Yitang Zhang, 2014 MacArthur Fellow - <AUTHOR> http://www.macfound.org/fellows/927/

<comment><USER2> Yitang Zhang has an incredibly inspiring academic story of perseverance and passion in the face of adversity:

> After graduation, Zhang had a hard time finding an academic position...He > managed to find a position as a lecturer after many years, at the University > of New Hampshire, where he was hired by Kenneth Appel back in 1999. Prior to > getting back to academia, he worked for several years as an accountant and a > delivery worker for a New York City restaurant. He also worked in a motel in > Kentucky and in a Subway sandwich shop.

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

(UNH is ranked #108 in math nationwide.) I highly recommend that article in _Quanta_ :

[http://www.simonsfoundation.org/quanta/20130519-unheralded-m...](http://www.simonsfoundation.org/quanta/20130519-unheralded- mathematician-bridges-the-prime-gap/)

<comment><USER3> His advisor's memoir is also interesting:

"So after Yitang graduated, I told him the normal way of seeking jobs. When I looked into his eyes, I found a disturbing soul, a burning bush, an explorer who wanted to reach the north pole, a mountaineer who determined to scale Mt. Everest, and a traveler who would brave thunders and lightnings to reach his destination. Yitang never came back to me requesting recommendation letters. Apparently, he did not seek a job. Even to the date Yitang announced his monumental result I did not know what was the best for him. Though I was sure of one thing, − he could not survive the life of "tenure-track," "tenure," and "promotions". It was not his type. I regarded him as a free spirit, and I should let him fly."

[http://www.math.purdue.edu/~ttm/ZhangYt.pdf](http://www.math.purdue.edu/~ttm/ZhangYt.pdf)

</comment></comment><comment><USER4> You know academics is a bit fucked when someone being anointed a MacArthur fellow was a "lecturer" at UNH from 1999 until being promoted to "professor" in January of 2014! The plus side being someone like Mr. Zhang gets to stay working on interesting academic problems.

I know several people getting their PhD, lecturing, and assistent professors.. but I only know one person on a tenure "track" and they want desperately to quit. We as a society have got to figure out how to incept public research institutions.

<comment><USER5> Yitang Zhang is an outlier in that sense, like Alexander Grothendick and Grigori Perelman. Many other great mathematicians, like Terence Tao, Timothy Gowers, etc. and even some working on 'big problems' like Andrew Wiles are in stable academic jobs. If his own words [1] are anything to go by, Zhang's situation is probably due to his adviser's unwillingness or inability to recommend him for good academic positions.

[1] [http://nautil.us/issue/5/fame/the-twin-prime- hero](http://nautil.us/issue/5/fame/the-twin-prime-hero)

<comment><USER6> Andrew Wiles had to do all the work in secret while releasing old papers as a cover.

</comment></comment></comment><comment><USER7> I love that articles relevant in mathematics gets posted to HN, it just makes me giddy.

Also, that note on a possible application in crypto makes sense to my amateur brain.

<comment><USER8> The article that got to me first was from ABC news ([http://abcnews.go.com/US/wireStory/2014-macarthur-genius- gra...](http://abcnews.go.com/US/wireStory/2014-macarthur-genius-grant- winners-unveiled-25555604)).

Making only a sidenote that the group of recipients includes a mathematician, they also say "Most winners are not widely known outside their fields ..." I thought Zhang deserves a bit more recognition than this, especially since his rise from "relative obscurity" is pretty unique.

</comment></comment><comment><USER9> Pure math is interesting. The research topics are often out of the left field and have no bearing on any current application. How do people pick research topics that can't be seen useful for a long time?

Kudos to Zhang for his perseverance.

<comment><USER10> Its not so much about the solution being useful, its more about finding out if the solution exists. Its sort of a self challenge, like a mental marathon. Generally speaking there isn't much need for you to run 26 miles, let alone do it very fast.

But you do it, for the challenge, the learning, and to grow as a person. Because the finish line isn't why your running, your running because you like running.

</comment></comment><comment><USER11> I read this a while ago but am happy to find new links in this post, what a great story! Printed it out for my kids to read too.

</comment><comment><USER12> What an inspiring story...</comment>


D.E. Shaw and how computer geeks and English majors transformed Wall St. (2018) - <AUTHOR> https://nymag.com/intelligencer/2018/01/d-e-shaw-the-first-great-quant-hedge-fund.html <comment><USER2> What a marketing submarine! [0]

Let me count the vastly more transformational and earlier quantitative funds just off the top of my head: Princeton Newport, Commodities Corporation, Tudor, RenTech, Chicago Research; hell even Soros and the Tigers were more influential and just as quantitative. DE Shaw was an early mover for certain kinds of automated trading, but if he had never met Nunzio Tartaglia (and basically stole his secret sauce -hey at least they mentioned Morgan Stanley), he'd still be writing shitty papers on parallel computing models at Columbia. He got lucky, and was able to take advantage of his luck, but he is also a garbage human being who has made the world worse[1][2]. His company once offered me a job: I told them to go fuck themselves, and the only better "no" decision I made was saying no to Bear Stearns in 2006.

[0] [http://paulgraham.com/submarine.html](http://paulgraham.com/submarine.html)

[1][https://nymag.com/intelligencer/2019/09/david-e-shaw- college...](https://nymag.com/intelligencer/2019/09/david-e-shaw-college- donations.html)

[2][https://www.propublica.org/article/hedge-fund- billionaires-d...](https://www.propublica.org/article/hedge-fund-billionaires- donations-college-admissions-elite-universities)

<comment><USER3> re [1][2]:

It's not clear to me how donating 10s of millions of dollars to prestigious universities in order to secure a grand total of 2 spots for his kids has made the world worse.

<comment><USER4> It's clear to me that the message that a sufficient amount of money let's you subvert the rules weakens trust in society and increases justification for an every man for himself strategy.

<comment><USER5> Subverting the rules doesn't equate to making the world worse.

Assuming just $10m for 2 of his children to be admitted? That's enough to fully fund the education of ~50 low-income students [1].

I personally believe we should turn these quiet donations into a public bidding process instead to maximize what colleges can receive and ensure it's done in as fair of a way as possible, but that's separate.

[1] It's important to distinguish that the donations went to the university, not a corrupt official at the university. This is actually productive.

<comment><USER6> Maybe the universities could start offering to give rich people's kids automatic 4.0s, too, if they donate twice as much. Sure it undermines the system and acts as an insidious poison into the idea of meritocracy, but think of how many scholarships it could pay for!

<comment><USER4> This already happens:

[https://www.latimes.com/california/story/2020-07-16/qatar- pr...](https://www.latimes.com/california/story/2020-07-16/qatar-prince-usc- ucla-la)

[https://theunionjournal.com/qatar-prince-awarded-usc- masters...](https://theunionjournal.com/qatar-prince-awarded-usc-masters- degree-despite-barely-attending-classes-middle-east-monitor/)

It's a shame how easily the reputation of the US higher education is being ruined. If an entity that already has billions of dollars in endowments can be corrupted, what chance does society have?

