Folding Promises in JavaScript - <AUTHOR> https://www.codementor.io/vladimirgorej/folding-promises-in-javascript-b1l7mwh93 <comment><USER2> >How can we make it better ? Let's start by removing the requirement for identity value to always be the promise.

I challenge the view that making the identity value being able to be something other than a Promise is 'making it better'. Pointless abstraction is one of my pet peeves in this industry. This looks like it has gone from a fairly straightforward, if kludgy, piece of code to something far more complex. Why not just:

      const listOfPromises = [...]

      const result = Promise.all(listOfPromises).then(results => {
        return results.reduce((acc, next) => acc + next)
      })

    ?

<comment><USER3> Same reason given in the bluebird library documentation:

> Promise.reduce will start calling the reducer as soon as possible, this is > why you might want to use it over Promise.all (which awaits for the entire > array before you can call Array#reduce on it).

Whether this is ever necessary is another matter :)

<comment><USER4>
        let accumulator = 0
        for (let item of array) {
          const value = await item
          // your code here
        }

Is identical, doesn't use 'cool' reduce features but is much easier to read in my opinion.

<comment><USER5> Wouldn't this code only execute 1 promise at a time? I thought Promise.all allowed promises to be resolved in parallel

<comment><USER6> Indeed. You most likely should do `await Promise.all` and then do the reduction.

</comment></comment></comment></comment></comment><comment><USER7> I don't think this is very well written. It doesn't start with any motivating problem, it introduces terms (functor) without defining them, and a lot of what is discussed doesn't apply to solving the problem.

</comment><comment><USER8> > Folding Promises in JavaScript

Or: How to make simple things complex and make a codebase a complete puzzle for those that come after you?

<comment><USER9> I feel nothing has improved code readability like the recent mainstreaming of map/filter/fold/reduce and "const all the things". This type of code is so easy to follow, reason about and trivial to debug at every step, once you internalize the few primitive functions.

I don't think you need to necessarily memorize these transformation names, but writing these types of functions is all I seem to be doing these days, transforming one thing into another line for line.

<comment><USER10> I feel the code I wrote while on this bandwagon is the hardest to understand for others and for me myself today.

        pullAllBy(pluck(things, 'bar').map(compose(xor, lol, rofl)).reduce(differenceWith('id'))

Just write your transformations inline and go work on the next feature.

<comment><USER11> I feel like the functional code you wrote was written to intentionally obfuscate what is being done. For instance, composing a bunch of methods inline doesn't have any utility for it unless you define what compose(xor, lol, rofl) really means.

Ideally this is how it should be written for maximum readability.

      things
      |> pluck('bar')
      |> map(xor)
      |> map(lol)
      |> map(rofl)
      |> reduce(differenceWith('id')

The code is written equally well without using pipe operator but the proposal to introduce it is in works [1].

Here is it using lodash (not even lodash-fp), and this is going to do a single for loop when executing because this is lazy.

      _.chain(things)
       .pluck('bar')
       .map(_.xor)
       .map(_.lol)
       .map(_.rofl)
       .reduce(_.differenceWith('id'))
       .value();

It's no less readable than the code you'd write using using unfolded transformations.

1\. [https://github.com/tc39/proposal-pipeline- operator](https://github.com/tc39/proposal-pipeline-operator)

<comment><USER12> I agree, but you shouldn't map 3 times when you can map once over the data.

       things
        |> pluck('bar')
        |> map(compose(rofl, lol, xor))
        |> reduce(differenceWith('id')

<comment><USER11> I made my case against the compose in the post.

Composing xor, rofl, lol isn't any better (esp in terms of readability) than it is individual maps.

What would be better is this:

      const makeHilarious = compose(rofl, lol, xor);

      things
        |> pluck('bar')
        |> map(makeHilarious)
        |> reduce(differenceWith('id')

<comment><USER10> This means that to change this code you first have to look for the makeHilarious definition, then the definitions of rofl, lol and xor, then figure out what they all do separately and together, and if you can change them without breaking anything else in your application.

        things
          .map(thing => x.bar)
          .map(thing => {
            // whatever happens in rofl
            // whatever happens in lol
          })
          .reduce((acc, thing) => {
            // more stuff
          }, {})

This is code that is easy to understand and safe to change. The maps could be combined into one function body if it's convenient.

<comment><USER11> I anticipated that makeHilarious is more than once used method, even if it is not, once you look at it's definition, you understand the intent behind "xor -> rofl -> lol".

It is one thing to quickly be able to understand that the person is doing a xor, then a rofl and then a lol of each element of an array, and a whole another thing to understand what the combination of these three actions over an array means. The python school of "code is read more than it's written" heavily stresses on explaining how easily the code should be understandable the first time someone reads it, but not whether it's easy to reason about or not.

The beauty of declarative style programming isn't to get more readable code immediately, but rather that once you understand the vocabulary, how easy it is for you to understand and reason about the code.

For instance, imagine reading a novel which is written like this:

"After Jack was done from the place where he went to do things for money everyday, he entered an establishment which served drinks that get you inebriated for money. This establishment was one he frequented regularly and preferred it over the others. He asked the man behind the counter for a wheat fermented brewed drink. After putting the drink to his lips and pouring it in to his mouth, he felt a sense of calmness enter his mind. It pushed all the thoughts which occupied his mind away, as he earlier desired before entering this establishment."

As opposed to:

"Jack really needed a drink after hard day at work. He went to his favorite pub, and ordered his favorite beer. After finishing the pint, he finally felt relaxed."

The Python philosophy (which is permeated everywhere in imperative world) is to describe everything in the simplest possible terms just in case there are people who may not understand what work, pub, beer, bartender, and relaxed means. But this just prevents from understanding of the actual purpose of the code.

This is at least the basic philosophy behind not using for loops everywhere.

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER13> I can't quite understand the difference between endomorphism ("input and output of the transformer must be from the same category") and homomorphism ("structure preserving transformation. We always stay in the same category"). Can someone help?

<comment><USER14> I believe homomorphism is a subset of endomorphism.

So a function that turns an array into another array of different length would be endomorphic (since it maintains the same type), but not homomorphic since it has a different structure (a different set of keys).

<comment><USER15> The other way around. A homomorphism is a structure-preserving map between two arbitrary objects, whereas an endomorphism is a homomorphism where the source and target objects coincide.

</comment></comment></comment><comment><USER16> With async/await this can become:

        const reduceP = async (fn, identity, listP) => {
          const values = await Promise.all(listP)
          return values.reduce(fn, identity)
        }

The whole thing feels like a synthetic and overcomplicated example, though. In practice I'm sure I'd just write:

        let total = 0
        while (listP.length > 0) {
          total += await listP.pop()
        }

<comment><USER3> That code does the same thing as [https://news.ycombinator.com/item?id=15302465](https://news.ycombinator.com/item?id=15302465) but not the same thing as the code in the article.

</comment></comment><comment><USER17> I don't know much about these concepts but isn't `const objToArray = ({ a }) => [a];` losing data, that being the key of the value in the object? I'm asking because it says that "Isomorphism is a pair of transformations between two categories with no data loss".

In any case, this is very helpful, thanks for writing/sharing.

<comment><USER18> It's a pair of transformations between [A] and { a: A }, not between arbitrary arrays and objects.

As long as you know what the transformation is, you can convert between them without data loss.

</comment></comment><comment><USER19> "Programs must be written for people to read, and only incidentally for machines to execute." \- Harold Abelson

</comment><comment><USER20> The author mentions the library Bluebird, which I think is a fantastic library. The 'mapSeries' method it offers is also very useful when iterating over an array of values that need to be 'promisified' and mapped in the given order. You can even set 'concurrency' as an option, which puts a limit on the concurrent promises that can run (great for reducing API load).

</comment><comment><USER21> I've written a javascript library to deal with folding and mapping recurring promises (i.e. promises that resolve to a value part of which contains clue to the "next" promise)

[https://github.com/google/chained-promise](https://github.com/google/chained- promise)

</comment><comment><USER22> With async (it's just monads!):

      listOfPromises.reduce(
        async (m, n) => await m + await n,
        0,
      )</comment>


JsFiddle: a REPL for web development - <AUTHOR> http://jsfiddle.net/

<comment><USER2> Yep, JsFiddle is brilliant.

There are a few others too.

<http://jsbin.com> \- Not as many features as JsFiddle and the preview is on a separate page. The HTML/CSS/JS isn't kept completely apart either.

<http://cssdesk.com> \- Primarily for CSS/HTML. Preview is automatically updated.

<http://mootools.net/shell/> \- Similar but more Mootools-centric; fewer features etc than JsFiddle.

<comment><USER3> You can see your results on their own page by appending /show to a saved fiddle, see:

<http://jsfiddle.net/amadeus/5y5nE/show/>

Also, it's recommended to use jsFiddle over Mootools Shell, since MooShell is essentially a really old version of jsFiddle, and will eventually be removed from mootools.net

<comment><USER2> I was aware that you can see the results on their own page. What I meant was that not having to switch between views is one of jsfiddle's strengths over jsbin. Edited my earlier reply to remove the misleading 'but'.

Thanks for the info about MooShell. I don't use it but wasn't aware it was to be killed off.

</comment></comment></comment><comment><USER4> It really is great for fiddling with html,css,and javascript all on the same screen without having to deal with a complicated development environment or separate files.

It would be a nice platform for teaching basics, or even introducing something new.

<comment><USER5> Some Stackoverflow members use it to paste solution and prove that it works :)

</comment></comment><comment><USER6> How amazingly cool is this!

<http://jsfiddle.net/michaelsbradleyjr/sZUtU/>

I had not really tinkered with flapjax on the client-side until tonight, but jsfiddle sparked my instincts to really fiddle with something I had been delaying fiddling (or "tinkering") with.

