Lorentz forces and cheating at the Pinewood Derby - <AUTHOR> http://ch00ftech.com/2015/10/12/lorentz-forces-and-cheating-at-the-pinewood-derby/ <comment><USER2> This is one of the most enjoyable things I've ever seen on HN. It's just ... _fun._

I remember doing PWD with my dad when I was a kid, shaving #2 pencil cores to get graphite for the axles, making a batmobile one year, and generally doing things that probably had no influence on making the car faster, but that involved a lot of Time In The Shop Experimenting. PWD is the kind of thing that makes hackers out of impressionable youngsters.

<comment><USER3> From the article:

"They also didn't have any protection circuitry on them, but I figured that if my car burst into flames halfway down the track, it would totally be worth it."

That's the spirit!

</comment></comment><comment><USER4> When I was in Cub Scouts (30 years ago), the rules for Pinewood Derby were (at least as I understood them), fairly strict. You had to use the stock wheels and axles, and carve the car out of the provided block of wood, but you could weight the car any way you liked, up to the specified weight limit.

Given these constraints, there was one optimal design that would always win: essentially, a skateboard about 1cm thick, weighted exactly up to the limit with cast lead, with the bottom of the skateboard waxed. Everyone knew that was the optimal design, but it looked boring, and its performance was completely predictable, so almost no one used it. But every year, there was _one_ kid who (or whose father) cared more about winning than about having a cool PWD car...

<comment><USER5> I beat you by a fair bit on seniority--going on 50 years. I was the kid whose dad figured out that looks were nothing and weight was all. Somebody who optimized for weight _and_ aerodynamics might have beaten us, but that somebody didn't show up in our troop.

<comment><USER6> That's interesting, because my first year, I optimized for aerodynamics (and maximized the weight) but lost severely.

In later years, I realized that it had more to do with the wheel friction, and I made cars that were more interesting than perfect teardrop shapes and which also went much faster due to careful attention to wheel placement and lubrication.

<comment><USER7> I missed this... but yeah same thing here. We won every year lubricating the wheels and axles.

</comment></comment></comment></comment><comment><USER8> My son just joined the boy scouts (or Tiger Cubs or whatever it's called when they're in the 1st grade). I need to review this for... uhmm.. research purposes.

<comment><USER9> Just a comment, as fun as PWD can be, don't be that parent that clearly did all the work. The purpose is not to make a car NASA would be proud of, but to make the car with your son to end up with a car he made and is proud of.

Usually this results in a car that looks like and reflects the age of the scout (e.g. a Tiger Scout's (Kindergarten) car does not look like a Webelos (5th Grade) car.

Seriously suggest to your pack leadership that they add three races:

-Adult/Sibling -Adult Scouter -Adult Vintage

The first give you and your other non-scout kids an opportunity to be a part of things. You can make your NASA approved car that ultimately loses to the simple block of wood that five year old suzie makes.

The second gives the scouts a chance to cheer on their den leaders.

The third let's them see what PWD cars from pack in the day looked like.

Just some suggestions from an old Cubmaster.

<comment><USER8> Oh, I won't be, my comment was mostly tongue-in-cheek and also remembering how my the creations of my father and I never did that well.

Obviously you have to help a 6 or 7 year old to a degree, but I plan to be as hands-off as possible, when the time comes.

I like your idea of multiple races. I'll have to go and find my old PWD cars. They're somewhere...

<comment><USER9> It's really a blast to see the old cars, and the adult race is fun because then you can see some really great adult designs.

</comment></comment></comment></comment><comment><USER10> The simpler explanation is that the VW Diesel that won was cheating the system too ;)

</comment><comment><USER11> That was a lot of fun! A long time ago I designed an electromagnetic "coil gun" for BBs (.177 cal steel balls) as an exercise in electromagnetic fields. While it was mostly worked out in the 19th century it often felt to me like messing with more primitive forces than just charge and magnetic fields.

</comment><comment><USER12> I still remember winning "Best of Show" when I was a Tiger Cub. Took me a couple decades to realize this was a booby-prize.

</comment><comment><USER13> I suspect the real reason you lost is due to the aluminum track rails and eddy currents. You'd need a way to switch the thing off almost immediately.

</comment><comment><USER14> google cache [http://webcache.googleusercontent.com/search?q=cache:k-OXSfS...](http://webcache.googleusercontent.com/search?q=cache:k-OXSfSOTWYJ:ch00ftech.com/2015/10/12/lorentz- forces-and-cheating-at-the-pinewood-derby/&hl=en&gl=us&strip=1&vwsrc=0)

</comment><comment><USER15> Mirror? The site is down.

</comment><comment><USER16> My brothers and I we're in the scouts and my dad was a den leader. In pinewood derby season we would design the cars how we want, rasp, sand and paint them until they looked perfect to us, scouts, not parents. When that was done, my dad drill cavity in the car (one year he went through the top of a car into his hand), fill the cavity with molten lead to max weight, then we'd wood putty, sand and touch up the paint. My den had great looking cars and we dominated these races.</comment>


I miss Google wave - <AUTHOR> http://mashable.com/2009/05/28/google-wave-guide/

<comment><USER2> It was so cool, except that the scroll bars were terrible and it didn't work with existing email, so it wasn't really usable.

</comment><comment><USER3> I had big dreams of creating an IT support contact system using Wave. I imagined users initiating contact and being greeted by a robot which would ask them for the basic details. Based on this information they would be picked up by the appropriate support team member who would seamlessly take over the conversation.

I could foresee that continuous improvement of the robot to include logic to deal with common problems and questions would, over time, eat away at the number of support tickets which were mundane "easy fixes".

Then Wave "died" and I took a new job where dealing with helpdesk ticketing systems wasn't a pressing concern any more.

</comment><comment><USER4> Two things surprised me about this:

1 - I can't believe its's been over 4 year since Wave launched (and flopped)

2 - In those 4 years, UI trends have changed a lot. The UI in that screenshot looks horribly dated.

<comment><USER5> To be fair, Wave looked dated when it came out.

</comment></comment><comment><USER6> It's seems Apache Wave has moved from SVN to git since the last time I checked it out. Does anyone know if the project is still alive?

</comment><comment><USER7> Misleading title...should be: _Google Wave: A Complete Guide (2009)_

But yes, I miss it too.

</comment><comment><USER8> Well it's not like it's gone anywhere, you can still run an Apache Wave server if you want. Sure it's annoying to have to setup a server. I'm surprised a commercial hosting service hasn't sprung up.

</comment><comment><USER9> I miss Google Wave too. Seems stagnant, if not dead. :-(

</comment><comment><USER10> Rizzoma, Kune, Novell Vibe, Google Wave is still alive.

</comment><comment><AUTHOR> the google inbox announcement made me think of google wave. ahead of its time. maybe they will bring it back modernized...

</comment><comment><USER11> So jump in and help keep it alive... it's Open Source now and an Apache Software Foundation incubator project.

[http://incubator.apache.org/wave/](http://incubator.apache.org/wave/)

<comment><AUTHOR> thanks for the link!</comment></comment>


AlphaGo Is Not the Solution to AI - <AUTHOR> http://cacm.acm.org/blogs/blog-cacm/199663-alphago-is-not-the-solution-to-ai/fulltext <comment><USER2> It may not be "the solution", but no one in Deep Mind said it was. It doesn't particularly matter how journalists spin this stuff, as they clearly don't understand it anyway.

By the way, if Monte Carlo search worked, then we would have seen MC beating 9-dan pro's long ago, which clearly didn't happen, so the author's definition of "effective" lacks pragmatic insight - the real limiting factor in this sort of evaluative judgment.

The author doesn't seem to have watched any of the matches of AlphaGo vs Lee Sedol, though, as much of the pre-game and post-game discussion brings to light some important details surrounding specific implementation features in AlphaGo by Deep Mind. Glossing over that makes this article remarkably uncritical and uninformative.

Edit: it's one thing to combat hype, but representing the facts as they are in contradistinction to that hype is another matter entirely. Anti-hype is perhaps more pernicious in bringing about an "AI Winter" than is drumming up interest in what AI, or more accurately AGI, will be capable of in the not- too-distant future. And given current developments, I think the only AI Winter we have to fear is the one where uninformed persons accost us with misguided fears about AI and what its capabilities will be.

<comment><USER3> _It doesn 't particularly matter how journalists spin this stuff, as they clearly don't understand it anyway._

It matters because it could lead to another AI winter when the hype falls through.

<comment><USER4> There's not going to be another AI winter. The past AI winters occurred because people drastically underestimated how difficult AI would be. MIT (Seymour Papert specifically) thought computer vision could be solved by some graduate students as a summer project. Same story for other AI problems, e.g. NLP, speech recognition, general reasoning and inference, etc.

Once the difficulty of those problems started to be understood, of course funding dried up. Industry is focused on short-term ROI, so it's hard to get funding if the profits won't be seen for 50 years.

The difference is that now there's an entire string of profitable markets for solving near-term AI problems. AI is fundamental to the business models of some of the world's largest companies (i.e. Google). There's basically zero risk of an AI winter when we're on the verge of advanced robotics, Watson- style Q&A systems, self-driving cars, large-scale genomics, etc.

An _AGI_ winter is another story, but most AI work isn't really focused on serious, full-scale AGI right now anyway. That winter never ended and is ongoing. Everyone is focused on incremental AI improvements because no one really knows what's required for full AGI, and are in the meantime hoping they'll hit on it while building on known techniques like deep learning, comp neurosci, etc.

tl;dr: As long as investors continue to see marketable products for new AI developments anywhere in the next ~10 years, funding won't dry up again.

<comment><USER5> > There's not going to be another AI winter.[...] > The difference is that now > there's an entire string of profitable markets for solving near-term AI > problems.

As someone who experienced AI winter (and ended up leaving the field) and even attended the AAAI panel where the term was coined on stage, I am not so confident.

What happened then looks like it _could_ happen again. At that time there were tons of expert systems being deployed with high promises that they would revolutionize business and practical problem solving. Non-technical people from other fields were flooding in to sell "solutions." Dedicated workstations were proliferating.

The self-driving car hype is already at the same level as the expert systems hype was back then.

> tl;dr: As long as investors continue to see marketable products for new AI > developments anywhere in the next ~10 years, funding won't dry up again.

