Ask YC: How many hours do you sleep on average ?  - <AUTHOR> Since years I tried to wake up earlier and reduce my sleep time. But it is a daily struggle for me. By reducing sleeping hours I hope to be able to do more everyday. I know that some people need only 4h sleep and they are full of energy. I wish I could do so but I usually need 8.5 hours. I would like to  know how many hours you guys sleep and if you have some tips to reduce sleep time. Do you think we are "born" with a needed amount of sleep or can we change it? I am also interested to know at what time do you wake up every morning. <comment><USER3> It doesn't work. You can't change the amount of sleep you need by any significant amount. If you consistently shortchange yourself by a small amount each night, you may be able to _convince_ yourself that you're getting more done ... but you'll actually be less sharp, less productive, less healthy, and much less happy (seriously -- it has big effects on your mood).

Read a book like Maas's _Power Sleep_ :

[http://www.amazon.com/Power-Sleep-Revolutionary-Prepares- Per...](http://www.amazon.com/Power-Sleep-Revolutionary-Prepares- Performance/dp/0060977604/ref=sr_1_1?ie=UTF8&s=books&qid=1202917354&sr=8-1)

I'd recommend a better book but I don't know of one yet. I spend my time sleeping rather than hacking sleep.

You can tinker with _when_ you sleep (using naps, etc.) to try and improve the quality of your sleep and adjust the times of day when you are most awake for maximum productivity. Just realize that you're basically rearranging your sleep and not magically reducing it.

If you can't find time to sleep the 8.5 hours that you need, you need to fix something else. Find a partner. Hire an assistant. Outsource. Prioritize. Postpone unimportant features. Get a better paying job with fewer hours. Play less World of Warcraft. Kill your television. Read David Allen or Tim Ferriss. Set noprocrast to numbers like "1024".

<comment><USER4> Good point. Your body needs what it needs. You can self-medicate with caffeine or other stimulants to try and hack the system, but they end up cutting in to your next nights sleep.

As an ER nurse, I've worked nights for 14 years. And, for the last 5, I've gone completely caffeine free. I've felt better than I have in years. It's amazing how easy it is to get into a (sleep deprivation -> stimulant -> sleep deprivation) cycle. Why? Because caffeine stays in your system for 24-26 hours. So, that cup of coffee that you had yesterday is still in your system when you go to bed the next night. And, the caffeine is stimulating you while you sleep preventing you from getting the normal cycles/amounts of the stages of sleep that you'd be in normally.

It takes a few weeks to come down off the caffeine addiction, but after you do, you feel so much better.

<comment><USER5> ~24 hours? Interesting. I've used coffee as a sleep aid: when I really need to go to sleep at X in order to get 8 hours before some important event, drinking coffee at 4 hours before X seems to help me sleep, due to the huge crash between 3 and 4 hours after the caffeine hits.

<comment><USER4> At least that's whay my Doc told me last time I saw him. Noodling around online, it seems that the half-life of caffeine can vary anywhere from 2-3 hours to 100 hours depending on the person, their metabolism and if they smoke or not.

</comment></comment></comment></comment><comment><USER6> 7-8 hours. Never used an alarm clock in my life. Wake up with the sun.

Here's a dirty little secret than runs counter to most of the advice in this thread.

(% of diet that's fresh fruit & vegetable) is inversely related to (hours of sleep needed)

There's some logic to this, too. Fresh fruit requires much less energy to digest --> less sleep needed. Try it for yourself. Eat no processed or cooked food for 3 weeks and see if your sleep requirements change. It usually works for me, until I drive by "Five Guys" and then I can't resist - back to 8 hours.

<comment><USER7> Do you have a source for that? The logic seems backwards. Per calorie absorbed, it takes more effort to digest uncooked foods, not less. Some fresh foods, like lettuce, actually take more energy to digest than you get out of them.

<comment><USER6> [http://www.amazon.com/Fit-Life-Harvey- Diamond/dp/1567315194/...](http://www.amazon.com/Fit-Life-Harvey- Diamond/dp/1567315194/ref=pd_bbs_sr_2?ie=UTF8&s=books&qid=1202949484&sr=8-2)

[http://www.amazon.com/80-10-Diet/dp/1893831248/ref=pd_bbs_sr...](http://www.amazon.com/80-10-Diet/dp/1893831248/ref=pd_bbs_sr_1?ie=UTF8&s=books&qid=1202949509&sr=1-1)

[http://www.amazon.com/Eat-Live-Revolutionary-Formula- Sustain...](http://www.amazon.com/Eat-Live-Revolutionary-Formula- Sustained/dp/0316735507/ref=pd_bbs_sr_1?ie=UTF8&s=books&qid=1202949530&sr=1-1)

[http://www.soilandhealth.org/02/0201hyglibcat/020121horne/02...](http://www.soilandhealth.org/02/0201hyglibcat/020121horne/020121toc.html)

[http://www.soilandhealth.org/02/0201hyglibcat/020125shelton....](http://www.soilandhealth.org/02/0201hyglibcat/020125shelton.pristine/020125toc.htm)

[http://www.soilandhealth.org/02/0201hyglibcat/020126shelton....](http://www.soilandhealth.org/02/0201hyglibcat/020126shelton.orthotrophy/020126.toc.html)

<comment><USER7> Those aren't very good sources. Amazon links are all weight-loss-oriented "pop" diet books. The genre is notorious for being full of inaccurate and misleading stuff.

On that other site, the author's other books include Natural Cure of Cancer. More hilariously, he has "D. P., N. D., D. C., D. N. T., D. N. Sc., D. N. Ph., D. N. Litt, Ph.D., D. Orthp." after his name.

<comment><USER6> What a strange comment from a hacker. Sounds like something I'd hear from a PHB.

What you call hilarious, many call life saving. I included the soilandhealth.org links for those who may want to learn something without buying a book. Those "golden oldies" are the based upon science that is still unrefuted by better minds than me and you. They are also the basis for many modern works.

Modern nutrition books HAVE to use the weight loss angle or publishers won't touch them. Not because the authors care as much as the public is so myoptic. (Hardly anyone cares about their health until they lose it. But almost everyone cares about their weight.)

Wanna pick a fight, why not start with Dr. Fuhrman? But first read the thousands of supporting documents footnoted on Pages 251-276 of Eat to Live. If you're going to call data that can save someone else's life "hilarious", you oughta be able to back it up.

</comment></comment></comment></comment></comment><comment><USER8> Studies have shown you need at least 8 hours of continuous sleep if you are on a traditional monophasic sleep schedule. Anything less and you start to accumulate "sleep debt" and performance decreases, among other things.

If you are very very serious about reducing total sleep time, you can attempt polyphasic sleep: <http://en.wikipedia.org/wiki/Polyphasic_sleep>

I recommend trying to find _Why We Nap_ by Dr. Stampi. Its the only detailed research on the subject. Basically, dont trust much of the info about polyphasic sleep around the net as much of it is false.

<comment><USER9> Steve Pavlina: <http://www.stevepavlina.com/blog/> did polyphasic sleep for a while, and does a good job relating his experiences.

His conclusion: It sucks because life isn't set up for that sleep pattern.

<comment><USER10> Sorry about the ad-hominem, but I think it's relevant to keep in mind that this is the guy that proposed that you could manifest one million dollars into your life just by declaring your intention everyday.

<comment><USER11> Well, last I heard he was making $40K/month and he had received valuations of $1-2M. Pav says some crazy stuff but it's usually backed up by his experiences.

</comment></comment></comment></comment><comment><USER12> It doesn't seem to matter to me how much I sleep, I just feel like crap when I have to wake up early, and for me that's unfortunately any point before 8 in the morning. Sometimes I sleep 9 hours, sometimes 6... the only way to not feel crappy is to wake up at 9 in the morning.

Same goes for waking up after, say, 9:30 because then I feel guilty about wasting so much time.

I have a job and since I need to be there at 9, I have to wake up at 7:30, which means setting the alarm to 6:30 and snoozing for an hour.

</comment><comment><USER13> 9 hours. It seems to correlate with the intellectual demands of whatever I'm working on at the time. If I'm learning a new technology or working on a thorny design issue, it can be as much as 11 hours a night. If I'm cranking out code for something I know how to do in my sleep (no pun intended), as little as 8.

I also noticed a big correlation when I was doing math competitions in high school. 9 hours or more of sleep and I could usually get a perfect score without too much trouble. 6 hours or less tended to cut my score in half.

For that reason, I try to avoid shortchanging sleep. I figure something important's going on upstairs, and I don't know exactly what it is but if it's missing, it costs more in productivity than it gains in time.

I've read that the amount of sleep people require varies a lot from person-to- person...I know some people can get by 3-4 hours a night, but I always feel like shit if I try that. Can't concentrate, wake up with an upset stomach, can't sit down to work. If I have 4 hours of sleep the next day is essentially wasted for me, I might as well have just pulled an all-nighter and gone to bed early the next day.

</comment><comment><USER14> I usually sleep about 7.5 hours. I don't know any hacks for sleeping less.

The best hack I know for getting more done in the same amount of time is to exercise intensely for 45 minutes to an hour every other day. It's best for me when my muscles reach exhaustion during the workout. I need about 30 minutes to an hour to recover, but my mind feels sharper and my enthusiasm is much greater for the rest of the day and the following day. I try to go first thing in the morning.

There's obvious health benefits, but I think the biggest benefit for me is psychological/emotional.

Thanks for the question! I think it may have inspired me to increase my waning dedication to exercise.

</comment><comment><USER15> I seem to be an outlier. I need about 10 hours but can easily enjoy 12.

<comment><USER16> Well, outlier or not, you're not alone! I'm exactly like you on this aspect.

<comment><USER17> And so am I :-)

</comment></comment></comment><comment><USER18> someone needs more sleep:-). The question you are asking is how do you get more done, how do you be more productive?

Take care of the usual suspects -- diet, exercise, sleep. Everyone needs different hours of sleep, so don't use that as a metric. The hours you are awake, make sure you are highly focused.

The other things that helps me is eating a light dinner (sometimes mostly soup) taken 3-5 hours before I hit the bed.

In addition, here are some excellent articles that should get you started.