So, thank you, jsfiddle! I think you're going to make for a powerful creativity enhancer. :-D

</comment><comment><USER7> Would be nice to have a preloaded example - i had to look at the screen for half a minute just to sort out all the elements that don't make immediate sense if there's not context that you're accustomed to..

<comment><USER8> Here you go: <http://jsfiddle.net/derek/Vjxt2/>

<comment><USER9> Cool! Showing a twitter feed using YQL is a great example. Is there a gallery somewhere of cool javascript widgets?

</comment></comment></comment><comment><USER10> Very nice. There was a different tool I used for prototyping html, but it wasn't as nice and intuitive as this. For now it's bookmarked so I can look at it in more depth later.

</comment><comment><USER11> I think Panic should update Coda to allow a similar 4-square split of the window. Currently you can split the window as many times as you want, but they all have to be the same orientation (ie. You could have 4 rows _or_ 4 columns.

But yes jsfiddle is great. Note that you can load more resources into it, like KnockoutJS, and use them to. It also does automatic version control (well, the version number increments when you press save, but the old URL still works). I first discovered it in the Stackoverflow JS chartroom, where everyone was using it. I showed a lecturer at university, and now lots of people there are 'fiddling.'

</comment><comment><USER12> I recently wrote a little throwaway blogpost that used the embed ability of jsFiddle ([http://breakfastdinnertea.co.uk/blog/keep-those-rows-line- li...](http://breakfastdinnertea.co.uk/blog/keep-those-rows-line-little- jquery-snippet/) \- excuse the pig ugly design et al). I found it an absolute joy to work with. It also provides nice fork abilities for any ensuing discussion / counter arguments on Twitter or wherever.

</comment><comment><USER13> JSFiddle is great for embedding code examples in a library's docs too. Highcharts uses them in the API reference, and it's outstandingly useful.

</comment><comment><USER14> jsfiddle is really good. I like the auto indenting feature it is doing pretty well. One small feature request :) it would be better if it shows error some box or some thing. So it would be easy to quickly rectify instead of going through the syntax check somewhere else.

</comment><comment><USER15> nice! .. one weird UI effect though - when you mouse-over one of the three HTML/CSS/Javascript boxes, the box label disappears!

<comment><USER16> on the contrary, surely a feature.

</comment></comment><comment><USER17> A wonderful project written in MooTools- IMHO, a civilized and superior JS toolkit if your JS environment is homogenous/sane.

<comment><USER16> surely the stability of your architecture is not dependent on the library you use?

unless of course your library defines your architecture- but i wouldn't consider a library of that nature a "toolkit".

<comment><USER13> It is, to some degree. For one, you buy into certain module management systems when you choose a library like jQuery, Dojo, MooTools. Another example: you buy into unique implementations of promises which are used throughout the library. If you used jQuery before 1.5, you didn't even have them and had to use callbacks -- that definitely impacts your architecture.

</comment></comment></comment><comment><USER18> MDC, use this!

<comment><USER19> The developer, Piotr Zalewa, currently works at Mozilla.</comment></comment>


YouTube TV - <AUTHOR> https://youtube.googleblog.com/2017/02/finally-live-tv-made-for-you.html <comment><USER2> This looks too expensive for what it offers. Doesn't Hulu cost a small fraction of this? You get shows slightly delayed, but you also get coverage from a bunch of cable networks.

<comment><USER3> Hulu is what, 15 a month? So you'd be paying ~20 more per month in order to get access to shows as they come and (most importantly) live sports? It's a bad value if you don't watch sports, but $35 seems pretty reasonable if you do.

<comment><USER2> Sports! That makes more sense.

</comment></comment></comment><comment><USER4> From TV to internet to TV on internet to internet TV on any devices. One thing I wonder about is how people who purchase "bundles" traditionally will react. I'd imagine they are the biggest consumer of TV programs. (TV + INTERNET or TV + Phone + Internet style bundles). Will it end up costing the same when you break you bundle to only get internet from a provider and get "TV" from Youtube?

Another question I have is about the "cloud DVR". How does it work? Is the content already in a server somewhere so when I hit the "DVR" it just tags that? It makes no sense saving the same content multiple time because multiple people tried to DVR the same episode right?

Is lot of the modern TV already through internet? If not, won't this cause an increase in internet bandwidth used? Maybe it's no significant but i'm curious about it none the less.

There was a talk on HN about cell phones and FM being enabled on it. Will a similar thing happen on TV, i.e my TV won't work without internet in the future?

Does privacy concerns increase with this? Is it easier to track users view patterns and what not with this as opposed to traditional tv? Will it be more likely that people will post the episodes or clips they watch to youtube or will it be less common as it will be even easier for youtube to recognize and flag stuff? (I wonder if youtube will provide a tool to post tiny clips directly from TV so people can have discussions and what not as well). Thanks in advance if anyone takes time to answer any of my question!

</comment><comment><USER5> If you're somewhere between a casual and a die hard sports fan, the $35/month price tag is rather competitive for the sports alone. Alas, seems to be US only for now. :o(

</comment><comment><USER6> > In total, YouTube TV gives you access to more than 40 networks

Not bad for $35/month. I do wonder how much the add-on networks like Showtime would cost.

</comment><comment><USER7> This is decent for sports lovers. I might end up going with this once my current comcast promotional plan expires.

</comment><comment><USER8> $35 is kind of steep.

</comment><comment><USER9> No difference compare to ps vue?</comment>


We Have a Bad News Problem, Not a Fake News Problem - <AUTHOR> http://www.snopes.com/2016/11/17/we-have-a-bad-news-problem-not-a-fake-news-problem/ <comment><USER2> Part of it is an audience problem.

We have good news, e.g. [http://hosted.ap.org](http://hosted.ap.org)

The problem is nobody will read it. It's not sensationalized and dramatized enough. It's not edited into a series of one second video clips with an ominous soundtrack, with an occasional clip of guys in black marching with ak-47s because isis. It requires an attention span longer than 30 seconds.

<comment><USER3> Then it's a failure of the website in their inability to deliver the message in a format acceptable to the audience. "people are stupid" is a ridiculous cop-out for their inability to understand basic human psychology. People are not stupid, this site is competing with literally thousands of websites doing the same thing. I have no words for sheer arrogance of calling people stupid when they don't read this shitty website, we get our daily moral chiding from nytimes, we don't need more of that.

<comment><USER4> I don't get the impression the parent comment is saying "people are stupid". I think the point is "news != entertainment". At least it shouldn't be. If you want to be entertained go watch a movie. If you want to be informed well on a topic then read or watch the "boring" news.

If the incentive structure props up the "news == entertainment" organizations better than the "news == boring facts" organizations we have failed and will ultimately pay the price.

</comment></comment></comment><comment><USER5> The two do tend to blur together a bit through the actual news regurgitating fake news, though. This isn't a new thing either - the Emma Watson 4chan story a couple of years ago was a good example. That was seeded by a typical fake news website that had tried similar tricks before, and as soon as the first real news site failed to check the source was real and leapt on it everyone else followed suit.

<comment><USER6> the entire newscycle is complicit. if trump tweets something, 500 news agencies write a variant of a story around the tweet.

the majority of news agencies dont seem to have the self discipline to NOT cover a story the others are, out of fear of lost eyeballs. news agencies could be even more powerful if they stopped amplifying bullshit, and were selective over what deserved attention. instead every company covers every viral event, creating a feedback loop of displacement. noise noise noise.

</comment></comment><comment><USER7> Article described a few instances of fake news but failed to give an example of bad news. After reading it twice it's not clear if "bad" means "negative" or "of poor quality."

<comment><USER8> \- The sciennce articles that come to conclusions the original study didn't, there have literally been hundreds of them in the UK press over the past 10-15 years. The MMR scare is a prime example of bad news (its actually 99% fake but with that nugget of truth in the middle that is distorted so much its fake news).

\- All the bad tech news like all the magical batteries that are coming out next year, and haven't actually every come out at all.

\- The political news where they attack someone for something they didn't do.

\- The news papers hacking into politicians/famous peoples computers to steal private information and publishing stories on it.

\- The pieces about a person that are purely ad hominen and have little to nothing to do with the job they do.

\- The pieces that endanger people doing dangerous jobs around the globe, especially things like famous people working in Afghanistan and necessitating them to quit their jobs.

\- The news that is just "he said" which has even become twitter quotes now. Just presenting that with no actual points, history or anything else to actually make an article.

\- Taking quotes from speeches that are the exact opposite of what the person meant, just plain taken out of context.

That right there is 80% of the news we read every single day on news papers around the world. I could go on and on about all the fake/bad news types we see but my conclusion having personally fact checked a lot of news that could be verified is that 95% of it is either a lie or intentionally misleading. Its every news paper I have checked in the UK and the USA. Its scary how bad the news is.

</comment></comment><comment><USER9> > Even worse, the term "fake news" is now being so broadly applied as to refer > to news outlets that evince a political slant (or, currently, those > perceived as having "helped Donald Trump get elected").

> Those on the more liberal end of the political spectrum might decry Fox News > Channel programming or the National Review's reporting as "biased" and > unreliable, just as those on the more conservative end of the spectrum might > similarly dismiss MSNBC's programming or The Nation's reporting. But we > would be entering perilous territory if we started tagging every news source > with a strong partisan political viewpoint as "fake news."

This is the problem. And the Corporate media has swooped in to fan the flames of people who are caught up in the emotions of the election. They think this might win them back some credibility in the eyes of the public or cement there position as the respectable 'real news'. Its deeply disturbing whats going on. The Corporate media and some over zealous activists are attacking the Press itself. Its simply a call for blanket censorship of the press based on some arbitrary designation such as 'fake news'.

<comment><USER10> It's probably time to go back and rewatch Noam Chomsky's video "The Myth of the Liberal Media". I believe it was from 10 years or so ago. His premise is there is no liberal (or even conservative) media, just a large corporate media.