Well sure, that's true, but no different from saying "as long as house prices continue to go up there will be a housing boom."

</comment></comment></comment></comment><comment><USER6> Yes. We need more people like Langford and LeCun to push back on the AI hype. It's better for AI researchers to _under_ promise and _over_ deliver than the other way around. Otherwise we risk another "AI Winter," and that's no fun.

The challenge is that to approximately 99.99% of the seven billion people on this planet, including roughly every journalist, the recent progress made by AI researchers is indistinguishable from "magic."

When all those people try to reason about "magical things," they're bound to reach nonsensical conclusions and say nonsensical things. To them, debating on the promise of technologies like deep learning is a lot like debating how many angels can dance on the head of a pin.[1]

\--

[1] [http://www.straightdope.com/columns/read/1008/did- medieval-s...](http://www.straightdope.com/columns/read/1008/did-medieval- scholars-argue-over-how-many-angels-could-dance-on-the-head-of-a-pin)

<comment><USER7> Undepromise and overdeliver works well when you're building something for a customer, but I suspect when you're trying to demonstrate a technology that has the potential to be scary in the eyes of the public downplaying what it can do is probably the worst possible strategy. The way to take away the fear of the unknown is to make it unsurprising; for the public to accept AI their expectations are going to have to match the reality quite closely. If AI does less than they expect they won't buy it, if it does more they'll see it as an invasion of their privacy and they won't buy it.

</comment></comment><comment><USER8> Its just blatantly false to suggest that this victory means "games are solved". Games like chess and GO are games of complete information. Its just a matter of brute processing power, even if currently computers don't have the processing power to "solve" them.

Games of incomplete information, like poker, are much harder, if not impossible for computers to master without actual AI. It was only recently that heads-up, limit poker was "solved". Even in this case, the "solution" meant only that the computer could put forth a strategy that would not lose significantly over time, not a winning strategy. Games like no-limit hold em are infinitely more complex. This is true of heads-up, but vastly more so for full-ring games.

AlphaGo's victory has certainly been very impressive, but its also predictable. Given enough computing power, winning any game of complete information is just a matter of brute computing force. We'll see how computers (and real AI) can do in the future in regards to other games.

<comment><USER9> > Games like chess and GO are games of complete information. Its just a matter > of brute processing power, even if currently computers don't have the > processing power to "solve" them.

That's like saying public-key encryption is broken because we can brute force decryption.

When we talk about solving a game (or solving an optimization problem, etc), we aren't simply interested in whether the problem is computable. We want a efficient, polynomial-time algorithm if we're interested in the generalized problem (the size of the board is a parameter), otherwise at least something that runs and completes in a reasonable time if we're OK with solving only a particular board size (an instance, in terms of computational complexity).

The generalized go problem is PSPACE-hard or EXPTIME-complete depending on the ruleset you adopt. So it's not just a matter of brute processing power.

Now, most people outside theoretical computer science research don't care much about generalized games and asymptotics, they're fine with solving 19x19 Go instead of n x n Go. But that doesn't help you much: the only board size that has been solved is 5x5 [0], and there are only about 10^10 legal positions in a 5x5 board. The standard 19x19 has 10^170 legal positions! Good luck brute forcing it.

[0] [http://erikvanderwerf.tengen.nl/5x5/5x5solved.html](http://erikvanderwerf.tengen.nl/5x5/5x5solved.html)

<comment><USER8> >That's like saying public-key encryption is broken because we can brute force decryption.

No, that's like saying that public-key encryption will eventually be broken because at the end of the day its just about having enough brute force processing.

>When we talk about solving a game (or solving an optimization problem, etc), we aren't simply interested in whether the problem is computable.

No we aren't. But games of complete information that ARE computable, such as chess and GO can be removed from discussion. There is no question that these games of complete information are "solvable" with or without AI, since every move, from start to finish, can be calculated before the game even begins - its just a matter of processing power.

Which brings us to the question of AI and games of incomplete information. By definition full-ring no-limit hold-em is not computable. Even with infinite processing power, with every possible permutation calculated, there is no guarantee that a brute-force computer player is going to win full-ring no- limit hold-em. If there are multiple unknown players to act behind you, there is no way to compute with certainty what the outcome will be. This is where AI becomes really interesting as far as gaming is concerned.

<comment><USER10> > No we aren't. But games of complete information that ARE computable, such as > chess and GO can be removed from discussion. There is no question that these > games of complete information are "solvable" with or without AI, since every > move, from start to finish, can be calculated before the game even begins - > its just a matter of processing power.

In a theoretical universe, sure. In the one that we live in - no.

Let's assume that we can turn every atom in the entire universe that we know of into a 4Ghz processor, further assume that we can perfectly parallelize the search and that we can check one board position in one cycle on one of those processors.

How long would it take to check all possible 19x19 go positions?

(1 * 10^80 processors) * (4 * 10^9 checks) = 10^89 checks per second.

Total number of valid go board states: 10^170, therefore it would still take 10^79 seconds to check all the positions in order to find a perfect game.

Clearly, it _is not possible_ to ever brute-force go, no matter what kind of advances computing technology will take.

<comment><USER11> This argument surely discounts other computing models, like quantum computing.

<comment><USER10> Fair enough, if there is ever a quantum entaglement (or other type of course) based solution to go, then I will have been proven wrong. We'll see, but I'm not feeling very worried ;)

</comment></comment></comment></comment></comment></comment><comment><USER12> Ugh I've been following every AlphaGo discussion I can find, and it's always the same debate about what the significance of it is. I just want to make this final comment.

There is no significance to AlphaGo - to people paying attention to AI research. The methods aren't incredibly novel, the idea that CNNs could make very good value approximators isn't new, etc. I predicted computers would be beating expert Go players by the end of 2015, and was actually really disappointed when I was wrong. Turns out I wasn't, but it had just been kept secret.

However AlphaGo's victory is significant to the general public and the skeptics. It's a sign of the rapid progress being made in AI over the last few years. Rapid progress that shows no sign of halting.

Some of the people I spoke to about my Go prediction thought that it might be possible, but was probably too hard a domain. Hopefully those people will update their beliefs and be _a little_ more optimistic about NNs, and AI in general. They are extremely powerful tools that we are just figuring out how to use. Go will hardly be the last domain they succeed at.

<comment><USER13> I'd like people to make some predictions about what an ai will not be able to do in the next 10 years.

<comment><USER14> I'll go ahead and predict that we won't have human-level artificial intelligence within 10 years. As in you could throw it literally any task and it would handle it as well as a human and get better at it as fast as a human.

<comment><USER15> As it was said on BBC today: you can go into any kitchen and make yourself a cup of tea. Good luck with AI doing that.

</comment></comment></comment></comment><comment><USER16> My digestive system isn't the solution to my consciousness either but it's in some ways a part of it.

There is going to be no "solution" to AI.

Only emerging complexity which I am guessing at one point is going to give us something akin a semi aware entity. After that all bets are off.

</comment><comment><USER17> Who the heck was ever claiming that AlphaGo was an AGI? Straw argument much?

<comment><USER18> Well a bunch of people were confused and still don't know the difference between AI and AGI.

I actually think it's OK if some people think AlphaGo is more general purpose than it really is, because the general attitude or at least appropriate response to the likely development of AGI relatively soon still seems to be amazingly muted.

<comment><USER19> There was a time when AI meant AGI. AGI is a retronym induced by premature claims of the achievement of AI.

</comment></comment></comment><comment><USER20> Idea that AI will be a singular entity/solution/etc. needs to stop, it's like saying humanity only needs a single type of person. Generally speaking, only important measure is when there's not a single person that's able to out think one of many different instances of AI. That day will come, though when is not clear.

</comment><comment><USER21> The seemingly "poor" intelligence represented from the article, ironically, really weakens what intelligence is. In certain sense, this article really strengthen the importance of AlphaGo: AlphaGo does appear know Go, and the author seemingly have weak understanding of AI and GO, making it a poor intelligent being that is specialized in writing articles. Apparently Go is considered require more intelligence than writing normal articles. So AlphaGo performs well in a task that requires more intelligence, and the author performs poorly in a task that requires less intelligence. Does this make AlphaGo a better intelligent being than the author?

</comment><comment><USER22> Every accomplishment will seem obvious in retrospect. Who here honestly thought neural networks were going to be a dominant force in board game AI? Sure we cannot extrapolate, but that doesn't mean that we aren't building up effective tools for AI.

<comment><USER23> "Who here honestly thought neural networks were going to be a dominant force in board game AI?"

The potential for neural networks to learn to play games, by playing each other, has been apparent at least since NeuroGammon ([https://en.wikipedia.org/wiki/Neurogammon](https://en.wikipedia.org/wiki/Neurogammon)), in 1989. The "playing each other" mechanism is key, because it allows large- scale training.

The question is, what games happen to be well structured to allow so-called "credit assignment" so that you can know what states lead to wins across a reasonable spectrum of (unknown/unknowable) opponent plays.

According to the OP, it is known that you can do credit assignment in Go. ("For Go itself, it has been well-known for a decade that Monte Carlo tree search (i.e., valuation by assuming randomized playout) is unusually effective in Go.") I did not know that, but if so, it would simplify the Go problem, although the search space remains huge, etc.

<comment><USER24> Most scientific and engineering advancements are an incremental combination of what has come before. One can make all the predictions one wants, but until someone actually builds something working, it's just a hypothesis.

The key advancement in AlphaGo seems to be generating a subset good moves, as opposed to randomly selecting them, and determining whether a given configuration has a probability of winning. Monte Carlo Tree Search by itself only gets you to amateur ranks from what I read, but won't beat a pro player. Being able to combine the policy and value networks, and figuring out how to bootstrap and train them was where all the work is.

In hindsight, everything looks like an obvious combination of separate already-known-to-be-good pieces. I don't think this achievement should be hand waved away.

More importantly, the DeepMind folks are being pretty humble about it and not making the big claims everything seems to think they're making.

</comment></comment></comment><comment><USER25> Well, the Ford T was not the solution to electric, self-driving, suburban commuters either.

</comment><comment><USER26> Weak AI will never become self-aware. Actually, neither will strong AI unless we are including awareness as one of it's strong traits (some do, some don't).