1\. Be an early riser: Steve Pavlina -- [http://www.stevepavlina.com/blog/2005/05/how-to-become-an- ea...](http://www.stevepavlina.com/blog/2005/05/how-to-become-an-early-riser/)

2\. Take care of your health (diet & exercise), here's Gerry Weinberg's* notes on health: -- [http://www.developerdotstar.com/printable/mag/articles/weinb...](http://www.developerdotstar.com/printable/mag/articles/weinberg_healthybody.html)

3\. The Programmers' Stone talks about meditation, diet and sleep -- [http://the-programmers-stone.com/about/what-to-do-per-indivi...](http://the- programmers-stone.com/about/what-to-do-per-individual/)

* -- as a side note I highly recommend Gerry's book on technical leadership & secrets of consulting

good luck!

</comment><comment><USER19> About 8.5 is my ideal amount.

On the average day I sleep about 7.5. I can sleep unlimited amounts without any of the negative effects people mention, but if I sleep less than 7 it is really noticeable. I also can stay up several days pretty easily, but then I require a bunch of sleep to catch up, so it is pointless.

The sleeping unlimited amounts is really quite great for long flights or bus rides - I can just sleep for 20 straight hours.

<comment><AUTHOR> woah, impressive. I wish I could sleep that long in the plane. So if you don't use an alarm clock you sleep for about 20 hours?!?! Even if you aren't specially tired?

<comment><USER19> Absolutely. If I don't use an alarm clock I sleep a really long time.

I was at my brother's place for the holidays, arrived well rested, and nobody woke me up the next day and I didn't have an alarm. I slept about 15 hours until the baby crying woke me.

</comment></comment></comment><comment><USER20> 6-7 hours.

i find the trick is to sleep, whenever you are tired, take naps, and don't try to fight it. don't use alarm clocks, and don't lie in bed. you should either be asleep or awake, but don't lie in bed trying to decide. i also found that having a bedroom face east, does wonders for your biological clock and keeping it really regular.

</comment><comment><USER21> I need about 9 hours, more if I've skimped lately and less if I haven't. I have an alarm set for 8AM but that's only because my work time is not entirely flexible. I'd probably wake up between 9 and 10 if I could set my own schedule. I could probably cut this down a little bit by improving my sleep quality (I often wake up at 4AM and can't get back to sleep), but I haven't really investigated that fully.

But to step back a level, there are probably other time sucks you could cut back on other than sleep. For me those things are surfing pr0n and the sort of unfocused yak shaving that could be avoided by just getting enough sleep.

Cutting back on sleep seems like denying yourself something pleasurable that your body needs anyway. It's like trying to not masturbate.

</comment><comment><USER22> I need about 7 hours, my girlfriend needs 8-10, so we tend to compromise somewhere in the middle, with me continuing to read for a while after she's fallen asleep. I must not sleep much longer than 8 hours though, or I end up lethargic and unproductive and also unable to fall asleep the next night.

For me, the main sleep-related productivity boosters are making sure I _can_ and _do_ actually sleep, which took me years, (lying awake until 4am+ sucks big time) and making sure I'm ready to work at about 8-8:30 in the morning. 8:30 to 11:30 easily is my most productive time of day, probably 2-3 times as productive as other times.

I wouldn't bother trying to reduce sleep time. Optimise your awake time for happiness and productivity.

</comment><comment><USER23> Related PG quote: <http://scrapbook.akkartik.name/post/7867532>

Also cited at <http://news.ycombinator.com/item?id=97829>

</comment><comment><USER24> In college, I experimented on myself to see how much I needed. I found that <5 hours over time led to bad things for me (hallucinating, shaking), and surprisingly that >7 made me groggier than anything in between 5 and 7.

So that's what I shoot for.

</comment><comment><USER25> I usually sleep 6.5 hours each night. I don't have a set "bedtime," but I'm awake every morning at 07h30.

One of the most important things that you can do is just get up, once your alarms rings don't hit snooze, just get up! It's easier once it becomes a habbit.

I usually drag myself out of bed with my blanket, turn on the kettle and do some stretching on the lounge floor. I drink tea, eat cereal and then I shower.

</comment><comment><USER26> If you procrastinate your tasks, it means you sleep not enough. That's all.

<comment><AUTHOR> How come? Can you explain?

<comment><USER20> i don't think he meant long term procrastination, but rather daily procrastination. if you stay in bed, then you may need more sleep in your week.

once i wake up, any additional sleep is usually meaningless, i find a nap after lunch to be of much better use to me.

<comment><USER26> I meant short time procrastination as an indicator of sleep deficit. It's the best indicator you sleep not enough. You should pay some bill today but you can't find enough energy to do it (you can also feel strong aversion to do it) so you move this task and three other tasks to the next day. Ask yourself if this already happened.

There are some techniques by ex. some very intensive buddhist meditations (you can't perform in normal daily life) which can help you slow down your metabolism and so also need for sleep and eat without impact on your health, or techniques how to wake up exactly at 7AM (it's the best time IMO) without alarm clock.

</comment></comment></comment></comment><comment><USER27> I used to brag about how little sleep I've gotten, but lately I've seen that as much more of a short-coming. I've been able to measure my productivity on weeks where I've had good nights' sleep and weeks where I haven't, and even though I maybe work more with less sleep, I accomplish much less.

</comment><comment><USER28> 6 hours on average. Lately, I've been staying up to 2-3 am and waking up between 8-9 am. I'd like to shift that an hour earlier, but it's been hard to break the habit. I never napped before, and generally don't like to, but I'm finding now that it helps if I take a short 30 minute nap at some point of the day.

And I work from home, which makes this schedule possible. I tend to take about an hour after waking up to get started working and then stop work from around 6:00 pm to 10:30 pm to be with my wife and daughter. Then back to work when everyone goes to sleep. So that's 8-9 hours during the day and another 4 hours or so at night.

Before I got married I would sometimes go on really long working binges of like 16 - 20 hours or longer and then take a day or so off. Honestly, I prefer working in spurts like that.

</comment><comment><USER29> What is it with all these ASK YC lifestyle questions? Are we trying to define success in terms of things like sleep/watches tv?

Ah most hackers get 6 hours of sleep! I should too then my startup will succeed.

Sorry, but seriously... A few are kind of interesting, but how many more of these questions are to come?

<comment><USER10> _When art critics get together they talk about Form and Structure and Meaning. When artists get together they talk about where you can buy cheap turpentine._ \- Picasso

These days I was asking myself about how to clean my LCD screen and was hesitant if that was 'serious' enough to ask here. I was very relieved when I found someone else did.

You admit a few of these mundane questions are 'kind of interesting'. I guess all of them are interesting to some of us.

I see no specific problem with this. I'd let the usual voting mechanism take care of it.

<comment><USER29> It just reminds me of the endless "Vote up if.." that plagues Reddit.

</comment></comment></comment><comment><USER30> Different people do need different amounts of sleep, but also, the same people will need different amounts of sleep at different points in their life. Young children don't need as much. Teenagers need quite a bit because their body is growing rapidly. College level people through their 30s can usually get by with little sleep, then you need more as you get older.

I try and shoot for around 8 hours of sleep each night. You could argue that I could get more work done if I only got 5 or 6 hours, but the quality of the work would not be the same. I also find that going to bed at 11 and waking up at 7 is not the same for me as going to bed at 2 and waking up at 10.

Einstein and Donald Trump supposedly needed very little sleep which is why they could work so hard.

<comment><USER31> _"Einstein and Donald Trump supposedly needed very little sleep which is why they could work so hard."_

Interestingly, I read in a magazine from my country that Einstein slept at least 10 hours each day (and more if needed).

So, reading your statement, I decided to search more about this typing "einstein hours of sleep" using Google.

I found some links like:

 _"... while others have been known to require 8 to 10 hours (such as Albert Einstein)."_ \- in <http://webhome.idirect.com/~readon/sleep.html>

_"She points out that Albert Einstein sleep nine hours a night and was still able to get plenty done."_ \- in <http://evenstaronline.com/resources.html>

_"Einstein, on the other hand, demanded 10 hours of sleep every night for himself."_ \- in <http://www.quickiesheets.com/>

I'm not sure if this is really true, but I do believe that a lot of hard work people can easily sleep during 10 hours.

<comment><USER3> Misdirection. If you accomplish enough when you're awake people will _assume_ that you must not sleep.

</comment></comment></comment><comment><USER32> _"... By reducing sleeping hours I hope to be able to do more everyday. I know that some people need only 4h sleep and they are full of energy. I wish I could do so but I usually need 8.5 hours. I would like to know how many hours you guys sleep and if you have some tips to reduce sleep time. Do you think we are "born" with a needed amount of sleep or can we change it? ..."_

Sleeping 4 hours a day and feeling refreshed! Fatigued more like it. I certainly don't believe it. I've had stretches of months with only 4 hours sleep per day. I functioned but only at a base level. I didn't feel refreshed staying up 76hrs at a time. [0] For me and (we are all individuals) I need a good 8Hrs. If I don't, I'm one sorry mess to work with. Communication is by grunt.

      With rest, bit of exercise, food I work far better and do tasks far better

You need sleep. If you don't get enough sleep there is enough studies [1] to suggest performance at a lot of levels is severely reduced. Sleep deprivation is also form of mental torture. I don't know why anyone would want to have less sleep and as a result do things worse than they can.

      Trying to avoid sleep is a symptom

What is the real problem? Are you trying to do more with the time you have? Is it a time management issue? Is it an issue of living far from your work and travelling? Do you have poor sleep hygiene? Do you work in a job that _"demands"_ so much it requires you to miss something so basic as sleep?

      Is your boss torturing you?

Re-define the problem. Is it sleep you need to miss out on or is it something else?

[0] 3 days doesn't sound like much bit it is. An interesting experiment was to find ways to keep me awake. Funny but some Yoga & breathing worked a charm. Another thing is I learnt how cat-nap. Fall asleep, deep sleep at a moments notice. Day or night.