</comment></comment></comment></comment></comment></comment><comment><USER7> Is David Shaw brilliant? Absolutely. Has the quant/technology revolution been a positive development for financial markets? No doubt.

But secondary trading is still a zero-sum game. Firms like D.E. Shaw are profit maximizing and extract a huge amount of value from society. Probably less than the old boys club they replaced, but probably much more than necessary. There is a great deal of competition among quant trading firms overall, and their rise has coincided with electronification of markets, tighter spreads, lower commissions - all good things. But if the forces of capitalism are truly working, you have to wonder why so many firms like these continue to print money year after year (although there have been some new developments-- for example, stock exchanges have gotten much more effective at monetizing their access and data feeds, which has really put the squeeze HFT market makers; still, zero-sum game though).

There's no good reason we can't have it all: efficiently-priced modern- technology financial markets without these huge rents being pulled out. And I shouldn't pick on quant firms specifically - every layer of the system extracts its share, and I'd argue brokers and exchanges are much worse since they're fiduciaries and semi-regulatory entities, respectively, and riddled with conflicts of interest.

Disclaimer: former co-founder/head quant at IEX (Flash Boys), current CEO of Proof Trading (YC S19)

<comment><USER8> "probably much more than necessary"

How exactly do you decide how much is _necessary_?. And is there any reason to think that they are extracting value from _society_ rather than _other market participants_?

And is there any evidence that having one company make a billion dollars from other market participants is somehow worse for the system than having a million companies make a thousand dollars each?

The low spreads and liquidity are not some fact of nature - I'm pretty sure that a lot of it comes as a result of many people competing with each other to _try and make money_. I agree there are lot of people trying to screw their clients to make money in both the retail and the institutional markets (I used to work in sales for an I-bank). And I agree that those areas with conflict of interest are badly policed and do NOT help market structure or society as a whole. But my impression is that DE Shaw is a prop trading firm - where is the conflict of interest?

<comment><USER9> GP is in agreement with you on the last point, and the highlighted conflicts of interest are not related to DE Shaw:

"brokers and exchanges are much worse [than DE Shaw] since they're fiduciaries and semi-regulatory entities, respectively, and riddled with conflicts of interest."

<comment><USER8> I understand that - what I'm hoping is that dcaisen will clarify what exactly their concern is with DE Shaw. I'm claiming that other than conflict of interest, having firms like DE Shaw make lots of money is not a problem. I'm hoping that if there is some non-conflict-of-interest reason why it's harmful, they'll explain and I'll learn something useful

<comment><USER9> I'll let dcaisen speak for himself, but I don't get the impression that he believes DE Shaw is actively harmful; just that the service they provide (market liquidity, low spreads) comes at a relatively high cost. "How?" is a perfectly legitimate question, and it looks like a problem he's actively working on as the CEO of Proof Trading.

<comment><USER10> If he believes that, then he doesn't understand what DE Shaw's business is. It's like confusing a bakery for a flour mill.

</comment></comment></comment></comment></comment></comment><comment><USER11> Wondering what D.E. Shaw did after getting rich? He used his money for building a specialized super computer ([https://en.wikipedia.org/wiki/Anton_(computer)](https://en.wikipedia.org/wiki/Anton_\(computer\))) which runs molecular dynamics simulations for drug development. His 2008 computer still runs molecular dynamics simulations about an order of magnitude faster than general purpose super computers in 2020.

<comment><USER12> So that's where Gilfoyle got the name Anton from...

<comment><USER13> I thought it was an Anton LaVey reference [https://en.wikipedia.org/wiki/Anton_LaVey](https://en.wikipedia.org/wiki/Anton_LaVey)

</comment></comment></comment><comment><USER14> I passed a series of phone interviews with DE Shaw and they flew me to NY to interview on-site many years ago. It was for a statistician / machine learning role.

Once I arrived on site they asked me to write a program to rotate a matrix on the whiteboard. The catch was, it had to be in syntactically correct Tcl, a language I had never heard of, which was not on the job listing, not discussed in any of the phone interviews, and not on my resume.

I clarified that I had never heard of that language and no one gave me any information that I had to prepare to answer questions about it and the two interviewers in the room said it was required for the job. I offered to code it in Python but they said it had to be Tcl. I was freaking out at this point, sweating, wondering if I was mixed up with a different candidate.

I said the role I was interviewing for and asked if it was possibly a mistake, they replied it was not and they expected me to write Tcl for that solution.

I thought maybe it was some kind of finance bluster sort of thing, like to test if I would stick up for myself or offer an outside the box idea.

I sat down from the whiteboard and said if they could explain to me the syntax of Tcl I would give it a try.

The interviewers both thanked me for my time and said the next interviewer would be in shortly (I had a printed sheet of a 9-5 full day of scheduled interviewers).

I sat and waited in that room for over 45 minutes, no one came to get me, nothing. Eventually I walked back to the main reception desk area and explained what happened, and the attendant person looked me up on a computer and said all my interviews were done for the day, I was free to go, and they would be in touch. The point of contact was someone named Isaac Torres. I went back to the hotel they put me in which was right across the street, feeling incredibly depressed, and just ordered food and stayed in. My flight was the next evening, but around 11 am before I even left the hotel, Isaac called me to say they were going to pass on me.

It was a weird thing. I wasn't even mad because it was so absurd, like getting struck by lightning or something. It was like surrealism, irrational.

But I sure did walk away feeling like DE Shaw the company is absolutely fucked internally, and I would never in a million years consider working for them and would try to warn anyone I can away.

<comment><USER15> they paid for your flight and hotel?

<comment><USER14> Yes they did that, but they had scheduled me for 9-5 on the day of the interview, which doesn't entitle them to waste my time by having one unprofessional interview session followed by me sitting for 45 minutes and being told I can go. I could have scheduled other things or planned my time differently if I had known it would only last ~90 minutes, or even that it lasting less than the full 9-5 based on realtime decisions was a possibility (it was not described as a possibility).

<comment><USER15> I agree with you. For that kind of disrespect I would not only need to get paid for hotel and travel, but my time too. And waisting my time costs like 100x more per hour than my normal rate. Seeing as they cheapened out here by only paying hotel and travel, what does that say about how they treat their employees comp wise? Doesn't look good. For that alone I would avoid them like the plague.

</comment></comment></comment></comment><comment><USER16> I hate to rain on everyone's parade but no one transformed Wall Street. If you saw how most of the banks are run and who is in charge of these places up close there would be a run on the banks. Everyone would be withdrawing their cash and storing it under their mattress.

</comment><comment><USER17> Paperclip maximizing AI. It's so interesting that the long-form narrative of a trading house omits to dive into the detail of _a single_ actual trade!

<comment><USER18> Because all the computer hocus pocus is obscuring how they make money: they launder arbitrage banks are not allowed to do to their own clients in exchange for a large fee.

<comment><USER19> I am going to need a pretty good citation on that

<comment><USER18> There isn't going to be documentation out there, in some pithy Bloomberg article, "Banks have prized relationships with arbitrageurs that help them monetize opportunities that plainly violate fiduciary duty."