<comment><USER9> Yes, and also "Manufacturing Consent"

[https://en.wikipedia.org/wiki/Manufacturing_Consent](https://en.wikipedia.org/wiki/Manufacturing_Consent)

The corporate media will do everything they can to maintain the status quo including attacking the alternative media as 'fake news'.

</comment></comment></comment><comment><USER11> Corporate media was pushing one candidate heavily, it didn't get elected, now they are pushing story that people somehow read fake news, on Facebook! :), implying that people are not good or smart enough (unlike them). That condescending attitude got us where we are.

Problems are not as simple. There is not nearly enough good reporting, analysis. War is promoted heavily. TechNews are last few years plagued by what I call 'sponsorship reporting'. Apple always get glowing reviews no matter what. What I believe is most troubling, is that even people who participate in this started to believe in this news.

Anyhow, good news is that we are talking about it and push for change is present. We need a lot more respect for other people views before anything can happen. This is most lacking now.

</comment><comment><USER12> After getting a reference to a Peanuts cartoon, that turned out to not be a Peanuts cartoon but something from ImageBlitz (now defunct) that was also supported by white power nationalists on Stormfront, I am thoroughly vetting everything.

Get a picture > check Snopes > put photo through a photo forensic application > report back to the sender and everybody they sent the image to.

When I'm accused of being left wing because of this due diligence, I make sure my accusers know that I am an equal opportunity debunker. Find me a liberal left leaning image and I'll try to debunk that.

</comment><comment><USER13> Wasn't it Norm Macdonald who invented "fake news"?

<comment><USER14> That news is now more truthful than the real news.

</comment></comment><comment><USER15> The problem is that we have no real journalism anymore. Most journalists now are keyboard warriors that just take hearsay and rumors they heard on Twitter and create a story out of it. If they don't do it, someone else will and it takes too much time to actually investigate it properly.

With the viral nature of social media, false stories become fact really quickly.

I feel like Stephen Glass (the journalist that faked all of those news stories in the 90s while working for the New Republic) wouldn't even get fired if it happened now.

I'm all for the freedom of the press, but there needs to be consequences for completely false stories that could actually hurt someone's livelihood.

</comment><comment><USER3> when did snopes turn into some kind of political fact-checking website ? Isn't snopes literally two guys running this site from their bedroom? Not biased at all.

[http://dailycaller.com/2016/07/28/snopes-caught-lying- about-...](http://dailycaller.com/2016/07/28/snopes-caught-lying-about-lack- of-american-flags-at-democratic-convention/)

<comment><USER16> _when did snopes turn into some kind of political fact-checking website?_

At least since they hired this self-admitted biased person to do political "fact checking": [http://dailycaller.com/2016/06/17/fact-checking-snopes- websi...](http://dailycaller.com/2016/06/17/fact-checking-snopes-websites- political-fact-checker-is-just-a-failed-liberal-blogger/) although she isn't the credited author of the item the Daily Caller calls out.

<comment><USER3> But, The owner of Snopes is a registered independent. This basically guarantees that Snopes is unbiased truth.</comment></comment></comment>


Drone Developers Consider Obstacles That Cannot Be Flown Around - <AUTHOR> http://www.nytimes.com/2014/09/01/technology/as-drone-technology-advances-practical-obstacles-remain.html <comment><USER2> _" Drone technology has not been thoroughly tested in populated areas"_ \- Except by tens of thousands of hobbyists over many decades, with apparently nobody in the press really noticing until recently when cameras got added to the RC loop, which surely makes it less risky as it is much easier to fly, so I am sure it can't be that bad.

 _" and commercial use of drones is not allowed in the United States."_ \- Although the only legal ruling so far for the first person taken to court by the FAA says that commercial drones are completely legal and that the FAA is talking crap. FAA has asked for an appeal and the NTSB has kicked it into the long grass since March. - [http://blogs.findlaw.com/decided/2014/03/faas- commercial-dro...](http://blogs.findlaw.com/decided/2014/03/faas-commercial- drone-ban-shot-down-by-admin-law-judge.html)

This is really shitty journalism.

<comment><USER3> I have read a few cases of drones killing people so it's not exactly unnoticed. The difference is their calling it a model aircraft or Toy vs drone.

EX: [http://www.dailymail.co.uk/news/article-177139/Teenager- kill...](http://www.dailymail.co.uk/news/article-177139/Teenager-killed-hit- model-plane.html)

[http://nypost.com/2013/09/05/man-decapitated-by-remote- contr...](http://nypost.com/2013/09/05/man-decapitated-by-remote-controlled- toy-helicopter/)

</comment></comment><comment><USER4> What is the proposed usage for these drones if I may ask? I don't want to be a pessimist but if these drones are supposed to be transporting anything of value wouldn't that encourage shooting these things out of the sky?

<comment><USER5> Considering these drones have GPS and Celular connectivity built-in, shooting them down would not be a very good idea, since the owners would quickly take notice. The built-in video camera can also be used to record and transmit images of the robber.

I can see this being used for items with value high enough to justify the drone delivery costs (say, > $20) but not too high to the point where having a drone deliver it would be too risky.

The exact values are certainly being worked out by actuarial scientists. There will be some sort of insurance involved, inside the delivery cost.

Even if the urban delivery application doesn't materialize in the near future, I see this being very useful in a rural setting. Or to deliver emergency supplies to hard to reach locations.

<comment><USER6> What if mischief makers start shooting them down just for the thrills ? Since drones are unmanned there is no equivalent situation we can compare it to.

<comment><USER7> Of course it can be done, but I think you fail to realize that something the size of a dinner plate travelling upwards of 50mph in the sky is going to be a whole hell of a lot harder to shoot than say a clay pigeon. I say this as someone who built and flies a quad-rotor UAV (look up the QAV400 frame for an idea) and used to fly the Shadow 200 in the military (with 480 combat flight hours over Iraq).

I'm not saying you can't shoot these things down, but people that think it will be easy have a lot to learn about this technology. Also, when people shoot up in the air, there are often unintended victims when the bullets come down.</comment></comment></comment></comment>


Google Buzz -- and you thought Facebook had privacy issues? - <AUTHOR> http://blogs.computerworld.com/15559/google_buzz_and_you_thought_firefox_had_privacy_issues

<comment><USER2> I made a "hello world" sort of buzz post as soon as I got it a few days ago. Last night I looked at my public google profile ([http://www.google.com/profiles/<username>](http://www.google.com/profiles/<username>)) and was shocked to see that my buzz post was shown on there. Yes, I allowed that first post to be "public", but its not immediately clear how public that actually is. I had assumed that it meant public to all of my buzz followers but apparently it meant public to the entire world.

<comment><USER3> The meaning of public on any social network nowadays pretty much always means public to the entire world.

</comment></comment><comment><USER4> So the author opts-in to share her location information, then complains that Google is compromising her privacy when Buzz uses that information?

<comment><USER5> Not only did the author opt-in, there's also a way to opt-out. There's a big X next to the location on the compose form. Clicking the X removes the location.

</comment></comment><comment><USER6> I'm still waiting to get Buzz enabled so I'm not sure on this, but is there an option for per 'buzz' use of location data? I could see good use for the odd occasion of "meet me here" message with the data added. Even better if it knew the recipients location and they could be provided with a route on how to get there!

</comment><comment><USER7> The url itself is quite odd (firefox instead of facebook).</comment>


Chernobyl: Title Typography and Design Thread - <AUTHOR> https://www.reddit.com/r/graphic_design/comments/burcqg/absolutely_love_the_font_choice_for_the_chernobyl/ <comment><USER2> Saw it as well as I follow the subreddit. Not sure whether people here will like it but I did — definitely it's about the little things since designers geek over these small details.

Nonetheless I loved the typography as well (and the show)

</comment><comment><AUTHOR> TL;DR specifically about the font:

> essentially they created a font, as far as I understand. And the font was > kind of inspired by Cyrillic fonts. And there's a number of Cyrillic fonts > that came out of the Soviet Union. The Soviet Union had their own state-run > typography department and they did create a number of fonts, including > something called – well, it's referred to as Poor Man's Futura. There's a > bunch of them. Anyway, the point is rather than font out and dork out, what > we went for was that. Essentially an English font that conveyed the truth of > what Soviet fonts looked like at the time.

They've got weird kerning. Some of the numbers are slightly bizarre for us. And then we messed around with the color a little bit and we fuzzed some of the edges just to make it feel like it was part of 1986.

[https://www.reddit.com/r/graphic_design/comments/burcqg/abso...](https://www.reddit.com/r/graphic_design/comments/burcqg/absolutely_love_the_font_choice_for_the_chernobyl/epk8pe5/)

segment from the podcast is at 55m 37s:

[http://scriptnotes.net/401-you-got-verve](http://scriptnotes.net/401-you-got- verve)</comment>


I might be an arsehole, but at least I'm not wrong - <AUTHOR> http://blog.samuellevy.com/post/26-i-might-be-an-arsehole-but-at-least-im-not-wrong.html

<comment><USER2> I still do this all the time. It's a hard habit to break, and it seems to spread from one knowledge center outwards. I've gotten so used to knowing the answers to tech problems for people that it ripples out to things I've only skimmed. I catch myself once in a while, but you really need someone smacking you every time you do it to break the habit.

<comment><AUTHOR> My fiancé is the one who beat it out of me. It still happens sometimes, but being aware of it really helps.</comment></comment>


Bitcoin Mining Now Consuming More Electricity Than Many Countries - <AUTHOR> https://powercompare.co.uk/bitcoin/ <comment><USER2> I've conducted the most detailed and precise energy estimate of Bitcoin miners and bounded it to 5.61-10.93 TWh/year as of 28 Jul 2017: [http://blog.zorinaq.com/bitcoin-electricity- consumption/](http://blog.zorinaq.com/bitcoin-electricity-consumption/) Today it's probably closer to ~15 TWh/year which represents ~0.01% of the world's energy consumption.