Awareness is a virtue in and of itself, and any machine that has it will require an implementation of awareness itself, and that is regardless of the machine's intelligence. Awareness is about self motivation and the creating of its own goals. It's the generating of meaning to back one's words as well as actions, as even we often struggle to do.

As far as I am aware, no one at Deep Mind or IBM is actively working on intent and self-awareness. So for the foreseeable future, if a two-legged drone shows up at your door and points a gun at you, it won't be because AI has awakened. It'll be because someone at the CIA wants to kill you.

</comment><comment><USER27> This is a repost. The original link should be: [http://hunch.net/?p=3692542](http://hunch.net/?p=3692542) .

Other discussion from Yann Lecun [https://www.facebook.com/yann.lecun/posts/10153426027052143](https://www.facebook.com/yann.lecun/posts/10153426027052143) and [http://www.information-age.com/technology/applications- and-d...](http://www.information-age.com/technology/applications-and- development/123461099/google-deepminds-alphago-victory-not-%E2%80%98true-ai- says-facebooks-ai-chief)

</comment><comment><USER28> Didn't some AI researcher have a quote along the lines of "AI is whatever we can't do yet"?

<comment><USER29> Larry Tesler (source: [http://www.nomodes.com/Larry_Tesler_Consulting/Adages_and_Co...](http://www.nomodes.com/Larry_Tesler_Consulting/Adages_and_Coinages.html))

"Tesler's Theorem (ca. 1970). My formulation of what others have since called the "AI Effect". As commonly quoted: "Artificial Intelligence is whatever hasn't been done yet". What I actually said was: "Intelligence is whatever machines haven't done yet"."</comment></comment>


Show HN: Search compiler – human text based conditions - <AUTHOR> https://gerardrodes.github.io/search-compiler/ <comment><USER2> Whoa. This is a lot of potential. It's definitely unique and feels powerful. What would you see as the applications?

<comment><AUTHOR> I'll use it to provide easy rows filtering in a web app for users with no CS background

So they can type: bitrate above 1Mb

and get the items which have more than 1024 bits on the column bitrate</comment></comment>


P = NP Proofs: Advice to claimers - <AUTHOR> https://rjlipton.wordpress.com/2019/04/21/pnp-proofs/ <comment><USER3> On a related note, Scott Aaronson once wrote up a few heuristics he uses to quickly evaluate how likely a P/NP proof is to be incorrect: [https://www.scottaaronson.com/blog/?p=458](https://www.scottaaronson.com/blog/?p=458)

Aaronson's rules are more technical than the ones given in this article, the latter of which can be generally applied to most claimed (dis)proofs of famous open problems. In particular, poorly typeset papers from a solo, unknown authors are highly unlikely to be correct when they're claiming to resolve well known open problems.

In regard to the P/NP problem specifically, Aaronson's examples of weaker open problems which would likely be resolved first - or at least accounted for in some nontrivial way - are analogous to this article's point about proving weaker theorems first. It would be very suspicious for a proof that P and NP are separable (or not separable) to work at such a high level that it doesn't prove _also_ new results about the lower bounds of a litany of other problems.

<comment><USER4> Is all the good math institutionalized now (e.g., you can't do good math without all the benefit of learning background within the institution conventions)?

What's the intuition that an extremely important proof will come from someone who gets all the TeX tweaked to camera-ready perfection, goes around and gives the talks, and all the conventional things... rather than a genius out of nowhere who walks into a stranger's office, wordlessly drops on their desk a stack of handwritten pages wrapped in twine, and walks out, never to be seen again?

I was thinking of this because I once knew an autistic person, from some humble and isolated upbringing, who was getting some informal math instruction, and they told me they thought they knew a proof for P=NP. I considered it extremely unlikely, but not utterly impossible. (They reportedly tested "off the scale" high in some particular cognitive regard, and I'd noticed a couple minor superpowers.) If that person, to use them as an example, ever actually worked out the proof, and wanted to "turn it in" with their own judgment and access, I wonder where they'd go. And whether it would be somewhere that would take them seriously enough to look at it, and whether they could tell that a proof in unconventional terms had merit. If they get turned away from the first place, would they be discouraged and give up, or would they keep trying, there or elsewhere. If they persisted, would they appear to be a crank because of their persistence and frustration.

<comment><USER5> I think the intuition is that the best mathematicians, autistic or not, tend to be in academia already. So your prior for someone from the general population should be that they're more likely to be a crank than a genius, ie non-academia has many more cranks than geniuses.

<comment><USER6> > I think the intuition is that the best mathematicians, autistic or not, tend > to be in academia already.

Is that a safe assumption, though? Won't it limit the field to people who are happy making a low salary and don't mind teaching?

<comment><USER7> This is an asinine assumption. What of the incredibly "genius" poor folks who do not have the opportunities to join academia?

<comment><USER3> The point is that raw genius is insufficient for replicating Ramanujan-like accomplishments in the 21st century. It's almost irrelevant how brilliant someone is these days - if they haven't had the opportunity to learn a vast amount of theory, they can't really make significant progress towards theoretical problem.

The field simply has far less low hanging fruit than it did a century, or even a half-century ago. It's not reasonable to expect that a lone genius with little to no academic background in mathematics could resolve a famous open problem through sheer creativity. For literally generations the field's most intelligent researchers have spent their careers chipping away at this problem.

</comment></comment></comment></comment></comment></comment><comment><USER8> Carl Sagan once complained that all people who contacted him and claimed to talk with aliens always reseived simple unoriginal messages like love each other. Aliens never provided anything humans did not already know.

If someone comes up with a proof, they are in good position to troll.

<comment><USER9> Can you imagine if it was the other way? "Well I have no idea what it means, but they said these few sheets of math would be interesting to you and I thought you'd like to have them."

<comment><USER10> > Can you imagine if it was the other way? "Well I have no idea what it means, > but they said these few sheets of math would be interesting to you and I > thought you'd like to have them."

I can easily imagine that there exist lots of math nerds with a love for alien conspiracies in the internet who are keen on decoding these formulas.

<comment><USER9> I'd imagine something actually revolutionarily useful would probably have controversial assumption breaking conventions that people would be very skeptical of along with some novel concepts and definitions most wouldn't see any value or sense in.

If this were to actually happen, I think most people would discount it as gibberish because it would appear to be wrong things based on inventiveness and misunderstanding. Which if someone with a fields medal published you take seriously but if it's someone who works retail and is talking about aliens, you're probably going to ignore.

There's a twilight zone episode about that where someone travels back in time to prevent things but isn't taken seriously and can't stop disasters.

</comment></comment></comment></comment><comment><USER11> A simple litmus test that saves you from most clickbait, si whether the actual paper title contains, more-or-less, the equation P=NP or P!=NP. I cite Andrew Wile's proof of Fermat's Last Theorem, titled "Modular Forms, Elliptic Curves and Galois Representations" . The title will be about the how, and not some pop article title.

<comment> Ar-Curunir On as a counterexample, the paper showing that primality checking is in P was called "Primes is in P"

<comment><USER12> Another counterexample is "IP = PSPACE" by Shamir.

I think it's nice when titles include the main result plus a few words about methodology, like "IP = PSPACE using Error Correcting Codes", or "The PCP Theorem by Gap Amplification".

</comment></comment></comment><comment><USER13> >Yes, this post is about our own "claimers" in complexity theory.

>The TV Claimers meet a grisly end. We will not say any more about it. We want to be nice.

>Please: Do not stop reading. Yes we know that it is likely that no claimer really has such a proof.

I understand the author's frustration on the subject, but I don't think his disdain is warranted. This reminds me of the time Mehdi Sadaghdar, who runs the YouTube channel ElectroBOOM, disagreed with former MIT Professor Dr. Walter Lewin's proposal that Kirchhoff's Law is "for the birds".

Sadaghdar reproduced the results from Dr. Lewin's experiments, but proposed an alternative explanation about what could be happening. He created a video for Dr. Lewin, and stated that he was open to being proven wrong, ending that "either way, the science will win".

Dr. Lewin's response, instead of educational, was belittling where he generalized Sadaghdar as one of the group that holds to Kirchhoff's Law "religiously", and that he needs better education. The explanation was wrapped around in copious amounts of disdain. Sadaghdar eventually realized that they both fundamentally believed the same thing, and that their disagreement was only an error in communication, however, Dr. Lewin's videos are far more disliked than liked, and he didn't come out appearing to be the good guy from the exchange.

My point is, maybe generalizing the people you're criticizing, even though you "think the vast majority of claimers of P=NP or other big results have almost always worked alone" and comparing them to a group of people who die a "grisly" death in a fictional TV series, before you begin a lecture, isn't educational.

[0]: Sadaghdar's original video: [https://www.youtube.com/watch?v=0TTEFF0D8SA](https://www.youtube.com/watch?v=0TTEFF0D8SA)

[1]: Dr. Lewin's response video 1: [https://youtu.be/AQqYs6O2MPw](https://youtu.be/AQqYs6O2MPw)

[2]: Dr. Lewin's response video 2: [https://youtu.be/ototTU5NUNA](https://youtu.be/ototTU5NUNA)

[3]: Dr. Lewin's response video 3: [https://youtu.be/d_XqrZo5_7Y](https://youtu.be/d_XqrZo5_7Y)

[4]: Sadaghdar's last video: [https://www.youtube.com/watch?v=Q9LuVBfwvzA](https://www.youtube.com/watch?v=Q9LuVBfwvzA)

<comment><USER14> I was bracing for you to reveal that Sadaghdar was right all along and that Dr.Lewin was wrong but.. in the end it's about whose youtube video like / dislike ratio is better?

<comment><USER13> Yes. And Sadaghdar was right all along, but turns around so was Dr. Lewin, it was an error in communication. Dr. Lewin defined Kirchhoff's Law in a particular way that Sadaghdar didn't agree with.

I'm sorry if that wasn't dramatic enough for you, but that's the only objective metric I have to show how either of their responses was received.

PS. Sadaghdar has 2.5 million subscribers, and Dr. Lewin has just under 400k, These are videos with thousands of like/dislike votes each.

</comment></comment></comment><comment><USER15> I'm a crank. I found this article very valuable.