[1] BetterHealth, Victorian Gov, "Sleep deprivation" ~ [http://www.betterhealth.vic.gov.au/BHCV2/bhcarticles.nsf/pag...](http://www.betterhealth.vic.gov.au/BHCV2/bhcarticles.nsf/pages/Sleep_deprivation?OpenDocument)

</comment><comment><USER33> Varies by how long I've been awake. 5 - 6 hours on weeknights. 8 - 9 on weekends (but the entire 'day' - from time I woke up on Friday to time I wake up on Saturday, for instance - will be longer than 24hrs total). I can get by on 4 or 9, but usually less than 5 for 2 days in a row or more than 9 under any conditions and I feel like hell all day. When I have extended periods (more than 5 or 6 days) where I have no particular reason to get up at a certain time, I fall into a sleeping pattern essentially the same as the '28 hour day / 6 day week'. My sleeping habits have been about the same since puberty, and my mom's are about the same as mine (my dad sleeps about 9hrs a night).

</comment><comment><USER34> 2-5 hours a night, but I've only been doing that for the past 4 years.

My family members have seen sleep specialists, and according to them, the "people need 8 hours a night" argument is not true for everyone. Different people need different amounts. And if you actually read the research papers (it's been a couple years, so I'm not sure of links), scientists don't even know with 100% certainty what the purpose of sleep is.

However, that being said, there was a study done recently showing a correlation between getting less than 5 hours a night and heart problems later on in life. This has prompted me to start averaging closer to 5 hours than 2 hours lately.

</comment><comment><USER35> Let your body regulate your sleep, it's his job, just trust him and let it go and you'll be surprised at how much good he is at it. No expert can beat your body in this field.

Thinking about how much time and how you should sleep just brings an unnecessary cloud to your consciousness, wich is a limited and precious ressource. Keep the sky clear, focus on your objectives, be passionate about them and your body will just follow and gives you what you need. In return just listen to him and sleep when you feel tired. The quality of your sleep will be astounding.

</comment><comment><USER36> As the father of three young children who _finally_ are all _usually_ sleeping through the night, I am all too familiar with the difference between four, six, and seven hours of sleep.

I haven't tried anything fancy like polyphasic sleep, but I can say that simply "reducing sleeping hours" is not going to make you "able to do more everyday". It's going to make you spend more time staring at your monitor going "uuuhhhh".

</comment><comment><USER37> 6 hours usually - 7 if I'm lucky. Can't usually get to sleep before 1am - usually the kids are up by 7, I can sometimes stay in bed until 8. I wish I slept more actually - I really sometimes do feel like I am brain damaging myself. But I try and take a nap around 7pm usually - a half hour or hour while the kids go to bed - then I get up - watch TV and hang out with the missus, and get to work.

</comment><comment><USER38> Averaging 5.5 hours right now (with the help of 3 cups of Earl Grey and 2 hard-core commute bike rides each day up beyond category climbs). But this little sleep is not recommended except during a definite deadline after which one can recover. My average without pressure is 6.5 to 7 hours, Studies seem to show that 7 hours is a good healthy amount of sleep.

</comment><comment><USER39> I find it depends on whats on my mind. Many times I will wake up earlier then I wanted and cannot get back to sleep because I start thinking of things I need/want to get done. Currently I probably get around 6 - 7, 8 would be a good sleep and 4 - 5 hours on a bad night... I wouldn't worry about it too much, even sleeping 9 hours leaves 15 hours for the day.

</comment><comment><USER40> 6hrs - <USER2>

Something that got engrained in me, is that you tell yourself what time you are going to wake up, and then you make it standard, 7 days a week. Your body will adjust quickly and you will be tired when you need to be tired. Also sleep in 90 minute cycles, so I go to bed around 1A every night. if you still feel really tired during the day, take a nap < 20mins.

</comment><comment><USER41> 4-6 hours. every week or two i get a night of 7 or 8 to catch up. can't say its the healthiest thing but i'm still productive. the more annoying part is that my hours are slowly shifting around i've been going to sleep at 10am sleeping till 2pm these days and its my second time all the way around 24 hour clock in the last 3 months :(

</comment><comment><USER31> 9 hours. But I can easily sleep up to 10 hours!

Anyway, I don't care about my time of sleep if I can be very focused in my work for several hours. And this does happen often (when I'm not reading News.YC, heh).

I believe there are enough hours to work each day if you are really focused in what you do and if you're really feeling rested with your sleep time.

</comment><comment><USER42> 5-6 hours a night, I use up until 12 or to work and then wind down for an hour or two playing games or watching a movie with my wife

I should be getting more, but there is just too much to do and not enough time to do it all in.

8:30-9 commute, 9-5 work, 5-6 commute, dinner, then work again on my startup, then some games for the icing on the days cake.

</comment><comment><USER43> I was able to manage 3-4 hours sleep to be able to continue learning outside of my 9-5! My first week of doing this resulted in a onversation with my manager telling me to shape up or ship out. I was okay afterwards. The human body is a wonderful thing , it seems to adjust to whatever you throw at it!

<comment><USER41> agreed. i was working co-op 9-6 then my startup 7-4am for 4 months. at first it was tough but once i adjusted no one at work noticed.

</comment></comment><comment><USER44> 4-6 hrs + amphetamines for my ADD. on the weekends when I don't take my speed I can sleep for about 12 hours.

<comment><USER45> I'm curious if you started taking those as an adult or a child and if you wish it was one way or the other.

<comment><USER44> adult. and I'm happy I waited. the effect on me now is indistinguishable from drinking coffee all day only it doesn't give me the shits. I'm at the maximum legal dosage at 90 milligrams a day of adderal.

</comment></comment></comment><comment><USER46> I think it also varies by events. An exciting project that's nearing crunch time can get me running on just a few hours, the eyes snap open at 6:15 and life is fun (or...) til 2am. But don't try to keep running at that pace more than a few weeks if that long.

</comment><comment><USER47> If I wake up by eastern light: 6-7 hours. If I try to sleep through: 9-10 hours; sometimes more.

Sometimes I feel like I have very 'important' dreams that never resolve themselves. This keeps me in my bed for a _long time_.

</comment><comment><USER48> About 8-9 hours. I strive to sleep enough, and have noticed that trying to cut on sleeping does not work for me. I can sleep even longer, especially if I don't have any interesting/urgent tasks to accomplish.

</comment><comment><USER49> I usually sleep 6-7 hrs, but I need 7.5 to be at my best. I wake up at 6:45 normally, 6:30 this morning to shovel snow.

If you are at your best after 8.5 hrs, listen to your body and don't try to reduce sleep time.

<comment><USER50> "6:30 this morning to shovel snow."

... and you guys were trying to convince us that the NE isn't so bad?;-)

<comment><USER24> Shoveling snow is my favorite chore. It's quiet, solitary, beautiful, moderately but not overly hard work outside.

<comment><USER6> Shhh! If this gets out, the fitness industry is in BIG trouble. No machine, no matter how expensive, provides better exercise for the human body.

Oh, and you don't even need snow...

<http://www.shovelglove.com/>

</comment></comment></comment></comment><comment><USER51> I did polyphasic sleep. Three days. Got a stomach ache and colitis...

Don't recommend it.

<comment><USER11> The first week is a $#%^$#^@$%@@#$% pain. The trick is to train yourself to fall asleep quickly (5-10 min). This takes tinkering (link below). Now, especially if I'm in one of my three comfort places (bed, couch, or car), I know can fall asleep in 5 minutes or so.

Another key is DON'T try to sleep for more than 30 minutes. The deeper you fall asleep, the harder it is to get up. If I snooze my alarm even once for 10 minutes, I'm probably going to be too asleep to bother getting up when that 10 minutes is over.

The good news is that my experience (Steve Pavlina echoes this) is that once you train your body to work on the schedule, then even if you revert to a normal schedule, you can switch back to polyphasic sleep without having to go through the painful first week again. Right now I sleep polyphasic 5-6 days a week and have 1-2 days a week where circumstances prevent me from napping during the day and I then take a full night's sleep at night. Interestingly, I feel terrible after the full night sleep but pretty darn alert during polyphasic sleep.

Here are some of my experiences:

[http://www.pchristensen.com/blog/articles/category/polyphasi...](http://www.pchristensen.com/blog/articles/category/polyphasic/)

[http://www.pchristensen.com/blog/articles/sleeping-in- your-c...](http://www.pchristensen.com/blog/articles/sleeping-in-your-car- polyphasic-sleep-tricks/)

[http://www.pchristensen.com/blog/articles/what-happens- when-...](http://www.pchristensen.com/blog/articles/what-happens-when-you- oversleep-during-polyphasic-sleep/)

<comment><USER8> Agree with everything you said. I also think its easier to "ease" into the schedule. Keep a few hours of core sleep at night and still take your 30min naps every 4hrs until you feel like you're starting to get on the schedule. Then shrink and eventually eliminate the block of core sleep and you're there. Its never perfect, but at least it helps with the brutal agony of the adaptation period.

The biggest benefit of polyphasic is not squeezing every possible minute of awake time. Its the improved concentration and mood. If you want to leave 3-4hrs of core sleep at night thats perfectly fine.

</comment></comment></comment><comment><USER52> I typically get 6-7 a night. If I'm going to be tired it's usually during the day; inevitably, even without much sleep (or coffee), I really wake up around 11pm

</comment><comment><USER53> 5-6 on weeknights, 7-8 on weekends. Wake-up time is all across the board, which is not a good thing, but I spend a lot of time in different time zones.

</comment><comment><USER54> 6 hours on average. My dogs don't let me sleep in, my girlfriend doesn't let me sleep early, my job doesn't let me sleep during the day.

</comment><comment><USER55> The less you exercise, the less your body needs to recover. So you can balance your health and sleep time depending on your goals.

</comment><comment><USER56> 5.5 hours, out of necessity. I usually oversleep during the weekends. It is a poor compensation, but it is what I can do.

</comment><comment><USER57> i slept 12 hours out of 85 this week.. but then caught up just now so it's 25 out of 100 - or averaging 6 hours a night. i can't fit my sleep within a standard 24 hour period - in particular i find it hard sleeping twice within 18 hours. but on average i find i need to catch up to something fairly standard.

</comment><comment><USER58> Lately, about 4 hours a night. With a full night rest every 3 days or so.

</comment><comment><USER59> 7-8 hrs

</comment><comment><USER60> Recently... ~7 hours

Unfortunately those 6 hours have usually been 6AM to 1PM...

<comment><USER60> And apparently I can't do simple math. Those _7 hours_.

</comment></comment><comment><USER61> 4-5 hours per day.

<comment><AUTHOR> Have you always sleep that few?

<comment><USER61> No only recently, like the last 2 months. Before that 8 hours, before that, 12(when I didn't work).