However this article claims 29.05 TWh/year, basing it on Digiconomist which is the work of an _amateur_ and known to overestimate by ~2×: [http://blog.zorinaq.com/serious-faults-in- beci/](http://blog.zorinaq.com/serious-faults-in-beci/)

<comment><USER3> Why are you and the article using TWh/year? Why not just use watts? By my math...

      15 TWh/year
      = 15000 GWh/year
      = 41 GWh/day
      = 1.7 Gwh/hour
      = 1.7 GW

Which is approximately one of these: [https://en.wikipedia.org/wiki/File:Grand_coulee_dam_aerial_2...](https://en.wikipedia.org/wiki/File:Grand_coulee_dam_aerial_2.jpg)

<comment><USER4> Or put another way, approximately enough to power 110 of the most powerful supercomputers in the world, the Sunway TaihuLight, that would give a combined performance of 10 exaFLOPS.

[https://www.top500.org/list/2017/11/?page=1](https://www.top500.org/list/2017/11/?page=1)

Given bitcoin's current throughput that's about 1 exaFLOP equivalent per bitcoin transaction.

There is no wealth being created here, merely a lot of wealth being rapidly redistributed with a great proportion of that literally turned into heat.

This will not end well.

<comment><USER5> Although I'm a bit of a biased (dumped btc) hypocrite (made good money from it), bitcoin kinda needs to die. There are vastly superior alternatives that improve on btc in pretty much every way. Bitcoin has got the name though, so people keep buying it.

</comment></comment></comment></comment><comment><USER6> I totally agree that this is insane - but it is not much more insane than what we do with gold, we dig it from the ground and then put it back to sit in underground vaults. Still I guess gold is much more reliable as a store of value:)

[https://medium.com/@zby/proof-of- work-8d8265def194](https://medium.com/@zby/proof-of-work-8d8265def194)

By the way it is important to note that with each block halving in a simplified model (ignoring fees) should reduce the hash power by half.

Proof of Stake might help us here: [https://medium.com/@zby/proof-of-stake- can-be-cheaper-than-p...](https://medium.com/@zby/proof-of-stake-can-be- cheaper-than-proof-of-work-da14223a965) \- but it is not entirely clear that there are no holes in the PoS systems design.

<comment><USER7> Or fracking that makes us drink contaminated water.

But the HN community wants something like "Proof of planting a tree" or something like that...

Take a look at "Proof of Space" and "Proof of Time" by [https://chia.network/](https://chia.network/)

<comment><USER8> Can you link to anyone at all on Hacker News claiming that cryptocurrencies should be based on proof of planting a tree, or were you making a strawman argument?

<comment><USER9> There were a few green proof-of-delivering-marijuana start-ups, but I can't remember any green proof-of-planting-a-tree ones.

</comment></comment></comment></comment><comment><USER10> I've always touted the line about comparing the energy consumed to the value produced. And while I still think that you must normalize the numbers, I also start to grow concerned that its continued growth seems like it might actually be a problem.

Oh, wow, -- lightbulb -- I didn't notice this until I started to write this post. I was going to ruminate about what PoW could we possibly do instead (presuming we need PoW for a good cryptocoin).

Now I'm thinking that _this_ is the correction that will finally level off speculation?

Bitcoin's value is bounded: it can't be worth much more to humanity than the sum of all global financial services (likely worth much less). But its energy consumption is only bounded by the perception of its future value. Hash rate growth is fueled by speculation in continued growth in the bitcoin exchange rate.

At some point the energy consumption may grow fast enough to damper excitement about future gains. Then again, with each halving the inflation rate slows. So it's calibrated to keep increasing.

I wonder if the next Bitcoin community crisis will be different approaches to difficulty or reward. Those seem much more "untouchable" than block size, so hopefully not.

<comment><USER11> > But its energy consumption is only bounded by the perception of its future > value. Hash rate growth is fueled by speculation in continued growth in the > bitcoin exchange rate.

How do you figure? Miners mine bitcoins and sell them at the current exchange rate -- not a future one.

Mining to speculate on future price increases make no sense. If you believe the price will rise, just buy bitcoins now (no reason to mine them at a loss).

<comment><USER12> Are miners actually selling all earned bitcoins immediately? If so, that means there must be at least 20 million USD "entering" Bitcoin every day in net terms. That seems like a lot, certainly much more than could be supported by actual economic activities in Bitcoin (including illegal ones).

How many people are there who are willing to use, say, 10k USD of their own money for gambling? How many greater fools?

Then again, some of those "greater fools" could be people holding Bitcoin that they collected from ICOs, so who knows.

As they say, the really tricky part of attempting to profit from the bursting of bubbles is the timing.

<comment><USER13> 20M USD/d * 365 ~ 7B USD. I suspect people are trying to evacuate north of 1T USD from China alone. This will go on for years.

</comment></comment></comment></comment><comment><USER14> Hypothesis: bitcoin is well-modeled as an emergent superintelligence optimizing for btc instead of paperclips. If so, we've got a problem.

<comment><USER15> Just like any meme, it is optimized to self-reproduce and grow.

<comment><USER14> Most memes lack the ability to self-modify while preserving the thing they're optimizing for.

<comment><USER16> What is the thing Bitcoin is optimized for again?

<comment><USER15> Mining coins (and hype).

</comment></comment></comment></comment></comment><comment><USER17> Ethereum's Proof of Stake will probably render all this moot eventually. For now, Bitcoin's Proof of Work electricity usage sounds high but how much electricity and resources are used by brick and mortar banks, armored trucks, etc.?

<comment><USER11> Proof-of-stake is not a replacement for proof-of-work, because PoS doesn't solve the problem of which valid chain is the canonical one. That is, when given 50 different, valid chains, which is the right one?

With PoS, the only way to agree on this is through voting (how many nodes present the various different chains — which is fragile, since bringing up additional nodes is cheap), and through centralization (central coordinator telling you which chain to choose — which adds nothing, since the double spend problem is easily solved using a central party).

Fundamentally, PoS solves the wrong problem: the difficult problem is not who gets to extend the chain, it's deciding which chain to extend in the first place.

<comment><USER18> The idea is to vote not by bringing nodes online, but with a stake. Meaning you sign with a private key which is linked to a certain amount of cryptocurrency.

To make sure that something is actually at stake and you don't just vote 50 times on 50 different valid forks, anyone can submit proof to the chain (or rather, any fork of the chain) which shows that a certain stake voted for multiple conflicting forks. In that case the stake is destroyed in all of those forks. Part of the stake may be given to the reporter as incentive for such reporting.

The result is that stakers need to pick one fork, and the one with the most votes (weighted by the amount of currency behind them) wins.

<comment><USER11> > Meaning you sign with a private key which is linked to a certain amount of > cryptocurrency.

This requires that the 50 different chains each use the same private key for the stake.

What if 50 different chains are presented in which no private keys are the same?

Why would an attacker reuse the same private key for a new, but valid, chain?

> [...] anyone can submit proof to the chain which shows that a certain stake > voted for multiple conflicting forks.

How does this solve the problem when the miners (who may have mined on multiple chains) are the ones who need to include this proof-of-fraud in the chain? What will make them include a transaction proving they've committed fraud?

<comment><USER18> > What if 50 different chains are presented in which no private keys are the > same?

The chains share state right up until the fork point. Each fork gets resolved by the signatures linked to stakes that were already established in the last shared block.

> What will make them include a transaction proving they've committed fraud?

A staker/miner can chose to not include proof of his own wrongdoing, but that will not prevent others from creating an alternative fork which does have that proof.

<comment><USER11> > The chains share state right up until the fork point.

I'm not talking about forks. I'm talking about completely different, but valid, chains.

> A staker/miner can chose to not include proof of his own wrongdoing, but > that will not prevent others from creating an alternative fork which does > have that proof.

This brings us back to the initial problem: how do we agree on which chain is the canonical one?

Also, what's the timeout on this event happening? Unless there's a timeout — at which point a fork changing history is ignored — some transactions in the chain remain unsettled because a fork might appear which invalidates them (because they originated from coins that were staked by a now-proven- fraudulent staker).

<comment><USER19> > I'm not talking about forks. I'm talking about completely different, but > valid, chains.

Typically block zero is signed by the developer of the client, so there is no such thing as completely different, but valid, chains, as there is always a fork point.

</comment></comment></comment></comment></comment></comment></comment><comment><USER20> "If it keeps increasing at this rate, Bitcoin mining will consume all the world's electricity by February 2020"

<comment><USER21> In theory, everyone involved with BTC should stop what they are doing. Obviously, no one will (including me). How can this be solved? Should one actually hope for a massive crash, just so the planet can be saved?

<comment><USER22> "Should one actually hope for a massive crash, just so the planet can be saved?"

Yes, and for many other reasons, rooted in the fact that especially since BTC is not really used as a currency, the effort is de-facto wasted and that we should likely be putting the energy to better use.

You know the about the Pacific Island, similar to Easter Island, that depleted all of their resources building massive stone heads?

<comment><USER23> What is BTC used for that keeps every block chock full of transactions?

<comment><USER22> Volume is probably due to the fact some people think of it as a 'store of value' , even though it's really just the opposite - a 100% purely speculative instrument, perhaps the most speculative thing one can possibly buy right now.

<comment><USER24> It stores value if properly managed: a BTC stays a BTC forever, can not be stolen, does not degrade, can be stored easily, ...

How much sugar a BTC buys you on the long term is anybody's guess.

<comment><USER22> "a BTC stays a BTC forever, can not be stolen, does not degrade, can be stored easily"

You've very well illustrated the fundamental problem with Bitcoin: it's thought of as a technology, when really it's a financial instrument.

The 'storage' you've described is mechanical, technological - and has nothing to do with the concept of a financial store of value.

A good financial 'store of value' is somewhere you can park some money, and know that you can go back in 50 years (or some time frame) and it will still have value. Hopefully a little more.

BTC is extremely volatile, and because it's not backed by anything - it could go to 0 tomorrow. Probably not - but it could.