In 2010 I put online a brief refutation of the EMH, the efficient market hypothesis. Here it is: [https://arxiv.org/abs/1011.0423](https://arxiv.org/abs/1011.0423)

If I had seen this then, I think I would have followed the directions in the inset box, where the article suggests saying something like: "The reason I succeeded in finding an algorithm for P=NP is that I noticed that... No one else seems to see that this insight is very powerful. It is very useful since it implies ..."

I could have simply written: "Nobody has bothered to test the Efficient Market Hypothesis, but since I have some background in computer science I made an unusual mental connection, and it follows that it doesn't need to be tested. It cannot be true."

(My proof outlined a way to show it has to be false.) I remember my thinking at the time was that I didn't need to explain it at all, just make it correct and brief.

At the time, I didn't want to include anything personal in the paper. Perhaps I should have. It's not a very good paper.

<comment><USER16> Isn't this equivalent to saying "I have incorporated a company, it owns a lockbox, and only I know what's inside." Only an insider knows the real value. But even Wikipedia's summation of the strongest version of EMH says that it's impossible if insider information can be hidden: "If there are legal barriers to private information becoming public, as with insider trading laws, strong- form efficiency is impossible"

[https://en.wikipedia.org/wiki/Efficient- market_hypothesis#St...](https://en.wikipedia.org/wiki/Efficient- market_hypothesis#Strong-form_efficiency)

So it seems that your contention- that insider information that hasn't leaked yet obviously won't be reflected in the price- is spelled out already.

<comment><USER15> okay so going with your analogy it's like publishing a picture of what's inside the vault but you publish the picture encrypted. imagine the encryption is a 20-letter random password in winzip (imagine winzip is secure) with the picture of what is in the vault. Although only an insider knows what's in the vault, the public gets the encrypted picture. Every day you publish one more letter of the passwrod. So if the password is p?jbAL;nQpg-37(z(feH then on day 1 you publish just "p" (the first letter) so now it's as strong as 19-letter password since you gave them the first letter.

I don't know what will happen exactly between day 1 and day 20, but on day 19 anyone can just try every 20-leter password with the first 19 letters you've published by that date. So if by then you've published p?jbAL;nQpg-37(z(fe already they'll just try

p?jbAL;nQpg-37(z(feA p?jbAL;nQpg-37(z(feB p?jbAL;nQpg-37(z(feC p?jbAL;nQpg-37(z(feD

in winzip. Anyone can just try all of them until they find the one that unlocks it. So on day 19 if it's worth knowing, for sure someone will take a minute or two to try it. Not that hard if there's just 1 missing letter.

So for sure if you tell people it's a 20-letter password and give them 19 letters they will figure it out before you've given them the last letter.

All right, but on day 1 nobody can guess all 20 characters in the password. That's too hard. it's impossible.

So every day you make it easier, but it'll be "broken" sometime between day 1 and day 20, assuming that the insider information doesn't leak in any other way. that means that someone will break it but not on day 1. on some day between day 1 and day 20. The person who analyzes it "best" will have the insider information first, but for sure we don't have to wait until day 20 because by then it's ridiculously easy to analyze.

meanwhile you're making the analysis easier and easier. the person who can do the analysis best will have it first, and this proves that there's no "infinitely great analysis" already being done all the time by public markets. it's a simple demonstration of this fact. I don't think you actually need to do the experiment to now the results. hope this helps.

<comment><USER17> Your explanation does not disprove the EMH as far as I can tell.

Sure, there's some people who will have information sooner than others. In fact, the EMH says that "people who outperform the market do so based on chance" and it's expected that some people do win some of the time.

What better test of chance than who guesses the password soonest by luck?

Okay, fine, it's not luck you say, it's whoever has the best supercomputer to crack the password each time that happens. However, in reality, contrived examples like brute-forcing passwords aren't frequent parts of the stock market. Rather, it's events that traders predict the potential impact of, which is much closer to a random affair.

What you've shown in your comment is that it's difficult to clearly define private and public information in some contrived cases.

<comment><USER15> I think difficult analysis is a very frequent part of the stock market.

My argument was not so much about luck as about speed of analysis. EMH doesn't allow some people to analyze information faster than others. For example if Intel always releases a 450 page earnings at 11 o'clock, and it takes 4 hours for the market to really analyze it because it's written really abstrusely and that's the fastest anyone can read and figure out its meaning, then under the EMH there's no scope for 1 specific trader to read it in 1 hour and perform the analysis faster, before the price has adjusted to the new information. In fact, under the EMH the price has to instantly fully reflect the implication of the information of the report the moment it is released. If two hours in, a famous analyst (Warren Buffett let's say) tweets about it, and that tweet moves the price, under the EMH it must have moved the price because of new information. It can't just be because the famous analyst is smarter and analyzes better and faster than the rest of the market. Not possible.

That doesn't mean that until the tweet the analyst's better-than-market analysis is somehow "private" (rather than public) for 4 hours. there's no new information, it's just that the public price doesn't fully reflect the completed analysis. The market can be a bit dumb.

But how do you know the facts I just gave are true? How do you _know_ the completed analysis can't be factored into the price the instant the report is released? (The price does jump instantly.) Maybe it jumps to the new fully completed analysis price? Maybe everything I wrote is not true and in fact the market is perfectly efficient, and only new information, or stochastic events, change the price? Maybe it fully reflects all public information all the time?

So I showed how to show that analysts can't all work instantly, yes, under a contrived example. The EMH doesn't require that markets only be efficient under conditions that aren't "contrived". But rather, all the time. you can run the experiment and show it if you want. you can literally see the stock market figure it out. They could also figure it our wrong. Maybe early on #117 will spike (so that prices look like this: [https://imgur.com/a/C782Fgt](https://imgur.com/a/C782Fgt) ) - it could be for any reason. Maybe a false rumor that it was leaked (a false leak), whatever. But the market gives the rumor just a 10% chance of being true. But regardless of the reason for the spikes, at the end there must be a single spike, in the value of the stock that actually wins. it must be around $1 billion since it'll have that in cash. (It's important that people actually believe this will happen.)

</comment></comment></comment></comment></comment><comment><USER18> If you have a proof that P=NP, the best way to demonstrate that is to solve a nice, hard 3-SAT problem. Maybe reversing something like siphash, or something similarly difficult.

Set up a web page where someone can put in their 128-bit SIP hash and their plaintext, and you'll tell them the 64-bit secret used to hash it.

 _Everyone will believe you._

For extra bonus $$$, there are various large prizes (e.g. $1M USD) you can win if you can "break" various things which are trivially breakable if P=NP. Might as well cash in there, too before they pull the plug on the contest…

<comment> GuB-42 It is addressed in the article. The idea is that it is not a good proof.

Solving a hard problem with code doesn't mean that you solved the general case. For example your algorithm may work in polynomial time for some specific 3-SAT problems or hashes up to a certain length. It may be huge but it doesn't mean you proved P=NP.

Furthermore, P=NP doesn't mean you can easily solve NP-Complete problems. What if N^100 is the best you can do? It may be polynomial but it is useless. In fact, small steps are expected. And going straight to a workable algorithm is suspicious.

<comment><USER18> > _Solving a hard problem with code doesn 't mean that you solved the general > case._

If we're talking about P=NP, 3-SAT _is_ the "general case". That's why I picked it, since all NP problems are reducible to 3-SAT in polynomial time and space.

<comment><USER19> Saying that you solve a specific case of satisfiability problems (e.g., siphash) is not proof that you can solve any 3-SAT problem. Graph coloring is a great example of this phenomenon--graph coloring is NP-hard, but most graphs can be colored very efficiently in polynomial time.

</comment></comment></comment></comment><comment><USER20> By the name, I was expecting this article to be much more technical, giving examples of common errors made by attempted proofs or reasons why certain cruxes in possible proofs would be difficult to overcome.

<comment><USER21> So was I, something more like this:

[http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.32....](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.32.3404&rep=rep1&type=pdf)

Still, I thought it was a nice post.

</comment></comment><comment><USER22> I recently became interested about P=NP, the reason was learning. And I became crankish, in the sense of trying to understand the problem myself.

My advice is - learn about naturalness. Monotone circuit bound in CLIQUE in particular is an interesting result, which knocks out many straightforward approaches to show that P=NP. The Wigderson recent book gives a very good overview.

However, I wish in some sense this was better explained, that there was more examples of algorithms that cannot work because they can be, in some sense, represented as monotone circuits.

</comment><comment><USER23> Very smart people have tried for a very long time to show one way or the other. We don't know if P = NP (seems unlikely) or if P != NP (seems likely). But there is no proof either way.

If P = NP, then we can generate solutions to very hard problems as easily as we can verify given solutions to those problems (both in polynomial time). Again, this seems very unlikely.

<comment><USER24> > If P = NP, then we can generate solutions to very hard problems as easily as > we can verify given solutions to those problems (both in polynomial time).

Knuth himself, for example, has casually expressed the opinion (not a proof) that P=NP in the past. When you say "as easily" it belies the nature of polynomial time questions. If it turns out that we can produce an algorithm for 3SAT that is O(n^1e72), then that will in fact prove that P=NP. But this does not make any practical problems "easy".

<comment><USER25> No need for n^1e72, a SAT instance with a couple of hundred variables can usually be solved easily, industrial instances are often hundreds of thousands of variables. Even a O(n^10) algorithm would be of MASSIVE theoretical interest, but almost no practical value.

</comment></comment></comment><comment><USER26> Here are two good practice problems for testing your personal bogometer:

[http://sparsey.com](http://sparsey.com)

[https://www.agilepq.com](https://www.agilepq.com)

It's not P=NP but two similar problems that attract a lot of quackery.

<comment><USER27> Are those even serious sites? They look like what happens when a Markov chain program meets a mediocre web designer.

<comment><USER28> I can assure you that Rod Rinkus', Sparsey creator, work is very serious. He is a computational neuro scientist I've actually been working with him since october. But he has said the website has needed some updating for a while now. One of my primary jobs will be to get the demos up and running with a more updated feel. I'm not sure of the other site, but I have done the work to recreate Rod's work from scratch and he has done several tests to prove the system works. Most of his work was done through DARPA and ONR research grants. He has only really recently decided to try to make a profitable company off of it recently, before that it has always been funded through research grants.

As for the look and feel of the website, which in reality has no merit on whether the research is legitimate or not, I have joked that he just needs to market himself better and he has laughingly agreed. But you can hit him or I up if the research is to hard to understand from a glance. We are trying to practice how to pitch it to people better so it's easier to understand. But once every thing clicks, its actually a really simple concept, it's just that its a highly recurrent system. I had to program it out piece by piece before things started making sense.