Information about how hedge funds work - like information about say how ad tech firms work - is incommensurable with HN's Reddit/Wiki-style way of disseminating knowledge. I hope that information without citations could be tolerated more, I have no dog in this race, I just like sharing knowledge.

Shaw and many hedge funds that have been around for decades acquire smaller arbitrage firms that can be thought of as having "licenses" to perform arbitrage. This portfolio of arb is how they scale to their AUM.

There is nothing actually secret or protectable about what an individual arb firm does to execute the trade. For example a particular HFT trading algorithm. Such firms that rely on actual secrets do not last long and so in a Darwinian way do not wind up in the portfolios of huge funds like DE Shaw.

The arb shops that last a while have permission, from a bank, that depends on a relationship with a real human being, that is exclusive to the firm granted, to launder a particular form of arb the bank would like to do but could not.

For example you're allowed to take a spread as a bond trading desk, but wouldn't you like to sell the bank's bonds instead of its competitors bonds? That's plainly against fiduciary so it "doesn't happen." Instead you go to an anonymous arb firm, for $1m in bonds, and you say, "okay we're going to sell you the bond that is actually ours, you will sell it back to us, here is your fee, now we can sell this bond back to the client and wash the fact that it is ours." Nobody says that! But that is the economics of the trade, why the arb firm can make money for so long, why banks work with them despite seeming to be "parasites," etc. The computers are just part of the hocus pocus of laundering that arb.

Shaw doesn't actually come up with this arb or necessarily source the relationship. Instead it finds the little anonymous arb firm and buys it, and carefully scales the relationship for $1m of bonds with 1 bank to $1b in bonds with 10 banks. The risks in Shaw's business are that you lose the license to arb. The _upside_ is from investors persistently underpricing the ability for Shaw to _scale_ this arb from $1m to $1b. No, they basically pull a rabbit out of a hat every year and continue to scale a particular arb further than people thought was possible.

Also, nobody is going to want to just give Shaw, a bunch of rich people, a bunch of free money. But you can't fight their ability to acquire little arb firms. This is the way.

<comment><USER20> > Instead you [the bank] go to an anonymous arb firm, for $1m in bonds, and > you say, "okay we're going to sell you the bond that is actually ours, you > will sell it back to us, here is your fee, now we can sell this bond back to > the client and wash the fact that it is ours."

How does the bank _make money_ doing this? Routing the sale of this bond through the "anonymous arb firm" doesn't do anything to the price. If the bank's competitor is selling their bond at 1.00, the bank could directly offer their bond at 0.99 without getting "anonymous arb firm" involved. If the bank routes the trade through the "anonymous arb firm"... what difference does that make? If it shows up on the market at 1.01, the bank still has to give the client the 1.00 bond first, and if it shows up on the market at 0.99, the bank could have just done that itself.

</comment></comment></comment></comment></comment><comment><USER21> They have a huge non-quant business. I believe they are actually mainly a non- quant firm now.

</comment><comment><USER22> There was another famous hedge fund noted for mathematical excellence but it turned out to be a different story entirely ...

<comment><USER23> [https://en.wikipedia.org/wiki/When_Genius_Failed](https://en.wikipedia.org/wiki/When_Genius_Failed)

<comment><USER24> Amazing book. Truly astounding sequence of events.

Greatest irony of all, they named their firm "Long-term Capital Management", while taking hugely leveraged short-term positions ($1 trillion dollars worth of derivatives backed by about $100 billion or so assets) that were beyond the understanding of anyone else. Didn't last 4 years before they blew. They did show 40% annual returns when they started and I guess that's what kept them going without much regulation. But man, did they crash hard. Investors who were returned their money after a year or 2, and those who were turned down from even investing must have thanked their Gods for saving them from absolute destruction.

There is another book by Michael Lewis (who also wrote "The Big Short") called "The Liar's Poker", where he talks about his time at Salomon Brothers and how they collapsed in a very similar fashion. Highly levered derivatives with a magic formula that has worked well (so far..). It's fascinating how they were allowed to do what they did. Open gambling with client's money, and no repercussions on loosing it all. "Blowing up a customer" was apparently common and chalked up to a rookie's mistake. "Baptism by fire". How did the rookies even get access to millions of dollars of money to bet on crazy derivatives!!

I feel that every time a major upset in the financial markets lands on us, it is because some group of really talented people managed to convince everyone that they discovered something that no one else has and have "cracked the market" by showing consistently high returns for a period of time, and gain access to huge pools of capital. Only, after a few years the market turns around, showing a side of things that they did not take into account and the whole thing goes belly up, market crashes, loads of people loose money, mostly its everyone else but that group (leverage, borrowing, access to someone else's capital etc).

And because everyone who was supposed to keep them in check did not do it because despite it being their job not to, they did take them for their word, they try to cover it all up by paying the very people who caused all the trouble and who were supposed to watch out for all this.

Banking world seems to have a lot of conflict of interest all around. It is much better now, with lots more rules and regulations, but it is still there.

</comment></comment></comment><comment><USER25> When you find a loophole in market

        you'll inform the authorities to correct it
        you'll make money out of this anomaly

DESCO chose the 2nd option; The devil is in details.

</comment><comment><USER26> Ed Thorp's Princeton/Newport Partners was the first great quant hedge fund.

<comment><USER27> Jim Simons/Renaissance were the first great quant hedge fund. For the last 30 years their annualized returns, after fees, is 39%.

<comment><USER28> The medallion fund began at Axcom under Elwyn Berlekamp and RenTech bought it.

[https://en.wikipedia.org/wiki/Elwyn_Berlekamp](https://en.wikipedia.org/wiki/Elwyn_Berlekamp) [https://en.wikipedia.org/w/index.php?title=Axcom_Trading_Adv...](https://en.wikipedia.org/w/index.php?title=Axcom_Trading_Advisors&redirect=no)

<comment><USER10> Rather more precisely, Simons hired Ax to pursue a dream he'd first had with Baum in the 70s, using math to predict markets. Ax had some success, but the Medallion Fund didn't take off until after he left. Berlekamp gets a little credit, but wasn't really there long enough to have major impact. If you want to know who did the real work, figure out who Simons paid the most.

<comment><USER29> Who did he pay the most?

</comment></comment></comment></comment></comment><comment><USER30> I am confused. This article is very positive about DE Shaw. Nonetheless, it says DE Shaw is a "$47 billion firm [assets underlying management (AUM)], earning its investors more than $25 billion". That is a return of 53% which sounds good until you consider the firm was started 32 years ago - at which point the compound interest rate is less than 1% a year. I realise the AUM has likely grown over time, but this rate of return is less than inflation at a time when the market has grown considerably. This is a negative return while, per the article, many employees have become millionaires and Shaw himself a multi billionaire. From the article it appears that DE Shaw is good at is attracting assets underlying management and paying themselves well without providing value to their customers. What have I missed?