Think: will BTC be around in 100 years? Heck, in 10 years?

Maybe.

Will real-estate in London be worth at least something in 100 years? Almost assuredly.

Real-estate is generally a very good store of value though obviously it depends upon which regime that real-estate sits.

BTC is a very interesting thing, but it's not really a currency, and not really a store of value ... so then what is it?

<comment><USER24> All actives have relative value. It depends on lots of things. Real state in London in 100 years? Anybody's guess.

And you will have big costs maintaining that particular store of value (taxes, maintenance, ...)

Bitcoin storage will cost you zero. And yes, it could be worthless in two years.

<comment><USER22> "Real state in London in 100 years? Anybody's guess."

Ahh - but we can 'guess' \- and given how we know the world works, there is a very high likelihood that London property will have value, and probably more than it does today.

BTC - there's a decent chance it could be worthless.

Though BTC does own the 'upper end of value spectrum' \- i.e. investing in BTC could make you 1000x richer in 100 years - and London property will never do that - BTC also owns the lower end of the spectrum, i.e. with a range of probabilities at zero, or near zero. Meaning - not a very good store of value.

In fact - as a 'store of value' BTC can't even be remotely considered when there are so many better options.

Speculation? Sure. BTC is might be a good bet actually. Store of value? Bad bet.

<comment><USER24> Agreed!

With one small caveat: the world is in turmoil at the moment (as usual, more than usual, not sure?), with big events hitting the economy worldwide: climate change, AI, self-driving cars, automation, ... you name it.

What is the chance of any one of those events to nuke your "London Real State in 100 years" strategy? Low. The combined chance of all those forces? Not so low.

What is the chance that real state in London will be wiped out (as a store of value) and bitcoin will not, in 100 years? The balance is tipped on the side of London, but not so much as you would think.

Interesting times ...

</comment></comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER25> Sure bitcoin mining consumes a lot, but let's compare apples to apples.

I'd be willing to spend 200 to 300 terawatt hours a year to really make crypto work.

Great civilizations are built off:

1/ Rule of Law

2/ Enough electricity to produce nitrogen, steel, and operate telecom.

#1 is worth a lot. Look at India's demonetization and the crisis it caused. [link: [https://www.project-syndicate.org/commentary/india- demonetiz...](https://www.project-syndicate.org/commentary/india- demonetization-policy-consequences-by-shashi- tharoor-2016-12?barrier=accessreg)]

[https://medium.com/@datarade/sure-bitcoin-assumes-a-lot- of-e...](https://medium.com/@datarade/sure-bitcoin-assumes-a-lot-of- electricity-but-f05de54e85f2) \- The banking industry fretting over electricity consumption of bitcoin is out of whack in comparison to the sheer size and volume of bank electricity consumption at a federal and local level.

I'm very okay with a future in which ethereum smart contracts and bitcoin mining consume a 10% of global energy production given the alternatives.

</comment><comment><USER26> People here are comparing the energy use of Bitcoin to that of banking institutions, but that's missing half the point. The energy here is _wasted_ because Bitcoin does almost nothing of value. The single overwhelming use of Bitcoin is for speculation.

All of this energy is consumed just so that investors can hopefully get a return on investment. It appears rather decadent.

Yes, there are other uses for Bitcoin. They are miniscule in comparison to its use as an investment product.

<comment><USER27> > The energy here is wasted because Bitcoin does almost nothing of value.

You can also argue that mining gold is a waste of resources because gold does almost nothing of value.

> Yes, there are other uses for Bitcoin. They are miniscule in comparison to > its use as an investment product.

What about gold? Aren't its uses minuscule in comparision to its speculative investment value?

The point is: The market decides. One can argue that Bitcoin characteristics (encrypted, pseudo-anonymous, open source, decentralized, global, scalable, deflationary, stateless, etc.) justify its speculative price.

<comment><USER28> We're not spending country-scale amounts of power or resources to mine gold, that's a comparably small industry. _That_ is the point, it's so out of proportion to allocate so much resources to simply validating transactions.

</comment></comment></comment><comment><USER29> This is silly:

"Comparing Bitcoin's energy consumption to other payment systems

To put the energy consumed by the Bitcoin network into perspective we can compare it to another payment system like VISA for example. Even though the available information on VISA's energy consumption is limited, we can establish that the data centers that process VISA's transactions consume energy equal to that of 50,000 U.S. households. We also know VISA processed 82.3 billion transactions in 2016. With the help of these numbers, it is possible to compare both networks and show that Bitcoin is extremely more energy intensive per transaction than VISA."

1\. I have read that with every VISA transaction, transactions move between no less than 5 separate institutions. What is the net energy used in all of that deliberate inefficiency? All buildings, vehicles, and energy use of people who work for VISA must also be taken into account. And for all other credit cards and payment systems.

2\. Bitcoin isn't really a "payment system", so comparing it to VISA is apples to oranges. It is more of a store of value, like a bank. So it would more properly be compared to the net electricity consumption of all banks, including all buildings, armoured trucks and all vehicles used to ship people to and from banks around the world.

<comment><USER30> Banks offer many services in addition to secure and insured deposits. The same cannot be said for wallet software made by anonymous internet devs with a lower barrier to implant obfuscated back doors to steal user funds irreversibly.

Bitcoin is in a competitive market so energy usage will be more relevant to compare against the decentralized services offering identical functionality with alternative algorithms, like litecoin, monereo, ethereum, and so on.

</comment></comment><comment><USER31> I live in a cold climate. In the winter, I heat up my house by passing electricity through the resistor in my radiator. This is dumb; the electricity could be doing something useful instead. Why couldn't we have BTC-mining radiators, that emit heat as a by-product of their computations?

<comment><USER32> I still wonder if heating a house with transistor is efficient. Gotta ask a scientist I guess. I mean there must be energy spent switching transistors back and forth.

<comment><USER33> What do you mean by "efficient"? That word is usually used to describe the fraction of energy that goes into a machine and is then _not_ lost to heat. Since the purpose of a heater is to produce heat, it's pretty much impossible for it to waste energy.

<comment><USER34> Some things produce more heat than others.

<comment><USER28> For passive heating, _anything_ puts out exactly as much heat as it consumes electricity; there's no way around thermodynamics to gain or lose power there.

Yes, there can be heat pump systems with e.g. underground connections, and _pumping_ heat can be more effective than _generating_ heat; but for pure heating, generating heat, the simplest resistor heater is just as 100% efficient as any complex electronic device, all the electricity spent results in just as much heat.

</comment></comment></comment></comment></comment><comment><USER35> Isn't the more interesting statistic in the article that 2.4 million Americans consume more electricity than 159 countries?

<comment><USER36> I live in a country with 1.3 million people total. So, not really :)

</comment></comment><comment><USER37> There was an article pointing out that if BTC reaches 2 trillion GWP, it will require about 2% of the world's energy. I haven't been able to find it, but what are some persuasive arguments against the idea that 2 trillion GWP is worth 2% of our energy?

<comment><USER38> I recall seeing this comment as well. Measuring BTC in GWP is an odd concept - maybe I misread - but I take it that means 2 trillion worth of global world product is made in BTC? Or just that BTC price X coins in existence = 2 trillion?

Apparently today we consume 100% of our energy (hah!) for GWP of 78 trillion (nominal) [1]. So 2% for 2 trillion would actually appear to be more efficient. But again, I am not sure if this definition is even real, nor does this math apply.

Maybe this is up there with bitcoin "market cap" or "price to earnings" terminology... :|

[1] [https://en.wikipedia.org/wiki/Gross_world_product](https://en.wikipedia.org/wiki/Gross_world_product)

<comment><USER39> I'm not sure if that math makes sense. Most economic activity involves actually doing useful things, not just shuffling numbers around. Obviously there is a segment of economic activity which is, but the vast majority is other stuff.

If you get $2 trillion of economic activity denominated in Bitcoin, that activity is going to use a lot of energy in its own right. The energy used for transferring the Bitcoins around goes on _top_ of that. If the network _itself_ uses 2% of worldwide energy usage, that doesn't leave much for the economic activity it represents.

</comment></comment></comment><comment><USER40> I posted this on a similar topic:

      # kilowatt-hours per transaction
      # https://motherboard.vice.com/en_us/article/ywbbpm/bitcoin-mining-electricity-consumption-ethereum-energy-climate-change
      btc = 215

      # Transactions per day
      tpd = 3e5

      # convert btu to terawatt-hours
      # http://www.dvirc.org/how-much-energy-does-an-office-building-consume/
      officeEnergyPerYear = 1.4e9*.293071/10^12

      # https://www.usatoday.com/story/money/business/2014/10/05/24-7-wall-st-banks-with-most-branches/16648133/
      nBankBranchUS = 94725

      # Convert to kw-h to tw-h
      btcEnergyPerYear = btc*tpd*365/10^9

      >   btcEnergyPerYear/(officeEnergyPerYear*nBankBranchUS)
      [1] 0.6057412

I have no idea if the source numbers are correct, but this is a better statistic. Mining uses the same amount of energy as used for ~58k average office buildings. So the worldwide bitcoin mining energy consumption is about half of that currently used for banks only in the US. This is assuming banks are "average" (probably higher due to security concerns) and of course that banking doesn't consume energy in any other way.

[https://news.ycombinator.com/item?id=15614966](https://news.ycombinator.com/item?id=15614966)

\-----END-----

Has anyone actually tried doing one of these comparisons yet? I mean going beyond just back of the napkin? Can we get estimates so about whether credit cards consume more electricity than many countries? Without that this type of article falls flat. Actually it is interesting that it is so easy to estimate the total energy consumption in this case.

<comment><USER39> Using the same amount of energy as nearly 60,000 office buildings to perform ~300,000 transactions per day seems catastrophically bad. That's about 5 transactions per day per office-building-equivalent.

