Why Philosophers Should Care About Computational Complexity - <AUTHOR> http://www.scottaaronson.com/blog/?p=735 <comment><USER2> _A given Turing machine M either accepts, rejects, or runs forever (when started on a blank tape)... [W]hich one it does is an objective fact, independent of our formal axiomatic theories, the laws of physics, the biology of the human brain, cultural conventions, etc._ (p. 43)

Nice way to put it. As Franzen points out in "Inexhaustibility", although non- logicians sometimes find it puzzling, the above is related to what mathematicians mean when they say that a statement is _true_ without further qualification. For instance, take Gödel's first incompleteness theorem. It states that if _F_ is any consistent formal system capable of proving statements about whether or not arbitrary Turing machines halt, then there are _true_ statements which cannot be proved within _F_. (Here, _consistent_ means that it's not possible within _F_ to prove both a statement " _S_ " and its negation "not _S_ ".)

In the same sense, its _true_ (as Aaronson wrote in "Logicians on Safari") that "there's a finite (and not unimaginably-large) set of boxes, such that if we knew how to pack those boxes into the trunk of your car, then we'd also know a proof of the Riemann Hypothesis."

</comment><comment><USER3> They already do. Incompleteness Theorem ("some logical statements are true but are unprovable", e.g., "this program will terminate" for some arbitrary programs a.k.a. the Halting Problem) is one of the most significant achievements in logic.

Here's philosophers' take on Kurt Godel:

<http://plato.stanford.edu/entries/goedel/>

I am, however, curious as to how other problems in computational complexity figure in philosophy, e.g., P vs. NP completeness. Wish I had the time to read the essay.

<comment><USER4> I haven't read the paper, but here's one example I've seen. Assume for the moment that the universe is closed, complete (there is nothing but our universe), and deterministic under the hood. Obviously, nobody in the universe has free will, right? Because it's all closed and all outcomes are predetermined.

But maybe that's not a useful definition of free will. The conventional, fuzzy definition of free will has an omniscient narrator in it; "I do not have free will if the omniscient narrator knows in advance everything I will do" is a reasonable expansion of the conventional idea. But in my hypothesized universe, there _is_ no omniscient narrator. There are only various entities with various degrees of computational power, with a varying but rather quantifiable amount of information that any entity can obtain about any other.

Suppose it can be demonstrated that it is computationally infeasible for any entity due to being too complex to ever predict the actions of any human-sized (or greater) other entity, even if granted all the remaining resources in the universe to compute the actions. Or suppose it is demonstrated to be quite easy. Either way, that would be an interesting philosophical contribution, no?

(I'm just sketching the idea here. I'm not trying to defend it or attack it. Oh, and one of the foundations of philosophy is that there is never One True Definition; all loaded terms in this post are ultimately ill-defined, and I've avoided the distraction of even beginning to nail them down on purpose.)

<comment><USER5> Your suggestion confuses an epistemic limitation with a metaphysical one. Just because no one knows what we're going to do next doesn't mean there isn't a fact of the matter about it.

While the idea of God looking down on us from on high is a compelling story, if you take God away but leave determinism it doesn't do anything to resolve the problem: our actions are still pre-determined and cannot be changed.

Of course, whether or not that makes us _free_ is a further question. A compatibilist [1] would claim that we are.

[1] <http://plato.stanford.edu/entries/compatibilism/>

<comment><USER4> "Confuses" is one way to read it. "Shines a spotlight on the intersection of" would be a somewhat friendlier way to read it. Is a fact that can't be known, even in theory, even a sensibly a "fact"? I deny your implicit claim that that isn't an interesting question because the answer is transparently obvious.

Epistemology becomes much richer when fed with mathematical proofs of statements like this, and some older snap answers at least have to be reconsidered.

<comment><USER5> I don't think it's by any means _uninteresting_ , and I agree that complexity theory has a role to play in enriching epistemology. That's why I said elsewhere in this discussion that I think this kind of work is important.

However, it's not in any way obvious that there are metaphysical implications to the limits this sort of result would place on knowledge. Facts are (for present purposes) simply to be identified with physical states of affairs. If some physical state of affairs is unknowable (and "System S will be in state R at time T" certainly _looks_ like a physical state of affairs), does that mean it does not (or will not) actually obtain? I have a hard time seeing how one could make that argument, although of course that shouldn't stop you, if you think you have a good angle!

To address the particular example under discussion: if you take free will to consist of the impossibility of predicting an agent's actions and conclude that because this prediction is impossible, we are free, you still need to provide a further argument that your definition of free will is the correct one.

I'm not prejudging whether or not you could come up with a convincing argument to that effect—it might well be possible. But to my mind, the point of the omniscient narrator example is to add determinism to the system: because our actions are known in advance, they can be known in advance; if they can be known in advance, they must be determined. I take this to be the implicit argument when people suggest that we're not free because God knows what we will do.

Obviously there are different ways in which we can understand the modalities of time, and I won't try to pretend that this isn't a contentious area.

</comment></comment></comment></comment></comment><comment><USER6> This is basically aimed at analytic philosophers. Continental philosophers generally aren't interested in this sort of thing.

<comment><USER7> What evidence do you have for this?

</comment></comment><comment><USER8> It's interesting that one of the references Aaronson cites [63] is the pg essay "How to do philosophy" <http://www.paulgraham.com/philosophy.html>

</comment><comment><USER5> This looks fascinating, and in yours truly is guaranteed at least one reader, once I have some time to devote to it. I think there's a lot of room for interesting work in this area.

</comment><comment><USER9> The problem with Godel and friends is that they point to the limits of rationality. Without a transcendent rationality (and morality) upon which to discurse, philosophers are out of a job, so to speak. If you use logic to understand everything, the last thing you want to deal with is somebody telling you the limits to logic. So they blow him off.

At least I think the above is true for "analytic" philosophers. The "continentals", on the other hand, have been engaging in an extended _attack_ on transcendent rationality since Nietszche who said, to paraphrase, that every transcendent metaphysics was an attempt to justify a morality, and every morality was facilitated a (usually inarticulate) "will to power." (This line sort of starts with Hegel, who posited that rationality emerged from history and the development of a collective human spirit, but wasn't "out there" before that). Godel seems like ammunition for these guys, but I don't think they have picked him up much. I guess if you are anti-rationalist, the last thing you read up on is advanced logic, even if it is so advanced it comes to its own frontier.

<comment><USER10> I believe Alain Badiou might be an exception here.

<http://en.wikipedia.org/wiki/Alain_Badiou>

<comment><USER11> The book "The Mathematics of Novelty" seems like a pretty good introduction to Badiou. As with most non-fiction published by re.press it is creative commons: [http://re-press.org/books/the-mathematics-of-novelty-badiou%...](http://re- press.org/books/the-mathematics-of-novelty-badiou%E2%80%99s-minimalist- metaphysics/).

</comment></comment></comment><comment><USER12> I've always considered philosophy as a sort of the mind's struggle for its own life. The introspective mind somehow can't validate itself without somehow having the absolute last say about something.

Given this track, a philosophical mind will produce a lot of thoughts, models, and theories of how anything that already exists _could_ exist in the first place. That is itself an interesting mind-game that in some cases might even produce an insight that is applicable to something real, but generally that's where it should stay.

The mind can't think itself into existence, even if it wants to believe it can.

If it does the result bears resemblance to as if someone would try to describe forest but only be allowed to draw straight lines in one color. At best it could be exemplary line art, at worst it's just ridiculous and childish and most people will turn the other way.

</comment><comment><USER13> It seems nobody has mentionned Gregory Chaitin[1] yet, and in my opinion it's kind of mandatory when discussing this very topic. So now it's done :-). I like his work a lot. His not really working on this subject anymore (now he's developping a new field called metabiology which is also fascinating but not very relevant here) but he used to work on Algorithmic Information Theory and he wrote a lot of books and essays (you can find almost everything on his webpage) on the subject we're discussing here. _The Limits of Mathematics_[2] might be the most relevant to Hacker News users.

[1] <http://www.cs.umaine.edu/~chaitin/> [2] <http://news.ycombinator.com/item?id=1725936>

<comment><USER2> _It seems nobody has mentionned Gregory Chaitin[1] yet_

With good reason. The logician Torkel Franzen said it well in "Gödel's Theorem: An Incomplete Guide" [Chapter 8, p 148]: ``Chaitin's claim to have discovered "the amazing fact that some mathematical statements are true for no reason" has no apparent content, but seems rather to be based on the general associations surrounding the word "random".''

</comment></comment><comment><USER14> Unabridged work posted on the Electronic Colloquium on Computational Complexity: <http://eccc.hpi-web.de/report/2011/108/>

</comment><comment><USER15> one interesting perspective on complexity is that of Ashby and his law of requisite variery. [http://en.wikipedia.org/wiki/Variety_(cybernetics)#The_Law_o...](http://en.wikipedia.org/wiki/Variety_\(cybernetics\)#The_Law_of_Requisite_Variety)

this work was later manifested in the work of stafford beer creating a control center in chile during the 70s.(<http://en.wikipedia.org/wiki/Project_Cybersyn>).

</comment><comment><USER16> I think irreducibility is well received in philosophy. Evolutionary Biology not so much for political reasons. Sure there are are plenty of models that incorporate emergent phenomena but it's a heated area.</comment>


Single purspose app or Multi purpose app? - <AUTHOR> Which one is better and why? <comment><USER2> Same situation right now, do i focus on the thing i think is the most important or do i focus on that but build services around that integrate several other semi related things.

I think the latter could earn more per person, while i think the first would probably be way easier to advertise and gain users with.</comment>


Hack your brain: How to hallucinate with ping-pong balls and a radio - <AUTHOR> http://www.boston.com/bostonglobe/ideas/graphics/011109_hacking_your_brain/ <comment><USER2> I used to be able to do this when I was like 4 years old, just by having my eyes closed for a few minutes. I told my mom that I was seeing things when I closed my eyes and asked her what it was. She acted very worried so I never mentioned it again.