<comment><USER31> Umm... you're missing that the firm has not always been $47 billion? You think DE Shaw was started 32 years ago with 47 billion dollars?</comment></comment>


Jef Raskin's 1979 proposal for web-like Apple Computer Network - <AUTHOR> http://library.stanford.edu/mac/primary/docs/bom/applenet.html

<comment><USER2> Agree with comments re: Raskin's self importance over stated.

That being said, he did bring my hero into the fold, the amazing Bill Atkinson. Atkinson is who inspired me to get into programming. Viva la hypercard!

</comment><comment><USER3> my feeling is that jef raskin had a whole bunch of good ideas in his life, most of which failed to reach fruition due to the fact that he was irascible and far too difficult to work with. a shame, really.

<comment><USER4> Didn't he try to mislead people by saying he started the Macintosh project?

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

"He later hired his former student Bill Atkinson from UCSD to work at Apple and began the Macintosh project in 1979. He also recruited Andy Hertzfeld and Burrell Smith from the Apple Service Department. The machine he envisioned was very different from the Macintosh that was eventually released and had much more in common with PDAs than modern GUI-based machines. The machine was similar in power to the Apple II and included a small 9-inch black-and-white character display built into a small case with a floppy disk. A number of basic applications were built into the machine, selectable by pressing function keys. The machine also included logic that would understand user intentions and switch programs on the fly. For instance, if the user simply started typing it would switch into editor mode, and if they typed numbers it would switch to calculator mode. In many cases these switches would be largely invisible to the user."

<comment><USER5> I see your point about misleading people... I always read how he was the "father of MacIntosh" but after you read more you realize that was never the case.

"For instance, if the user simply started typing it would switch into editor mode, and if they typed numbers it would switch to calculator mode. In many cases these switches would be largely invisible to the user."

Ouch... talk about doing way too much. This would drive most people insane. We should all be thankful to Jobs that he took over MacIntosh team and never implemented any of this stuff.</comment></comment></comment>


A Step by Step Guide to Using Dropbox - <AUTHOR> http://www.jonathanmacdonald.com/?p=1196

<comment><USER2> I love Dropbox. So simple, and yet, so awesome.

</comment><comment><USER3> Is it just me or is it funny that the title says "Step by Step" and the homepage for dropbox (drop.io) is a list of steps?

EDIT: I'm stupid

<comment><USER4> That's not the homepage of Dropbox. It's <http://getdropbox.com>.</comment></comment>


Cream drummer Ginger Baker died this morning. He was 80 - <AUTHOR> https://www.theguardian.com/music/2019/oct/06/ginger-baker-wild-and-brilliant-cream-drummer-dies-aged-80 <comment><USER2> Sad - and makes me feel old! Remember seeing him live as part of Ginger Bakers Air Force circa 1970 ish. Remember the gig well but not the date!</comment>


LightSail 2 Spacecraft Successfully Demonstrates Flight by Light - <AUTHOR> http://www.planetary.org/blogs/jason-davis/lightsail-2-successful-flight-by-light.html <comment><USER2> My understanding of what's going on here is that the light sail isn't aiming or changing at all. It's just a big sail, in orbit.

When it's moving away from the sun, the sail is being pushed "forward", which adds to it's velocity- this increases the apogee on the opposite side of the orbit. When it's moving towards the sun, the sail is being pushed "backwards", lowering it's current velocity and reducing the perigee. As the perigee comes lower, it spends less time in that end of the orbit, where it's gaining velocity, and when it's apogee is high it spends more time in that end of the orbit, where it's losing velocity. It's not a winning strategy I'm afraid.

But imagine! Imagine if we had a slightly different solar sail. One that could retract and expand at will, via solar powered electric motors. Then we could have it open it's sails when the "wind" is favorable, then close them when it's not. It could slowly but surely escape earth's gravity well, and gracefully travel around the solar system. A big enough one might even be able to accelerate right out of the solar system.

<comment><USER3> I didn't work on Lightsail, but the article implies that it does aim the sail. It isn't expanding/contracting, but it does change orientation using the reaction wheels. Basically, they turn the sail broadside to catch the sunlight to raise the orbit, and turn it on edge when they don't want the extra drag.

This particular satellite won't ever leave orbit because the sail can't overcome even the tiny amount of atmospheric drag. If you want to achieve escape velocity with a sail you'll need a bigger sail and a higher orbit to start out. Right now it's only feasible for small satellites and we've been able to achieve escape velocity using rockets for decades.

Eventually, I do envision a competition to see who can get a payload to Mars with the least amount of fuel. Kind of like the fuel efficiency challenges that college engineering departments participate in today.

<comment><USER4> > a bigger sail and a higher orbit

But a bigger sail would increase the atmospheric drag!

<comment><USER3> But the higher orbit would reduce the drag. You could probably get away with the same size sail, but you've got to start high enough that the sail's tiny thrust over its 50% (ish) duty cycle can overcome the drag present in 100% of the orbit. Once you're high enough a bigger sail would mean lifting the orbit faster.

</comment></comment></comment></comment><comment><USER5> Can someone more familiar with orbital mechanics help me understand why it looks like the perigree is coming down in opposite to the apogee?

I'm but a mere KSP player, but I've always thought the perigee comes down in a fairly linear fashion based on drag, which is mostly a function of altitude - I would assume they'd be using the sail to just "burn prograde" whenever the solar angle is possible, raising both the apogee and the perigee, but the apogee coming up way faster?

<comment><USER6> I'd guess the sail orientation is not changing relative to the sun, so at perigee this provides an acceleration (because it's mostly in the velocity direction), which raises apogee. At apogee it provides deceleration (because it's in the anti-velocity direction), which lowers perigee. There are also probably other effects depending on the sail orientation that muck with the inclination and other elements. It's a little different than drag which is always anti-velocity.

I have limited KSP experience and an aerospace degree, so I'd defer to someone with more KSP experience.

<comment><USER5> According to the article though they're already adjusting orientation to adjust thrust, but possibly they saturate too fast and they can't control it enough to truly null the deceleration?

> One such refinement involves LightSail 2's single momentum wheel, which > rotates the spacecraft broadside and then edge-on to the Sun each orbit to > turn the thrust from solar sailing on and off.

</comment></comment></comment><comment><USER7> What about [https://en.wikipedia.org/wiki/IKAROS](https://en.wikipedia.org/wiki/IKAROS)? The only new part, is that Lightsail is a cubesat, right? (IKAROUS was 315 kg.)

From article: "Our criteria was to demonstrate controlled solar sailing in a CubeSat by changing the spacecraft's orbit using only the light pressure of the Sun, something that's never been done before. I'm enormously proud of this team. It's been a long road and we did it."

<comment><USER8> Yes, they demonstrated putting a light sail in a tiny cheap satellite and controlling it

</comment></comment><comment><USER9> > Most spacecraft use chemical thrusters to desaturate momentum wheels; > LightSail 2 relies on electromagnetic torque rods, which orient the > spacecraft by pushing against Earth's magnetic field.

I'm trying to visualise what this process might look like. Having read a bit about momentum wheels it seems like it's probably not a one way street in terms of the direction of torque so the wheel at times might speed up and other times slow down so to avoid saturation. Clearly this is not always possible so an external energy source is used to provide a balancing torque so the wheels can be slowed down without turning the craft (too much).

