zzless · HackerTrans

hace 22 díasdiscuss

The choice of pi as a number whose sequence of digits is random is a bit of a weak point of the argument in the post. It is not even known whether every digit 0-9 appears infinitely many times in pi (a weak version of the normal number conjecture). So we do not really know (but strongly believe) that the sequence of pi digits would truly appear random. This of course does not detract from beautiful arguments and the general ideas in this post.

zzless

hace 22 díasdiscuss

His definition of Kolmogorov complexity is a bit loose. The rigorous definition uses Turing machines (or Minsky, or Post, or some sort of lambda expression, etc.) so the size is something specific. Different versions of complexity defined this way may give different values but have the same properties and asymptotics so one might just as well stick with the Turing kind. Chaitin's theorem (about the limit of Kolmogorov's complexity being just entropy) holds for all versions as well.

zzless

hace 5 mesesdiscuss

With all due respect, no, it isn't. His drivel against set theory shows that he didn't even read the basic axiomatic set theory texts. In one of his papers, he is ranting against the axiom of infinity saying that 'there exists an infinite set' is not a precise mathematical statement. However, the axiom of infinity does not say any such thing! It precisely states the existence of some object than can be thought of as infinite but does not assign any semantics to it. Ironically, if he looked deeper, he would realize that the most interesting set theoretic proofs (independence results) are really the results in basic arithmetic (although covered in a lot of abstractions) and thus no less 'constructive' than his rational trigonometry.

zzless

hace 6 mesesdiscuss

I have a couple of EB6s to show to my students but ever since scientific calculators were allowed in written tests, I have never used one myself. Law of cosines is good enough for wind triangles :). Worked for a commercial test as well as the ATP. It is a beautiful device though ...

zzless

hace 6 mesesdiscuss

I am not sure why you are being downvoted but you are absolutely right: it is even in the name (WD stands for 'Water Displacement'). My reaction to this article was a huge: 'why?'. WD-40 is at best mediocre at everything it is used for. Wurth makes much more capable compounds for the came purposes. Their penetrating oil is unmatched. I guess as part of the popular culture, WD-40 has its value but I am not sure its chemical properties are all that unique.

zzless

hace 7 mesesdiscuss

>Also, possessive pronouns are exactly like in English, concording in gender with the owner, not the object.

This is only true in third person singular. For example, in first person singular: 'моя чашка' (my cup, 'cup' is feminine) vs. 'мой ключ' (my key, 'key' is masculine). Third person plural: 'ихнее дело' (their business, neuter) vs. 'ихняя забота' (their concern, feminine) although most educated Russian speakers would object to these pronouns as a bit too colloquial (although not as colloquial as 'евойная'). Same in second person singular: 'твой друг' (your friend, masculine) vs. 'твоя подруга' (your friend, feminine). In all of the examples above, the gender of the speaker/owner cannot even be determined (grammatically speaking).

zzless

hace 9 mesesdiscuss

Army PIT? Ah, this is not a good name...

zzless

hace 10 mesesdiscuss

This is a fine opinion, here is another one. Calling everyone who uses LaTeX cultists is a bit insulting. I do not particularly like LaTeX and use it only when a journal requires it in which case it is pretty much painless as I simply follow the provided template. TeX, on the other hand pretty much satisfies all my typesetting needs and I use it daily. I wish everyone would use TeX or LaTeX but I would not force it on everyone. Typst seems like a fine if a bit immature system but I truly hope it goes away, the sooner the better. Not because it is bad at what it does but because it solves a problem that does not exist and distracts from a standard that may not be perfect but has proved itself again and again. I am also weary of any piece of software that is controlled by a private entity, no matter how good the initial intentions are. Being open source is not really a guarantee of anything.

zzless

hace 10 mesesdiscuss

With all due respect to your perspective on TeX, isn't it the whole point? There are weaknesses in TeX (like using $ for both beginning and ending the math mode) but they are quite minor. Quirkiness is not a weakness but being a standard (since 1986!) is a major strength. The fact that it does not change is a blessing, truly. Python may be a fine language with a great community of supporters and I use it because I pretty much must but programming in something that is essentially a moving target is no fun. And I would take TeX macros over Python ugly syntax any day, no offense. Not to say I am right just to point out that taste is not necessarily a reliable guide.

zzless

el año pasadodiscuss

On the other hand here is a Long-EZ that gets 40 mpg flying at over 250 mph (so not quite 250 knots but still). The actual savings will be higher since one can fly in a straight line most of the time. It also avoids congestion and ... is simply more fun than driving. Also an auto-pilot in aircraft has been a real thing for quite some time while same in a car ... is still quite pathetic. I have eaten plenty of lunches comfortably while flying a plane while I would not be comfortable doing it while driving.