By a year later the effect went away and I've never experienced it since- But I kinda remember what it was like.

</comment><comment><USER3> I tend to hallucinate (mostly classical) music when I am about to fall asleep.

<comment><USER4> This happens to me as well. Sometimes I also hear random disconnected sounds: a bell, pots clanging, voices, etc. There have been many nights where I've actually struggled to sleep through all the cacophony.

<comment><USER5> In "Surely you're joking, Mr Feynman", Feynman went over a few experiments he did to notice what happens when you're falling asleep when he was an undergrad. He concluded that your thoughts become more and more random and flooded as you get closer to actual sleep, until your brain gets overwhelmed and passes out.

<comment><USER6> >He concluded that your thoughts become more and more random and flooded as you get closer to actual sleep, until your brain gets overwhelmed and passes out.

At one point when I had trouble falling asleep in less than 1/2 an hour, I used the reverse to fall asleep quicker: I'd guide myself into thinking outlandish things, then my brain would naturally progress in this fashion until I fell asleep.

<comment><USER7> This has worked for me in the past. Though I can never repeat it reliably. Given enough stress for the following day, my thoughts will gravitate back to what needs to get done.

</comment></comment></comment></comment></comment><comment><USER8> None of those look fun or useful. Talk to your friendly local dealer and he'll be able to provide something better.

<comment><USER9> You'll learn more about sober, typical perception through these than you will on drugs, the carpet bombing approach to psychedelia. And it's that exploration that's most interesting for me.

<comment><USER10> ::Grabs popcorn and dons flamewar armor.::

I don't disagree with you, but "carpet bombing" is going a little far. I don't think psychedelic drugs are the best way to explore one's mind for most people, but they are interesting and can be valuable in some circumstances. Unfortunately, we as a collective know very little about how to use them, and individuals generally know less.

<comment><USER11> _explore one's mind_

This is the big lie of psychs, that they allow you to "explore your mind" as if somehow you're not fully understanding it while sober (and through meditation).

Psychs rewire how the brain handles and deals with sensory input, so that when you do them you're not exploring the mind you have while sober, but entering into a completely different "mind" based on distorted perception.

It's like thinking you're exploring new rooms in your own home when in fact you're 9 blocks away checking out a house that's entirely different in structure and form. Of course that adventure will bring in fresh new perspectives, but in no way does that help you discover more about your own home.

<comment><USER9> I don't think that's correct: one can still be mostly lucid while having the drug affect some part of their mind. You _can_ sometimes bring things back.*

Often it's not really sensory at all; it seems to work at a higher, conceptual level. For example, I once looked in a mirror and saw myself, but recognized different people, with different personalities, my mother, my siblings, my different personalities.

I looked out into a room, and I saw all the elements, but my experience of it was flat, as if someone took a picture and laid it out on paper. Then the shading in the picture implied lighting, which quickly implied depth. Objects rotated into consciousness. I saw a tree, and then suddenly the existence of leaves and branches screamed out to me, as if to say "we are entities too! we are not simply parts of the tree! we are objects of our own." A friend of mine was standing near, but still. At a conceptual level, my perceptual experience of her was of an extremely accurate _statue_ of her. As in "my, what a life- like Sarah __." And then she moved, and she was animate again, a real person.

A friend of mine studies perception. He tells me there's a lot of evidence for these kinds of 'perceptual layers,' and that a lot of the subconscious visual classifications that I was experiencing. Self, not self. Person, not person. Animate, not animate. Object, not object. Flat, not flat. One expects it's the sort of thing that we do naturally, for many other sorts of things. Male, female, old, young, intelligent, dim, aware, tired, happy, sad, etc. And it's the sort of thing that neural networks can do, too.

So I definitely think that there are things that you can bring back. I think if you try hard, you can hold on to the experience, and see how much of it makes sense in the real world. But I'm not sure this is the experience of most people. I hear lots about people seeing pretty colors.

* Note, all this happened on half a hash brownie, alone. This experience suggest that I stay away from anything harder.

 __Name changed to protect the innocent.

</comment></comment></comment></comment></comment><comment><USER12> I hallucinated after pulling two all-nighters in a row in college. I ended up being awake for three days and two nights and ended up seeing that the world was just _beautiful_. Spent hours in a park looking at blades of grass and then a long time examining the surface of an orange.

</comment><comment><USER13> I think I remember seeing a much better set of procedures, involving a special set of glasses and maybe some other equpiment that you had to build, which would actually lead to something that wasn't just a fun party trick.

Oh, this is it: <http://www.makershed.com/ProductDetails.asp?ProductCode=MSBM>

Also, if you want a much more painful way of achieving hallucination, experience a traumatic situation repeatedly, which is clearly preceded by a distinct sound. From personal experience I can say you will occasionally hallucinate the sound in situations where it would never sensibly occur.

<comment><USER10> You can buy "mind machines" for about $100. Or you can use get the sound component, at least, out of your computer using an online beat generator.

<comment><USER14> Just go to the App Store and buy a Binaural Beats app for a couple of bucks instead

</comment></comment></comment><comment><USER15> Ah, ganzfeld. It reminds me of _Altered States_ , a movie about sensory deprivation that went horribly wrong. I was fascinated by this movie when I was a kid.

<http://en.wikipedia.org/wiki/Altered_States>

<http://www.youtube.com/watch?v=MbYT3UclhNY> (trailer)

<http://www.youtube.com/watch?v=LTqFXfn3kdo> (few scary scenes)

</comment><comment><USER16> I'm trying this as soon as I get home.

</comment><comment><USER17> Is there anyone who doesn't know this?

Who hasn't relaxed with some classical music and their eyes closed, while their brain fires off pseudo random pretty imagery?

</comment><comment><USER10> There's nothing special about the ping-pong balls and radio. These are the effects of sensory deprivation, which can be intense if it's done right. Most interesting states of consciousness involve sensory deprivation or overload at root, including those induced by psychedelics. For example, sleep occurs most readily in partial sensory deprivation, and many forms of meditation likewise involve sensory deprivation.

Regarding the role of the radio static in this experiment, it's there to produce white noise. It's nearly impossible to drown out all noise. At 15 dB, you'll hear your heartbeat. However, the brain at rest cancels out white noise up to about 70 dB, so you can create essential soundlessness in a moderate quiet environment.

Sensory overload can be fun, too. I recommend listening to music on headphones around 80-85 dB, with your eyes shut and a blindfold on. You want the music to be just loud enough that it sounds like it's coming from within your head, but not so loud as to stimulate adrenal responses (or damage your ears).

Also, binaural beats are pretty cool. You can induce altered states of consciousness pretty easily with these technologies.

<comment><USER18> > Also, binaural beats are pretty cool. You can induce altered states of > consciousness pretty easily with these technologies.

For anyone interested in this see sbagen: <http://uazu.net/sbagen/>

<comment><USER19> beware looking for this on youtube; youtube is mono =)</comment></comment></comment>


Julian Assange awarded Sydney peace medal - <AUTHOR> http://news.smh.com.au/breaking-news-national/julian-assange-awarded-sydney-peace-medal-20110202-1ad7y.html <comment><USER2> I won't comment too much on Wikileaks in particular, there's enough discussion on next to every other part of the internet.

As an Australian however I will note how appalling the federal support from Australia has been. Our Prime Minister Julia Gillard called Wikileask "an illegal act" (I'm no lawyer so I won't question it but the Attorney-General and hundreds of lawyers came forward saying Wikileaks has broken no Australian law). She then further suggested that his Australian passport should be cancelled!

I don't feel the Australian passport is something to be retracted. If we were going to retract it for illegal acts there are far worse criminals holding an Australian passport. Luckily the act of cancelling his passport is not in the Prime Minister's hands but in the Foreign Minister's hands and he has said he is in fact in support of Assange.

As such I'm glad he's getting at least a little recognition, especially as the Sydney Peace Foundation was set up within the University of Sydney, my university.

[1] <http://en.wikipedia.org/wiki/Julian_Assange#Support></comment>


Benefits of Running for Entrepreneurs and How Exercise Relieves Stress - <AUTHOR> http://under30ceo.com/7-benefits-of-running-for-entrepreneurs-and-how-exercise-relieves-stress/

<comment><USER2> I do mixed martial arts every single day not because I love exercise but due to joint / weight problems. I have not lost a pound but the health benefits are amazing.

You have more energy. People want to go home and relax to do it all over again. If you workout, you have the energy to get home and start working again. It really has a profound impact on your burnout / mental health.

<comment><AUTHOR> Completely agree. I find the endorphin rush from running to be addictive. Helps give me MORE energy and keep my attitude positive even when work is getting me down.</comment></comment>


Amazon delivery drones could be in the air within a year - <AUTHOR> http://www.engadget.com/2015/06/17/amazons-delivery-drones-could-be-in-the-air-within-a-year/

<comment><USER2> I still remember the first time this came up and people were betting that Amazon is trolling everybody. In the same time, a far far away country:

[http://www.bbc.com/news/technology-31129804](http://www.bbc.com/news/technology-31129804)

It is good to see that drones can be used intelligently for everybody's benefit. Hello faster delivery, good buy lost (stolen) items.</comment>


RoR in the browser (Heroku + Code-academy) - <AUTHOR> http://codelearn.org/

<comment><USER2> Hi,

This is Hemanth , Founder at Codelearn. We had unprecedented spike in our traffic this morning. Thanks very much for trying us out.

frank confessions :

1\. We did not expect that codelearn will get posted on hackernews, leave alone make it to the front page!.

2\. We wanted a smaller audience to try it out first before releasing to a larger audience at hackernews .

3\. We have been working on this only for 2 months now and there are lots of rough edges, some of them are really silly, like making the rails environment production and ideally we should fixed these small things.

4\. We are working to fix these problems and will post a message here as soon as we are done.

5\. Some of you have pointed that there were Grammatical errors in the copy. We understand that it is important, but we did'nt expect such a large audience.