<comment><USER62> Congratulations on the new baby. :-)

<comment><USER61> yeah I named him remindsyou.com

</comment></comment></comment></comment></comment><comment><USER63> Rarely more than 9, rarely less than 6.

</comment><comment><USER64> I usually sleep about 7 hours.

</comment><comment><USER65> i get about 8. try taking power naps, those will boost your energy.

</comment><comment><USER66> 8.5

</comment><comment><USER67> There is no general rule here:

I know persons who need at least 8 hours of sleep, and I know others who are more fortunate and only need about 4-5 hours.

It depends mostly on how sane you are in general (last not least: how your infancy has been: very, very important!).

<comment><AUTHOR> Can you explain on how you think your infancy will influence your sleeping hours? You mean if you are used to sleep much or not in your infancy?

</comment></comment><comment><USER68> I work crazy hours, but usually still manage to sleep 8 hours or so, minus when I'm really excited and can't sleep at all.

<comment><USER69> fyi: you're probably getting modded down because you add a signature to your posts (which people avoid, by convention, on news.yc)</comment></comment>


Ask HN: Splitting your time between reading, writing, and programming - <AUTHOR> I've been looking to write a series of posts for some time now on a specific subject and I realise I've been seduced by that all-to-alluring siren call of reading widely under the guise/excuse of "doing my research".
Yes, to write well you need to read widely, but there comes a point when you have to do the writing.  Indeed, some might say that reading widely simply pollutes your thoughts, so you add less and regurgitate more.  (You might catch a sense of "Unaccompanied Sonata" by Orson Scott Card).
So I'm setting aside my reading for a while and getting down to writing.  When I come back, though, I'd love to see people's experiences in how they split their time between reading (for research or otherwise), writing (documentation, fiction, blog posts), and programming (for themselves and for others).
I can't remember who is was, but some time ago a read an article in which someone said that it's impossible to say what proportion of time they spend on each, because they have so much to do that they only now engage in activities that count in more that one category.  If you know of that, I'd appreciate a link.
So - what do you do? <comment><USER2> panic. if i don't get around to reading a book, like maybe if it's too boring or something, my dog will eventually chew it up. saves a lot of time.

If i were god and i were to make intelligent life in my image, i would give it the ability to forget things that it has been told. this seems like a weakness, but I think the ability to forget unimportant sayings is more useful than the ability to remember important sayings.

it's rather convenient then that books will eventually break down and have to be rewritten by the next generation of writers, who decide what is and isn't important. our ideas evolve and change with us, and the act of preserving them kills this evolution.

however the nature of books has changed: books distributed between many hard drives last longer than books on paper. obviously, everyone now realizes that there are way too many books around and not enough time in the world for anyone to read even a tiny fraction of them. this problem worsens for future generations as technology improves.

so there's this robot in asimov's the last question who will eventually read all the books for you and understand everything, and that's supposed to be god or whatever. but it doesn't exist, so do not read for the sake of relieving stress about "things that will never be known", "things that will be lost to the winds of time" or "things I would enjoy to know, but I just don't have enough TIME!! [https://www.youtube.com/watch?v=UAxARJyaTEA"](https://www.youtube.com/watch?v=UAxARJyaTEA"). read what you have to and nothing more.</comment>


Goldman Sachs: Bitcoin Is Not A Currency - <AUTHOR> http://techcrunch.com/2014/03/12/goldman-sachs-bitcoin-is-not-a-currency/

<comment><USER2> "'On net, more than taking off as a widely-used alternative currency, it is much more plausible that bitcoin eventually has a significant impact in terms of its innovation on payments technology, by forcing existing players to adapt or coopt it,' the authors write."

Yup.

</comment><comment><USER3> The inventor of BRICS with hedges in the other hand? Say it's not so!

</comment><comment><USER4> My irony meter just pegged: Goldman Sachs is sanctimoniously criticizing Bitcoin as an unreliable medium of exchange, a shaky institution not to be trusted.

Let's all savor this moment together.

<comment><USER5> Yes this is ironic.

But let's not judge the article and assertion based on our preconceived bias against Goldman Sachs. I think that their conclusion "We would argue that bitcoin, and other digital currencies, lie somewhere on the boundary between currency, commodity and financial asset" makes a lot of sense.

Really, Bitcoin does have more similarities to a commodity than a currency (especially a fiat currency). It's fungible, untraceable, and unregulated.

<comment><USER4> All true. One difference between Bitcoin and dollars is public perception driven by multiple forces -- experience, some untested assumptions, and social expectations. Alto TBTF (Too Big To Fail) plays a part -- we're not going to allow dollars to fluctuate too wildly and destabilize the economy.

But another difference between Bitcoin and traditional media of exchange is that Bitcoin relies on very good, utterly reliable software, and that doesn't exist at the moment.</comment></comment></comment>


Ask HN: Learn Philosophy The Hard Way - <AUTHOR>

I am interested in learning all of the classics in Philosophy whether western or non western ,ancient and modern as a long-term project.Any suggestions how or where i should start? <comment><USER2> I like this book: [http://www.amazon.com/Introduction-Philosophy-James- White/dp...](http://www.amazon.com/Introduction-Philosophy-James- White/dp/0495158631)

It has a collection of smaller readings so you don't get bored and/or get confused getting through a 500 page tome on your first go. The subjects covered are fairly interesting (epistemology, philosophy of mind, etc.), gathering material from a mix of time periods.

A problem with a book like that is that it doesn't have commentary built-in, so if you misread something and run with it, you might not realize it in the future, if ever. I used the above book in a class, which allowed me to bounce ideas off of other students and, of course, the professor. Consider getting a book more along the lines of a textbook when you're starting out so that you have readings along with commentary by a person knowledgeable in the subject.

Oh, and the Stanford Encyclopedia of Philosophy is useful: <http://plato.stanford.edu/>

</comment><comment><USER3> Start with Nietzsche or Plato. (Easy reading) Avoid Kant for now. (Hard reading) I'd recommend an overview-type book first, try _Archetypes of Wisdom_ , or even the audiobook series _Giants of Philosophy_.

[http://www.amazon.com/Archetypes-Wisdom-Introduction- Douglas...](http://www.amazon.com/Archetypes-Wisdom-Introduction-Douglas- Soccio/dp/0495603821/ref=sr_1_1?s=books&ie=UTF8&qid=1341872129&sr=1-1&keywords=archetypes+of+wisdom)

[http://www.amazon.com/Giants-Philosophy-Series-Audio- Classic...](http://www.amazon.com/Giants-Philosophy-Series-Audio- Classics/dp/078615893X)

Also, working chronologically is probably a good idea. You'll get to see how ideas have developed (and stayed the same) over the ages.

Source: philosophy major.

<comment><AUTHOR> I have cleared all of Plato's Dialogues and i am currently interested in a decent map of all other original works.

</comment></comment><comment><USER4> I might get some flack for this, but, honestly, read Ayn Rand's classic novel, "Atlas Shrugs" because its epistemology (theory about how we know things) is very much from Aristotle and Nietzsche (by her own description of her influences). I don't 100% always agree with her politics, but in terms of basic philosophical ideas, her work is a fun and easy way to get acquainted with mainstream classic Western philosophy. Again, not to get into politics, but if you want an easy way to understand a lot of what Aristotle was saying, her novel "Atlas Shrugged" really draws on these basic ideas (Law of Non- Contradiction, and so on).

</comment><comment><USER5> One suggestion is to try and first familiarize yourself with the different types of philosophy. Philosophy is a pretty broad topic, so find something that is interesting to you (such as metaphysics, epistemology, ethics, etc..) and then read the relevant philosophical works. A great resource to get a general overview of many philosophical concepts is the Stanford encyclopedia of philosophy: <http://plato.stanford.edu/>

</comment><comment><USER6> I try to re-read "Perpetual peace" from Kant, as I had to go through that book while I was student. I think it has some deep insight, so it's a book I'd recommand, even though it's not the easiest one to read.

</comment><comment><USER7> For Western philosophy, you should read Copleston's History of Philosophy. It's probably the most comprehensive treatment of western philosophy out there.

<comment><USER8> Copleston is a good reference, but it's not a substitute for reading the original works, particularly given his (understandable) bias toward reconciling the history of Western philosophy with Roman Catholic theology; e.g.

 _"his_ [Giordano Bruno's] _condemnation for heresy was perfectly understandable, whatever one may think of the physical treatment meted out to him. His ultimate fate has, of course, led some writers to attribute to him a greater philosophic importance than he possesses."_

Furthermore, Copleston ignores non-western philosophical thought entirely.

<comment><USER7> No, it's not a substitute - it's an aggregation, or survey if you will. At 11 volumes, it's still quite lengthy. Telling someone to read everything ever written by an author mentioned in Copleston is on the order of casually suggesting they get a Ph. D - it's an insane amount of work.

And of course it ignores non-western philosophical thought: it's right in the title. You wouldn't get up in arms over a jQuery book completely ignoring C++ calling conventions.

</comment></comment></comment><comment><USER8> Start by reading philosophy. That's where to begin.

What matters is finding something accessible and interesting.

So long as it isn't Ayn Rand.</comment>


A theoretical physics FAQ - <AUTHOR> http://www.mat.univie.ac.at/~neum/physfaq/physics-faq.html <comment><USER2> This is a fun collection but recently I have been wanting to see how well different theoretical models express experimental data

If I want to calculate the efficacy of relativity where can I find observational data on mercury's orbit?

If I want to calculate the efficacy of quantised photons where can I find observational data on blackbody radiation?

If I want to calculate the speed of light where can I find observational data on io?

If I want to calculate the efficacy of quantum mechanical models where can I find observational data on qm phenomena?

Are there resources of others showing from experiment to theory with calculations of real data defending the theory's math

Or even just access to these and similar datasets?

<comment><USER3> I'm sorry, but usually people can't waste their time working in easy to understand datasets with a wiki for amateurs (for free), unless it's for some kind of teaching (that they're being paid for). If you're really willing to you can start studying some of the Physics you're talking about (honestly, any physicist could tell you still haven't), it's the easiest way to get to know which really old papers you have to check. Maybe you can do some lab work in an educational environment and learn what to do with raw data after you understand the experimental setup, what's being measured and how it's being measured: that's the key to know what you are doing. Modern big experiments, for instance in HEP, expect from you a significant effort and having to deal with particular frameworks, that means a few months full-time at least and you need people around that can answer your questions. I don't mean to sound harsh, but honestly your questions are too broad (it doesn't work like that), and imprecise... for instance, you don't "calculate the efficacy of [a theory]" in Physics, and data don't "defend the theory's math". Not at all.

