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norrius

131 karma · joined June 11, 2015

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norrius··on What is it like to be a thermostat? (1996)
> But if I asked you, "Why is this stove burner on?" it would be entirely normal for you to answer, "I'm making tea."

This is a confusion specific to the English language, not consciousness in general. Some languages distinguish between the past-oriented cause-why and the future-oriented goal-why explicitly (e.g. Russian: почему vs зачем).

norrius··on How to see bright, vivid images in your mind’s eye (2016)
> I can rotate a die in my minds eye without actually seeing it. It's hard to explain.

I think I'm the same. It's as if I can imagine a geometry, but it doesn't have any texture or colour. It's not black, not grey, not brown... It's a shape in its pure form, maybe like a wireframe, without a physical manifestation.

However, I can imagine music and actually hear it. I had this a couple of times where I "replay" a song in a foreign language I've heard a long time ago, and this time I can parse out more lyrics than before. All inside my head.

norrius··on An intutive counterexample to the axiom of choice
What is the "smallest positive number" in the set {x | x in reals and 0 < x < 1}?
norrius··on Explaining Huffman’s Impossible Pyramid
Sure, if you want to allow non-flat, curved faces, this body is possible. I'd argue this is not in the spirit of the question, similar to the triangle statue mentioned in the article.
norrius··on HTTP Status 418 – I'm a teapot
I come from a country with rather _interesting_ views on what should be allowed online. 451 is used often enough that I've seen it in the wild more than once (and consider yourself lucky if you haven't encountered it...).
norrius··on The unreasonable effectiveness of just showing up everyday
I suspect this is more about giving that almost-boiling water more points where it can break tension and start forming bubbles. So it doesn't make the water reach 100° faster but makes it more visible.
norrius··on The Norway Problem
> Whenever an input accepts YAML you can actually pass in JSON there and it’ll be valid

...unless your parser strictly implements YAML 1.1, in which case you should be careful to add whitespace around commas (and a few other minor things). This is a valid JSON that some YAML parsers will have problems with:

    {"foo":"bar","\/":10e1}
The very first result Google gives me for "yaml parser" is https://yaml-online-parser.appspot.com, which breaks on the backslash-forward slash sequence.
norrius··on Periodic table of the web's APIs
Does size/shape[1] mean anything? Or is it my punishment for not using Chrome?

[1]: https://i.imgur.com/g8J28D8.jpg

norrius··on The sparrow with four sexes (2016)
Can someone explain what prevents birds of the same subtype from mating? The article mentions that the chromosome 2 cannot cross over in meiosis, but I just fail to understand the mechanics of the process and how that leads to disassortativity.
norrius··on Eric Schmidt has applied to become a citizen of Cyprus
> Getting a bank in most other countries is not hard at all and certainly not a "nightmare."

I don't know about "most" countries, but my American colleagues in Germany and Switzerland complained about the difficulty of doing anything related to finance (banks, brokers, taxes) because of their extra tax liability. I personally had to sign quite a few forms certifying that I am not a US citizen or a greencard holder or in any other way tax liable in the US, so it does seem to be a big deal.

norrius··on Transmit Radio Signals via Ethernet
I love how a (metaphorically) air-gapped system can be attacked (literally) through the air. Maybe the truly critical things should also be vacuum-gapped (and put into Faraday cages while we're at it)?..

But the system still has some connection to the outside world, right? That means we could run some heavy GPU load and measure the variation in its power consumption, which apparently has been tried before: https://www.helpnetsecurity.com/2018/04/13/data-exfiltration...

Along these lines, the excess heat has to go somewhere, so maybe one could measure the variation in the work of the coolant system. I couldn't find any research about it right away (BitWhisper is similar, but a bit different), but I trust someone has already tried that.

norrius··on All Python versions less than 3.6 are now EOL
> So it broke the experience for all first time users.

To be fair, Python 3 provides a very clear error message if you try to use print as a statement, although I don't know when exactly that was added:

    $ echo 'print "Hello World"' > test.py && python3 test.py
      File "test.py", line 1
        print "Hello World"
                          ^
    SyntaxError: Missing parentheses in call to 'print'. Did you mean print("Hello World")?
norrius··on [dead]
I think the choice of an object in this comparison is interesting, altough it doesn't affect the result that much, of course. The 5-franc coin is ridiculously big: measuring 31.45 mm (1.24 inch) in diameter and weighing 13.2 g, it's one of the largest circulating coins in the world.
norrius··on The Recursive Universe
That reminds me of a story where a student couldn't figure out the properties of some physical system, so he ran a massive simulation of a universe with laws of physics similar to his own (but, of course, cutting corners whenever possible). This universe eventually produced a life form intelligent enough to figure out the necessary equations, at which point he happily copied them to his homework and forgot about the simulation.

...only to find it days later (= billions of years of simulated time), by which point the simulated life had figured out that their universe was written hastily and its laws were full of subtle bugs, like floating-point rounding errors showing up in physical measurements. Their technological advance let them move stars around, which they grumpily arranged in a message saying "your code sucks".