I would like to reiterate my gratitude for the support .

warm regards hemanth

<comment><USER3> I would like to know a bit more about the architecture behind it.

When 1000 users are coding together some RoR app, how do you guys execute that many behind on your server ? I can understand that file browser and all can be done with HTML5 APIs, but then on execution you have to take the entire app (controllers, models, views, asset pipeline, etc. etc.) on the server execute them, get the output.

Are you guys going to run a lot of web server instances then (maybe 1 per user)?

Would love to know if you got no problem with sharing. Just for knowledge :)

Cheers and good luck with it!

<comment><USER2> We would definitely write a big blog post on it. Right now I can say we had about 200 users on just a EC2 micro instance. We dint expect lot of traffic and users. and I have to run to do damage control.

</comment></comment></comment><comment><USER4> I know I'm just nitpicking, but the grammar in the title of the video ("_Whats_ the best way to learn coding?") kills my confidence. Admittedly that isn't indicative of the quality of the product but it's something best avoided.

I spend my summer teaching high school students to code, but I doubt this resource would help at all. To be honest, I'm not sure what the target audience is for this. The tutorial assumes knowledge of Unix (otherwise you're copying commands such as mv, cd, touch, ...) without explanation, meaning it's not necessarily about coding anymore. Yes, knowledge of the Unix command line is important, but that complexity should either be approached explicitly or hidden away, especially with a tag line "the best way to learn coding". Coding is quite independent of the OS you're using.

I'd also question using RoR as "the best way to learn coding". This is nothing against the framework, simply the complexity and the amount that's magically set up for you defeats or complicates the learning process. If they really want to go with that tag line, I'd be more specific -- something like "the best way to learn RoR/webapp coding".

There's also a lack of information on the CodeLearn site. Is it a pay service after the beta ends?

<comment><USER5> Speaking from personal experience, a large MVC framework like Rails is horrible for learning coding. I tried to learn Django at the same time I learned Python and my head exploded with all the conventions you try to learn at the same time. Flask provided a much better start. There is a direct coupling between query and response, and the web-app is but a thin layer around the basic language.

In the Ruby world, this would mean starting with Sinatra instead of Rails. The added benefits of MVC only become apparent in larger projects.

Learning this kind of stuff in the browser is a great idea though.

</comment></comment><comment><USER6> the slight irony here being this was something you could do with heroku when they launched in 2007

<comment><USER7> Dejavu! :)

</comment></comment><comment><USER8> I signed up for the site and got the error message below. I really like the idea of what they're doing, but if they're going to be teaching rails, shouldn't they know better than to show all that information to users?

ActiveRecord::StatementInvalid in Devise::RegistrationsController#create SQLite3::BusyException: database is locked: commit transaction

Rails.root: /home/ubuntu/codelearn

Application Trace | Framework Trace | Full Trace

<comment><USER9> This is typically a sign of having the SQLite DB open in a DB browser such as SQLite DB Browser.

I do agree with you on this point though. Hide this type of information behind a user-friendly error page.

<comment><AUTHOR> agree with you on the fact that this needs to be abstracted. however, i guess its their pre release beta version, so work can be expected.

</comment></comment></comment><comment><USER2> Looks like the db lock error was transient (due to large traffic) and now people are able to sign up. So pls try again now, In case you still face the error, please mail us at firstname.lastname@example.com, and we would mail you once we have upped our capacity.

</comment><comment><USER2> We had to take the site down. We have a few issues, we will fix them and inform you when we are up!. Meanwhile pls drop us a mail at firstname.lastname@example.com if you are interested to sign up and we will revert to you when we are up.

</comment><comment><USER2> Hey,

We have taken down the site. Please leave your email ids on the site. We will get back to you ( in a couple of days), once we are up.

hemanth

</comment><comment><USER10> The videos aren't loading because Dropbox, where they're valiantly attempting to host them, is 509'ing them.

<comment><USER2> Really sorry. Moved it to youtube!. Please check now

</comment></comment><comment><USER11> Tried to sign up, received the following error:

NoMethodError in Devise::RegistrationsController#create

<comment><USER2> so sorry. Can you send us a mail at email@example.com . we will revert as soon as we have upped our capacity.

We are not able to see this error and we see that some people are able to sign up and some are facing the error.

This is due to high traffic , just a guess. Sorry for the inconvenience.

</comment></comment><comment><USER12> if you want to see everyone's email address

$ cd ..

<comment><USER2> We have fixed this , by changing permissions. Sorry for the trouble

<comment><USER12> okay that's good. is that why I'm having trouble logging in at the moment? the console is telling me

No directory, logging in with HOME=/

</comment></comment></comment><comment><USER12> you can't even signup b/c you run into an error

</comment><comment><USER13> ERRRRRRRRROR</comment>


UC team discovers rare warrior tomb filled with bronze age wealth and weapons - <AUTHOR> http://magazine.uc.edu/editors_picks/recent_features/warrior_tomb.html <comment><USER2> Already discussed before:

[https://news.ycombinator.com/item?id=13328148](https://news.ycombinator.com/item?id=13328148)

[https://news.ycombinator.com/item?id=10454066](https://news.ycombinator.com/item?id=10454066)

</comment><comment> aurora- Basically they found a tomb of a warrior buried on the mainland, and the manner of his burial (specifically the positioning of weapons/jewelry etc.) indicates that the mainland-based Mycenaeans were strongly aware of Minoan culture, and it's likely that the two cultures intermingled and may have together "shaped the culture of classical Greece".

This contradicts previous assumptions that the Mycenaeans were essentially barbarians compared to the Minoans, and had no real impact on anything important.

<comment><USER3> I would refute that this is merely a warriors grave. It was on the Palace of Nestor, and several gold pieces were buried with him. Most likely a king or his lead warrior.

And it was already found 2015. Wikipedia has it already: [https://en.wikipedia.org/wiki/Palace_of_Nestor](https://en.wikipedia.org/wiki/Palace_of_Nestor) with a link to an older longer article: [http://www.smithsonianmag.com/history/golden-warrior- greek-t...](http://www.smithsonianmag.com/history/golden-warrior-greek-tomb- exposes-roots-western-civilization-180961441/)

</comment></comment><comment><USER4> I had to find a readable writeup: [http://magazine.uc.edu/editors_picks/recent_features/warrior...](http://magazine.uc.edu/editors_picks/recent_features/warrior_tomb.html)

</comment><comment><USER5> This article is total crap. It's super long and at half it's length it hasn't yet told me how this flipping tomb has upended what we thought we knew about western civilisation.

Jo Marchant is an awful writer and should probably be doing something else for a living.

<comment><USER6> _Jo Marchant is an awful writer and should probably be doing something else for a living._

There are many of people who enjoy long form articles and who read this sort of thing very happily. The author is writing for them, and not you.</comment></comment>


Google Cloud Is Down - <AUTHOR> https://status.cloud.google.com/ <comment><USER2> I guess 2023 came early.

<comment><USER3> I don't get why they don't just host this on AWS, it would have far better reliability.

</comment></comment><comment><USER4> Hello folks, this is @ahmetb from Google. Our teams are currently investigating and hope to have it resolved soon. From what I can tell, this appears to be a regional network issue for customers around Bulgaria (and I've seen Turkey reported online, as well). It seems to have been mitigated, if you're still hitting this outage, it would help mentioning where you're connecting from.

</comment><comment><USER5> What am I missing? Their status page says "This is fine".

<comment><USER6> This is what happens when a status page becomes a marketing tool that you can use in a powerpoint presentation in order to assess "reliability" when choosing a vendor instead of something that you can actually rely on for monitoring purposes.

</comment></comment><comment><USER7> This was posted half an hour ago and the services are already up. Why do people keep posting all these "<service> is down"? We know the Internet works on best-effort, so these posts are completely worthless unless there's something major going on.

</comment><comment><USER8> It shows a fiber cut in Bulgaria: [https://status.cloud.google.com/incident/cloud- networking/19...](https://status.cloud.google.com/incident/cloud- networking/19023)

</comment><comment><USER9> Good at making weirdo awesome internal tools that can scale incredibly and solve problems like BigTable/Kubernetes but then suck at delivering it as a service to those outside of Google.

Amazon/Microsoft figured it out already.

</comment><comment><USER10> Everything google is down here. Great, my phone will blow up from alarms any second now...

Edit: This is trying to access it from Bulgaria, I have no issues from my servers in Germany.

</comment><comment><USER11> It is down in some regions. I can access only with US VPN.</comment>


3 lessons in solving stupid engineering problems - <AUTHOR> http://frontendcollisionblog.com/javascript/2015/08/23/solving-stupid-problems.html

<comment><USER2> tldr; understand your tooling and read the docs.</comment>


What It's Like to be Recruited - <AUTHOR> http://codebrief.com/2011/06/what-its-like-to-be-recruited/

<comment><USER3> "As I write this, all in all I have received: 266 emails and 96 voicemails. This roughly equates to 12.7 emails and 4.3 voicemails per workday."

I just went through this myself and it was nuts. The phone rang from 8 am - <USER2> pm almost every 30 minutes for a week when I updated my resume on monster. My skills are back-end Ruby and SQL, both seemed to be high in demand in Chicago last month. I didn't capture detailed notes like you, but I wish I had.

"For the first week, I actually answered all incoming calls, but this eventually became unmanageable. I used the opportunity to hear them out and also sometimes give them a reverse pitch on GroupTalent for feedback."

Ha! I did the same pitching my start-up Vouched ( <http://getvouched.com> ) and doing impromptu Lean Startup style customer interviews. There is quite a range of talent and process in the recruitment industry. Some are real professionals, others are just playing on volume. I spoke to one recruiter who makes around 70 calls a day to get 3 possible candidates. The reasonable ones called 20 people at most and actually tried to develop relationships instead of dialing for dollars.