<comment><USER2> I freely admit writing the op was difficult and I rewrote the questions many times editing out terminology.. if I'm still coming up short perhaps you could help

> you don't "calculate the efficacy of [a theory]"

How would you describe in a single sentence the growing precision of our calculation of the speed of light constant over the last 300 years?

> data don't "defend the theory's math"

How would you describe in a single sentence the way Einstein used Mercury's retrograde motion to assure himself of the advocacy of his theoretical mathematical model for gravitation?

<comment><USER3> >How would you describe in a single sentence the growing precision of our calculation of the speed of light constant over the last 300 years?

I don't know, first I'd talk about how it was discovered that light behaves like c really is a constant (that's not intuitive nor trivial). You could guess from Fizeau (1851) and Michelson-Morley (1887) experiments, but it wasn't really until the 1905 Einstein's paper that it was understood that you don't need aether, the speed of light can (and should) be a universal constant and it all makes sense.

>How would you describe in a single sentence the way Einstein used Mercury's retrograde motion to assure himself of the advocacy of his theoretical mathematical model for gravitation?

He shows (see here: [http://www.gsjournal.net/old/eeuro/vankov.pdf](http://www.gsjournal.net/old/eeuro/vankov.pdf)) that his theory (after reasonable approximations) predicts a precession of the perihelion of Mercury that agrees with the experimental result, then he stops. That's what you do in Physics: look, my nice theory predicts this observable in agreement with the experimental data. That's a very good sign, but the data could be explained by other theory as well. Data can "prove" that a theory is wrong (if your theory has falsifiability, as it should), but they can never show that your theory is all that there is, nor your maths... There are other theories of gravitation, for instance Logunov's, that are interesting and agree with data (more or less) but have a few problems with maths.

BTW, I don't think he ever really doubted his GR theory, it comes from a very simple, yet profound idea that once realised had to be right. You have to do all the technical work afterwards, that was difficult, but a few mathematicians could have done/did it (Hilbert). In any case the idea is to check your predictions with the measurements from more and more precise experiments to find out if you're wrong, not the other way around (that... well, I've met that funny epistemology a few times in social sciences.)

<comment><USER2> Why are you relying on strawmen?

> Data can "prove" that a theory is wrong (if your theory has falsifiability, > as it should), but they can never show that your theory is all that there > is, nor your maths.

Where you got '"prove"' and 'all that there is' I am unsure

My wording was:

op> how well different theoretical models express experimental data

Which mirrors your own reiteration of that point

> the idea is to check your predictions with the measurements from more and > more precise experiments

Which is literally what I was asking for: measurements from .. precise experiments

> predicts a precession of the perihelion of Mercury that agrees with the > experimental result

Right, where's the experimental data on the orbit of Mercury?

If you are unable to answer the question that's fine but as is I fail to see what you are trying to accomplish with your ire and misdirection

<comment><USER3> I'm sorry if I came across that way, didn't mean to. But you have to realise that it's tiresome all this new internet phenomena of laymen questioning the work ethics of actual professionals because they think they could possibly do better, if only etc. I don't usually comment on HN about Physics because... well, never mind, it really was a bad idea this time.

If you're interested in the data you can browse the references, go to the libraries (as physicists have to do even at college, because it's kind of hard), find out first what exactly you are asking... even mail someone. And you can also measure things by yourself, this is a free universe and everybody can study its properties (Mercury is out there and maybe you can afford a nice telescope). What is unreasonable, very unreasonable, self-entitled in my opinion, is expecting that experimental physicists provide some kind of repository of (internal-notes redux) data for casual readers of pop sci. That would cost their time (or some overworked PhD student's) and project money, the bad news is no one is willing to do that nor paying for it. It's not that there's some kind of conspiracy, it's that people are actually busy working.

<comment><USER2> > laymen questioning the work ethics of actual professionals because they > think they could possibly do better, if only etc.

> What is unreasonable, very unreasonable, self-entitled in my opinion, is > expecting that experimental physicists provide some kind of repository

> It's not that there's some kind of conspiracy

You seem to be arguing with someone else

> I don't usually comment on HN about Physics because... well, never mind, it > really was a bad idea this time.

If you are knowledgeable on the subject I would encourage you to comment, but keep the comment on the topic being discussed

<comment><USER3> Well, I'll stay on the post topic. It's unlikely that you can get the lab notebooks from most of 20th century Physics, this is what you're really looking for. It's not that important, because once the results are published by a few different groups that don't trust each other and will scrutinize their peers' work, all relevant data have been measured again and again. If theories like Special Relativity were really wrong there would be consequences like having to close all particle accelerators because they wouldn't work. Many key experiments are routinely done as part of the university courses, and many results are also routinely used in other fields, engineering included. E.g. linearisations of Planck's distribution are done in Remote Sensing for estimating surface temperatures, they work great btw. We also understand light bulbs, pyrometers, infrared thermometers... -those work straight with Planck's Law, how else could they find the temperature-. There are GR corrections coded somewhere for your GPS to work, etc.

If by seeing "how well different theoretical models express experimental data" you're planning to apply idk assorted non-linear regression models from equations you're not familiar with to see which one has the minimum chi-square or something like that, well I guess that's what hobbies are for. Differences tend to appear at the limiting cases, there you need more Physics than Levenberg–Marquardt fun, so it's better to start there.

I have to warn you that your wording matches the usual stuff you get from Physics cranks (the bane of the trade), hence the knee-jerk reaction, sorry about that. I'll try harder next time.

<comment><USER2> it's for educational purposes

to express concepts like these to anyone interested using real world data to show why these concepts are important

Like why Newtonian physics is insufficient to explain Mercury's orbit

Or how infinitely divisible energy leads to the 'ultraviolet catastrophe'

Or how one can approximate the speed of light just using orbital data of io and earth (romer's initial method)

I can appreciate that my wording may have been ambiguous

Brevity can sometimes be the enemy of clarity but questions can help avoid assumptions

<comment><USER3> Thank you, I get it now. You're absolutely right and that could be really interesting. The problem is you don't usually have large sets of data in elementary uni labs, because of schedules really, but that would be the best.

I'm not an Astronomer (nor Astrophysicist, I know about GR coming from a Theoretical Physics bkg), so I suspect you could get more recent data, but a classic reference from the GR book of Weinberg is a paper from G. M. Clemence: [http://adsabs.harvard.edu/abs/1947RvMP...19..361C](http://adsabs.harvard.edu/abs/1947RvMP...19..361C) (it can be obtained if you look around, there's a similar free-to-read paper from the same Clemence: [https://www.jstor.org/stable/3143142?seq=1#page_scan_tab_con...](https://www.jstor.org/stable/3143142?seq=1#page_scan_tab_contents)) that has as reference this: [http://adsabs.harvard.edu/full/1943AJ.....50..126C](http://adsabs.harvard.edu/full/1943AJ.....50..126C) (full text), that quotes the Astronomical Papers of the American Ephemeris, Volume 11 (it says II, but it's actually 11), part I. Google is your friend (they've scanned those!) and you can find the data at [https://catalog.hathitrust.org/Record/000068403](https://catalog.hathitrust.org/Record/000068403). This is how a little of preliminary research works, you have to do it yourself all the time... Luckily now you don't have to go hunting for a paper copy without being sure about the contents all the time (although it still happens).

The classical mechanics calculation might be tricky, to say the least, as well.

For the UV catastrophe I've always liked the Jeans cubic cavity and the Gamow observation that opening an oven doesn't kill you. And of course, the fact that integrating Planck's law gets you Stefan-Boltzmann's, very neat result.

I should think about all this a bit more in order to give you better feedback.

</comment></comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER4> Don't limit yourself to this FAQ.

1\. Head over to physics.stackexchange.com.

2\. Sort all answers by votes.

3\. Start reading (read the corresponding questions first).

4\. Emerge three days later slightly enlighted with a stubble on your face.

5\. ???

6\. PROFIT!!!</comment>


John Horton Conway - <AUTHOR> https://www.scottaaronson.com/blog/?p=4732 <comment><USER2> Seems under a load, so here is archive URL just in case [https://web.archive.org/save/https://www.scottaaronson.com/b...](https://web.archive.org/save/https://www.scottaaronson.com/blog/?p=4732)

</comment><comment><USER3> > _" Apparently it was the coronavirus. Yes, the self-replicating snippet of > math that's now terrorizing the whole human race"_

Great analogy, except of course a virus is not _self_ replicating.

<comment><USER4> Or is more of "a piece of math" than anything and everything else.</comment></comment>


Quantum mechanics used for better random numbers - <AUTHOR> https://newatlas.com/quantum-random-numbers/54184/ <comment><USER2> Another example of physicists selling their basic research by linking it to cryptography in a way that makes no sense. Generating quantum random numbers is not solving any real cryptographic problems. It's just marketing ploy or ignorance.

DJB: Is the security of quantum cryptography guaranteed by the laws of physics? [https://sidechannels.cr.yp.to/qkd/holographic-20180312.pdf](https://sidechannels.cr.yp.to/qkd/holographic-20180312.pdf)

DJB: Security fraud in Europe's "Quantum Manifesto" [https://blog.cr.yp.to/20160516-quantum.html](https://blog.cr.yp.to/20160516-quantum.html)

Schneier: Quantum Cryptography: As Awesome As It Is Pointless [https://www.schneier.com/essays/archives/2008/10/quantum%5Fc...](https://www.schneier.com/essays/archives/2008/10/quantum%5Fcryptography.html)

<comment><USER3> Regarding the last article: it is a little vague in its argument, and I definitely have a few questions:

Is it true that the encrytion algorithms still aren't the weakest link for highly sensitive classified information (e.g. in the government)? (Or in similar high-secrecy situations, not the ones that an everyday person takes part in)

Also, if current methods aren't backed by rigorous mathematics, isn't that a risk in it of itself? So, while the benefit of having a more mathematically rigorous security protocol may not have practical implications, it would still be more secure, right? (Even if it isn't the top issue in most cryptography) It might not solve security's biggest issues, but I don't think it is claiming to do so, anyway.