</comment></comment></comment><comment><USER29> Here is a guy, who did not know LaTeX, but written in MS word:

[https://www.quantamagazine.org/statistician-proves- gaussian-...](https://www.quantamagazine.org/statistician-proves-gaussian- correlation-inequality-20170328/)

</comment><comment><USER30> Thoroughly boring and conventional advice. How about some advice from the dark side: First, become a distinguished researcher in the field so that there is no other choice but to take you seriously. Then write a giant multi-part book- length paper consisting almost entirely of endless definitions and lemmas referring to each other. To those brave souls who actually try to read and understand the paper and who claim that they have found a problem with it, reply that they have profoundly misunderstood the nature of the work and should read the paper more carefully.

Not actual advice of course. I just find the controversy surrounding Mochizuki's purported proof of the abc conjecture (HN discussion: [https://news.ycombinator.com/item?id=18034714](https://news.ycombinator.com/item?id=18034714)) fascinating. Something like this could easily happen to P=NP when one cannot confidently state whether we have a proof or not.

</comment><comment><USER31> I dislike the early section about arrogance. Who cares? I don't care if someone is being arrogant, humble, or anything else, when it comes to mathematics proofs. Imagine if Hardy had scolded Ramanujan for being "arrogant" and dismissed his correspondence?

At best, by trying to judge arrogance, you're trying to use it as some type of correlate with being a crank and more quickly dismiss a claim without spending the effort to read it.

At worst, it's trying to entrench the superficial credential of mathematics academia and journal publication style of collaboration and peer review, which frankly (and especially in mathematics, where polymath amateurs can easily be responsible for ground-breaking solo work) is overdue for being replaced by a more fully open, unrestricted participation model of discovery and publication.

Some arrogant cranks are going propose time-waster claims. Just accept it. Don't care if they are arrogant or not.

</comment><comment><USER32> Just wondering, why do people not use Coq/Isabelle/Agda/etc in order to check such proofs? Wouldn't that save them from the "shame" of producing yet- another-incorrect P(!)=NP proof?

<comment><USER33> Because that's an extremely large amount of work to do, even if you're already familiar with the tools.

It wouldn't be quite so bad if there were a huge repository of already proven theorems you could pull from. But in reality you'll probably find yourself defining what a Turing machine is, what asymptotic complexity is, deriving results like the master theorem, and a thousand other trivialities you would just skip over in a paper.

It is especially problematic that there isn't a common repository of reference implementations of well-known unproved propositions. It would be so easy to make a subtle mistake in your definitions that allowed an existence proof to go through in a way that wouldn't generalize to the actual definition. For example, when you define probabilistic computation, if you declare that a probabilistic gate is a stochastic matrix with real number entries, you will incorrectly find that there exists probabilistic programs that solve the halting problem.

<comment><USER3> _> For example, when you define probabilistic computation, if you declare that a probabilistic gate is a stochastic matrix with real number entries, you will incorrectly find that there exists probabilistic programs that solve the halting problem._

Great example! Do you have an outline of this proof? I can see the error in defining a unitary matrix over R instead of C, but I'm not immediately seeing how you can exploit that error to bypass the halting problem.

I'm guessing the concrete error would be introduced by overlooking that the real-valued matrix won't preserve the correct probability amplitude? If so, what's the next step to (falsely) deciding that a given algorithm will complete?

<comment><USER34> Maybe the problem is that you can use uncomputable numbers in the matrix? (e.g. [https://en.wikipedia.org/wiki/Chaitin%27s_constant](https://en.wikipedia.org/wiki/Chaitin%27s_constant))

<comment><USER3> Unless I'm misunderstanding the parent commenter's definition of a probabilistic gate - I'm assuming a unitary matrix - then that shouldn't be an issue. Chaitin's constant is in both R and C. More generally, all uncomputable real numbers are also in C, because C is complete over R.

In other words that shouldn't be the issue, because the correct "setting" for the stochastic matrix still allows for that possibility. It's not something you introduce by using real entries.

<comment><USER35> I don't think the issue here is requiring the matrix coefficients to be real (I don't think that complex values make sense there at all), but allowing arbitrary real numbers. In such case you can show algorithm, for which there exist matrix with real coefficients such that it solves halting problem - <USER2> trick is encoding infinite amount of information in the real constant.

<comment><USER3> Complex values (a unitary matrix) make sense if the stochastic matrix is representing a probability amplitude.

</comment></comment></comment></comment></comment></comment></comment><comment><USER36> This article should really be deleted. It's giving crackpots advice for camouflaging their crackpottery, forcing serious mathematicians to waste more of their time determining its legitimacy.

<comment><USER37> Actually, if a crackpot can faithfully camouflage their output then they are probably not crackpotty enough to deserve deletion without any consideration at all.

Imagine, you have succesfully proved P eq/neq NP... but you can't be bothered to learn LaTeX or convince someone who does to typeset your work? Unfreeking likely.

The vast bulk of the junk can be disregarded by simple heuristics because the crackpots are unwilling or unable to meet even a very low bar. Telling them precisely where the bar is will only get a small amount past it.

</comment></comment><comment><USER38> Why to discourage people to try things with low probability of success? It's hard to find these guys, let them be happy at least for a while

<comment><USER39> I received an email from someone I met recently:

> I inted to start doing a project on what causes Parkinson's Desease using > Python , Big Data, , Data analyt and Nvidia Supercomputing. You have a > skillset that can hel sovle this problem and I coul use your help. If we are > successful then we can do the same for other medical deseases.

He was middle-aged and had learned to code a few months ago. He did not seem interested when I told him that the field was called 'bioinformatics' and that there were many people working on these problems already. This is not a "low probability of success", this is a zero chance of success.

In these cases, I'm not sure what the right course of action is. I don't think discouragement even does anything; for a particular kind of person (who has the arrogance to think they could cure a major disease as though it were a blue ocean problem), active discouragement just solidifies their resolve. I like to think that if they could redirect their ambition to a small and tractable problem, they might actually be able to make a contribution (even Terry Davis of TempleOS fame was able to produce something inspiring, which he wouldn't have done if he had been trying to Solve a Big Problem).

But then I think you're probably right, that there is no real hope, and the best course is to ignore them so I'm not wasting my time, but also to let them have a dream and feel like they're doing something.

<comment><USER40> "He was middle-aged and had learned to code a few months ago."

I don't like the idea that older beginners are necessarily worthy of contempt.

I do like the idea of suggesting that he take some courses in bioinformatics.

I don't know who Terry Davis is, but does he deserve the "even" qualifier before his name?

<comment><USER41> Many similar cases approach anyone who is viewed as capable in tech, from app ideas to game ideas to buzzword mashups. They usually come from people who have spent minimal time trying to build their own capability or researching prior work done in the domain. They are only focused on making their own dream a reality and latch on to the one they perceive as able to realize it.

What they need is a mentor. Which is fine, of course. Mentorship is one of the best thing to look for when you're starting out. The issue is that mentorship cannot begin without humility from the mentee. Even if the mentee presented a legitimately great idea, an idea is still not an equal contribution, because they will need to be guided through the whole process.

So I think the disdain is warranted. Not because of age or inexperience. But because they're engaging a mentor with an offer of partnership. It's very arrogant.</comment></comment></comment></comment>


How I Built the Flying Cart (1960) [pdf] - <AUTHOR> http://www.vintageprojects.com/go-kart/flying-hovercraft.pdf <comment><USER2> Reminds me of a real version of what this ad in every Boy's Life magazine promised for at least 30 years. I always wondered if the mail-order hovercraft plans encouraged or dashed the dreams of kids across the US for over 2 generations... [https://books.google.com/books?id=WRJwbbbmYCUC&pg=PA68&lpg=P...](https://books.google.com/books?id=WRJwbbbmYCUC&pg=PA68&lpg=PA68#v=onepage&q&f=false)

</comment><comment><USER3> When I was a kid my buddy and I built so ething like this with plywood, a dozen garbage bags, about a mile of duct tape and three vacuum cleaners. Mom was not amused when she saw how I I'd cut up her vacuum cleaner hose.

<comment><USER4> Please tell us that now you work for NASA/JPL or something related to engineering :)

That would make the sacrifice of that hoover totally forgivable!!

<comment><USER3> I write novels, had a magic prank show on A&E and I just starred in a special for Discovery Channel involving great whites sharks.

So it kind of worked out.

</comment></comment></comment><comment><USER5> Reminds me of Lindsay Technical books. Used to love reading those things when I was a kid.

[https://www.youroldtimebookstore.com](https://www.youroldtimebookstore.com)

<comment><USER6> Wow! I learnt that FAA at some point stood for Federal Alcohol Administration: [https://www.youroldtimebookstore.com/v/vspfiles/photos/YOTB2...](https://www.youroldtimebookstore.com/v/vspfiles/photos/YOTB20935-8.jpg)

</comment></comment><comment><USER7> What i like is how simple and easy it is to read the documentation :)</comment>


The Limits of Explainability - <AUTHOR> https://www.wired.com/story/the-limits-of-explainability/ <comment><USER2> In the math example I had an intuition of the wrong price(10 cents) but, I also had an intuition that it was wrong too. I knew I was going to need to do the math, but didn't bother cause I knew the article was going to tell me in few more seconds of reading.</comment>


Reverse Rental Directory - <AUTHOR>

I'm in the process of finding a house to rent and have been struck by the fact that it is universally a listing of houses and not of renters.<p>Does anyone know of a site which allows renters to post their requirements, rooms, rent / buy, down payment etc... ? <comment><USER2> I am always astonished by this, too. Finding housing and finding a job both seem like problems that are really ripe for some sort of optimizing solution. It's an incredible amount of work for the people on both ends of the process — renters and landlords; employers and would-be employees — because there is so much information to sort through, in a plethora of non- standard formats. Looking through listings (or piles of applications) is truly the lowest common denominator.

Anyway, if you're not aware, Craigslist has a "Housing Wanted" section: <http://sfbay.craigslist.org/hsw/> (for the Bay Area)

Also, although this is not what you asked for, <http://www.padmapper.com> does make searching through listings a lot less painful.