It's an interesting space, or as Charlie O'Donnell put it... a bad neighborhood. [http://www.thisisgoingtobebig.com/blog/2011/3/21/five- reason...](http://www.thisisgoingtobebig.com/blog/2011/3/21/five-reasons-why- the-job-space-is-a-bad-neighborhood.html)

Best of luck to you.

<comment><USER4> Ruby has been in ridiculous demand in Chicago for at least a year. I blame Groupon. :) They've hired big chunks of three or four consulting shops and are building their own internal teams.

One of the Obtiva owners (consulting shop) wrote: [http://nuts.redsquirrel.com/post/2680658687/chicagos-ruby- de...](http://nuts.redsquirrel.com/post/2680658687/chicagos-ruby-developer- crisis)

<comment><USER5> In Boston, it is absurd for Rails developers also.

It doesn't help call volume-wise that "Quantronix" seems to be outsourcing calls to india and calling about positions in Texas regardless of my stated Boston-only preference.

</comment></comment></comment><comment><USER6> I'm in the recruitment process right now, the signal-to-noise ratio with recruiters is so low that I've basically stopped paying attention unless they are an internal recruiter.

Is it just me, or is it far more productive to simply make it known to your network that you're looking, and let companies come to you? That's what I'm doing this time and it seems to be working quite well.

For one thing, my friends won't refer me to bullshit positions, and more often than not I'd already know someone working there, or formerly worked there, who can give me some inside scoop about the work environment and any gotchas.

I honestly can't imagine trying to find my way through the meat market that is Dice and Monster.

<comment><USER7> I'm currently unemployed.

I would say that some recruiters are great, just like some internal recruiters are poor. The worst experience I've had this round of interviewing has been with an internal recruiter, where there was both no personality fit between me and the managers/recruiters and the job was not what they had advertised.

I alerted my network that I was looking for work before I resigned. I didn't get an attractive offer through my network so I have to look through ads on various job boards.

By replying to those ads with applications I eventually got interviews or recruiters calling me back about positions that they had not advertised yet.

You are correct in that your friends won't recommend you to a place where they aren't enjoying working or where they don't think you'll enjoy working.

</comment></comment><comment><USER8> I'm curious as to how much overlap there is in those Emails and Voicemails. My experience is that 10-15 Recruiters will all be recruiting for the same position and they monitor for new resumes and blast them with automated emails the minute you post your profile.

</comment><comment><USER9> > Additionally, and importantly, I had indicated that I would be willing to > relocate.

IME recruiters pay absolutely no attention to this field.

<comment><USER10> That agrees with my experience as well. The don't know or seem to care where I live. I had a company arrange a call with me and at the end of the call finally ask me if I was willing to relocate. I had to (silently) shake my head at that, because my address was right there on my resume. I lived half a mile from their office.

</comment></comment><comment><USER11> "Seeking freelance or short term contract iPhone and Android development positions."

That's a dream guy for so many emails I get daily and I'm not even looking for work. From my perspective it looks like everyone wants to hire someone for a 6 month contract in a city nearby (which in Texas seems to mean 3 hours is nearby) for a company whose name they won't disclose. If he said he wanted full time employment and relocation reimbursement I think the number would have been much smaller.

Edit: looks like I didn't read closely enough and I ended up venting rather than seeing that this was a research and discovery project and not an after thought while looking for a job

<comment><AUTHOR> The objective meant little: majority of the positions were for contract to hire and full-time.

</comment></comment><comment><USER12> My biggest problem with recruiters comes to my SharePoint skills. I get a ton of calls, but they don't seem to understand, "No, I don't want a SharePoint job. I dislike it intensely."

<comment><USER13> Ugh. I worked at Stellent (now part of Oracle) after they acquired a company I worked for. I don't have their product Universal Content Manager on my resume, but I constantly get emails about UCM administrator positions in BFE.

I've de-emphasized Stellent on my resume but sometimes I think about deleting it entirely.

</comment></comment><comment><USER13> I posted some numbers last week from the viewpoint of a passive candidate (my resume is on the internet and in innumerable recruiting company databases, but I do not have a Monster, Dice, etc profile):

[http://www.recursion.org/2011/5/21/recruiting-inquiries- per-...](http://www.recursion.org/2011/5/21/recruiting-inquiries-per-quarter)

For me, I got more enquiries in 2010 than 2011 so far, but I didn't keep track of LinkedIn requests, which could skew the numbers.

Most enquiries are very keyword spray-and-pray spam but I occasionally get a "smart" recruiter who will look me up on GitHub or Stack Overflow. The best one was a startup co-founder who evidentially spent considerable time reading up on me, and referenced something from a talk I gave.

</comment><comment><USER14> I've had much better luck with the 'Hiring Freelancers?' threads here than with any job board or recruiter service. For one thing it seems like people actually read posts rather than just looking for keywords.

</comment><comment><USER15> "My profile on StackOverflow careers was viewed by employers a whopping 1 time and had 3 search hits."

I've had similar experience with StackOverflow Careers. Even though my skills listed and location are in the top 5 for each, I have 31 views of my profile and 6 inquiries. And I've been on the site for over 6 months.

I get the feeling that while SO Careers has the right idea it's really a matter of where the recruiters are.

<comment><USER16> My company advertises on Stack Overflow and have had very interesting results. We get very low volume, something on the order of 1 to 3 responses per posting. However, the quality of these applicants is very high, which is great because we are not looking for commodity programmers.

I think SO Careers is currently a sort of high-end site for programming jobs, and Monster is a meat market.

<comment><USER17> As someone who also has his CV up on SO Careers, this is interesting to see that it is designed like that. I was also concerned about the very low number of views and times appearing in search results.

</comment></comment></comment><comment><USER18> Can anyone here share some ideas about how all that recruiting activity can be automated?

It is already partially automated (keywords search), but that's obviously not enough.

Better matching algorithms are needed, so neither job seekers nor recruiters would be overloaded with poor matches.

Anyone?

<comment><USER19> Hi,

Dan Arkind from JobScore here. We have spent some time on this. Check out our stuff at www.jobscore.com or holler if you have more specific questions - firstname.lastname@example.com

The crux of what we do is a parse and clean pattern with a relatively straightforward resume fit scoring (or matching if you prefer, tomato, tomatoe).

You can enter weighted keyword terms (useful), but we also FILTER based on location, experience level (employers, job titles) and education level (schools, degrees). We've found this does a decent job of "wheat from the chaff" separation when you receive a lot of job applications.

The reality when you are hiring is that you definitely want to _actually read_ and review ~ top 25% of inbound applications.

Finding matches in larger data sets (100M+ LinkedIn profiles) is obviously harder... but filtering one level down in structured data (degrees in education, job titles in employment) makes matches relatively precise.

There's a non-trivial challenge in normalizing job title information (javascript ninja vs. front end software engineer vs. awesome developer!) and degrees that could make matching more precise, but we aren't aware of anyone who has really taken this on (bueler?)

Variables that aren't typically captured (like salary) are really strong indicators of a match as well...

LinkedIn's (interesting) secret sauce here is relationship metadata (who you know) as a filter. LinkedIn also captures reputation metadata and the folks over at www.honestly.com are doubling down on this. We have an (undisclosed) secret sauce angle to matching at scale... but we'll need a heck of a lot more data for that to really matter...

In general though, you don't want or need an exact match (who you are going to hire), you just want what's close (who should I call).

Give jobscore a whirl & see if you have any additional input!

</comment></comment><comment><USER20> I'm going through a similar experience. I haven't posted my resume anywhere and I'm not even really 'looking' right now. But I've got a ton of emails from people who've seen my tweet on leaving MSFT or better, from a post on HN about it.

</comment><comment><USER21> Off topic but I love the link design used on his site.

</comment><comment><USER22> I would love to know how many job postings and recruiter calls there are per actual job. I seem to see a number of suspiciously similar job descriptions anytime I look.

I've had to completely obliterate sections of my resume because keyword- searching recruiters would glom onto them like flies on a turd.

Oh, and one tip: never, _ever_ go to a recruiters office because they "might have some positions for you". I relented and did this _once_. It's a phenomenal waste of time where they try to pump you for information and contacts.</comment>


Immersive Linear Algebra – A free interactive online book - <AUTHOR> http://immersivemath.com/ila/index.html <comment><USER2> This looks awesome. The popup-help's are a little jarring though since there's no indication as to which words will trigger a popup. Also:

"Oh come on, you should know what a vector, v, is by now. Check out Chapter 2, for crying out loud."

seems kind of harsh to say to the reader while they're reading the first sentence of Chapter 2..

<comment><USER3> "Kind of harsh" is an understatement. Insulting the reader like this is not acceptable. Mathematics is already difficult enough to learn by its very nature. Authors, you don't need to help make it more difficult. We already have a hard enough time convincing people that they _can_ learn something this difficult.

<comment><USER4> Thanks for the feedback. We have removed the popup for "vector".

</comment></comment></comment><comment><USER5> I always see linear algebra on HN and many people comment on how they never understood the subject. This makes me ask: what exactly is it that people don't get about linear algebra? What makes it appear to be a difficult subject?

As someone who has used linear algebra almost every day in some form over the last decade, it's hard to get a perspective of what aspects are challenging to the beginner. And since I TA courses that involve linear algebra, it is good to know where the problems are.

<comment><USER6> I see that chapter 10, on eigenvalues/eigenvectors, is "Coming soon!".

Eigenvectors never made intuitive sense to me. As with the various decompositions (Cholesky, LU, etc), I could apply the math as algorithms to follow, but never got to the point where felt I could apply them to new problems.

Then again, in practice, I've only needed eigenvectors once since college, and it was more a rote implementation described in a paper. (In other words, don't feel like you should educate me on them here.)

Since you are a TA, don't you get some idea of where your students struggle with linear algebra?

<comment><USER5> Interesting. I used linear algebra with quantum mechanics where eigenvectors represent quantum state of the Hamiltonian which is how I initially understood them.

And as for TAing, have you ever TA'd? You definitely get a feeling but I can count numerous times when I've stood in front of the tutorial class and asked if there are any questions only to get no response back. I think it's a symptom of first years. I've TA'd calculus as well and I get similar responses. It's very frustrating sometimes.