For the lightsail 2 it uses magnetic torque rods, which from [https://en.m.wikipedia.org/wiki/Magnetorquer](https://en.m.wikipedia.org/wiki/Magnetorquer) are electromagnets so the energy comes from turning them on for a while.

Can anyone guess a bit more or explain where in the orbit the saturation might occur and what this desatiration process would look like in terms of the motion of the craft?

</comment><comment><USER10> If a photon hits the sail and is reflected, it must transfer two photon momentums to the sail. The energy should be less than before it the sail. Is it redshifted?

<comment><USER11> Correct. Consider an initially stationary sail. Even though this isn't physically what is happening, you can imagine the reflection from the point of view of the sail as a photon getting absorbed and a photon of exactly the same frequency being emitted immediately after in the opposite direction. Now, to a stationary observer, the sail will have started moving after the absorption, so the emmitted photon will be redshifted due to the Doppler effect.

It's only be a very tiny amount of course at normal velocities, probably smaller than the energy wasted due to a mirror not being 100% efficient. To extract all the kinetic energy of a bundle of light, you'd have to bounce it between two mirrors many times. Maybe that's a possibility for shorter distances, perhaps during take off?

<comment><USER12> Reflection can indeed be used! However, it's only useful for pushing _apart_ two objects that you've built - e.g. a large station with a mirror and a laser, and a small probe with just a mirror.

This is called a photonic laser thruster ([https://en.wikipedia.org/wiki/Photonic_laser_thruster](https://en.wikipedia.org/wiki/Photonic_laser_thruster)) and is a variant of laser propulsion ([https://en.wikipedia.org/wiki/Laser_propulsion](https://en.wikipedia.org/wiki/Laser_propulsion)). Like a mass driver, it gets around the rocket equation by separating the propulsion system from the spacecraft.

</comment></comment></comment><comment><USER13> In grade school they asked us to make a model spaceship. I made a light sail spaceship. It's really neat that we have a working implementation of the technique .

<comment><USER14> When I was 16 in my physics class the light sale ship (or perhaps just the idea of it) was part of the section where the physics of photons were being investigated (along with stuff like lasers and the photoelectric effect). Fantastic stuff.

</comment></comment><comment><USER15> What I'm curious about is how fast a solar sailing craft could go before the thrust of the photons is balanced out by the drag of the interplanetary medium. Five particles per cubic centimeter isn't much but I suspect it wouldn't be irrelevant for a square mile sail moving at 400km/s.

</comment><comment><USER16> Very cool! I know nothing about solar sails, but I wonder if the craft could have LEDs mounted to it so it could bombard different regions of the sail with photons to make it turn appropriately.

<comment><USER17> If you emit a particle (a photon) and then catch it the net effect will be 0.

<comment><USER16> Net effect is not zero if the photon bounces off of the sail

<comment><USER18> Why use sail then? You can just shoot your photon the opposite way.

<comment><USER19> That would be a "photon rocket" which is an existing idea, but requires a lot of energy, whereas this uses free energy from the sun.

</comment></comment></comment></comment></comment><comment><USER20> Slightly unrelated, but I did a project this past semester in Grad School looking at the economics of a solar sail de-orbiting mechanism to attach to satellites. Seeing the successful demonstration here just gives me the slightest sense of pride and vindication toward the people in the class who said there's no practical use for something like that.

That being said, the project itself was a disaster and I'm glad to have escaped the class with a decent grade despite it.

</comment><comment><USER21> Here is a data dashboard from the telemetry collected via SatNOGS stations tracking LightSail2 [https://dashboard.satnogs.org/d/CBwYeHSZk/lightsail-2?orgId=...](https://dashboard.satnogs.org/d/CBwYeHSZk/lightsail-2?orgId=1&refresh=5m&from=now-30d&to=now)

</comment><comment><USER22> I'm glad they raised the orbit, it's just that it's not enough for me (in the northeast US) to be in the radio footprint of the satellite. It was launched into equatorial orbit with a fair amount of inclination, but elevation angles from my location never exceed 11 degrees making reception difficult.

I was hoping to receive the satellite's Morse code beacon and/or telemetry stream [1]. BTW: Does anyone know the downlink frequency for the photos?

[1] [http://www.planetary.org/blogs/jason- davis/2016/20160609-lig...](http://www.planetary.org/blogs/jason- davis/2016/20160609-lightsail-2-morse-code.html)

<comment><USER23> Downlink frequency is 437.025 MHz. You'll be able to download telemetry, but you won't be able to decode photos because NOAA says no.

</comment></comment><comment><USER24> Can you "tack" a solar sail?

Niven/Pournelle had a cool idea in _The Mote in God 's Eye_ of charging your craft when traversing a magnetic field to change direction (not specific to sails, but another passive technique).

<comment><USER25> Using Earth's magnetic field for attitude control is already a thing [1].

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

<comment><USER26> In fact, that's exactly what LightSail is using to control its attitude: [http://www.planetary.org/blogs/jason- davis/2016/20160418-lig...](http://www.planetary.org/blogs/jason- davis/2016/20160418-lightsail-test-success.html)

</comment></comment></comment><comment><USER27> Why deorbit it though? Why not try for an EM-Lagrange point?

<comment><USER28> They are in a low earth orbit and there is still considerable atmospheric drag in the region. This causes the satellite to deorbit.

This was a technology demonstrator and it has completed its mission successfully. It simply wasn't launched to an orbit where it can do more (Cubesats hitch rides on rockets launching larger, expensive payloads)

NASA does have a mission intended to navigate quite a bit more using a solar sailing cubesat.

[https://www.nasa.gov/content/nea-scout](https://www.nasa.gov/content/nea- scout)

I'm not sure to what extent the mission will rely on the solar sail though.

<comment> ben-schaaf As long as the trust produced by the solar sail is more than atmospheric drag it technically has enough Δv to go anywhere.

<comment><USER29> Solar sail thrust isn't like rocket thrust; you can't just point it wherever you like, or turn it on and off as effectively, and there isn't nearly as much thrust available either. This craft can't leave low Earth orbit.

</comment></comment></comment></comment><comment><USER30> Not really relevant but, if we we had an arbitrarily super fast spacecraft, how would we prevent it from hitting a small rock and exploding?

<comment><USER31> Ultimately, you can't. Space is really, really, really big and empty, though. Unimaginably so, which would make an incident be some really bad luck. In something like the lightsails, you'd just launch multiple simultaneously.

Space is so big and empty that even for something like the asteroid belt you could pass through any point randomly and on average be thousands of kilometers from the nearest rock. Perhaps even tens of thousands.

<comment><USER32> Is it though? To try and quantify risk I looked up how many metoeites hit the earth each day and its 18,000 to 84,000 that are over 10 grams.

Whiile the earth is obviously much bigger than a space craft, you would think should there be a bunch of craft flying around in the future, theres a fair odds of it happening every few years.

