g. 2N3904, 2N2222. Connect Emitter to +12 V via 1 kΩ, and ground Base. You can then find a negative voltage around -0.4 V relative to ground at Collector. Why can it be negative, when there's no negative voltage anywhere in this circuit?
When the base-emitter junction experiences Zener breakdown, it emits red light, which shines upon the base-collector junction. Photovoltaic effect creates this negative voltage. https://www.youtube.com/watch?v=bKlbO5mOZm4
When you don't realize that you've bought disks with quite high vibrations at seek time:
(The doohickeys are from https://www.thingiverse.com/thing:1774380. All in all works surprisingly well; apparently ~all the audible seek noise was coming via the case due to impedance matching.)
@lauren Why do most (all?) your posts include an all-white image?
robryk
boosted
Playing with GCP's Confidential Compute stuff, and I feel like the advice in the docs to verify that the VM has confidential compute enabled by (checks notes) asking the metadata service whether the instance has confidential compute enabled is maybe missing the point a little
robryk
boosted
@kwf So what can you do? Well, optical fibers happen to be excellent electrical isolators. Electric currents and magnetic fields go hand in hand. So instead of winding an electrical conductor around the transmission line, you wind some length of Faraday active optical fiber around, send polarized light through it and measure the amount of polarization rotation on the other end: That's an optical current transformer. https://en.wikipedia.org/wiki/Fiber-optic_current_sensor
robryk
boosted
When I held my notorious/legendary "Jay Ward Film Festival" at UCLA in the early 80s (attended by Bill Scott, June Foray, and more!), Bill (the voice of Bullwinkle and so many more familiar voices) told a story of would-be "censorship" on "Rocky and His Friends" (1959-1964).
Seems that they had done a sequence where Rocky and Bullwinkle are in a pot being cooked by natives. The sponsor went nuts. "You can't have cannibalism on a kids' show!" the sponsor proclaimed.
The reply: "Is it really cannibalism to cook a moose and a squirrel?"
The bit stayed in.
I have an audio recording of the entire proceeding, including a live performance and amazingly prescient Q&A session. I really need to get it back online.
robryk
boosted
has anyone seen a really good guide to writing good code reviews? someone just asked me and I couldn't think of anything
I enjoy things around information theory (and data compression), complexity theory (and cryptography), read hard scifi, currently work on weird ML (we'll see how it goes), am somewhat literal minded and have approximate knowledge of random things. I like when statements have truth values, and when things can be described simply (which is not exactly the same as shortly) and yet have interesting properties.
I live in the largest city of Switzerland (and yet have cow and sheep pastures and a swimmable lake within a few hundred meters of my place :)). I speak Polish, English, German, and can understand simple Swiss German and French.
If in doubt, please err on the side of being direct with me. I very much appreciate when people tell me that I'm being inaccurate. I think that satisfying people's curiosity is the most important thing I could be doing (and usually enjoy doing it). I am normally terse in my writing and would appreciate requests to verbosify.
I appreciate it if my grammar or style is corrected (in any of the languages I use here).
Joined Nov 2020