<comment><AUTHOR> Thanks, the housing wanted is indeed the concept I was looking at. Somehow I had missed it on Craigslist.</comment></comment>


Show HN: Kube Namespace – Run Multiple kubectl Commands In The Same Namespace - Noah-Huppert https://github.com/Noah-Huppert/kube-namespace <comment> Noah-Huppert I made this tool to solve the problem of being slowed down by having to add the `--namespace` argument to every single `kubectl` command invocation:

      # Before
      kubectl --namespace foo-bar get pods
      kubectl --namespace foo-bar describe pod/bazz
      kubectl --namespace foo-bar exec bazz

      # After
      kubens use foo-bar

      kubectl get pods
      kubectl describe pod/bazz
      kubectl exec bazz

I hope this helps others who have encountered the same issue.

</comment><comment><AUTHOR> This is a built in feature of `kubectl`:

        kubectl config set-context your-context --namespace some-namespace</comment>


Crystal Mimics Learning and Forgetting - <AUTHOR> http://nautil.us/blog/this-crystal-mimics-learning-and-forgetting <comment><USER2> "This bit of silicon mimics learning and forgetting"

The philosophical implications of this research is not what's interesting. Computers are not brains but they mimic a lot of its behaviour. The title is mostly clickbait.

<comment><USER3> I think the idea is that this is found in nature as a single material. Silicon doesn't do anything remotely brain-like until humans etch intricate patterns in it and run precise electrical currents through them.

I think the use of neural networks is a kind of boring approach to studying this crystal. Of course the algorithm it uses is going to be more adaptable than an arbitrary algorithm selected by the researcher, otherwise they would have chosen a different algorithm to prove the truism.

I'm more interested in hearing about the physical mechanism by which a crystal manages to store and forget information, and some theory about how this could have come to exist without resorting to life-based arguments like survival of the fittest or evolution.

<comment><USER4> Discoveries like this combined with discoveries about thermodynamics models mimicking "societal" behavior like cooperation will change how we define sentience and conscious "life" and life processes.

</comment></comment></comment><comment><USER5> The standards for what qualifies as "learning" appears to be very low here. A low endurance memristor would qualify here.

</comment><comment><USER6> am I the only one imagining some crystal based lifeform out there, somewhere?

</comment><comment><USER7> If you put a black box over it, the crystal is exhibit one type of learning mode that complex learner like humans has many modes; the ability to adapt and filter</comment>


Boys and Girls may get different breast milk - <AUTHOR> http://www.scientificamerican.com/article.cfm?id=boys-and-girls-may-get-different-breast-milk <comment><USER2> Is not just "food" what is passed with breast milk, also beneficial bacterias [http://www.sciencedaily.com/releases/2012/04/120429234641.ht...](http://www.sciencedaily.com/releases/2012/04/120429234641.htm) Not sure how that regulates itself regarding sex, age or health of the child, but seems that it happens.

<comment><USER3> Also, immunogoblins and other stuff we do not know.

</comment></comment><comment><USER4> It raises the question not just about twins but also about wet nurses. I mean its a pretty normal tradition for mothers to 'outsource' their breast feeding to other mothers, especially if they're tired or sick.

Also what about formula milk?

<comment><USER5> What about formula milk? The long term benefits of breast feeding are so tenuous that I can't imagine there's a practical significance to the difference between breast milk produced for girls versus boys in human babies: [http://www.skepticalob.com/2013/05/world-health- organization...](http://www.skepticalob.com/2013/05/world-health-organization- no-long-term-benefits-to-breastfeeding.html).

Studies like these are valuable, but it's tempting to jump from interesting observation to policy recommendation without keeping in perspective (or even bothering to quantify) the magnitude of the impact.

An excellent blog post on the state of research into breast feeding: [http://www.skepticalob.com/2013/06/two-crappy-new- breastfeed...](http://www.skepticalob.com/2013/06/two-crappy-new- breastfeeding-studies-make-irresponsible-claims-of-benefits.html)

<comment><USER6> > The long term benefits of breast feeding are so tenuous

This is a joke, right?

Simple reasoning and deduction will lead you to the right answer. We evolved to drink the milk of our mothers, not a chemical concoction derived from the milk of cows fed by corn.

<comment><USER7> We also evolved with immune systems. This does not mean that supplementary tools such as antibiotics and vaccines are not useful.

I believe rayiner's point is that infants can thrive on formula milk as well as breast milk. Please don't mock parents who choose to formula feed; there are many cases where it is preferable and/or necessary, just as there are cases where it is necessary to use antibiotics to supplement the body's immune system.

<comment><USER6> > Please don't mock parents who choose to formula feed; there are many cases > where it is preferable and/or necessary

And where have I done that? Formula is a fantastic invention that can specifically assist in very difficult situations.

But just as it is clearly inferior to take antibiotics daily because it is too inconvenient to wash one's hands ... so to is it clearly inferior to use formula when the mother is capable of breastfeeding, but can't be bothered.

<comment><USER8> While I can certainly see the downsides of abusing antibiotics, I don't "clearly" see comparable downsides, in likelihood or magnitude, to using formula.

<comment><USER9> Formula lacks the live immune system cells the mother passes to the baby. Maybe someday we will develop nanobots to substitute for that. Till then, that's a clear downside.

</comment></comment></comment></comment></comment></comment></comment><comment> nappy-doo I have nothing constructive to say about the article, but for the record: gender is chosen, sex is not. I wish the world would get this right, especially Scientific American, which got it wrong in the second sentence.

Here's an interesting link: [https://books.google.com/ngrams/graph?content=gender%2C+sex&...](https://books.google.com/ngrams/graph?content=gender%2C+sex&year_start=1800&year_end=2000&corpus=15&smoothing=3&share=&direct_url=t1%3B%2Cgender%3B%2Cc0%3B.t1%3B%2Csex%3B%2Cc0)

<comment><USER10> The world doesn't seem to agree with you. Straight from Wikipedia [1]:

 _Gender is the range of physical, biological, mental and behavioral characteristics pertaining to, and differentiating between, masculinity and femininity. Depending on the context, the term may refer to biological sex (i.e. the state of being male, female or intersex), sex-based social structures (including gender roles and other social roles), or gender identity. ... the meaning of gender has undergone a usage shift to include sex or even to replace the latter word. .... Gender is now commonly used even to refer to the physiology of non-human animals, without any implication of social gender roles._

[1] [http://en.wikipedia.org/wiki/Gender](http://en.wikipedia.org/wiki/Gender)

<comment><USER11> From the same article:

>The modern academic sense of the word, in the context of social roles of men and women, dates from the work of John Money (1955), and was popularized and developed by the feminist movement from the 1970s onwards (see Feminism theory and gender studies below). The theory was that human nature is essentially epicene and social distinctions based on sex are arbitrarily constructed. Matters pertaining to this theoretical process of social construction were labelled matters of gender.

I think most places people hear it is that gender is the male/female/other self-description, and sex is the physiological state.

<comment><USER12> Most transgender social justice warriors or gender studies majors maybe. Not most people in general.

The vast majority of the people out there don't distinguish between gender and sex. Especially since only about 0.5% of the population identifies as a gender other than their physical sex.

<comment><USER13> There's a lot of terminology that the vast majority of people understand poorly. By itself, that hardly seems a good reason for a (supposedly) scientific magazine, particularly when using 'sex' exclusively would understood by everyone.

<comment><USER12> It probably comes down to the fact that the people practicing physical "hard" sciences do not particularly care about or trust the conclusions drawn by the "softer" sciences (sociology, gender studies, psychology)

<comment><USER13> Maybe so, but the person writing this article isn't a practitioner of hard sciences, she's a journalist.

<comment><USER12> A journalist for a magazine focused on presenting hard sciences to the masses.

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER14> How does the mother's body know the sex of the child? Is it detected somehow during the pregnancy and if so where is this information kept?

<comment><USER15> Male fetal DNA is found in the brains of mothers.

[http://www.latimes.com/health/boostershots/la-heb-women- brai...](http://www.latimes.com/health/boostershots/la-heb-women-brain- microchimerism-20120926,0,6446716.story)

</comment></comment><comment><USER16> What if the mother is feeding a pair of non-identical twins (a boy and a girl)?

<comment><USER17> One discrete tit for each tot? Beyond that, who knows. I'd love to see this phrase turn up in an academic journal somewhere.

<comment><USER18> But they don't do that.

</comment></comment></comment><comment><USER19> I don't think the mechanism is a direct biological signaling of the baby's sex to tell the woman to produce fattier milk. It seems more plausible to me that wealthier families value boys a lot more - you see this tendency everywhere. This causes mothers to value their male children disproportionately, and the social feedback she gets probably affects her hormones as well, which would cause the milk to vary. So you see the large difference in wealthier women's milk for boys and girls, whereas the difference in poorer women's milk may not even be statistically significant.

I think if you repeat this test on different circumstances where the child is valued or not, whether boy or girl, you will find similar results that remove the sex factor.

<comment><USER20> Surely the cultural explanation doesn't extend to similar behavior found in grey seals, red deer, and rhesus macaques? Convergent evolution is always a possibility but it seems like the likelihood lies with a biological explanation vs a cultural one.

</comment></comment><comment><USER21> "These findings could have implications for formula, which could be tweaked to optimize development for both boys and girls."

As the father of a little girl, I find this sentence more ominous than was probably intended. The formula aisle is already overly complex with Regular, Iron Enriched, Omega Enriched, Soy, Low-Lactose, and No Lactose, among the many yogurt sounding ones (pre/macro/post/whatever-biotic).

However, I am worried (perhaps due to cynicism) that instead of rationally simplifying this system, it might be dumbed down to Boy and Girl formula. Though I guess there may be benefits as well. _sigh_ \- glad I'll probably be done having kids by then :D

<comment><USER22> Keep away from the formula aisle if at all possible!

</comment></comment><comment><USER23> Will the patriarchy stop at nothing to keep women down?!

<comment><USER24> Why do you think this article is about keeping women down?

<comment><USER23> I don't. I was being flippant.

</comment></comment></comment><comment><USER25> > researchers have found that milk composition changes depending on the > infant's gender

Sex. Infant's sex. Gender is rarely known at that stage.