Also for example, the ISS has already been hit a couple of times: [https://www.iflscience.com/space/an-astronaut-used-his- finge...](https://www.iflscience.com/space/an-astronaut-used-his-finger-to- plug-that-leak-on-the-international-space-station/)

If we have thousands or 10's of thousands of craft in space in the future I would suspect this will be a very real issue on a semi regular basis.

Take what I say with a healthy dose of skeptism as not an expert or even well researched, but logically on above seems quite a reasonable risk.

<comment> ben-schaaf Things tend to collect around large gravity wells, that's just kinda how that works. I don't think you can compare the ISS in LEO to something traveling within or without the solar system.

</comment></comment></comment></comment><comment><USER33> Would be really interesting now to see a successful experiment with an electric solar sail to get some idea of how the technologies compare in practice - [https://en.wikipedia.org/wiki/Electric_sail](https://en.wikipedia.org/wiki/Electric_sail)

</comment><comment><USER34> We need more of this, and more spending and results in space research. Not only because we are destroying our own planet, but also because we as a species have been stagnating for quite some time.

<comment><USER35> Why spend money on leaving our lovely planet when we could spend money on reducing emissions so we don't have to.

</comment></comment><comment><USER36> Awesome!

</comment><comment><USER37> Ugh this title. Flight by light? A solar sail is not flying. An airfoil generating lift is flying.

<comment><USER33> Balloons, rockets and cannonballs all fly. And the last two do not require an atmosphere to fly in.</comment></comment>


Ask HN: What's your setup to get perfect reading experience? - <AUTHOR> <comment><USER2> Left half of the book in one hand and right half of the book in the other hand, so the book doesn't close itself when I'm reading.</comment>


Ask YC: Best credit card payment processor? - <AUTHOR>

I've heard a lot of horror stories about Paypal, although I haven't experienced them myself. However, I think it would be beneficial to get recommendations for payment processors. Any ideas? <comment><USER2> <http://www.braintreepaymentsolutions.com>

They offer everything the big dogs do, but their staff is incredibly helpful and attentive. We use them on FamSpam and GitHub.

I wouldn't find the merchant with the lowest rates, find the one you like the most. As your business grows, you can always renegotiate your rates.

<comment><USER3> They don't even post their rates anywhere? That always makes me uncomfortable.

[http://www.braintreepaymentsolutions.com/truth-in-pricing- gu...](http://www.braintreepaymentsolutions.com/truth-in-pricing- guarantee/m/7/)

<comment><USER2> Rates vary on sale quantity and average price, it's not a flat fee like Paypal. You need to email them for a quote.

<comment><USER3> I filled out the quote page 4 hours ago... We'll see what happens.

</comment></comment></comment></comment><comment><USER4> you can use our service to find one (we currently only have two partners right now).

<http://www.quotesignal.com>

And when you do get a quote from someone, use this tool to rate it:

[http://www.quotesignal.com/merchant-account-comparison- calcu...](http://www.quotesignal.com/merchant-account-comparison- calculator.aspx)

EDIT: I know it's bad form to complain about downmods. This isn't a complaint just a statement that I'm flummoxed as to _why_ this would be voted down.

</comment><comment><USER5> Firstly what is your product or service? It probably makes a difference who you would choose. For example, if you have subscription payments then Google Checkout isn't in your space (yet). PayPal is an obvious one and I think you can hear "horror stories" about most of them in my opinion - how would your customers perceive you offering payment in PayPal. In theory it could be a negative. Where are you located? Are you wanting to offer in Dollars, Euro, Yen? Give us some more info on what your service/product is and we can help you some more.

</comment><comment><USER6> I coincidentally met one of the principles of Dharma Merchant Services when I was considering which way to go. She was incredibly upfront and didn't push her service ('look at other options and let me know if we can help').

I try to make decisions relatively quickly when the consequences are mild for a sub-optimal solution so that attitude sold me.

Highly recommended: <http://www.dharmamerchantservices.com/>

</comment><comment><AUTHOR> Amazon seems to offer payment processing as well, but it's in public beta. Is anyone using that?

Sorry about being hush on the details, I'll let you guys know it all soon. ;)

</comment><comment><USER7> Cybersource. Far and away. They're great assuming you don't need support, but if you're reading this then you probably don't need no stinking support!

<comment><USER8> The thing about support is that you don't need it -- until you need it.

</comment></comment><comment><USER9> Authorize.net - Game, Set, Match.

<comment><USER10> The only thing going for Authorize.net is that it is supported _everywhere_ in _every_ language and _every_ framework. And, of course, they aren't actually a merchant services provider. They are just a gateway service. You need both to accept credit card payments (if I could find a company that did both really well, I'd switch to them).

Authorize.net is a bit pricey and a bit difficult to use. But, it is the gateway service that we currently use...and when I switched to another shopping cart, we didn't have to change gateway providers or write new processing code. Which was nice.

When we write our own shopping cart (which seems impossible to avoid, because everything we've tried is such a poor fit for the way we sell our software), it won't tie into Authorize.net. It'll use PayPal, Google Checkout, and some other payment gateway (whichever one works with the cheapest merchant services provider, while still offering recurring payment support, probably).

</comment></comment><comment><USER11> I recommend TrustCommerce.

</comment><comment><USER12> www.AlertPay.com

</comment><comment><USER13> lots of ideas - visit :

<http://searchyc.com/credit+card>

<comment><USER14> Or:

[http://www.gabrielweinberg.com/startupswiki/Ask_YC_Archive#t...](http://www.gabrielweinberg.com/startupswiki/Ask_YC_Archive#toc77)

<comment><USER15> Thank you! And thank you very much Gabe Weinberg!

</comment></comment></comment><comment><USER16> www.asiapay.com disclaimer: I'm a director for www.asiapay.com.ph</comment>


Red Programming Language - <AUTHOR> http://www.red-lang.org <comment><USER2> The thing I find the most fascinating about Rebol and Red is their respective type (runtime tag?) systems, which are unusual for modern dynamically typed languages; today you'd expect such things as URLs and file paths to be represented in the language as either plain old strings or classes, not their own basic types. You can see Rebol's and Red's type systems at [http://i.imgur.com/0XFuRmS.png](http://i.imgur.com/0XFuRmS.png) (this is a slide from a presentation deck on Red's about page) and [http://www.rebol.com/docs/core23/rebolcore-16.html](http://www.rebol.com/docs/core23/rebolcore-16.html) respectively.

<comment><USER3> I think the word you're looking for is "literals", i.e. rebol has URL literals (cause there isn't much difference in many modern languages between "basic types" and classes).

I always found that fascinating too.

<comment><USER2> You are probably right. The distinct literal notation for the datatypes (which is what the Rebol manual calls them) is their biggest draw for me.

Although the sequence! and the object! datatype in Rebol are not subtypes of each other they have similar semantics (pass by reference, explicit copying, mutation performed in place by built-in functions like sort).