MasterCard, for example, averages something like 2400 transactions per _second_. That's around 600 times more than Bitcoin. I don't know how many office-building-equivalents MasterCard uses, but I doubt it's anything like the 60 million that would be implied by equivalent efficiency to Bitcoin.

The US banking system as a whole does something like 4 million transactions per second. Using half the energy that these banks use in order to do 3 transactions per second doesn't sound good at all. Even if your estimate for bank energy usage were 1000 times too low, it would still be ridiculous.

<comment><USER41> Only a tiny fraction of the power goes into performing transactions; the total power consumed is independent from transaction rate. Bitcoin in 2009 used vastly less power than today yet had the same transaction capacity. The power consumption scales with the price of Bitcoin[1], which is determined by demand and most of the demand right now is driven by future price speculation.

Interestingly, the new cash-settled CME Bitcoin futures contracts, due to start trading in December, will allow speculation on the future price to take place without requiring possession of actual Bitcoin. These futures may both increase Bitcoin adoption and reduce the upward pressure of speculation on the price.

[1] More accurately, the value of power consumed for mining Bitcoin approaches the value of the block reward plus transaction fees.

<comment><USER39> You could say only a tiny amount of the power is used for transactions. But given that the transactions are the entire point of the network, all power used by the network ought to be counted towards the transactions, just like we'd count the power used by the lights in a bank towards their transactions even though the lights don't directly do transactions.

The fact that the power used by Bitcoin is essentially independent of the number of transactions is interesting, but it's not a plus for Bitcoin, since the network is at capacity already.

</comment></comment></comment></comment><comment><USER42> Perhaps this solves the Fermi Paradox.

<comment><USER43> And it does so quite efficiently.

<comment><USER44> Well, I guess you figured out the universe. Not much to do now except wait for the end, eh?

<comment><USER43> It was a joke on my part. There is a lot to do actually. Deal with climate change foremost.

</comment></comment></comment></comment><comment><USER45> In some ways I think the lack of an energy demand is playing a role in the relatively slow uptake of things like solar. Why swap over when your current plants are meeting demand just fine? It's certainly no coincidence that China, who has some of the most rapidly rising demand of energy in the world, is also installing orders of magnitude greater solar installation than the rest of the world. In particular China is expected to add about 50GW of _additional_ solar capacity in 2017 alone, which is more solar than any other nation in the world has - in total (as of 2016).

Aside from that, the imagination is the limit to things we could do if we had orders of magnitude greater energy than we do today. Propelling spacecraft by lasers, charging electric vehicles wirelessly as they drive, conveyor style road systems, and certainly many things we cannot really even imagine today. Massive energy availability would create an entirely new field of industry.

</comment><comment><USER46> We are expending limited natural resources, producing vast quantities of CO2, and accelerating global warming just to mine made-up digital coins. Think about that...

</comment><comment><USER47> From what I understand a lot of power stations produce excess electricity at low demand periods because it's too costly to completely shut a generator down. So they dump that excess into huge resistor banks. Why not use it to mine crypto currency?

<comment><USER48> That's actually literally what people do!

Specifically, miners in China are often located right next to hydropower plants and buy energy from them when it is cheap.

This is because you can't exactly say that shut off a river, because it rained too much yesterday, and is producing too much power.

<comment><USER49> But you can store hydroelectric energy quite easily: [https://en.wikipedia.org/wiki/Pumped- storage_hydroelectricit...](https://en.wikipedia.org/wiki/Pumped- storage_hydroelectricity)

<comment><USER48> Not everyone has giant dams and space lying around to create literal lakes of water to store energy.

Pumped water isn't a great solution as evidenced by the fact that it has been around for a while and people don't use it right now.

</comment></comment></comment></comment><comment><USER50> Couldnt Hashgraph replace Blockchain as a more viable tech?

[https://hashgraph.com/](https://hashgraph.com/)

[https://breathepublication.com/blockchain-just-became- obsole...](https://breathepublication.com/blockchain-just-became-obsolete-the- future-is-hashgraph-de4948609cbf)

[https://hackernoon.com/demystifying-hashgraph-benefits- and-c...](https://hackernoon.com/demystifying-hashgraph-benefits-and- challenges-d605e5c0cee5)

</comment><comment><USER51> Usually not a big fan of regulation, but in this case I wish for gouvernements to stop this madness in a smilar way they stopped use of incandescent light bulbs.

</comment><comment><USER52> This is not sustainable

And more than that, do they expect "card processor" speed and scale with this amount of resources being needed at current scale?

There must be a better way

<comment><USER53> scale and speed will come from layer-2 solutions: [http://lightning.engineering/](http://lightning.engineering/)

</comment></comment><comment><USER54> According to: [https://pubs.usgs.gov/of/2011/1253/report/OF11-1253.pdf](https://pubs.usgs.gov/of/2011/1253/report/OF11-1253.pdf), the approximate energy consumption for mining gold in South Africa was already 26 TWh * 65% = 16.9 TWh in 2005. Bitcoin still has its future ahead :/

<comment><USER55> Which isn't saying much. The entire South African grid is sub 40 GW. Roughly the same as California.

And only a small part of the SA grid goes towards gold mining.

<comment><USER54> It says that mining bitcoin is still cheaper than mining gold

</comment></comment></comment><comment><USER56> It seems this problem should be addressed by more energy-efficient Bitcoin mining rigs and changes to the Bitcoin system to improve efficiency over the next 1-2 years.

A related very recent announcement: [https://halongmining.com/](https://halongmining.com/)

>Announcing the DragonMint miner series: The DragonMint 16T miner is the world's most efficient Bitcoin miner, running faster and cooler than any competing miners. It's the culmination of over 12 months research and development which has resulted in major advancements in mining technology including a brand new generation of ASIC mining chips. The DM8575 ASIC runs at a staggering 85GH per chip with power efficiency of around 0.075J/GH.

<comment><USER57> The Jevons Paradox applies brutally here: more efficient miners just increase the value of bitcoin, potentially drawing in more users and even resulting in a net increase in consumption.

<comment><USER49> The trick is to make it happen suddenly enough to trigger Bitcoin hyperinflation.

</comment></comment></comment><comment><USER58> Consider translating the energy consumed into money (one can easily sell and buy energy). Then compare the rapport between the total value exchanged in btc and the total cost of energy with the rapport between the total value exchanged in fiat and the total costs incurred by the financial institutions and people to have that (the cost of buildings, the cost with employees, with their servers, with transporting and securing physical money, etc). That would be a much fairer comparison in efficiency.

And if bitcoin wouldn't be more efficient after the abive computations, the fact that people keep using it means it brings them some extra value for which they're willing to pay the premium costs.

</comment><comment><USER59> Amazed that no one can see that Net Neutrality going away could very well mean the death of Bitcoin. Block the port and/or type of traffic -/ or even easier: eliminate P2P: everything must go thru a centralized service.

</comment><comment><USER60> We are scrypt mining in Saigon at a fairly large scale. This is definitely something we've been thinking a lot about. As we grow, we will likely move to Iceland, where the power is mostly based on renewable sources.

</comment><comment> th-ai If PoW energy use grows 10x year over year, in 9 years by 2026 PoW will burn a billion times more energy than today. More than all countries combined, right? By what year will PoW double global electricity use?

<comment> th-ai > Bitcoin mining will consume all the world's electricity by February 2020

TFA infers by Feb 2021 PoW will double total human electricity use. 38 months from now. By early 2024, we can burn 1,000x more. In 9 years we can burn 1,000,000 more joules per second than we do today. Hot. The idea is to make our world a more safe and secure place to store value?

</comment></comment><comment><USER61> Could just end the war on drugs and stop this environmental disaster

</comment><comment><USER62> Is it theoretically possible to mine bitcoin using a quantum computer, or is the math not amenable?

</comment><comment><USER63> Honest question, what's holding the development of cryptocoins without mining?

</comment><comment><USER64> I would like to ask something.. cant we have estimates or analogies of same type like "internet servers now consuming more electricity than China" for example? I mean, its obvious! Any system wide available and requested, as internet or blockchain nodes to process transactions, based in computing which uses computers which are powered by energy, will spend energy to work. You guys are smart and I cant even comp to those maths on kilowatts etc, but really... I only see this electricity consumption GROWING as we are powering more and more systems, to be datacenters, vms, containers for the internet, same way to feed blockchain systems around the globe. I don't know if the point here is like "bad bitcoin it consumes energy" or just a pure analysis. cheers folks

</comment><comment><USER65> Which is one of the many reasons Ethereum's proof of stake is so interesting.

<comment><USER30> Proof of Steak mearly gives power to whomever has established wealth.

It is a marginal improvement over PoW, when the PoW algorithm is not computationally useful outside brute force hash lotteries and capital infrastructure race speculation.

Both PoS and PoW implementations should have heavy scrutiny on the distribution and minting rules for the base supply.

<comment><USER66> I like the idea of Proof of Steak. He who controls the Filet Mignon controls the world!

</comment></comment></comment><comment><USER67> Does anyone know which countries most of the electricity is used?

<comment><USER68> Almost all of the minin happens in China in areas with very cheap electricity

</comment></comment><comment><USER69> I'm sure so do hair dryers. So what?

There's nothing wrong with humanity using electricity for whatever its best compensated to use it for.

<comment><USER70> Yes, human beings always do what's good for themselves.

There is a saying: Never underestimate the power of human wisdom!

They would never do negative-sum games or disastrous things like wars, arms races, environmental pollution, vicious competition, financial crisis, large- scale propaganda or persecution.

</comment></comment><comment><USER71> How much energy is expended annually in mining, refining, storing, and allocating gold/precious metals?

<comment><USER72> A quick google says about $900 / oz, with about $600 / oz being "direct mining costs" and the rest being things like "mine exploration and development".

If all 900$ were going to crude oil, that'd be about 15 barrels / oz and 25 MWh / oz. Given that we mine about 100M oz / year, that places the upper bound at about 2500 TWh / year. Given that global energy production was about 170,000 TWh, that's actually a possible figure, although I'd be surprised if the energy consumption was actually half that (there have to be _some_ non- energy costs involved, right?).