</comment><comment><USER26> I posted on this story and the issues it raises here: [http://humanwithuterus.wordpress.com/2013/12/18/gendered- bre...](http://humanwithuterus.wordpress.com/2013/12/18/gendered-breast-milk/)

Would love your thoughts!

</comment><comment><USER27> If this result is valid, it's probably also true for other mammals that bear young one at a time. If so, it's proabably a lot easier to verify in cows than humans. Less paperwork required for experiments, for one thing.

<comment><USER28> From the article: _" These findings, published in the American Journal of Physical Anthropology in September, echo previous work that showed milk composition varying with infant gender in gray seals and red deer and with infant gender and the mother's condition in rhesus macaques."_

</comment></comment><comment><USER29> Well duh. All babys get different breast milk. There is a feedback loop between the child and the mother that modifies the milk on an ongoing basis.

<comment><USER18> I've never heard anything like that, odd they don't mention it in the article. Got any intro-level references? How does it work?

</comment></comment><comment><USER30> My wife breastfed our boy/girl twins. I wonder where that fits in?

</comment><comment><USER31> What about twins?

</comment><comment><USER32> Wow! Great info!</comment>


Herman Cain, Former Presidential Candidate, Dies at 74 - <AUTHOR> https://www.nytimes.com/2020/07/30/us/politics/herman-cain-dead.html <comment><USER2> Related discussion [https://news.ycombinator.com/item?id=23998781](https://news.ycombinator.com/item?id=23998781)</comment>


Multiagent Systems: Algorithmic, Game-Theoretic, and Logical Foundations (2010) [pdf] - <AUTHOR> http://www.masfoundations.org/mas.pdf <comment><USER2> Thanks for the book! Sure I'll learn something from it when I get time to read it.

</comment><comment><USER3> Has anyone ever played with an agent oriented language?

<comment><USER4> I have not, but I spent a lot of time looking into it. In the end I had a hard time justifying the time and technical debt required to get something like agentspeak into production. I did play around with flame[0], a C based framework (I'm much more comfortable with C than java) - I liked it.

[0] [http://www.flame.ac.uk/](http://www.flame.ac.uk/)</comment></comment>


Ask HN: Is there a physical device that works as a hardware VPN? - <AUTHOR> I'm wondering if there is some device that works as a hardware VPN such as:
Cable modem --> VPN Device --> WiFi Router.
The idea would be that all requests through the router would be routed through some remote VPN. This way users wouldn't have to configure software VPNs and/or their router's VPN. Seems like there is a market for a plug-N-play device like this. <comment><USER2> I'm not sure what scale your looking for, or do you plan to purchase or run your own VPN.

I have seen may guides to using the following devices: Raspberry Pi Ubiquiti Edge RouterX PFsense SG1000 Tiny Hardware Firewall

Those are just off the top of my head.

We also have some larger commercial units to extend our network across public networks to put remote sites on our network.</comment>


Ask HN: Home treatment options for Covid-19? - <AUTHOR> It seems that we're on track to exceed medical capacity for treatment of COVID-19.  I've seen alot of information on diagnosis and triage - but not much on how you actually treat it once you or a loved one have the sickness. I'd like to gather the supplies and/or remedies that might ease the course of the virus, and wonder if anyone has advice on what to get? <comment><USER2> I am wondering if CPAP machines that many seniors already have can be hacked to provide oxygen as well as positive air pressure. They already have a connection for an external oxygen generator but those are expensive and probably will be sold out fast. Oxygen generation is a simple process using zeolite to absorb nitrogen which is cheap, most of the complexity is in the valves and control circuitry to manage a two-cycle process where two cylinders of zeolite are alternately pressurized and exhausted. Is it possible to create a simple mechanical flip-flop valve that operates on air pressure rather than complex electronics?

<comment><AUTHOR> [https://github.com/jcl5m1/ventilator](https://github.com/jcl5m1/ventilator)</comment></comment>


Is your cell phone cooking your brain? - <AUTHOR> http://scienceblogs.com/pharyngula/2011/06/is_your_cell_phone_cooking_you.php

<comment><AUTHOR> Related article with more epidemiological detail:

[http://scienceblogs.com/insolence/2011/06/the_bride_of_the_s...](http://scienceblogs.com/insolence/2011/06/the_bride_of_the_son_of_the_revenge_of_c.php)</comment>


So you're thinking of tracking your JS errors - <AUTHOR> http://blog.meldium.com/home/2013/9/30/so-youre-thinking-of-tracking-your-js-errors <comment><USER2> Logging JS errors is _quickly_ becoming easier than you think. :)

On the spec side, we have access to the the column number and… <drumroll>… the stack trace! This took a long time, but it's in now. [https://mikewest.org/2013/08/debugging-runtime-errors- with-w...](https://mikewest.org/2013/08/debugging-runtime-errors-with-window- onerror)

Chrome already has support and.. if past release schedules are maintained, all users of Chrome should have this feature _within the next week_. Firefox already has support for the CORS behavior and is working on adding the stack to onerror.

If you want cross-browser stack traces: [https://github.com/occ/TraceKit](https://github.com/occ/TraceKit). It's used reliably by many large projects. If you want to track these in a reasonable dashboard: [https://getsentry.com/](https://getsentry.com/) Sentry even supports sourcemaps, so you can map an error of "e.a is not a function" back to the original unminified JavaScript. Also, open source.

We're turning on CORS for the Google JS Library CDN, too.

<comment><USER3> Suggesting TraceKit is pretty much:

"In order to get stack traces, you need to wrap your code in a try/catch block like above. Otherwise the error hits window.onerror handler and will only contain the error message, line number, and column number."

TraceKit doesn't do this for you; you still need to wrap in try/catch, so you might as well just do that and have the error/stack trace there.

<comment><USER4> If using jQuery, it is a few lines of code to add try/catch around the majority of your code entry points.

Go to [https://github.com/getsentry/raven- js/blob/master/dist/1.0.8...](https://github.com/getsentry/raven- js/blob/master/dist/1.0.8/raven.js) and you will see code that wraps $.event.add(), $.fn.ready(), $.ajax(), window.setTimeout() and window.setInterval() (search _helper).

</comment></comment></comment><comment><USER5> The CORS thing is a big deal. Basically it means your JS error reporting is useless (window.onerror won't report any details) if your JavaScript is loaded from a CDN, unless your CDN has CORS enabled.

If you're using AWS for your CDN, you may be in trouble currently. There's a combination of issues between CloudFront and S3 where this actually becomes a big deal.

While S3 does support CORS, it will only return the "Access-Control-Allow- Origin" header when the Origin header is passed (which only happens on CORS requests themselves). And even if you set an S3 CORS policy of "Access- Control-Allow-Origin: * " it will return a more specific header like "Access- Control-Allow-Origin: example.com", based on the request's "Origin" header. (Because of this behavior, S3 does correctly send a "Vary: Origin" header).

Now, CloudFront will cache the "Access-Control-Allow-Origin" response header, but it does so incorrectly because it doesn't respect the "Vary: Origin" header from S3.

So, that means that even if you _think_ CloudFront is returning the right "Access-Control-Allow-Origin" header, it's only doing so from some geographic locations and its based on some randomness of whether or not the 1st cache hit per node happened to have the desired "Origin" header.

I filed a ticket with AWS a few months ago about CloudFront supporting "Vary: Origin", but they haven't, yet.

Therefore, to my knowledge, it's impossible today to get decent js error reporting if your JavaScript is served from CloudFront with an S3 origin.

<comment><USER6> So somehow I've never noticed this as a problem. We get full stack traces for everything. On the other hand we use the hosted version of Sentry ([https://getsentry.com](https://getsentry.com)), but since everything is open source, we bundle their raven library ([https://github.com/getsentry/raven- js](https://github.com/getsentry/raven-js)) into our CDN served package. So window.onerror is set from the same JS as the rest of the app. I'm guessing that avoids the cross-domain issue?

<comment><USER5> My understanding is that if your website and error-producing-JS file are different domains then you'll have an issue still. I think raven-js does some other stuff regarding letting you rethrow Exceptions, which would still work, but window.onerror is probably not reporting much in most browsers. Could that be the case?

</comment></comment></comment><comment><USER7>
      "Theoretically, we could wrap every function call in a try/catch and we'd
       have an error object in the catch block. This is bad; please don't try.
       You'll have a particularly hard time with asynchronous callbacks anyways."

Couldn't disagree more with this point. Wrap the function, not the call. Something like this:

      function logExceptions( fn ) {
        return function() {
          try {
            return fn.apply( this, arguments );
          } catch( e ) {
            logException( e );
          }
        };
      }

      myFunction = logExceptions( function() {
        // do stuff
      } );

Now you just call myFunction() normally. Pretty painless.

Further, you only have to use a logger-wrapped function for your script's entry points, not "every function": the initialization method (if any), event handlers, setTimeout callbacks, etc. Since you're probably already calling non-native methods which wrap those APIs, that method can handle exception log wrapping for you, too.

For example, for event handling I call an internal on(obj, "name", function(){}) method, and on() passes the callback through logExceptions() for me.

<comment><AUTHOR> I didn't say this was impossible, just probably a bad idea. If your application is simple enough for this to work though, go for it.

<comment><USER8> But there's no need to wrap _every_ function, just the ones that can be top- level entry points. It's a very small list, if your application is well- designed.

Patch setTimeout and setInterval. Register a jQuery ajax prefilter that wraps all your ajax callbacks. Patch jQuery's low-level UI event binding function.

And you're done. I've done this in a rather large application. It works fine.

<comment><AUTHOR> Fair enough. I guess that's the pure js/jquery version of hooking into Angular/Ember's onerror. Makes sense. At least we won't need to do this for much longer though.

</comment></comment></comment></comment><comment><USER4> Getting the stack trace is usually painless if using jQuery. The large majority of code runs inside an event handler registered using jQuery, so there is a single place to put a try/catch within jQuery and ravenjs/getsentry do that. It also overrides window.setTimeout for the same reason.

The article doesn't mention my biggest problems:

* about half my reported exceptions are due to injected third party code. We use https, but browser extensions and plugins run JavaScript within your page. Some of the time it is obvious the exception is in third party code because of the script name or exception text, but even then it causes a lot of noise.

* With a single page app, we are extremely keen to monitor and diagnose communication problems. However often error logging will fail if the connection has failed. We use getsentry so that at least we are logging to a different domain, but ideally we need to store errors offline and forward them once getting online again.