Objects in Rebol and their literal representation are actually pretty interesting, too. Douglas Crockford cites Rebol as one of the inspirations for JSON, and you can see why when you look at an example:

        >> example: make object! [
            var1: 10
            var2: var1 + 10
            var3: now/time
            set-time: does [var3: now/time]
            calculate: func [value] [
                var1: value
                var2: value + 10
            ]
        ]

        >> print mold/all example ; mold/all serializes data
        #[object! [
            var1: 10
            var2: 20
            var3: 21:42:34
            set-time: #[function! [][var3: now/time]]
             calculate: #[function! [value][
                var1: value
                var2: value + 10
            ]]
        ]]

I haven't read much Rebol application code but as far as I understand serializing objects and storing them on disk as plain text is the norm for configuration and persistence.

<comment><USER4> After reading up a little more about Red on Wikipedia, I came across the term "Homoiconicity"[1] which I hadn't encountered before (though the concept itself wasn't new to me, I wasn't aware there was a name for it). What homoiconicity refers to is where the language syntax mirrors the metadata markup - just as you described here with JSON / Javascript. In fact it's a common feature of LISP and it's descendants, Scheme obviously being one. So it's not that surprising that Javascript also inherited homoiconicity from Scheme.

The other interesting thing about my research on Wikipedia was the tangent it took me on. I started reading about other other homoiconicity languages that I hadn't heard of; and that lad me to a page about the programming language "Curl"[2] (not related to the cURL HTTP client that most Linux / UNIX sysadmins would be well versed in). Curl is very interesting as it merges the different stacks of web development (markup, style sheets and scripting engine) in a unified language that can still be abstracted separately if one so chooses. Baring the syntax, it was exactly the type of concept I was suggesting a little while back when myself and a few friends were discussing ideal world scenarios of how we'd reinvent the web-development stack.

Anyhow, Red is definitely an interesting language in itself. But it's always a bonus when one interesting post on HN leads you on a journey of a few other discoveries.

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

[2] [http://en.wikipedia.org/wiki/Curl_%28programming_language%29](http://en.wikipedia.org/wiki/Curl_%28programming_language%29)

<comment><USER5> JavaScript is _not_ a homoiconic language, because the important feature of homiconicity is not that the syntax "mirrors" the syntax of data, but that the syntax is _actually represented_ as a piece of data that can be manipulated in the language.

For example, in Scheme, I can easily generate data structures and interpret them as code to be executed _or as data to be manipulated_. For example, here I can generate code corresponding to a given factorial, and also muck with it.

        > (define (fact-code n)
            (if (= n 0) 1 `(* ,n ,(fact-code (- n 1)))))
        > (fact-code 4)
        (* 4 (* 3 (* 2 1)))
        > (eval (fact-code 4) (the-environment))
        24
        > (eval (replace '* '+ (fib-code 4)) (the-environment))
        10

We can write a function similar to _fact-code_ in Rebol, which I'm borrowing from an earlier comment[^1]

      >> fact-code: func [n] [either n = 1 [1] [compose [(n) * (fact-code n - 1)]]]

      >> fact-code 4
      == [4 * 3 * 2 * 1]

      >> do fact-code 4
      == 24

      >> do replace/all fact-code 4 '* '+
      == 10

There is no analogous way of generating and manipulating JavaScript code using JavaScript. If _all_ JS code could be understood as JSON that then could be fed back into JavaScript and manipulated there, then it would be homoiconic.

[^1]: Borrowed from this older comment with a minor name change [https://news.ycombinator.com/item?id=5809980](https://news.ycombinator.com/item?id=5809980)

<comment><USER4> My mistake, thank you for the correction.

What made me believe JS / JSON were homoiconic was down to the following vulnerable method of loading a JSON file:

        var obj = eval (json);

But after reading your post, I can see how this differs from homiconicity

</comment></comment></comment></comment></comment></comment><comment><USER6> This site should really have some code examples on the main pages. I shouldn't have to watch videos to get a basic idea of the syntax and what it can do. The blog on the front has some code, but it's not geared towards explaining the basic ideas.

<comment><USER7> Red's author here. I agree and I apology for the currently poor web site. It was built for the Red and Rebol crowd to help them follow us while we are building Red. As we are getting closer to a beta version, we are planning to move in the next couple of months to a brand new site that will properly communicate about Red to newcomers.

About the syntax and semantics, in a nutshell, it's a Lisp without parentheses and with infix operator support. Tokens are separated by a whitespace or a delimiter (very few of them). Code is a tree of lists (called "blocks" in our local jargon), blocks are delimited by square brackets [].

You can have a look here [1] for a larger code and syntax example.

[1] [https://github.com/red/red/blob/master/red.r](https://github.com/red/red/blob/master/red.r)

<comment><USER8> Good to see you have serious plans for this language. I was always interested in Rebol, but never became any 'good' at it --- although I always like to read updates about it and its forks.

</comment></comment></comment><comment><USER9>
        red>> .1 + .2 + .3 = .6
        == true
        red>> .1 + .2 + .3 - .6
        == 1.110223024625157e-16

This doesn't feel right to me. I usually would expect equality to be a strictly exact thing. This is bound to cause some problems in code that assumes IEEE-754 has been implemented exactly.

<comment><USER10> The language distinguishes between equal and "strictly equal":

        red>> .1 + .2 + .3 == .6
        == false
        red>> .1 + .2 + .3 = .6
        == true

I'm not sure if that syntax is the wisest choice, but in the absence of arbitrary precision arithmetic it seems a very good concept, to avoid common IEEE-754 surprises.

They appear to be implementing it along these lines: [http://randomascii.wordpress.com/2012/02/25/comparing- floati...](http://randomascii.wordpress.com/2012/02/25/comparing-floating- point-numbers-2012-edition/)

<comment><USER11> It should be noted that Rebol comes with an arbitrary precision (bignum) arithmetic option via it's _money!_ datatype - [http://www.rebol.net/wiki/Money](http://www.rebol.net/wiki/Money)

      >> .1 + .2 + .3
      == 0.6000000000000001

      >> type? 0.1
      == decimal!

      >> $.1 + $.2 + $.3
      == $0.6

      >> type? $0.1
      == money!

Red will most likely get this soon but perhaps with a different nomenclature (Red as already renamed _decimal!_ to _float!_ ).

</comment></comment></comment><comment> johnk- Another place to learn more about Red and Rebol is over at the stackoverflow chat room. [http://chat.stackoverflow.com/rooms/291/rebol-and- red](http://chat.stackoverflow.com/rooms/291/rebol-and-red)

</comment><comment><USER12> Does anyone has a link comparing Red to REBOL? I was a heavy REBOL user back then and always missed the language. I wonder if Red is a viable substitute...

<comment><USER13> From my reading today it seems REBOL 3 and Red have semi-merged [1]. REBOL 3 extensions can be written in Red, and the communities seem to share the same online spaces and goals.

Red looks awesome in the long run, the main weirdness being its refusal to follow standard math operator precedence [2].

Although Red's macro/DSL buildup skips a ton of intermediate bloat, someone needs to write a normal server framework to interact with standard industry data sources. When it becomes easy to add a Red microservice to an architecture, Red can enjoy an explosion of adoption as Go has.