Can't find it at the moment, does anyone recognise the reference? It could be in one of these books, I suppose, but I don't have them.

norrius··on Image Scrubber: tool for anonymizing photographs taken at protests
Yes, that's it, thank you! And here's the English version of the article I linked above: https://yuzhikov.com/articles/BlurredImagesRestoration1.htm
norrius··on Image Scrubber: tool for anonymizing photographs taken at protests
If you do something really simple like a Gaussian blur (which is a type of convolution), it might be possible to find the inverse convolution (de-convolution) and restore the original image with some accuracy.

One method is the Lucy-Richardson deconvolution [1], which is an iterative algorithm, and here [2] is the best practical example I could find right away. Unfortunately the text is not in English, but the illustrations and formulae might be enough to give some intuition of the process.

[1] https://en.wikipedia.org/wiki/Richardson%E2%80%93Lucy_deconv...

[2] https://habr.com/en/post/136853/

norrius··on Implementing simple cooperative threads in C
I recall being taught a (fairly rudimentary?) explanation of the memory model that the available space is used from one side as the stack, and from the other side as the heap. Reading the article, I realised that memory management in a concurrent context is way more complex than that, but you don't go into a lot of details here (fair enough, that's not the main focus).

So each task gets 16k of stack space, but what if it runs out of it? These are allocated from the "main" heap, so they won't exactly run into each other, but might trigger UB or crash the program. This is something that a real scheduler (like the one in the OS's kernel) would have to deal with anyway, so how does, say, Linux, solve this? Giving a lot of stack space to each running thread would lead to fragmented and underused memory, or is it not a concern at the stack spaces you'd normally deal with?

norrius··on X
I am disappointed that the references at the end are made up and are not the prior art in the obviously important field of non-textual languages. I'd really love to learn about that "system for aromatic computation and its applications in cheese production [7]"!
norrius··on An equation that takes Pythagoras to a new level
These are bast shoes [0], known in Russian as lápti, which were the typical footwear in villages until the 20th century. They are strapped to the leg so that they don't fall off.

[0]: https://en.wikipedia.org/wiki/Bast_shoe

norrius··on China to inject $174B of liquidity on Monday as markets reopen
Given what appears to be exponential growth, the calculation seems to ignore potential future deaths in the currently known cases. Pardon the morbidity and cynicism, but maybe some of these 14628 people haven't had the time to die yet?

Wouldn't it be more appropriate to compare deaths (305) to the number of people successfully recovered (348 as per the same page)? This gives the survivability rate of 53%, which does sound scary (and I'd love to be proven wrong here).

norrius··on Predicting When P=NP Is Resolved
Given the next sentence (...if it isn't true, it seems like a polynomial algorithm would be unwieldy indeed), I think the GP actually meant P!=NP to be true.
norrius··on Anna Karenina Principle
I wonder if the French parts of the book were altered in the translation or kept as is. Or do you get excerpts of untranslated Russian instead, huh?
norrius··on You probably don’t need ReCAPTCHA
It could work... If you want to set minimal system requirements to visit your website.

It will also annoy users of password managers with auto-filling capabilities. "password" is normally used for actual passwords.

Besides, nothing stops the attacker from replacing your code with a faster implementation.

norrius··on How the quantum search algorithm works
> When I first heard about the quantum search algorithm I thought it [O(sqrt(N)) run time] sounded impossible. I just couldn’t imagine any way it could be true.

It's curious to hear this from Nielsen himself. Personally, learning about Grover's algorithm was when I realised why "if you're not surprised by quantum mechanics, you cannot have understood a thing" (attributed to Bohr, I think).

norrius··on The unreasonable effectiveness of mathematics in the natural sciences (1960) [pdf]
Was that meant as a joke or am I completely missing the point here? Mathematics provides plenty of tools to work with infinities. In plural, because there are quite literally infinitely many different infinities, which we know thanks to maths.
norrius··on Countries that have preoccupied Americans the most since 1900
I think generally having time-accurate flags and names would greatly improve the look of the chart. It is just weird having modern flags for the Axis countries in WW2, white-blue-red for the USSR (that's not even the Russian flag at the time), and so on.
norrius··on Mathematics I Use (2012)
For whatever reason, the link does not work for me. Google's cache doesn't seem to provide a copy, so here's one from the Wayback Machine:

https://web.archive.org/web/20180420113021/http://pub.gajend...

To the topic, I think this quote from the article is very important to note here: “Of course, I do not do all of this every day, but I have done all of it at one time or another and most of it regularly.”

It is nice to have an idea of how you write a parser for a language, but I do not believe the author advocates for being able to write one of the top of your head. Same with most other points.

norrius··on Cryptographic Right Answers
Indeed. What on Earth is “bzzrt pop ffssssssst”? Am I missing something? Google does not help at all.
norrius··on Some software cannot be used at Google
So basically WTFPL-licensed code is as good as not licensed at all, which is a nono?
norrius··on Some software cannot be used at Google
> WTFPL not allowed. We also do not allow contribution to projects under the WTFPL.

I am assuming this does not apply to personal projects, but then why would you contribute Google code to something that you cannot use anyway due to licensing issues?

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