<comment><USER6> I have TA'ed. Asking for questions in public doesn't help much. Students rarely like to admit they don't know something.

I was thinking more of when you look at their assignments. There are often multiple ways to approach a problem, and the route chosen can reveal something about one's level of comfort.

It doesn't help that university TAs get almost no training in how to be a TA. At least, I didn't.

<comment><USER5> Yeah I know. It's hard to squeeze information out of them. I actively tell them to please, please come to me if they don't understand something and I have office hours for a reason. Yet no one takes advantage. At a certain point, you can only do so much since I'm a grad student and not a lecturer and my time is finite.

The problem I've found with assignments though is that people copy and cheat. Many times someone will do very well on assignments and then do absolutely terrible on midterms and finals. It's very frustrating. I remember one course where everyone did nearly perfect on the assignments and yet the final and midterm followed the standard bell curve.

<comment><USER3> It's worth devoting a portion of classroom time (in my opinion, a substantial portion) to discussion of the topic, perhaps focusing on particular problems and generalizing from there. For example, you might select random students each day to present problems from homework. If you've ever noticed that you learn something better once you teach it to someone else -- well, it works for your students, too.

Moreover, if you create a non-judgmental environment in which people are free to talk about their approaches to problems and get feedback not only from you but from other students as well, then just by watching carefully, you will learn some of the more common gaps in understanding. (Note that some students will not talk in these situations unless forced, but that does not mean they do not benefit from following the discussion.)

If you're anything like I was when I was first TAing courses like this, you might think that if you do this, you won't have enough time to "cover the material". But I put it to you that a lecture that is not absorbed doesn't cover anything.

</comment></comment></comment></comment></comment></comment><comment><USER7> I never studied math in college, in fact I barely studied math in high school. It was always daunting to try to parse the notation and figure out how the abstract symbols corresponded to some piece of reality.

When I became a self-taught developer I found my math skills continuously lacking. I started teaching myself on Khan Academy and really picking it up a lot better because of the simplicity of the language and the good examples. I finally realized I learned math best visually.

Interactive lessons like these are great. There are things that can be improved about this book (load times and enhanced interactivity) but all in all this a great resource for people that learn best visually. I'll come back to this soon in my future self-education.

<comment><USER8> What exactly do you do when you need math skills in developing? What do you develop with it? Some specific examples?

I've done math while developing 3D stuff, physics simulation and a lot of things - yet I never felt like my math skill mattered that much. And I really dislike theoretical math like in school.

<comment><USER9> Math is certainly not for everyone, but I actually found that once I started diving into pure math (NOT what was taught in my school's math curriculum) it was a whole new world.

Did your school actually teach pure math?

I bet a lot of programmer types had similar frustrations to the computationally intensive version of math taught in many high schools when they knew that these processes could simply be automated.

<comment><USER8> I don't even know what pure math is to be honest. The courses I specifically lost interest in was linear algebra, discrete mathematic and statistic- something. I did however use linear algebra just after while writing a simple collision/physics engine prototype and found that to be very fun.

</comment></comment></comment></comment><comment><USER10> I'm sure that this a wonderful book, but please note the error right off the bat in equation 1.3 The tangent of the angle in question is b/a NOT a/b as stated. Probably a good idea to keep an sharp eye on the math as you go along in this thing.

<comment><USER4> Send me your name to firstname.lastname@example.com and we will add you to the acknowledgements section!

<comment><USER10> That's o.k. I'm usually the one making boo-boos like that. Glad we caught it.

</comment></comment></comment><comment><USER11> This is actually pretty cool! I spent the last few weeks going through Gibert Strang's popular OCW course[0] & I'm sure this would serve as a great companion. I can't wait for the chapter on Eigenvalues to be published as that is something I don't yet grasp intuitively. Great work and thanks for making this free and accessible!

[0] [http://ocw.mit.edu/courses/mathematics/18-06-linear- algebra-...](http://ocw.mit.edu/courses/mathematics/18-06-linear-algebra- spring-2010/video-lectures/)

<comment><USER12> shoutout to LAFF as well

\- [https://www.edx.org/course/linear-algebra-foundations- fronti...](https://www.edx.org/course/linear-algebra-foundations-frontiers- utaustinx-ut-5-03x)

\- [http://www.ulaff.net/](http://www.ulaff.net/)

might be good for you if you're motivated by a deadline, graded progress, some Matlab/Octave implementation, and certificate of accomplishment, vs. self- paced Strang (AFAIK).

<comment><USER11> Had no clue about this course! Thanks a lot for the recommendation!

</comment></comment></comment><comment><USER13> Similar project, but for multi-variable calculus:

[http://mathinsight.org/thread/multivar](http://mathinsight.org/thread/multivar)

</comment><comment><USER14> Is this available in an off-line bundle? I am becoming increasing wary of online books/training/applications that can not be read locally. If I am going to take the time to read through a full book (possibly weeks of reading) I want to be able to use/reference it in 5 years like my paper books.

most of the value of a good math book is that years after reading it you can use it as a reference to look things up you will inevitably forget.

<comment><USER15> While I don't disagree with your comment, I think once you've learned this material you could reasonably look it up in a different book. Put another way, going through this course might greatly increase the value (to you personally) of having any other linear algebra text available. It's not necessary to look things up in the same textbook you learned them from.

<comment><USER14> This issue has come up with MOOCS also. If you look at the MOOC sites they offer there class content including videos as downloads. Even tho most of the MOOCS are introductory courses and you probably would need to get a good book to go along with them lots of people were requesting downloads of the content. There is a variety of reasons why people want off-line bundles. Its just something I have gotten use to with this sort of content.

</comment></comment></comment><comment><USER16> In terms of programming and linear algebra - please consult someone who is actually knowledgeable about the subject if you're implementing it in code.

Linear algebra without error analysis is very dangerous. Many many things are theoretically useful, but can't be used in practice. You can't calculate determinants, you can't count unique eigen values, you can't use certain decompositions.

Unfortunately this isn't really topic you can do a quick tutorial on and start writing new algorithms

<comment><USER17> and also don't compute the inverse if you don't have to!

</comment></comment><comment><USER18> Slow to load (possibly due to HN traffic), but once it does, it seems like it's got the makings of a great learning tool. Waiting for matrix chapter since that's where I stopped learning Linear algebra on both my past two attempts (Gilbert Strang made my mind explode as I tried to comprehend past 4 dimensions. And then I just got lazy). Really want to pick this up because without linear algebra it's easy to get lost in all the major streams of Machine Learning. At least that's what I felt when I tried to skip linear algebra and move on to ML.

Sigh. I sometimes wish I paid more attention to my studies while I was in school instead of goofing off and playing card games :'(

</comment><comment><USER19> At some point, I'm hoping to get enough of this to solve this problem: you've taken a picture of, say, the Mona Lisa in its rectangular frame, but because of crowds you weren't in line with dead center, instead you were 5 meters back, 1 meter high, and 2 meters to the side, and not even pointed at the center. Your photo now contains some quadrangle that is a _projection_ of the rectangle. I'd like to tag the four corners and have an algorithm map the photo to its original rectangle - I intuit there's enough information in the photo and the four tagged points, given that the original is actually a rectangle.

<comment><USER20> A word of warning about solutions to this problem. The "easy" version states it this way: the mapping you want takes (x,y) to ((ax+by+c)/(gx+hy+i),(dx+ey+f)/(gx+hy+i)) for some a,b,c,d,e,f,g,h,i -- a general "projective transformation". If you decide ahead of time exactly what rectangle you want to map to, you have 8 constraints on a..i (two coordinates for each of four corners) and one irrelevant degree of freedom (if you multiply all of a..i by the same constant, nothing changes) so you have "exactly enough" information to find those parameters. So you solve the equations and you're done.

This works, provided your measured positions are perfectly accurate, but it isn't the best you can do. The reason is that a single projection actually has one degree of freedom less than a general projective transformation. (Three parameters to say where your camera is located. Three to say how it's rotated. One scaling factor. Total is 7 rather than 8.) This means that there's an extra (slightly hairy) constraint on the parameters a..i, which turns out to mean that the aspect ratio of the rectangle you're mapping to is determined for you.

Imposing that constraint will give you (1) more information -- you won't have to know ahead of time what aspect ratio you have -- and (2) a more accurately estimated transformation.

You can find more details of this stuff in, e.g., this PDF document: [http://people.csail.mit.edu/bkph/articles/Harmful.pdf](http://people.csail.mit.edu/bkph/articles/Harmful.pdf) .

</comment></comment><comment><USER21> I was thinking of working in a lab that does research in the field of computational biology. However, I never took a linear algebra course before so I always felt like it would be a waste to make an attempt. I did a quick skim and this looks very promising. If I can comprehend this, then maybe I will be of some use in the lab. Thanks for sharing :)

</comment><comment><USER22> This looks amazing and well timed as I've been attempting to learn Linear Algebra on the side. However, everything after Vector Products is "coming soon". I will definitely use this once it's all there, which i hope is soon. Heck I'd be willing to pay for it if it were ready now.

</comment><comment><USER23> Is this available in an off-line bundle?

<comment><USER4> At this time, it is not available as an off-line bundle.

</comment></comment><comment><USER24> Really great site. It's clean, look forward to seeing the complete interactive book.

</comment><comment><USER25> Does anyone know if there's source code or a github page associated with this? It would be nice to submit fixes to errors, typos and maybe make suggestions.

For starters, there might be a way to do away with the loading screen for shorter pages.

<comment><USER4> At this moment there is no github available, but bugs reports are welcome at email@example.com!

</comment></comment><comment><USER26> This is the first time I've ever heard someone say algebra with a hard g sound.

[https://www.youtube.com/watch?v=TIcSnsmitHw](https://www.youtube.com/watch?v=TIcSnsmitHw)

</comment><comment><USER27> Thanks for this! I am currently taking linear algebra with Serge Lang's book and I feel that this is a good addition to my studies. When do you expect to have the other chapters done?