<comment><AUTHOR> All good points.

Mind elaborating on the jQuery point for others? Link?

We haven't hit the other two concerns just yet but they definitely make sense. I feel that getsentry/ravenjs type products will have to offer something to filter out the noise and for offline log buffering. Both fixable, but probably not by us.

<comment><USER4> Go to [https://github.com/getsentry/raven- js/blob/master/dist/1.0.8...](https://github.com/getsentry/raven- js/blob/master/dist/1.0.8/raven.js) and search for jQuery. You will see code that wraps $.event.add(), $.fn.ready(), and $.ajax()

Search for _helper('setTimeout') and _helper('setInterval') to see how it injects exception capture for those functions.

The above cover the vast majority of code entry points if using jQuery.

</comment></comment></comment><comment><USER9> In addition to the excellent services mentioned in the article, I'd like to recommend Rollbar ([http://rollbar.com/](http://rollbar.com/)) -- we've been using them for almost a year and have come to rely on them exclusively.

Their major selling points for us were GitHub integration and filtering by user-agent/other strings (baiduspider tormented us for a while), plus their packages for logging server-side errors (we use them for Node.js). Their price point is also very generous for startups :)

</comment><comment><USER10> And I'm just sitting here, catching errors and sending them to Google Analytics as Events.

</comment><comment><USER11> A recent version of Chrome Blink enhanced windonw.onerror to provide a real Error object with column numbers as well, so you no longer need to wrap all entries into JS with a uncaughtexception handler, which is what Closure, GWT, Dart, Angular, et al do.

Combined with sourcemaps, you can get perfect deobfuscated stack traces with little overhead.

</comment><comment><USER12> I've compiled a list of JS error logging services here: [https://gist.github.com/cheeaun/5835757](https://gist.github.com/cheeaun/5835757) . I've also tried tagging which one of them uses tracekit and supports source maps, etc.

</comment><comment><USER13> V8 makes JS error logging very simple, as we see in Node.js. I've also implemented remote JS error logging for Titanium Mobile on Android (also V8) using TestFlight. JavaScriptCore has similar error handling, but only in the past year [1].

As with most past frontend JS issues, browser fragmentation is the cause. Luckily for JS, standards move much quicker these days. With the plethora of mobile and server logging SaaS companies popping up, the browser won't get left far behind.

However, as I've found with mobile, implementing even a half-working service with currently available technology is far better than debugging otherwise.

[1] [https://bugs.webkit.org/show_bug.cgi?id=40118](https://bugs.webkit.org/show_bug.cgi?id=40118)

</comment><comment><USER14> If you're using Q, you get long stack traces [1] for debugging asynchronous behavior! That way you can follow the entire path of an exception, through multiple callbacks. Q also wraps every function with a try/catch statement, and will push caught exceptions into the error pipeline [2].

[1] [https://github.com/kriskowal/q#long-stack- traces](https://github.com/kriskowal/q#long-stack-traces) [2] [https://github.com/kriskowal/q#handling- errors](https://github.com/kriskowal/q#handling-errors)

</comment><comment><USER15> If you're using Angular, it is possible to patch the error handler service and augment it with additional info like the expression that was the cause, scope erc. That's what we've done at [https://starthq.com](https://starthq.com)

We also have browser specific code to prettify the stack traces. We push the errors to our server and from there to Sentry and that works like a charm! In fact it's so good that we've used it to report issues to third party script providers such as Clicky analytics about errors in their scripts.

</comment><comment><USER16> Is it just me, or does anyone else think the way CORS works right now is completely bass-ackwards? We have a page served by Host A that wants to access resources on Host B. Why is it that Host B has to allow this and not Host A? If I compromise a script on Host A, of course I'll also add the needed headers in the reply by Host B! Isn't it a lot more sensible that Host A should include a header that says "you are allowed to also download resources from Host B"?

<comment><USER17> Actually, it only makes sense as it works right now. When you are a developer on host A and decide to include a script, then you have already figured out that script is safe to include, so no bookkeeping is necessary. If a hacker has gained access to host A they can run any code they want, so there is no reason to prevent inclusion of scripts from host B. However, the developer of host B might have designed their resource so that it provides privileged user data based on a cookie. If it can be loaded into the page of host A it would give the developer (or hacker) of host A access to the privileged info of all users that frequent host B. This is why the developer of host B must explicitly publish a resource for inclusion on foreign pages.

</comment></comment><comment><USER18> Another good reason for compiling to JavaScript from a higher level platform.

With GWT you get complete and accurate stacktraces straight into the Java codebase. Catch it, send it to the backend for logging. Most client-side JavaScript errors are noticed and fixed as soon as the first user has encountered them.

This even works with heavily obfuscated/minified JavaScript, thanks to the symbol maps output by the GWT compilation, which can be used to deobfuscate any stack trace.

Here is an example from our HTML5 game[1], 100,000+ lines of code built entirely in GWT:

Client sees this:

    		com.google.gwt.core.client.JavaScriptException:
    		 stack: TypeError
    		    at pHc (AAC650305790C67B7708D7A391EFF482.cache.html:4929:343)
    		    at Object.wIc [as Nc] (AAC650305790C67B7708D7A391EFF482.cache.html:5065:16814)
    		    at Object.Af [as Mc] (AAC650305790C67B7708D7A391EFF482.cache.html:5038:5333)
    		    atAAC650305790C67B7708D7A391EFF482.cache.html:3558:58
    		    at Hh (AAC650305790C67B7708D7A391EFF482.cache.html:2921:29)
    		    at Kh (AAC650305790C67B7708D7A391EFF482.cache.html:4588:59)
    		    at AAC650305790C67B7708D7A391EFF482.cache.html:3913:45
    		 type: type_error
    		 arguments: f,
    		    at Unknown.pHc(Unknown Source)
    		    at Unknown.wIc(Unknown Source)
    		    at Unknown.Af(Unknown Source)
    		    at Unknown.anonymous(Unknown Source)
    		    at Unknown.Hh(Unknown Source)
    		    at Unknown.Kh(Unknown Source)
    		    at Unknown.anonymous(Unknown Source)

This is sent to the server, deobfuscated and logged like this:

    		2013-01-10 21:07:04 ERROR   ExceptionLogCommandCommand...ommand.execute(ExceptionLogCommandCommand.java:44): Deobfuscated client-side exception:
    		java.lang.IllegalStateException: Player not in line-of-sight for shot (viewport=[[887, 638, width/height=800/560]], player x/y=[1413, 876])
    		    at java.lang.IllegalStateException.IllegalStateException(IllegalStateException.java)
    		    at webworks.engine.client.player.Enemy.shootGetShotPosition(Enemy.java)
    		    at webworks.engine.client.player.AbstractPlayer$10.perform(AbstractPlayer.java)
    		    at webworks.engine.client.player.AbstractPlayer.$animate(AbstractPlayer.java)
    		    at webworks.engine.client.WebworksEngine$5.perform(WebworksEngine.java)
    		    at webworks.engine.client.WebworksEngine.$render(WebworksEngine.java)
    		    at webworks.engine.client.WebworksEngine$25.doRun(WebworksEngine.java)
    		mozilla/5.0 (windows nt 6.0) applewebkit/537.11 (khtml, like gecko) chrome/23.0.1271.97 safari/537.11

With this log entry, most of the time the error can be found simply by looking at the code for a few seconds.

[1] [http://www.webworks.dk/enginetest](http://www.webworks.dk/enginetest)

</comment><comment><USER19> This is one reason that I've been very excited/anxious for [http://trackjs.com/](http://trackjs.com/) to launch.

</comment><comment><USER20> Javascript doesn't really have good tooling but at least if you don't like it, there are dozens of alternatives, just like in any other software space.

What I just said in the previous sentence is (NaN === NaN).

<comment><USER21> What alternatives to JavaScript are there for browser-side scripting? Even things like CoffeeScript and Dart only translate into JavaScript and still use its runtime.

We just have to continue to improve the tooling.

<comment><USER22> What he said in his first sentence is false. Thus, there is no alternative.

It's a quite strange way of writing a sarcastic comment, but it does agree with you.</comment></comment></comment>


Read Then Burn - <AUTHOR> https://www.readthenburn.com

<comment> grey-area Fun idea, though I don't think I'd trust it with anything important, as obviously it requires trusting the website owners were and are sincere and uncompromised, and all the code they include.

If you're concerned about giving at least the impression of privacy though, your pages should not contain third party, _and_ externally hosted js -

[https://platform.twitter.com/widgets.js](https://platform.twitter.com/widgets.js)

[https://platform.stumbleupon.com/1/widgets.js](https://platform.stumbleupon.com/1/widgets.js)

Given the number of sites this sort of js is included on, it must be a huge target now for people interested in breaking into websites and stealing info. If even one of the smaller social networks like stumbleupon was hacked you could take over and keylog quite a few sites just by adding something to the js, then once you have admin access, you have the site.</comment>


Chromebooks now available on Amazon ($350 - $450) - <AUTHOR> http://www.amazon.com/chromebook

<comment><USER2> I'm really fairly confused: does Google, or any of the partner manufacturers, actually think these will sell at this price?

Or maybe this is a bid for the enterprise? I'd imagine they're the only group for whom a completely managed laptop is worth such a price premium.

<comment><USER3> I doubt enterprise will touch these. They have even harsher application dependencies than consumers. Even in the niches where it would work (ie. travelling salesmen), enterprises buy hardware in bulk so they'd probably just keep buying what they buy for everybody else.

<comment><USER2> That's what I would have thought.

Which leaves the question: what consumers do they think want these?

</comment></comment></comment><comment><USER4> These have been on sale for weeks?

<comment><AUTHOR> Entirely possible - I just received the email from chromebook team today.

"You asked to be notified when Chromebooks became available. We're pleased to inform you that the Samsung Chromebook Series 5 is here: a fast, simple, and secure way to get online."</comment></comment>


Stockrow.com – US financials data - <AUTHOR> https://stockrow.com <comment><USER2> This is nice -- simple, clean interface, presenting lots of useful data and visualizations.

Does anyone know where they source their data from? I can't find anything on their page.

<comment><AUTHOR> Stock prices are from Quotemedia and fundamentals from Sharadar</comment></comment>