Long EZ reference: https://generalaviationnews.com/2016/05/25/going-fast-on-les...

zzless

el año pasadodiscuss

I was wandering the same thing. Quite often the insurance sets a much higher standard than what is legal. I had a lot of fun flying a local police helicopter as a commercial helicopter pilot with the police pilot (who only had a private certificate at the time) simply because insurance required a commercial pilot to be present in the cockpit.

zzless

hace 2 añosdiscuss

In my experience a more appropriate title for this book would be: 'Linear algebra done ok if this is your second time doing it'. I have seen way too many students who, after having taken a course that used this textbook, could not give an example of a linear operator (yes, I literally asked, show me an example of a linear operator in R^3) because they literally do not have the language for it (because 'matrices are bad').

zzless

hace 2 añosdiscuss

I have the same sentiment about TeX. The fact that the language has been stable for over 30 years is incredibly important to me. I also feel like I can do anything in TeX: I have written a C compiler in TeX as an academic exercise so I cannot take complaints about TeX's macros seriously.

zzless

hace 2 añosdiscuss

I am also doubting his claim that he had several students land without assistance on the first try. I have had a few students land with minimal assistance on the first try but I am quite sure that the airplane would be damaged had I refrained from making a couple of minor corrections. Some of those students were very talented (one soloed at 7 hours and went on to fly for Jet Blue eventually, of course this had little to do with my instruction) but they still needed a little bit of help the first time.

zzless

hace 3 añosdiscuss

I understand this is a (good) attempt at humor but this might be an interesting idea to see if Bluetooth leaks from inside the microwave oven (or from the outside in). Of course, the microwave has to stay off, naturally :)

zzless

hace 3 añosdiscuss

True, though this may mean many things. The only part of CFR 14 that mentions that a certificate is required for operating aircraft is CFR 14 61.3 which states that an unexpired certificate is required to `exercise the privileges' of that certificate. So if the PAO does not require the certificate to begin with, this part does not apply and one only has to comply with part 91 rules. Again, feel free to disagree, the sheriff told me this so who knows:)

zzless

hace 3 añosdiscuss

As I mentioned above it is not that the FAA waves their requirements as much as the FAA does not have jurisdiction over such operations (under appropriate circumctances).

zzless

hace 3 añosdiscuss

Here is a quote from AC No: 00-1.1A (Public Aircraft Operations): What Oversight of PAO Does the FAA Have? The FAA has limited oversight of PAO, though such operations must continue to comply with the regulations applicable to all aircraft operating in the NAS. The government entity conducting the PAO is responsible for oversight of the operation, including aircraft airworthiness and any operational requirements imposed by the government entity. The government agency contracting for the service assumes the responsibility for oversight of a PAO.

The military is another entity that operates aircraft outside of FAA jurisdiction. Even military airman certificates have to be `converted' to civilian ones i a military pilot wants to become a civilian pilot.

zzless

hace 3 añosdiscuss

Police in the US do not have to have a license to operate anything, including aircraft. In this case, insurance requirements take over though. They may have a legal right to fly but no insurance company would approve operation by anyone but a commercial pilot. I got a few hours in a local police Bell 206 because they needed a commercial pilot to fly while their official pilot only had a private license. Fun!

zzless

hace 3 añosdiscuss

This is indeed a nice idea, unfortunately the university (mine) gets kick backs from the book store. At the beginning of every semester every faculty gets an email asking us to 'encourage' students to buy their materials at the book store. Every semester I do what I always do and tell the students that the ($250!) book will not be used in class (although mine is just one in a sequence and the book is chosen by the whole department for the whole sequence) and give a half a dozen references to (excellent) free online books. Even then some students for whom the class is the terminal one in a sequence buy their books. Must be human nature at play. On a different note, as a flight instructor, when a future student asks me what to bring to the intro flight, I usually say 'lunch', since I provide everything else, including headsets. Yet half of them bring $500 worth of useless gadgets and expensive books (not, strangely enough, headsets) to 'be prepared'.

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