The author is also fairly harsh in general on quantum computers. Note that they have made notable strides since 2008, and much larger computers have already been built --- they haven't performed a computation that classical computers would struggle with _, but they can certainly factor numbers larger than 15 (although you wouldn 't use a near-term quantum computer for this, anyway, as they will not be powerful enough anytime soon to factor interestingly large numbers, anyway). At the very least, it is outdated in that respect, and at worst, it's rude and being dramatic to catch people's attention.

_ At least, nothing that has been carefully analyzed in this respect and published.

<comment><USER4> _> Is it true that the encrytion algorithms still aren't the weakest link for highly sensitive classified information (e.g. in the government)? (Or in similar high-secrecy situations, not the ones that an everyday person takes part in)_

Yes. The weak link for cryptography is implementation. Implementation is insidious because it's easy to implement an existing cryptographic specification in a way that looks safe but which is completely broken. It's also an attractive exercise for people who know how to write software. In contrast, designing novel cryptography (especially public key cryptography) requires a very advanced understanding of mathematics and complexity theory before you can even get to the "seems convincing, but is actually horribly broken" stage. If you want to compromise a cryptosystem you attack the individual implementation, not the design specification that has withstood a generation of careful scrutiny by well-funded mathematicians and computer scientists.

 _> Also, if current methods aren't backed by rigorous mathematics, isn't that a risk in it of itself?_

I think Schneier probably shouldn't have written his point this way; in context he's referring to provable security. Provable security is a separate, complexity theoretic study. The mathematics underlying our cryptosystems is very well understood in the sense that we generally have a mature understanding of how difficult various intractable problems are. The difficult part is mapping that intractability to specific cryptographic properties in an adversarial model, such as existential unforgeability. For example, NTRU is a well studied, currently safe cryptosystem which didn't have any provable security metrics for at least a decade after it was invented.

Provable security does represent a risk, which is why it's always an active research topic. But _importantly_ , provable security exists within a _computational_ framework - it is not solved by proposals for quantum cryptography.

</comment></comment></comment><comment><USER5> Good hardware generators are based on Johnson–Nyquist resistor noise, that is just as unpredictable, and generated by thermal circulation of charge carriers in conductors.

In real life, RNG attacks are against the implementation not the noise source, even something as "predictable" as "atmospheric noise" is random enough for all practical applications.

<comment><USER3> Why is it just as unpredictable?

There are measurements you can make that could help you predict Johnson noise. For many quantum schemes, it's much tougher.

(Not that it is easy for an attacker to make those measurements in the first place, but it doesn't seem fair to say it is rigorously just as unpredictable)

<comment><USER6> Nope. Johnson noise is quantum mechanical (at least in significant part). If you use a good algorithm, you can sample a partial TRNG into an epsilon- perfect TRNG (as close as you'd like). Not to mention all of this is pointless since even if the noise were classical a few applications of strong hash functions (which is the normal procedure -- they're entirely practical) require would require computers using more energy than the entire universe has available you want.

<comment><USER3> I definitely appreciate now that there are good algorithms to make your random bits more random, and hash functions can help, but regarding calling johnson noise quantum mechanical: can you give one reference of a description of finite-temperature johnson noise in which at least 1 observable necessitates a quantum mechanical treatment? (I don't think it exists, given that it is a thermal phenomenon, but maybe I'm wrong...)

</comment></comment></comment></comment><comment><USER7> Is it really that relevant whether randomness is true* thanks to quantum effects rather than obfuscated-enough pseudo-random based on really hard to predict entropy sources; or is this more a PR stunt? I mean, is it realistic that someone would ever manage to predict e.g. electronic signal noise in a useful enough manner?

* To nit-pick, the question whether quantum mechanics are truly random boils down to Bell's theorem, which has been experimentally supported, but still leaves some loopholes open: [https://en.wikipedia.org/wiki/Loopholes_in_Bell_test_experim...](https://en.wikipedia.org/wiki/Loopholes_in_Bell_test_experiments)

<comment><USER4> It's relevant in an information theoretic sense. However modern security is explicitly computational rather than information theoretic, which means it's not relevant for modern security in any practical sense. For example one time pads are only really used (correctly and safely) by agencies like the NSA and GCHQ, and even then only for the strictest, "spare no expense" security requirements.

I'd personally be appalled to see a quantum random number generator utilized in a cryotosystem. Well understood cryptographic failures like nonce reuse and side channel attacks are still routine; I can't imagine the number of novel side channels and footgun opportunities that would be introduced with a cryptosystem utilizing this thing. The hardware, design and implementation requirements would add an enormous amount of complexity for an extremely small improvement overall.

<comment><USER3> Genuine question: why would switching out the source of random bits make for that much more complexity? The hardware is more complicated right now for sure --- do you mean to say that the work in checking the hardware doesn't have less obvious exploits (compared to simple Johnson noise measurements) is the tricky bit?

<comment><USER8> Because hardware and hardware connectivity can fail, and the one thing cryptography needs from the system CSPRNG is not having failure cases. Since past a threshold the quality of the entropy source does not in fact matter, no amount of added complexity, however marginal, has a positive return on investment.

</comment></comment></comment></comment><comment><USER9> People paranoid about randomness have been duct-taping ionizing radiation sources from smoke detectors to webcams for decades now. This is non-news.

</comment><comment><USER10> When you're generating random numbers from a physical source, how do you detect when there's some failure in the hardware or sensors that's reducing the randomness? Can you use redundancy so the probability of this is vanishingly low?

<comment><USER3> I always thought you did this by performing statistics on sample values to see if very unlikely correlations exist.

<comment><USER10> What I meant was happens if hardware passes such a test on release but then after months of use develops a fault?

</comment></comment></comment><comment><USER11> Anyone know a cheap DIY way to generate quantum-random numbers at home? For example, get a Geiger counter and wire it up to code that counts the milliseconds between clicks... something like that?

<comment><USER12> Yes: use your chip's generator through your OS's random number generator (urandom on Linux). The chip's thermal-noise entropy source is fundamentally based on quantum mechanics.

</comment></comment><comment><USER13> To all the people saying high quality random numbers are not important for crypto, there have been a number of important failures over the years due to semi-predictable keys. And there is no way to generate randomness in software, while quantum sources can be provably random.

It just makes the crypto system easier to reason about.

<comment><USER4> No one is saying high quality random numbers are not important for cryptography. We are saying _true_ randomness is unimportant and undesirable, given the comparatively enormous complexity required to achieve it. The modern conception of cryptography is explicitly that you do not need "true" anything - randomness, security, indistinguishability, unforgeability, etc. Everything is modeled in game semantics with a computational cost:benefit analysis for attackers.

Cryptographic failures with respect to entropy sources occur not because they aren't random enough, but because they're implemented incorrectly. When they're implemented correctly, they're fine, because this is a well studied problem for which we have a variety of useful solutions. This is why proposing a replacement source of entropy using quantum computers is ridiculous, because you would commensurately increase the complexity of the system into completely unknown territory.

This isn't exactly a controversial perspective. I don't know of a single reputable cryptographer who takes quantum cryptography seriously. I would be happy to learn of a few, but if you look at the research landscape you'll quickly see that proposals for quantum cryptography are disconnected from the academic cryptography community.

</comment></comment><comment><USER14> how do we decide or quantify that certain random numbers are good or bad?

if I flip a coin? maybe that's inadequate, but can we measure how much it is failing to be random?</comment>


Ask HN: I am a copy/paste programmer, is that bad? - <AUTHOR>

I wouldn't be able to write a simple HTML page from scratch. Google (more specifically Stackoverflow) is a vital part of my IDE! I've always sucked at remembering stuff but in compensation I got logical and analytical skills. I do not blindly paste the code, I do read it and see if it fits, but I would certainly have a bad time if not code references where around while coding. So, am I a bad programmer? Or is this way of programming more common than I think? <comment><USER2> I disagree with most people here. If it's remembering it's one thing. It just takes a while to remember certain things, but if you can't start out own projects or just write a project (or part of a project) that you feel like you know it may be a reason to worry.

But in the end it really depends on this. The problem is not the looking part, but if you have to copy stuff and can't start projects on your own, I don't know how that makes you a programmer.

Also it must be really hindering. What's important I guess is that it doesn't hinder you, that you are able to get into flow while programming, that you don't get stuck.

In other words. If you can't get into flow or if you don't understand the code it's a pretty big problem. If you are sometimes in flow and understand what you are doing it's nothing you should worry about. If you are in between it probably means you need more practice. For that maybe find something that interests you and write a small project (with as much looking as you like).

<comment><USER3> Do you use any 3rd party libraries?

</comment></comment><comment><USER4> > I do read it and see if it fits, but I would certainly have a bad time if > not code references where around while coding.

This is the most positive part of your copy/pasting practice: reading and understanding.

Reading the documentation alone is time consuming if the documentation does not contain example code, which visually put together what must be understood.

That said, looking up SO can also be a time sink: checking two or three questions until finding the correct question/answer. Maybe in no time [http://devdocs.io](http://devdocs.io) would have answered the question. I also have a private gist app to gather snippets that I can quickly search.

> So, am I a bad programmer?

I read that a lot, experts don't need to look up the documentation. I'm not sure how true it is. That said I recognize that knowing basics perfectly, common Object, Array & jQuery methods, common modules in ruby/python etc... helps to build things faster.

Having good tools helps a lot.

<comment><USER5> +1 for devdocs.io - very useful extension

</comment></comment><comment><USER6> That's normal don't let the online video tutorials fool you. They have it on another screen or a paper to make you think they are super genius by typing long snippets of code without even a typo.

</comment><comment><USER7> I often look up things as I jump between a couple different languages depending on what I'm working on. I'm not really looking how to do things, but more like how something worked, or maybe a more efficient way to do something. Usually if I'm going to copy/paste something it's just to paste into my code as a comment to use as an example. If I had to program without access to the internet, I'd need to have reference books around or I'd get stuck pretty quick.

</comment><comment><USER8> To be honest I think alot of programmers copy and paste, unless it is something that they use often. If there is a module that you rarely use, or have never used before, why would you know how to use it off the top of your head? Also, some things you may be able to do on your own but copy and pasting could save you the time that it would take you to type those X amount of lines.