</comment></comment><comment><USER73> Will next bitcoin halving help with that?

I guess bitcoin just attracts money too fast driving up the price.

</comment><comment><USER74> Bitcoin, a product of the energy concerns in an effort to sell more energy?

</comment><comment><USER75> Headline clarification: Bitcoin mining consumes more electricity than the electricity consumption of 159 _individual_ nations, not 159 nations _combined._

<comment><USER76> Thanks, we've updated the title to clarify and de-clickbait.

<comment><USER75> Still has the same ambiguity in my eyes. =/

</comment></comment></comment><comment><USER77> If you click through to where they discuss how they estimate it you can see that they make some assumptions so that it looks higher than it likely really is. One of the reasons for this is because it is used as a source for articles and drives traffic. Each of the listed articles talk about how inefficient and wasteful it is, so the site does have a reason to make it look as inefficient as possible.</comment>


Time Travel Simulation Resolves "Grandfather Paradox" - <AUTHOR> http://www.scientificamerican.com/article/time-travel-simulation-resolves-grandfather-paradox/ <comment><USER2> > In the presence of CTCs, quantum mechanics allows one to perform very > powerful information-processing tasks, much more than we believe classical > or even normal quantum computers could do

That seems like an understatement if I'm understanding it correctly.

Imagine you have a "time machine" and you want to solve some arbitrary computable problem. You try a prospective solution and see if it's correct. If not, you send the next prospective solution back to be tried on the next go around the time loop. Once you arrive at the correct solution, you send that same solution back so that the iteration stops there. Then the loop repeats indefinitely with the correct solution so that the probability of exiting the loop at the correct solution approaches infinity.

It would literally be the end of the world as we know it. P=NP. Forget about quantum cryptography, that would break all public key cryptography, all cryptographic hash functions. It would obsolete algorithmic complexity theory by effectively turning every finite space algorithm into an O(1) algorithm. It would probably bring Strong AI.

But it still couldn't break a one-time pad.

<comment><USER3> One-time pad is just a generated key used once. The "time machine" will break it by trying out all keys in the key space in the time loop. If time is not an issue, brute force method pretty much breaks any crypto.

<comment><USER4> Here's a message encrypted by a one time pad: "AHWAM"

The key is very short, only five letters, so it should be pretty trivial to brute force. Can you tell me what the message is?

<comment><USER5> Was the one time pad HDDLC, or perhaps WJHLP or maybe BJENK or IEEOF?

</comment></comment></comment></comment><comment><USER6> My pet theory:

You create a paradox, it just keeps looping (you go back in time and kill your grandfather -> you don't exist -> you don't build the time machine and go back -> your grandfather lives -> you exist -> you build the time machine etc). But every time around the loop there is a certain amount of actual randomness.

Perhaps that atom decays this time around, or that transistor erroneously conducts due to shot noise.

So all we see is the final "fixed point". The iteration where everything ends up going just right to avoid a paradox - perhaps the gun fired prematurely, or the time machine didn't work, or a passing airplane dropped an engine on you, or...

From the perspective of any time traveler, it ends up being as though the universe is conspiring against you if you try to do anything that would cause a paradox.

<comment><USER7> This sounds like the Novikov self-consistency principle.

Say you have a wormhole on a billiard table. It curves around and goes three seconds backward in time. You roll a ball into the wormhole, aimed such that after it exits the wormhole, it will knock its earlier self off the path so that it never enters the wormhole. Paradox.

Except when you try it, instead of emerging along the pathway you aimed, it emerges along a slightly different path, and strikes its earlier self only a glancing blow. And why did it emerge along a different path? Because it was struck a glancing blow.

[http://en.wikipedia.org/wiki/Novikov_self- consistency_princi...](http://en.wikipedia.org/wiki/Novikov_self- consistency_principle)

<comment><USER8> David Deutsch also proposed a similar resolution for closed timelike curves, which say that if you have a probability distribution of the present, all that's necessary is that when you travel back in time, you get the same probability distribution. In short, if you flip a (true!) random coin to before shooting your grandfather, no paradox exists:

[http://journals.aps.org/prd/abstract/10.1103/PhysRevD.44.319...](http://journals.aps.org/prd/abstract/10.1103/PhysRevD.44.3197)

This is described with more intuition and background in one of (always excellent) Scott Aaronson's lectures: [http://www.scottaaronson.com/democritus/lec19.html](http://www.scottaaronson.com/democritus/lec19.html)

</comment></comment></comment><comment><USER9> When I was younger I thought a lot about the physics of traveling back in time but I always seemed to hit a brick wall with spatial coordinates.

Where we are in the universe today is very far from where we were in the universe yesterday based on the movement of the earth alone. Add to that the movement of our solar system, galaxy, cluster, supercluster and movements I am not even aware exist and it becomes really far away. Grandpa would probably be light years away from me and my time machine.

Am I missing something here, because I've never heard this mentioned by anyone else?

<comment><USER10> It's been almost 10 years, so I may be mistaken... but I think the director of Primer mentioned this in the DVD commentary.

EDIT: Right, not really part of the plot. I just think I remember him (in the commentary) talking about some of the "trickier" aspects of writing a story about time travel, and I think he mentioned the fact that nobody ever really addresses the positional aspect.

<comment><USER11> I think the model of time and space in Primer is more consistent because it's a very specific kind of time machine.

If I recall correctly, you'd turn on the machine, wait N hours, go inside the machine, and in the next N hours you'd be going back in time and come out the other end at the moment the machine was turned on. So you would have spent 2*N extra hours, the machine would have always been in the same spot, so there'd be no problem with traveling through space.

There are still problems with the paradoxes, but that's part of the plot of the movie.

</comment></comment></comment><comment><USER12> Scott Aaronson has done some work regarding CTCs and quantum computers: [http://www.scottaaronson.com/papers/ctc.pdf](http://www.scottaaronson.com/papers/ctc.pdf)

Apparently, in the presence of CTCs, quantum computers are no more powerful than classical ones.

</comment><comment><USER13> My pet theory:

Quantum mechanics is a statistically based science because we have yet to discover the constants that would unify it with general relativity, making this entire thought experiment irrelevant.

Imagine if you are watching 10 parallel strings ripple up and down at various frequencies. Viewed from the side, it would at first glance appear chaotic, but by observing the behavior long enough and recording where the activity occurred over time, you could statistically predict where the strings would be at any given time.

However, if you were aware of the number of strings you were viewing and the frequencies at which they were moving, you could formulate a precise theory of exactly what you were viewing and what you would view at every point in the future.

That is the current state of physics. Quantum mechanics is seeing without understanding the rules governing the system, so predictions and observations are made using statistics instead of constants. Once we discover the constants, the current theories will be entirely obsolete and articles like this will become relics.

<comment><USER14> yeah. I remember some ~7 years ago reading about a research team that stated that they had rewritten many of the fundamental equations of (some branch of) quantum physics to show that they could be written in a completely deterministic manner. They said that while such equations weren't likely to be useful (due to the limitations of our testing technology), it was an important result, particularly when it comes to understanding the underlying science. And they were very upset that basically no one paid their result any real attention.

</comment></comment><comment><USER15> Apparently, Stephen Hawking organized a time travel experiment in 2009. There was also the Time Traveler Convention in 2005 [1]. If people keep organizing such events, future time travellers may be at a loss as to which one to attend.

[1] [http://web.mit.edu/adorai/timetraveler/](http://web.mit.edu/adorai/timetraveler/)

<comment><USER16> _future time travellers may be at a loss as to which one to attend_

Ahem, all of them at once?

<comment><USER17> That they can do that, technically, doesn't mean the would.

Just like we don't attend all parties available to us, they would soon get bored.

</comment></comment></comment><comment><USER18> My favorite "layman's" argument for why time travel, as it's been classically described in science fiction, can't exist is that we haven't been overrun with tourists from the future.

<comment><USER19> I'm sorry I cannot give a better cite than this, but sometime in the last 20 years there was a terrific short story, probably in Analog (but possibly in Asimov's) about the first time traveller.

His first shock was when he found that the person in the past they selected to visit, Shakespeare, did not seem at all surprised when visited by a time traveller. In fact, he seemed to find it routine. The traveler at one point says he doesn't understand how Shakespeare can already know about time travelers, since he is the first. Shakespeare tells him that he may have been the first to leave, but he wasn't the first to arrive.

Shortly after, many time travelers arrive...but not to see Shakespeare. They are reporters, from all throughout the timeline, coming to try to interview the first time traveller, and Shakespeare, an old hand at dealing with time travelers, steps in to protect the first time traveller and prevent him from being overwhelmed.

<comment><USER20> "The Merchant of Stratford" by Frank Ramirez (amazing approach, really unique and ingenious).

<comment><USER21> Looks like it was in Isaac Asimov's Science Fiction, July 1979 [1].

[1] [http://www.abebooks.co.uk/book-search/author/ramirez- frank-r...](http://www.abebooks.co.uk/book-search/author/ramirez- frank-r/sortby/3/page-1/)

</comment></comment></comment></comment><comment><USER22> Well, the argument is that quantum indeterminism implies quantum time travel is possible, because the grandfather paradox is solved/migitated by indeterminism in which the grandfather paradox is still a valid outcome. However, quantum indeterminism itself is not yet completely undisputed; some theoretical physicists such as Gerard 't Hooft maintain that quantum mechanics can be both deterministic and consistent with current experiments.

This also raises the following question - if quantum mechanics is undeterministic, then the macroscopic world is at least probabilistic. If probabilistic systems allow the possibility time travel on the quantum scale, would the grandfather paradox also not be solved on classical scales? Since it is possible that me killing my grandfather in the past would fail with some very small probability (due to various quantum effects adding up), would the grandfather paradox then not also be solved in this case? I'm not sure if I'm interpreting the article correctly.