</comment><comment><USER28> Cool, well doesn't work on my mobile device, but I'll definitely check this again later since I need to review more Maths before going back to uni

</comment><comment><USER29> Not Free? That's fine, but I couldn't see a statement of that. If so, I wonder how they plan to do DRM.

<comment><USER4> This service is free of charge!

<comment><USER29> Are you involved with the project?

If so, thank you. What is the license?

</comment></comment></comment><comment><USER30> Are there any ways to contribute?

</comment><comment><USER31> To bad that teachers rarely have the freedom to teach using tools of their choosing

</comment><comment><USER32> From a technical aspect, this is an excellent implementation of MathJax.

</comment><comment><USER33> 70 seconds to load a chapter? That's a terrible benchmark for even for some of the heaviest websites out there!

This may not be a popular opinion but I (and many ordinary readers like me) see that link as a website. Not a book.

It feels heavy and overwhelming to see a large number of 3D diagrams and visual depictions on just one web-page. Having to scroll down to read the full chapter with all that animation and "motion" is probably a bad move too. Given that this is supposed to come off like a book you can probably ditch the scroll.

Ideally, you'd want to give away few concepts in small easy-to-understand chunks with just 1 or 2 figures per page. And let the reader flip/click over to the next section like it happens with an ibook or kindle book or even a real physical book.

IMHO the idea of ripping apart a book at its spine and forcing the loose design of websites over it is a complete no-go for avid book readers. Especially for the mobile and tablet users (probably even for the desktop users!, why else would everyone insist to download PDF, ePub or other artifacts?). But I'm sure that a section of developers over here wouldn't agree with my opinion. So take it all with a pinch of salt.

Also just the place where I'd let the designers take over.

<comment><USER34> > _70 seconds to load a chapter?_

The full note says "up to 70 seconds on tables." On my computer it took less than 2 seconds.

<comment><USER33> It took over a minute on mine; but I'm sure they're hammered right now.</comment></comment></comment>


Test functions for optimization - <AUTHOR> https://en.wikipedia.org/wiki/Test_functions_for_optimization

<comment><USER2> It would be nice to know why each of the test functions are interesting or challenging for optimization algorithms.</comment>


Rootless Containers - <AUTHOR> https://unit42.paloaltonetworks.com/rootless-containers-the-next-trend-in-container-security/ <comment><USER2> > Slirp is a well-known project that was originally and mainly used for > networking in QEMU (aka Quick Emulator).

Good grief, that's off by almost 15 years. Slirp was _originally_ a SLIP endpoint you could run on a remote dial-in shell account to connect your local system to the internet. As it happens that's basically the same problem needed to get (something like) IP to work out of a userspace context in general, so it got appropriated by the container community and used pervasively. But it's roots go much deeper.

Also... "Quick Emulator"?!

<comment><USER3> SLiRP was written by Danny Gasparovski from Canberra.

Actual SLIP needed privs on the host to configure everything. slirp did it in usermode, allowing lowly undergrads to get real IP connections at home from the terminal services universities provided. Then you could run NSCA Mosaic at home :-) And ftp things directly, instead of downloading to your shell account tmp dir and using zmodem to transfer it the last hop.

[https://www.linuxjournal.com/article/1174](https://www.linuxjournal.com/article/1174)

It went away as real ISPs began to appear, offering PPP connections, and universities dropped their dial-in services. Strange and glorious to see it back again.

<comment><USER2> It's that exactly what I said?

<comment><USER3> Just expanding. I was already writing it when your post appeared.

</comment></comment></comment></comment><comment><USER4> I've been following podman for rootless containers. It works fairly well on Fedora. RHEL 8 works, but has older version of packages compared to Fedora.

There are some fairly well documented shortcomings to consider/work-around. You can find that list at [https://github.com/containers/libpod/blob/master/rootless.md](https://github.com/containers/libpod/blob/master/rootless.md)

<comment><USER5> The big annoying one in HPC is NFS/GPFS, but that will actually work just fine if you stay as root inside the container, which maps to your uid outside the container.

<comment><USER6> I'm a little confused by this statement, since at my current employer and previous employer we used NFS mounted home dirs and I would and currently do need to explicitly change my ~/.config/containers/storage.conf to point to a local mount point, such as /var/tmp/containers/$USER in order to perform anything rootless container related. In my case that's with Podman on RHEL 7 and RHEL 8.

<comment><USER4> That's an acceptable workaround. Just remember the containers aren't available on NFS and thus other systems.

<comment><USER6> I'm aware, I'm trying to determine what prpl meant by

> but that will actually work just fine if you stay as root inside the > container, which maps to your uid outside the container

<comment><USER4> I'll let Dan Walsh explain it [https://www.redhat.com/sysadmin/rootless- podman-nfs](https://www.redhat.com/sysadmin/rootless-podman-nfs)

In short, you don't remap when running as root in the container, thus no uid/gid remapping.

<comment><USER6> I had a derp-out moment yesterday, I totally misinterpreted "as root in the container". The topic was about rootless containers, so I was completely mentally blacklisting the idea of starting a container from the root user account.

</comment></comment></comment></comment></comment></comment></comment><comment><USER3> Singularity containers go some way towards running without root, though it defaults to setuid setup at boot and dropping privs before execution.

Singularity makes some bad design choices though, like eliminating layers, which results in proliferation of huge container images cluttering everywhere, with no idea what they do. It's really designed for HPC administrators who don't like end users.

[https://sylabs.io/guides/3.5/user- guide/security.html](https://sylabs.io/guides/3.5/user-guide/security.html)

<comment><USER5> They also have a bad record regarding security, and usability without the setuid scripts is poor.

<comment><USER3> Well I only see the one bad CVE, but yes security through extra setuid C code seems a bad idea. [https://www.openwall.com/lists/oss- security/2019/05/16/1](https://www.openwall.com/lists/oss- security/2019/05/16/1)

Ironically, I keep getting told I have to switch over from docker because of security. Plenty of IT security folk have their knickers in a twist at the idea of non-sysadmin priviledged users. They would rather run a giant insecure system (Linux or Windows AD) with lots of LPE and lateral movement than smaller more isolated systems with more trusted users and less LPE. Dev(Sec)Ops concepts still haven't penetrated very deep.

<comment><USER5> Several DOE sites won't even consider Singularity, including NERSC, who created Shifter (aka Docker + patching - networking) around the same time as development at Singularity started at LBNL (NERSC's parent lab). LANL created CharlieCloud ([https://hpc.github.io/charliecloud/](https://hpc.github.io/charliecloud/)) because they needed a hard focus on security first.

There is quite a bit of distrust of Singularity places that value security. I'm hoping podman rootless can eventually come through and render all the bespoke implementations moot, but it will probably be a few years.

</comment></comment></comment></comment><comment><USER7> > The downside is that V2 doesn't support all the controllers that were > implemented for cgroups V1 (e.g. devices, net_cls, net_prio,etc.).

device controller is present since kernel 4.15.

> Adoption status

Docker/Moby supports FUSE-OverlayFS and cgroup2 as well on master. Planned to be released as v20.0X.

> spearheaded by Podman and LXC.

Yes w.r.t. cgroup, but the network stuffs (slirp4netns & RootlessKit) were originally written for Docker/Moby :)

> the truth is that container engines run Slirp without the seccomp support

Untrue. [https://github.com/containers/libpod/blob/d4a3c05c0fcd0c53fa...](https://github.com/containers/libpod/blob/d4a3c05c0fcd0c53fafda09a682435212b68a68f/libpod/networking_linux.go#L228) [https://github.com/moby/moby/blob/b47e74255811b2ead92b222541...](https://github.com/moby/moby/blob/b47e74255811b2ead92b22254174c27ae9d6c9f4/contrib/dockerd- rootless.sh#L82)

</comment><comment><USER8> We are using Prisma Cloud at work. I'm always surprised to see such a half user friendly tool.

I thought, when i used that tool for the first time, that is some small company building it but nope its paloaltonetworks.

<comment><USER9> Prisma cloud Was twistlock before it was bought by Paloalto, a small 120 people company.

<comment><USER10> Actually only the Prisma Cloud Compute part is Twistlock

</comment></comment></comment><comment><USER11> [https://github.com/nanovms](https://github.com/nanovms) is another unikernel attempt to solve the security problem, is an actual VM runnable on type1 hypervisor.

In contrast, gvisor, needs ptrace or kvm.

Both nanovms and gvisor aim to provide an abstraction through emulated system calls.

</comment><comment><USER12> How does it relate, security wise, to mirageos? I know it's apples and oranges, but only on security dimention scale, is one far better than the other or hard to say?</comment>


Homemade Analytics with Ecto and Elixir - <AUTHOR> https://dashbit.co/blog/homemade-analytics-with-ecto-and-elixir <comment><USER2> Great strategy, I love how elegant it is, but I do wonder about two things regarding this method:

Testing it (especially with async integration/e2e tests, which I prefer) would be tricky, I'd want some tests to verify that the "GenServer write cache" is more or less counting correctly under some (potentially stressful) scenarios that I can stress out by having other things run in the VM.

From what's presented, I'm not sure yet how to get this to work with distribution, in the case that you would want to drop this into a distributed phoenix setting. Do you start the pages :global instead of registered? Do you start a Registry with :global, and have the cluster restart it if vm that hosts it dies?

<comment><USER3> Distribution is not necessary. Each server/node will have its own set of processes doing upserts, which are atomic.

The testing story from Elixir is relatively straight-forward too. I send a bunch of requests and then ask the supervisor to shutdown, which forces all processes to terminate and perform their pending writes.

<comment><USER2> > Each server/node will have its own set of processes doing upserts, which are > atomic.

Perfect! thank you for clarifying. Or maybe i should have read it more carefully.

> The testing story

I keep forgetting ExUnit's start_supervised! exists.