</comment><comment><USER9> A great man by the name of Einstein said something to the effect of: "Never try to remember anything you can easily look up in a book." (paraphrasing here). I don't think I've ever met a programmer that codes complicated programs by memory alone.

</comment><comment><USER10> Every programmer probably does this.

If I see a function that works perfectly, is short and clean, and solves my problem, why not use it? That lets me spend less time reinventing the wheel and allows me to move onto more difficult problems.

<comment><USER11> It isn't fair to say that "Every programmer probably does this." I know for a fact I don't.

<comment><USER10> So what do you do? Study the code, close the browser, and rewrite it line for line?

</comment></comment></comment><comment><USER12> I don't think it's strictly bad. Having said that there's nothing more blissful than spitting out 100-500+ lines of code that work (or makes sense as an outline) without looking anything up.

</comment><comment><USER13> If you ever meet someone who says they can code with Spring without Google, they're lying.</comment>


Structure and Interpretation of Classical Mechanics - <AUTHOR> https://mitpress.mit.edu/sites/default/files/titles/content/sicm_edition_2/book.html <comment><USER2> This is a great book but a bit dense first. At a high level it goes through physics with an optimization viewpoint, as in find the actions that minimize a system's energy to figure out how a system will evolve.

I would strongly suggest you learn Lagrangian and Hamiltonian Mechanics from this book first [1] since it comes with many more illustrations and simple arguments that'll make reading SICM much easier. If you don't have time to read a whole book and want to get the main idea I've written a blog post about Lagragian mechanics myself [2] which has made it to the front page of Hacker News before. The great thing about SICM is that it's a physics textbook where the formulas are replaced by code [3] which you means you can play around with your assumptions to gain intuition for how everything works.

IMO I believe in introductory physics we overemphasize formalism over intuition and playing around with simulators is a truer way to explore physics since most physical laws were derived via experimentation not derivation. Another book that really drives this point home is [4]

[1] [https://www.amazon.com/Jakob- Schwichtenberg/dp/1096195380/re...](https://www.amazon.com/Jakob- Schwichtenberg/dp/1096195380/ref=tmm_pap_swatch_0?_encoding=UTF8&qid=&sr=)

[2] [https://blog.usejournal.com/how-to-turn-physics-into-an- opti...](https://blog.usejournal.com/how-to-turn-physics-into-an-optimization- problem-11b3fbf83062?gi=b6b2beb291f5)

[3] [https://github.com/hnarayanan/sicm](https://github.com/hnarayanan/sicm)

[4] [https://natureofcode.com/](https://natureofcode.com/)

<comment><USER3> "find the actions that minimize a system's energy" That sounds incorrect.

The path taken by the system between times t1 and t2 and configurations q1 and q2 is the one for which the action is stationary (no change) to first order. [https://en.wikipedia.org/wiki/Principle_of_least_action](https://en.wikipedia.org/wiki/Principle_of_least_action)

The reason for this is quantum mechanics [https://en.wikipedia.org/wiki/Path_integral_formulation](https://en.wikipedia.org/wiki/Path_integral_formulation)

<comment><USER2> Yes you're correct, I'm just giving the intuition that I found helpful to understand the Principle of Least Action.

</comment></comment></comment><comment><USER4> I love what I've read of this book, but found reading the HTML version on the MIT website a bit of a chore. Here's my attempt at applying Andres Raba's wonderful SICP layout ([https://sarabander.github.io/sicp](https://sarabander.github.io/sicp)) to SICM: [https://tgvaughan.github.io/sicm](https://tgvaughan.github.io/sicm)

<comment><USER5> Thanks ... that looks great! I always preferred Sara Bander's HTML version of SICP to the PDF version that is available for free download at everyone's favorite online bookstore.

If someone is looking for the PDF format of SICM, that's available now too for the second edition.

<comment><USER6> Where would that be?

</comment></comment></comment><comment><USER7> SICM has been on my list of things to study for years, but I haven't made it much past the delightful preface:

> _When we started we expected that using this approach to formulate mechanics > would be easy. We quickly learned that many things we thought we understood > we did not in fact understand. Our requirement that our mathematical > notations be explicit and precise enough that they can be interpreted > automatically, as by a computer, is very effective in uncovering puns and > flaws in reasoning. The resulting struggle to make the mathematics precise, > yet clear and computationally effective, lasted far longer than we > anticipated. We learned a great deal about both mechanics and computation by > this process. We hope others, especially our competitors, will adopt these > methods, which enhance understanding while slowing research._

This second edition is from 2015, following the 2001 first edition.

Unfortunately, unlike SICP, it does not seem to be under a free license, so it is not legal to translate it into Spanish or produce a reformatted digital version that incorporates an actual Scheme interpreter.

<comment><USER4> The second edition is CC-BY-NC-SA. (This is indicated inside the cover of the print edition.)

[Edited to add NC.]

<comment><USER7> Oh interesting! Do you have the print edition? The copy on Library Genesis does indeed seem to contain that license, but someone could have added that when they uploaded it to libgen: [https://libgen.lc/ads.php?md5=968F60C358A99A61A2A0FD7502F476...](https://libgen.lc/ads.php?md5=968F60C358A99A61A2A0FD7502F476D8)

<comment><USER8> The Google Books copy that MIT Press links to as the "Preview" includes the CC license:

[https://mitpress.mit.edu/books/structure-and- interpretation-...](https://mitpress.mit.edu/books/structure-and- interpretation-classical-mechanics-second-edition)

[https://books.google.com/books?id=a4-pBgAAQBAJ&lpg=PP1&pg=PP...](https://books.google.com/books?id=a4-pBgAAQBAJ&lpg=PP1&pg=PP1#v=onepage&q&f=false)

<comment><USER7> So it does! Thank you very much!

</comment></comment></comment></comment></comment><comment><USER9> There's a ton to learn from this book, especially if both Scheme (or functional programming in general) and the Lagrangian and Hamiltonian formulations of mechanics are new to you as they were to me when I first came across the text online. I ended up taking the class in person and seriously enjoyed it. It was a big reason I switched my major from CS to physics, which I mean in the best way possible! I think the authors were right in their assessment that Lisps are really well suited to mathematics, and especially the type of math you see in working with Lagrangians: function composition and partial application. Plus there's the cool benefit of being able to write code that looks at other code and writes its derivative as a new program!

The two small warnings I would share with someone starting this book are

1) they introduce some of their own notation to clarify, i.e., what various derivatives mean, but this notation is different than what is found in other texts

2) it ramps up pretty quickly from solving a double pendulum to much higher- level stuff like Lie transforms and perturbation theory - it's a lot to keep in your head all at once. Don't get discouraged if you hit a wall and need to come a couple days or weeks or months later - I definitely did, and it is still fun to try to go back and make it through the harder parts. Highly recommend!

</comment><comment><USER10> Some additional interesting discussion about this book on previous HN threads:

[https://news.ycombinator.com/item?id=19765019](https://news.ycombinator.com/item?id=19765019)

[https://news.ycombinator.com/item?id=6947257](https://news.ycombinator.com/item?id=6947257)

[https://news.ycombinator.com/item?id=23153778](https://news.ycombinator.com/item?id=23153778)

[https://news.ycombinator.com/item?id=1581696](https://news.ycombinator.com/item?id=1581696)

[https://news.ycombinator.com/item?id=9560567](https://news.ycombinator.com/item?id=9560567)

</comment><comment><USER11> This book's amazing. I've only tried to understand the first few chapters so far but I found the basic idea -- reformulating the Euler-Lagrange equations in lisp, and using Spivak's alternative notation for differential calculus -- to be extremely illuminating and even inspiring when going back and trying to really make sense of (advanced) undergrad calculus.

OK, so here's my question: the scheme is great and all, but wouldn't this really benefit from a statically typed language with a rich type system? I think it would be really interesting to try to make the computations at the type level correct as well as at the runtime level. Obvious candidates I guess are Haskell/OCaml etc, or one of the theorem-proving languages (out of my depth here, but Lean/Coq etc).

I have said this before...another HN thread on SICM: [https://news.ycombinator.com/item?id=21460106](https://news.ycombinator.com/item?id=21460106)

<comment><USER12> I have been interested in doing this for a long time, and have thought about doing it in Haskell. It would be a lot of work, and some of the type decisions that would be needed would probably complicate the UX of the software (the automatic differentiation of functions of various shapes would make typing the D operator interesting; I think it would force all real-valued functions of a real variable to look like they were working in a vector space of dimension 1, or the inconsistency would be maddening). SICM's software also does a lot of "lowering" of types, so 0 (zero) is kind of a universal additive identity, but in a strongly typed system you'd need zeros of many different kinds and it might be that once all this was finished there was too much "wrapping" left visible and the scientific investigations in the SICM spirit would lose some of their charm. I guess that's a long-winded way of saying that there are lots of type puns in mathematical notation that are useful affordances even if they are slightly abusive.

<comment><USER11> Thanks that was very interesting to hear your thoughts. If you do ever decide to work on this again, I'd be interested to know and probably in helping. Others in these threads have expressed interest too. But yes, it does sound like rather a lot of work for a slightly esoteric cause. My contact details are in my profile.

</comment></comment></comment><comment><USER13> If you are more mathematically inclined, there's also "Functional Differential Geometry" by the same authors, and in the same spirit, but much shorter. The goal of the book is essentially to write the Euler-Lagrange equations in lisp, which is a breathtakingly beautiful thing.

<comment><USER14> Which is also especially beautiful, and open access as well: [https://mitpress.mit.edu/books/functional-differential- geome...](https://mitpress.mit.edu/books/functional-differential-geometry)

</comment></comment><comment><AUTHOR> I posted this because it was recommended to me several times in [0], together with several other "computational approaches to Physics" books, and thought it would be interesting to HN users. If you're looking for more books like this, the whole Twitter thread is worth a read. It's full of good recommendations.

[0] [https://twitter.com/dennybritz/status/1260137814982787073](https://twitter.com/dennybritz/status/1260137814982787073)

</comment><comment><USER15> I have a hard copy of the first edition. The dedication says: "dedicated to the principle of least action"

I have an educational resource for introduction to Hamilton's stationary action. The title is "Least action visualized".