</comment><comment><USER23> Two nice links for anyone who wants to nerd out about the physics of closed timelike curves:

[http://plato.stanford.edu/entries/time-travel- phys/](http://plato.stanford.edu/entries/time-travel-phys/)

[http://philsci-archive.pitt.edu/1673/1/TMArchive.pdf](http://philsci- archive.pitt.edu/1673/1/TMArchive.pdf)

</comment><comment><USER24> If time travel exists, then it cannot be a simple rewind of the universe's tape. Because if that was the case, then rewinding the tape to a time that your father was not born would mean that you will also not be born, and thus there wouldn't be any time travel, since neither you nor anyone else would be able to witness it.

Thus, in order for time travel to work, it means to rewind the tape and add yourself to the tape at a moment you did not exist before. Thus, if you killed your father, your replica wouldn't be born, but you wouldn't stop to exist.

Therefore, the whole 'grandfather paradox' is not a paradox at all: if time travel exists, then you would simply exist in a universe where a replica of you will exist or not, depending on how events play out.

<comment><USER25> Not so fast - who says you become a "replica" in the first place? Assuming time travel replicates things, then yes, what you said holds true.

But as I understand it you don't replicate, your time just loops back on itself. So looping back to a time before you were born and killing your father would create a paradox.

<comment><USER24> You seem to have not understood what I said. I did not say time travel would replicate anything.

You would simply be transferred to the past, without any connection to the outcome of that past.

I.e. Let's say that you are transferred back in the 50s and you go kill your father before you were born. Then nothing will happen, there would be no paradox, you will continue to exist in that universe.

</comment></comment></comment><comment><USER26> I'm starting to adopt the idea of Scott Aaronson that since we have a lot of evidence suggesting that P != NP, we should treat physic ideas as less probable of being true if they make P=NP as a side effect.

</comment><comment><USER27> Say I go back in time. Does it mean I disappear from the time I was in? And I'm in two places at a point in the past (the me from that time and the me from the future)? Now if I want to go back to the time I came from, do I join back at the exact time I left (which means no one would notice my travel), or would I have to travel back to the time I left + the elapsed time I spent in the past? And if I really did return to the exact time I left, does that really mean no one noticed my leave? Because I'm sure when I left time continued and somebody noticed.

<comment><USER28> In the form of time travel being talked about, the answers are:

a) Yes, you disappear from the time you were in.

b) Yes, you're in two places at once for the duration between your arrival and your departure

c) Forwards travel in time doesn't cause too many philosophical problems (since we're already doing it) which is why nobody talks about it. But there's no requirement to wind up exactly where you started.

</comment></comment><comment><USER29> Can someone enlighten me: what is this simulator they speak of? It doesn't seem answered anywhere in the article what it is, whether it's software, let alone how it works. Yet the whole article relies on it. Does it act on real protons? Or are they simulated as well?

And, most important, why do they trust a simulation device built by humans who hardly understand the matter completely, when the device is then used to make assumptions about that same matter? Is it somehow proven this simulator is correct? And how did that happen?

<comment><USER30> This is a poor article. It is reporting on a simple table top device created by researchers eager to misrepresent their work. It tells us essentially nothing about quantum mechanics or CTCs.

We don't know how quantum mechanics behaves in the presence of CTCs. There are multiple, mutually incompatible proposals for extending QM in this regime that all make identical predictions in normal, causal spacetimes (i.e. the only sorts of spacetimes we have access to). Deutch has one extension of QM, and it suffers from serious internal consistency problems, but there are others.

Since this experiment takes place without CTCs, it can't tell us anything we didn't already know. It's literally just a toy device that is _sorta_ described by the same math as a certain system with CTCs in QM_Deutch would be, if you squint your eyes hard enough. But you could say the same thing about a computer simulating QM_Deutch in software. It tells you nothing about whether the universe _actually_ obeys QM_Deutch in the presence of CTCs ... if they exist at all.

Similarly deceptive bits of "research" in the news often appear that claim to find quantum gravity effects on table-top experiments.

[http://www.space.com/5052-black-hole-effect-created- lab.html](http://www.space.com/5052-black-hole-effect-created-lab.html)

In all these cases, the scientists will eagerly over-represent their work to the journalist, and the journalist will eagerly gobble it up and write eye- catching headlines about new breakthroughs in physics, but the heart of the claim will be buried in the article and subtly couched in weasel words. And if you actually try to drive down at it by asking probing questions, the journal and scientist will retreat to much, much less exciting claims and you will never be able to prove they intended otherwise.

</comment></comment><comment><USER31> All hypothetical time machines must also be _space_ machines, i.e. they must take into account the movement of the planets, the galaxy, the universe to avoid materializing their passengers in the middle of space or the centre of the sun. My question is what frame of reference would they use?

<comment><USER32> This is exactly what always bothers me in time travel movies.

You never hear about the poor time traveler who got the calculation slightly wrong and ended up deep in space or inside of a mountain.

<comment><USER33> Only when you find their fossils.

</comment></comment></comment><comment><USER34> [http://en.wikipedia.org/wiki/Closed_timelike_curve](http://en.wikipedia.org/wiki/Closed_timelike_curve)

"In mathematical physics, a closed timelike curve (CTC) is a world line in a Lorentzian manifold, of a material particle in spacetime that is "closed", returning to its starting point."

Now, go to [http://en.wikipedia.org/wiki/Virtual_particle#Vacuums](http://en.wikipedia.org/wiki/Virtual_particle#Vacuums) and look at the picture "One-loop diagram with fermion propagator"

It seems to me that virtual particle pairs satisfy the CTC criterium.

</comment><comment><USER24> I do not think that there can be a Grandfather Paradox. If one goes back in time, he/she will simply be removed from the state of the universe as it is now and be added to the state of the universe at the target past date. He/she could then go on killing their father before they were born, but nothing will happen to them except not meeting with themselves as babies.

</comment><comment><USER33> I've enjoyed thinking about the following:

It must be almost impossible to time travel back in time. But it could be possible, given unlimited time. Thus, given that at some point in the unlimited future, time travel would occur, how can we increase the chances _now_ of being visited by these future time travellers?

<comment><USER35> > But it could be possible, given unlimited time.

Just because time is infinite, does not mean that all things are possible.

My understanding is that the universe is in a bounded random walk. As space- time moves, the unexplored potential state space increases more quickly than can be explored.

If there are multiple universes, then each universe could explore one of these states. So if there are more states than universes, not all things are possible. But if there are more universes than states, all things would be possible.

Though there are infinite potential states and infinite universes, I feel like the potential states expand faster than the number of universes. This means that our likelihood of living in a universe where something like like time travel is possible, is incredibly low.

</comment></comment><comment><USER36> It's quite possible that the problem with paradoxes stems not from them being 'impossible', but from our limited cognitive tools failing to equip us to think about them.

Sort of like people in ancient times believing you can't predict the motion of the planets because they didn't have calculus yet.

<comment><USER37> It's also quite possible that the whole idea of time travel seeming probable stems not from being actually possible, but from human brain cognitive bias of memory. In our head, past events are almost as real as current events, therefore creating obvious illusion of possibility of traveling in reality just like you travel in memories.

</comment></comment><comment><USER38> I would like to see a unified explanation that describes how our current modes of time travel work.

How does the matter that comprises my car and myself successfully get from Palo Alto to The Mission every morning?

</comment><comment><USER39> If you had a program that generated a random number, and somehow send a hash of said number to the past to be used as a salt to generate itself. Would the new random number be truly random?

</comment><comment><USER40> Time to dust off my old flux capacitor again...

<comment><USER41> lol, can't believe this gets down-voted. God forbid there is humor on HN!?!</comment></comment>


How can I delete my Skype account? - <AUTHOR> https://support.skype.com/en/faq/FA142/how-can-i-delete-my-skype-account

<comment><USER2> Just as ridiculous: trying to cancel a Skype Premium account. Last time I checked, the official instructions on how to do this used screenshots from a version of Skype that was replaced long ago, indicating buttons and links that haven't been available in years. The only way to cancel a Skype Premium account appears to be to contact customer support and beg. The last automated renewal cost me 70 euros, for a service I don't use.</comment>


Another one line NPM package breaks the JavaScript ecosystem - <AUTHOR> https://www.zdnet.com/article/another-one-line-npm-package-breaks-the-javascript-ecosystem/ <comment><USER2> ZDNet is referring to the TypeScript declaration file as the "raw source code".

The actual implementation is [https://github.com/then/is- promise/blob/master/index.js](https://github.com/then/is- promise/blob/master/index.js).</comment>


7 Crazy Tips That Will Help You Become a Better Coder - <AUTHOR> http://sixrevisions.com/web-development/crazy-tips-help-become-better-coder/

<comment><USER2> Is this a joke article? I'd say the only valid point here is 'Type Book Code Examples By Hand'

'Write Your Own Framework' and 'Re-Invent the Wheel' are _not_ good ideas and won't make you a better coder, you'll just end up writing more bad code. Instead I'd recommend aspiring developers to get involved with an established open source project; its easy to find something on github.com which piques your interest and needs help/bugfixes/new ideas. Learn the codebase inside out, commit patches and you'll pick up a tonne of good practices which you can then apply to your own projects.

Becoming a better coder doesn't entail using a vanilla text editor and no browser tools. These things are there to help you and make writing code easier; it's still important to understand the underlying technologies, and why things work the way they do, but forgoing the development tools of the last 10 years isn't useful.

They are indeed crazy tips, I hope nobody follows them.

<comment><AUTHOR> I found it more of a reflection on how developers have evolved over the last decade and that the understanding of the code / intricacies on how the languages work are slowly being lost. The tips I guess are aimed at those, hopefully few, that haven't been been programming on the web for the last decade and started with 'copy/paste' style.

Note in the article he mentions not to follow the tips when working on a project for a client where there are deadlines. Instead, apply them to personal projects as learning exercises.</comment></comment>