</comment></comment></comment><comment><USER4> Very interesting! Thanks so much for sharing. I have a couple questions:

1) The `bump` function interacts with the worker GenServers via `send(pid, :bump)` and the GenServer has a `handle_info` for that. I would normally add a client function to the worker module which uses a `GenServer.call(...)` instead. Was that just to make the blog post a bit shorter, or are there tradeoffs I'm missing?

2) In the case of millions of pages, the post suggests terminating the processes. What about `hibernate`? Could that be an intermediate approach to reach for, for some relatively large number of pages?

<comment><USER3> 1) I wanted it to be async as there is not much reason to wait for the process since the database writes are async too. So either send/2 or cast/2 would be fine.

2) Good call on hibernate. It could definitely be an option to consider on all implementations.

</comment></comment><comment><USER5> Could you perhaps have one process for all paths that just contains a map with the counts and receives messages to increment? And then that map gets periodically persisted to the db as a bulk update? Is a separate process per path needed?

<comment><USER2> strictly speaking it's not needed, however, you probably don't want to do that because raw erlang processes are single threaded with no shared memory (but also no transactional locking, mutexes, or channels to worry about!) so at a certain scale you will become bottlenecked on that one process. ETS tables (an internal k-v lookup system) cheats a bit on the "no shared memory" rule, and Registry is backed by that and able to be a high-performance solution for sharding your path to the process that needs to handle.

</comment></comment><comment><USER6> Very educating! I was surprised that there was the possibility of a race condition where it starts two processes for one path.

</comment><comment><USER7> That's a great educational read on Dynamic Supervisors and Registry.</comment>


Exa – a modern replacement for ls - <AUTHOR> https://the.exa.website/ <comment><USER2> Here are the advantages of _ls_

1\. It's already on my system. No installation necessary.

2\. It's on EVERYBODY's system. No matter what Unix-based terminal I go up to, I know it has _ls_.

3\. I know how _ls_ works. I can focus my time on solving business problems rather than learning a variation of a tool I've been using for 30 years.

<comment><USER3> ls is also defined by POSIX, including the format of output so you can reliably parse out metadata. IIRC there's no other well-defined way to query, e.g., the size of a file. The stat(1) command is non-portable, not always available, and the GNU and BSD versions don't even pretend to behave similarly in terms of the option flags or format specifiers.

I'd have more interest in these new utilities if they actually paid some attention to these sorts of details. It would be trivial to both implement POSIX semantics as well as provide all the fancy behaviors you'd want as an extension, especially because POSIX behavior is often only defined for specific situations (i.e. if a particular flag is specified and printing to a pipe or from a non-interactive session).

But when utilities don't bother implementing basic POSIX behavior it tells me that they don't actually understand all the _reasons_ for particular behaviors. You can't fix something if you don't understand what the problems are. Simply declaring something as legacy and non-sensical doesn't cut it.</comment></comment>


YC batch s2012, not - <AUTHOR>

Some of you received good news today from YC, some haven't. I'm in the batch that will serve to highlight deficiences in the screening process, by making it without YC' s involvement. For others in similar situation, let me cheer you up by reminding that the most important validation of your idea comes from users and traction. Application screening is tough intelligence test for screener, and they do make mistakes right and left. As Om Malik puts it: "I am old fashioned re startup contests. Good companies can manage w/o them. Angry Birds did not need them". As well as Google, Facebook, Instagram, and thousands other great businesses. Now, have a drink and get back to building whatever empire you were building. Good luck! <comment><USER2> 1 point by EREFUNDO 20 minutes ago | link | edit | delete

We are PayGuard and we're building a payments platform that would specialize in long-distance/cross-border transactions. <http://stark- river-6968.herokuapp.com/> We do this by combining your normal payments gateway with the global network of an international money transfer company (Western Union) with the twist of "escrow". We got our rejection letter too but we are forging ahead with launching our beta late this May. We believe eCommerce will globalize and payments will be at the forefront to make this happen. We want to create a world where anyone can buy or sell anything anywhere. We would appreciate any candid feedback on our idea....intellectual honesty is the best weapon against self delusion.

<comment><USER3> I would be interested in talking to you. Can you contact me (plg at stanfordalumni dot org)

<comment><USER2> Sure np. I just sent you an email. :-)</comment></comment></comment>


EveryDNS/EditDNS Nameservers shutting down on Sep 9, 2011 - <AUTHOR> http://dyn.com/everyeditdns-discontinued/ <comment><USER2> dyn.com has come a long way from the hobby project dyndns.org once was. I haven't been there for ages.

Interesting: Once they began adding the paid accounts, the gave away free non- expiring accounts for people who have donated while the service was still free and to this day, my pro account is flagged with "Expires: never". It's cool that they continue to honor this even years after shedding the hobby-project grove.

</comment><comment><USER3> I moved all my records out to namecheap considering i have a few names with them as well. Namecheap is full featured an d includes txt records. Free as well.

<comment><USER4> Could someone explain why goombastic is being down voted? I am unable to figure out what is objectionable about his comment, unless the provider he mentioned is known to be bad.

<comment><USER5> Aren't up and down votes invisible?

<comment><USER4> If a comment is net negative, it is shown in a hard to read color, the more harder to read the more negative it is. I don't know how many different levels there are, but here are the colors I've seen:

       #e6e6e6
       #9c9c9c
       #737373
       #bebebe
       #aeaeae
       #888888
       #cecece
       #dddddd
       #5a5a5a

At the time I asked why he was getting down voted, it was at least a net of two down votes, because I up voted and that did not restore the comment to the normal color.

</comment></comment></comment></comment><comment><USER6> Considering dyn.com started interrupting Everydns' users services two days earlier than they said they wound (in their own instructions), I have moved to alternative DNS providers, and I really hope many other users did too.

</comment><comment><USER7> Personally I've moved to GratisDNS a long time ago. I've never had any issues with them and they are always happy to help. It helps to be able to read Danish though.</comment>


NYC Planners Propose Subway Line Just for the Boroughs - <AUTHOR> https://nextcity.org/daily/entry/nyc-borough-subway-toronto-expansion-jakarta-light-rail <comment><USER2> "Hey, I know I'm just in Queens and Brooklyn but can I get some love too?" \- G Train</comment>


Help a Startup Out  - <AUTHOR> http://eepurl.com/uIsL

<comment><USER2> This link goes to [http://us1.campaign- archive.com/?u=92be899ef5a892c60b4a6cd97...](http://us1.campaign- archive.com/?u=92be899ef5a892c60b4a6cd97&id=530cdd1f6b) which is ... an email campaign?

Were you trying to bring attention to the site mentioned in the email or the email campaign itself? Ref: <http://helpastartupout.com/></comment>


Eye Contact in Video Conferencing (2018) - <AUTHOR> https://itotd.com/articles/5279/eye-to-eye-video/ <comment><USER2> Latency is the issue for me more so than eye contact.

On video chat sometimes I'll say something like "mmhmm" or "yes" in agreement, and accidentally throw the speaking party off because my comment was delivered after a normal pause in speech due to latency.

This interruption of normal conversation flow is more problematic to me than eye contact. We both know were speaking into machines after all.

<comment><USER3> For some reason video calls have just never worked well for me. Every single time it's either latency, massive amounts of echo making it hard to speak, and "can you hear me" every minute or two. For some reason, it's 2019 and we as a human race still haven't figured out how to get a stable 480p video stream over gigabits of bandwidth.

<comment><USER4> Video conferencing worked perfectly when it was still done over circuit- switched digital telco networks. It's only the Internet that has botched things up.

<comment><USER5> If by "botched things up" you mean "Made affordable." Nobody other than Vint Cerf will argue that circuit-switched networks are not superior from a QoS point of view, but they can be orders of magnitude more expensive to build and maintain.

<comment><USER6> They should be feasible to implement within a building, between buildings on the same street, and probably between geographically diverse sites of multi billion dollar companies that spend 30%+ of their labor hours on site-spanning meetings.

</comment></comment></comment></comment></comment><comment><USER7> This will definitely never happen with "monitor"-style technology, because AR/VR with face tracking will do it. That's probably five years out.

As a side note, I believe eye contact and 3D projected body language tracking are the limiting technology for virtual offices to leapfrog physical offices.

It's my expectation that when those two technologies are cheap ($600 all-in- one device) it will massively disrupt both commercial real estate and any residential markets that are commute dominated.

I believe particularly in the Bay Area this will be the source of the next housing market collapse. Particularly since Facebook is heavily invested in telepresence now, and has a clear path to a device like I described within ~5 years.

Google and Apple, in all likelihood, will put out a similar device in that timeframe as well.

<comment><USER8> Do you have any links where we explore such prototypes?

<comment><USER7> You can look up some of the foveated rendering prototypes. The non-static ones have eye tracking.

I have seen a few headsets with downward facing cameras but not many. There are hard problems around both technologies so they are mostly research prototypes at this point I think, not consumer alphas.

<comment><USER7> Also I think some Leap Motion prototypes might be facing downward and tracking body. I seem to remember one that had the Leap sensor on little arms sticking out on little arms.

As I said I believe Facebook, Google, and Apple all have this tech on the far side of their roadmaps. So I don't see all three failing.

But even if they do, the Leap Motion roadmap points there, and... while Leap is obviously mismanaged, new parent company is UltraHaptics. Hopefully they can get Leap into a headset....

Regardless, the Leap founder (Ed: David Holz) knows exactly what's necessary for telepresence in VR, and I don't think any amount of mismanagement will stop him from executing it EVENTUALLY.

But he'll take 10 years, and Facebook might do it in 3. Apple could roll it out next year for all we know. They've prototyped all the tech already in ARKit.

David if you're in this thread and you want to build a leap headset email me. We can just disassemble Oculus Go's and add a Leap and... well you wrote the 6DOF code already right? Solder a coprocessor on the board that can do it without any battery drain. Maybe we have to design one, IDK. Sacrifice a kitten. Hire a stats PhD and make it "stochastic". Put a neural net processor between the cameras and the computer. Who knows.