[http://www.cleonis.nl/physics/phys256/least_action.php](http://www.cleonis.nl/physics/phys256/least_action.php)

The diagrams on the page have a slider for active exploration. Moving the slider sweeps out a range of trial trajectories. As you change the trial trajectory the diagram shows how the graphs of the energies come out accordingly.

In this resource Hamilton's stationary action is introduced in a two-stage process.

First stage: We have the Work-Energy theorem, which we can apply with equal validity in infinitisimal form. The true trajectory has the following obvious property: at every instant in time the rate of change of potential energy matches the rate of change of kinetic energy. Demanding this match as a condition we identify the true trajectory among the range of trial trajectories. That is, this initial stage is already variational approach, but it doesn't yet use the concept of action.

Second stage: Demonstration of moving in a single step from the first stage to Hamilton's stationary action.

The demonstration is for the simplest case: a uniform force, hence a linear potential. The reasoning generalizes to all cases.

</comment><comment><USER16> I did a read through last year and thought it was great. Having to actually tell a computer how to do Langrangian and Hamiltonian mechanics makes you learn it really well. Pointed out some of the interesting reasons behind why we choose or Langarangians/Hamiltonians the way we do that I didn't appreciate during undergrad.

</comment><comment><USER17> One of the good things I felt about the book, though I have read only a few chapters is that, the use the Scheme-based system, has made the notation more concrete and lucid. No vague and confusing notations like the traditional treatment.

</comment><comment><USER18> Amazingly, this book has the same author as SICP, i.e , Structure and Interpretation of Computer Programs.

<comment><USER19> One of the three SCIP authors you mean.

Not so incredible; Gerry has always loved physics and in the 80s built a digital orrery in scheme shortly after SCIP was written. I believe this book had its earliest inklings in that work.

<comment><USER20> Around March 2019, I walked up to Gerry at the end of a class he taught (I was sitting in) and he mentioned that he was actually a physics major at MIT when he was an undergrad (in addition to math) but was one course short. The course he was missing? Junior lab (now 8.13 / 8.14)</comment></comment></comment>


Self-Proclaimed Inventor of Email Files Defamation Lawsuit Against Techdirt - <AUTHOR> http://www.hollywoodreporter.com/thr-esq/proclaimed-inventor-email-files-defamation-lawsuit-techdirts-michael-masnick-961008 <comment><USER2> Oh, yeah, _that_ is sure to work. It's not like TechDirt knows anything about the first amendment or anything...

But I thought that this quote was interesting:

> Ayyadurai [the plaintiff] previously sued Gawker in a lawsuit that many > suspected was funded by Silicon Valley billionaire Peter Thiel.

The article states that there is no known connection between Thiel and this current lawsuit, but it does make you wonder. Has TechDirt done anything to anger Thiel? He's shown himself to be willing to fund someone else's suit in retaliation...</comment>


ES6 in Depth: Collections - <AUTHOR> https://hacks.mozilla.org/2015/06/es6-in-depth-collections/ <comment><USER2> This is a very well-written piece and I really enjoyed reading Jorend's analysis of "Open" vs "Close" hash table performance [1] linked in the article.

All four of these collection types are sorely needed in JS and will have many positive effects into the future. I am especially happy to have WeakSet, which virtually eliminates a number of pesky memory leak cases that happen all the time in DOM library code.

ES has a bright future and it is great to see the committee making so many great choices while it grows. It is truly great that the community has not only been given significant opportunity to comment on and contribute to the spec, but to actually test code written with the new spec using transformers like Babel to ensure that they not only sound good, they work well in practice. What a breath of fresh air it is to evolve the web this way, rather than having a committee simply unilaterally define a specification (without a reference implementation) that turns out to be bug-prone, slow, or incomplete.

1\. [https://wiki.mozilla.org/User:Jorend/Deterministic_hash_tabl...](https://wiki.mozilla.org/User:Jorend/Deterministic_hash_tables)

</comment><comment><USER3> It's too bad that JavaScript collections have ugly Java-like APIs, with get(k), set(k, v), etc.

It would be nice if the [] and . weren't essentially aliases for each other, so that [] could be use for collections. There was once a proposal for this, though it would have broken assumptions of lots of code: [http://wiki.ecmascript.org/doku.php?id=strawman:object_model...](http://wiki.ecmascript.org/doku.php?id=strawman:object_model_reformation)

<comment><USER4> Sounds like a bad idea, [] and . have always acted directly on object properties. Changing the semantics of a basic language operator can have consequences you wouldn't envision. What if an _existing_ function deals with a _new_ object?

Add a new operator, like {}.

<comment><USER5> I think using curly braces would be an automatic semicolon insertion hazard. You would at least need to introduce another "no LineTerminator here" rule.

<comment><USER4> Sure, there might be a better syntactical choice, though I'm not sure what it would be.

<comment><USER6> Use map(key). I learnt this "map as callable" idea fron clojure and wondered why it is not more common.

<comment><USER7> Yeap. I find it very elegant to be able consider maps as simply functions that _map_ elements from one domain to another: a -> b. A set can then simply be consider a special case of map: a -> Bool.

A definition like that can also make concepts like infinite sets much easier to conceive. It'd be nice to be able to express "the set of all prime numbers" or "a map between a person and their soul-mate: Peson -> Maybe(Person)" and have them be interchangeable with other Sets and Maps (of same type) on general operations like intersection, difference, etc.

But i think this interpretation is at odds with the idea of maps and sets being data structures of a given size, where you add and remove things.

</comment></comment></comment></comment></comment></comment><comment><USER8> i love how the set examples use emoji

> var desserts = new Set("🍪🍦🍧🍩"); > desserts.size 4 > desserts.add("🍪"); Set [ > "🍪", "🍦", "🍧", "🍩" ] > desserts.size 4</comment>


Bandwidth.com – EdgeMarc Device Passwords Potentially Compromised - <AUTHOR>

Just got this email, eeek!
--- Dear Bandwidth Customers,
Bandwidth has discovered an issue wherein EdgeMarc device default passwords may have been compromised on the internet.
Any customer who currently owns the EdgeMarc box should immediately change their password.
If you are unsure if your specific device has been compromised, you can take the following steps to investigate.  However, it is still highly recommended to change the password:
In the EdgeMarc GUI, under 'System' click on "Client List".  If there are any entries listed other than known and local IP addresses, there is a strong possibility that your device has been compromised.  To resolve, remove the offending IP address.
Additionally, the following steps should be taken to to ensure a secure device:
Disable PPTP (Point-to-Point Protocol) - Under PPTP server > Username, ensure there is no user built unless it is a known user.
Disallow WAN clients - Under VoIP ALG, uncheck both the 'allow clients on WAN' option, as well as the 'Enable LLDP' option.
Verify no additional scripting has taken place, by looking under 'User Commands'.  Specifically, if the following script is present, it will need to be deleted:

  ln -sf /etc /etc/images/m.txt
  chmod 777 /etc/images/m.txt/config/passwd
  sed -i -e s'_'"501"'_'"0"'_' /etc/images/m.txt/config/passwd
  sed -i -e s'_'"501"'_'"0"'_' /etc/images/m.txt/config/passwd
  sed -i -e s'_'"/etc/images"'_'"/"'_' /etc/images/m.txt/config/passwd
 --- <comment><USER2> Seems the default root password is 'default' or 'password', and is listed in their manuals / documentation.

[https://www.google.com/#q=edgemarc+default+password](https://www.google.com/#q=edgemarc+default+password)</comment>


War on talent - <AUTHOR> http://www.ft.com/intl/cms/s/0/c53a9282-735e-11e5-bdb1-e6e4767162cc.html <comment><USER2> Can't seem to read it, there's a paywall.

<comment><USER3> Google [war on talent financial times], it'll show up.

TBH I didn't think it was worth reading; just someone complaining about how "talent" becomes meaningless as a word when it's applied to Walmart stockers.</comment></comment>


Things I Did Wrong with My Last Startup - <AUTHOR> http://hippoland.tumblr.com/post/43995877479/3-things-i-did-wrong-with-my-last-startup

<comment><USER2> Why not founding it again? A crutial point of a startup success is timing. Maybe this is a case of founder's timing. Founders all the time decide to pivot or persevere. And sometimes, to quit. Why it has to be a permanent quit? Three years and a good amount of experience laters, the founder can make it happen! I think we may face a failed startup as something you shut down, that is not demanding any more of your time and money. But not something you must never again touch. Not dead, but hibernating.

<comment><AUTHOR> Soneca, you are absolutely right. In this case, we shut it down, and my co- founder decided to move on. This just wasn't meant to be. After that, I decided to team up with a different friend of mine, and we are working on LaunchBit. So, while that was the end for Parrotview, it's not the end of my startup journey. :)

<comment><USER2> Congrats, hippo! I should have guessed though, no one shares tough insights of self-awareness, unless he already have overcame it. :)

</comment></comment></comment><comment><USER3> I don't know if there was much you could do with a product like that. I don't know who that would appeal to. Was it basically Google Hangouts for shopping?

<comment><USER4> Sounds like an excellent idea to me ;-)

Walk around a mall. Watch the number of people using their phones to take photos, talk to their friends about options, phoning home to check they're getting the right thing, etc.

<comment><USER5> They're all young teenagers. Is that a great revenue model?

<comment><USER4> I dunno. Depends on whether you can do interesting things with 'em.

For example - you build the social hot-or-not for clothes purchases. How much is the data from that worth to a high-street retailer as a way to guide their pricing and stocking decisions.

(and - come to that - I see folk well out of their teen years doing this. Women especially in clothing stores... and what is the purchasing power of groups who are rich enough to afford smart phones in the first place)

</comment></comment></comment></comment><comment><USER6> My hearty thanks to the author for being so frank about this.

<comment><USER7> +1 Some good info here. Thanks for posting! Things everyone puts off, but really make a difference.

</comment></comment><comment><USER8> Great advice. Thanks for sharing. I'm working on my own project and know that the failures you note are universal. It's helpful to hear them again and use it to channel my efforts on building an audience especially when development is slow.

</comment><comment><USER9> It seems to me the main reason for this failed startup is lack of marketing. I am in the middle of building/promoting a startup company and the first batch of customer seems very quite difficult to attract.

</comment><comment><USER10> I am wondering here what more can be done about researching/developing that revene model. Anyone have links, thoughts, whatever?

Thanks for sharing this.</comment>