Then ship it with a Nintendo 64 emulator ONLY, that's the entire OS, no games you have to sideload them. And mark it up to $999. Fund the company on preorders.

<comment><USER7> Strip off the Go's plastic and CNC a custom enclosure, faceplate carved to the buyer's design. Use a portion of every sale to fund artists creating faceplate designs for customers to choose from.

Needs IPD adjust, off ear audio

</comment></comment></comment></comment></comment><comment><USER9> > Eye contact is extremely important for meaningful communication

Some of us, specifically blind people, have lived our lives without ever being able to make eye contact, yet we still have meaningful communication, both with each other and with sighted people. I, for one, don't ever think about my inability to make eye contact, except when a sighted person brings it up (edit: and to be clear, that only happens in a discussion like this one, not when trying to communicate with me personally).

<comment><USER10> I'm genuinely curious: Do you use video chat a lot? If you do, is that a personal preference or something of a standard workflow at your job / you agreeing to someone else's preferences? My sample size of blind people I know and feel close enough with to discuss limitations/day to day issues is tiny unfortunately, so the question of whether video chats are a thing never came up (We did watch(?) movies before though).

The reason I'm asking is that I do agree with the article, but I'd phrase it slightly different: The technology right now makes video chats ~different~ and awkward due to the lack of eye contact, IFF you're used to eye contact in face to face conversations in the first place, because video chats are supposed to allow f2f over remote distances.

<comment><USER9> Thanks for asking. No, I don't use video chat much at all. Really, I only do it occasionally with my family when I can't be there for somebody's birthday (I'm in Washington state but the rest of my family are in Kansas). And of course, I only use video for their benefit, not mine.

I currently work in an on-site office environment, and only a small number of us are blind or low-vision. When I'm initiating a real-time conversation with someone, I'll often do it by IM. We may do it face-to-face if the other person is right there, but to me that's just like an audio call with 3D positioning, perfect fidelity, and no latency. To be fair, that is indeed still better than current VoIP, but not enough so that I would insist on being in the same building as my coworkers. Indeed, with an online audio group chat, I always know when someone joins or leaves the group; that's not always the case in person.

At my previous job, by contrast, we were an all-distributed team made up almost entirely of blind or low-vision people. As you would expect, we never used video. But we did use audio a lot, both one-on-one and group chats. (Our favorite voice chat system ended up being TeamTalk [1].) I never met most of my coworkers in person, and I never felt that this was a problem. It only just now occurred to me that the few sighted people on our team might have been uncomfortable with the way the rest of us worked. As for the rest of us, as far as I know, none of us ever wanted to be together in an office building. At least not for the sake of communication; having a shared pool of test hardware would have been nice from time to time.

[1]: [http://bearware.dk/](http://bearware.dk/)

</comment></comment></comment><comment><USER11> One option is to capture the video with depth as well as colour data and then just rotate it to point in the right direction(s) to maintain eye contact. This is what we experimented with on [https://matrix.org/blog/2018/02/05/3-d-video-calling-with- ma...](https://matrix.org/blog/2018/02/05/3-d-video-calling-with-matrix- webrtc-and-webvr-at-fosdem-2018)

</comment><comment><USER12> I really don't think looking someone in the eye is as important as it sounds. Yes facial expressions communicate a vast amount of information but I can still see someone's face even if they are not looking me in the eye. Tbh I actually don't like looking people in the eye for the whole of a conversation; it would feel weird. For what it's worth, I don't feel like someone is being dishonest if they don't look me in the eye. That kind of myth can go in the bin along with the idea that a firm handshake shows confidence. That kind of thing makes me cringe.

</comment><comment><USER13> One of the simplest things would be to simply allow the user to put their thumbnail at top center, where the camera usually is. Even better, maybe position it to where dynamically to above the head of the speaker on the other end. In my case, for example, the geometry of my desk leaves the front edge of my microscope visible in teleconferences, so I am no doubt slightly left of center in all cases. In any case, I know that I for one spend a non-trivial amount of time looking at my own camera feed, seeing if the video is ok: am I dropping frames because of a visible ceiling fan? Is the sun coming through a window behind me, blowing me out?

</comment><comment><USER14> _... I think most of us would say that's a big improvement over audio-only communication._

Never assume that just because you have a particular personal preference that most people share it.

<comment><USER15> I consider a well written email to be a big improvement over audio only communication.

</comment></comment><comment><USER16> Eye contact would be brilliant but at the moment I would settle for full- duplex audio. It really impairs the ability to have a natural conversation in e.g. Google Meet when you have to wait for the other party to be totally silent before you start speaking.

</comment><comment><USER17> Link to one of the more recent and interesting projects mentioned: [http://sites.skoltech.ru/compvision/projects/gaze- correction](http://sites.skoltech.ru/compvision/projects/gaze-correction).

This would be a crazy difficult (and fun) domain to work in. Humans are very well tuned to perceiving facial details - the margin for error would have to be tiny. I'm still uncertain if images processed this way could escape the uncanny valley, but this appears to be a much more technically feasible approach for consumer use than transparent displays, multi-cam setups, or camera arrays embedded in displays.

<comment><USER18> If I were a betting man, this is where I'd put my money. It seems attainable via software or hardware assisted processing once the model has been computed. All the other solutions seem too expensive or hardware intensive to me.

</comment></comment><comment><USER19> I'm a full time remote consultant. I've noticed anecdotally that over the last year 80% of my contacts have started muting their camera all the time. Some cite "bandwidth" or other silly excuses; most just say nothing.

I'm as insecure about my appearance as anyone else- what's the deal? I keep my camera on until it's obvious that nobody else is going to show their face. Then I have to be the awkward one to turn off.

<comment><USER20> I've been doing video meetings for years, and I've seen video muting go up and down based on team expectations / social morays, general engagement, and the kind of meetings (e.g., one where lots of people are just trying to get some situational awareness, but aren't really participating).

I personally get annoyed when people video mute by default, and when I was a manager it was something I would bring up in 1:1s. Lurking on meetings is fine, but if you have a real role in the meeting and you aren't multitasking a meal or something, I feel strongly you should have your video on and be engaged, and most of the time when people are video muting it's because they are hiding their distraction and lack of attention, or else it's reached a critical mass where people are muting just to fit in.

Now that I'm an IC again generally the best I can do to encourage people to unmute is just name them: "hey Joe, are you there?" even though I know full well they are connected. It's admittedly a bit passive aggressive, but it's also a way of gently telling the person they aren't being present, and it's unlikely I'm the only person who notices.

I also mute myself for the wrong reasons, so I'm not trying to make this an indictment of individuals. But it's so easy for people to drift away from their work, especially when you are remote, and we need to look out for each other and not just accept dysfunctional behavior.

<comment><USER14> Wow I hope we never work together. A mature team trusts one another and assumes the best. If I got that feedback from a manager in a one-on-one I would put in notice that day. What a horrible attitude to bring to your work interactions.

<comment><USER21> If you had a private conversation with your manager, and they asked you to "be more present" at telemeetings via unmuting your video stream, your response would be to QUIT? Maybe before that point you should talk through the topic with your manager. Surely the best result for everyone is to have a shared understanding, rather than making what seems like a minor communication "difference of opinion" a dealbreaker.

<comment><USER22> This is butts-in-seats mentality, but for remote workers:

> _most of the time when people are video muting it 's because they are hiding > their distraction and lack of attention_

The OP _assumes_ that those who have their camera off are wasting time, because they can't see them to prove that they're not.

<comment><USER21> I get that, but... butts-in-seats as an expectation for the work day (which is typically where the policy/work culture is called out), is quite different from a butts-in-seats expectation for meetings where one has a "real role".

<comment><USER14> Can you clarify your position here? What do you see as the main issue with butts-in-literal-seats, and what about this hypothetical remote meeting is "quite different"?

<comment><USER21> GP cited "butts in seats mentality" in a way that I interpret as pejorative, referring to office cultures where physical presence during working hours is more important than output.

A meeting is specifically about communication. A participant at the meeting that is inattentive is either wasting others' time, or should probably politely step out, or at least should not have been asked to attend. Being present _is_ a priority for a good meeting, hence the pejorative "butts in seats" comment doesn't make sense to me.

<comment><USER14> The output of an interactive meeting is the interactivity, not the appearance of interactivity.

<comment><USER21> I don't disagree with this; I just think dropping the video feed can impact the interactivity of a meeting.

</comment></comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER23> Eye contact is something I constantly need to remind myself that people feel is really important, but I cannot say I'm naturally aware of its necessity.

<comment><USER24> Yea, I find it really tricky to both think about what I'm trying to say and focus on maintaining eye contact.

</comment></comment><comment><USER25> Combining Tobii eye-tracker with some software (machine learning) based correction system might be interesting project to try.

You could collect training data by setting up webcam through teleprompter, regular webcam and Tobii on a machine. Just record normal usage and then learn a model using eye-tracker data and regular webcam data as input and data captured through teleprompter as target.

With Tobii the system would also know who you are looking at on the screen. With custom conferencing software, you could deliver the software modified eye-contact stream only to that person.

[https://gaming.tobii.com/product/tobii-eye- tracker-4c/](https://gaming.tobii.com/product/tobii-eye-tracker-4c/)

</comment><comment><USER26> Does anyone wish we'd just attempt to have fewer video conferences instead of trying to tweak this terrible technology?

</comment><comment><USER27> I am really amazed that each video call app doesn't have an option that adjusts look of the eyes of the person you are talking to so they seem to be directed at you.

There's no magic in how people look when they look at you. All the magic of feeling when someone is looking at you happens in the recipient's brain.

<comment><USER28> eyes are the w̶i̶n̶d̶o̶w̶s̶ linux to the soul

</comment></comment><comment><USER29> This will be solved when in-display cameras become ubiquitous. Probably the entire display will be the camera, without a lens obviously. Using some nifty algorithms you can construct a focused image from that. It'll just be a layer inside the display.</comment>