[1] [http://rebolforum.com/index.cgi?f=printtopic&topicnumber=27&...](http://rebolforum.com/index.cgi?f=printtopic&topicnumber=27&archiveflag=new)

[2] [http://stackoverflow.com/questions/26514041/fixing-the- rebol...](http://stackoverflow.com/questions/26514041/fixing-the- rebol3-example-calculator-to-use-normal-math-operator-precedence)

<comment><USER14> As the person that replied to your second point on the SO question there, I have to add something here. There are other calculators made in Rebol. (Search rebol.org site scripts for those). Having this calculator adapted for the math operator precedence would be too farfetched, for the example merely shows how much can be done with so little code. The other is that I do not have the ultimate say in what Rebol and or Red should do with math operator precedence, I have nothing to say about that to be exact ;-) (I am free to express my opinion on the subject). What I state there still holds for me, the operator precendence is imho arbitrary, and not necessary at all, counterintuitive for kids, and (I am a mathematician) the world can do without these rules. With operator precendence I have no other choice then to use ellipses when I have 3 * 4 + 1 and I meant I wanted to add 1 to 4 before multiplying by 3: 3 * (4 + 1) in Rebol I can write 1 + 4 * 3 and I do NOT have to use "(" and ")" to achieve what I intended saving me four keystrokes.

Regards,

Arnold

<comment><USER15> Does the operator precedence convention of treating addition and multiplication equally apply to all of Red? All of REBOL? Or is it just that program? Thanks.

<comment><USER7> Both Rebol and Red use that convention. It sounds weird at first look, but proved to be a relief in practice (no need to remember any specific precedence rule). Though, we plan to provide a small math-oriented DSL for writing expressions using standard math conventions. It would look like this:

      >> print 1 + 2 * 3
      == 9
      >> print math [1 + 2 * 3]
      == 7

</comment></comment></comment></comment></comment><comment><USER16> I am happy to read that the site will become more accessible to a larger group. I've REBOLed a long time in the 2000s and made good money of it.

Make no mistake: both REBOL and RED have an extremely powerful underlying model model to help solve problems. In a world of containers and micro- services "something like these" will emerge.

If nothing else, that's a reason to follow them - between Go and RED/REBOl you can see a glimpse of computing as it will be.

</comment><comment><USER17> As wonderful as the language might be, the site is nearly unreadable; the black background makes the dark red links almost invisible, and it "swallows up" the thin, small white text.

<comment><USER7> I have replied about the web site on the top comment. I have noticed that the readability varies greatly across browsers/OS/devices. Anyway, the color scheme and layout we are using currently are far from being the best. We will change that before officially opening the doors to our guests. :)

</comment></comment><comment><USER18> Not to be confused with [http://en.wikipedia.org/wiki/Core_War#Redcode](http://en.wikipedia.org/wiki/Core_War#Redcode)</comment>


This is how Big Oil will die - <AUTHOR> https://medium.com/@sethmiller_59231/this-is-how-big-oil-will-die-38b843bd4fe0 <comment><USER2> The article uses anecdotal evidences of hybrid or electrical cars with very high mileage without repairs to project that such cars have much longer lifespan on _average_ than ones with an internal combustion engine.

My anecdotal evidences tell the opposite. With current electrical and hybrid cars a minor collision may require a battery replacement. The batteries just do not handle collision stress well. And that is very costly.

Now, with self-driving cars the situation may change as the risk if collisions drops, but that is still few years in future.

</comment><comment><USER3> Interesting: markets can change fast.

I'm not sure that the savings are as claimed, though my first-order objections are covered by the data in the article.

However, an oil company I divested from when it became clear that it really did just want to be about liquid dinosaurs rather than being a versatile energy supplier, seems from inside info to be back in the 'energy' game and accepting that the 'oil' bit is going away...

<comment><USER2> Norwegian Statoil has started making PR noise about offshore wind farms. But it remains to be seen how really serious they are about that.

In Norway there are a few fast charging stations for electrical cars throughout the country. But I not have seen a single one provided by Statoil or any other gas station operator. At best the companies that built them placed them near gas stations so during 20-30 min of charging on can go there and drink coffee.

</comment></comment><comment><USER4> Am I the only one that clicked on this thinking it would be a tirade against the much-maligned "Big _O_ " complexity notation?</comment>


Ask HN: How do you stay on top of legal work and/or taxes? - <AUTHOR>

I recently received a letter from the State of Utah detailing an owed debt of 3k dollars - 2500 dollars in taxes and 500 in fees/penalties. We formed an LLC entity in late July of last year and have not made any revenue yet. I don't know where I went wrong but I also don't have a great deal of time to look into all the possibilities.<p>Because of this, I've debated hiring an accountant or paying for a pre-paid legal service to help me overcome these types of problems (of ignorance). What are you thoughts here? Should I just stop what I'm doing and spend a week or two learning as much as I can about the legal processes in which my company is bound or should I pay to have someone walk me through it? What are you doing yourself? <comment><USER2> Pay an accountant familiar with Utah tax law. It's possible that you owe much less than the state is asking for. You want someone who has been in a business tax audit before, the learning curve can be steep.

</comment><comment><USER3> I'm sad to say that after the 1986 tax "reform" bill I just gave up on this sort of thing and became a wage slave.

I know from my father that it's a _lot_ of work to keep up on this sort of thing; having an ongoing relationship with a lawyer, retaining an accounting firm, and paying a lot of attention to the issues (back in the bad old days that entailed subscribing to several good newsletters) seems to be safest path. (Check my account and email me if you want me to put you in touch with him for how he did this for 5 or so decades; you might say that startups are in my blood.)

For your case, unless you want to fold the company, it's necessary for you to find out what's going on. If you made a mistake, just paying off this demand is unlikely to prevent ones in the future. If you didn't, well, if you can figure that out without spending too much money you then know you have a $3K legal and accounting budget (minus your opportunity costs) to try to set it right.

</comment><comment><USER4> Those are the two items that I've contracted out.

Legal stuff is usually so specific to the case at hand that you even have to shop around for a lawyer that has the required expertise, accounting is something where small slip-ups can cost you a fortune, your business or a lot of hardship.

Keep in mind though that even if you contract this stuff out you are still responsible. So you should know at least enough about it that you can spot it when things derail.

</comment><comment><USER5> Wow - that sounds like a mistake on the state's part to me so I second the suggestion to get an accountant there.

And to answer your question: I just do. Barely. Enough. I think. However, I've done it for 15 years and I learn a bit more and become a bit more efficient each year.</comment>


Ask HN: How far along does your idea have to be to apply for YC? - <AUTHOR>

I didn't find a definitive answer on the FAQ pages of YC. I think I have a great idea and I'm working on the business plan and such, but I don't have a usable product or even the beginnings of one at the moment. Is it too early for to apply to YC and similar programs if you only have a detailed idea/plan and a bit of the grunt work done? <comment><USER2> I don't think it's too early to apply for YC. We hadn't built anything when we applied (although we had spent a few weeks brainstorming ideas). We built our prototype between when we were accepted for interviews and when we actually interviewed. Even if you don't apply, filling out the YC application is a great way to think clearly about your idea.

YC accepts good people who's ideas they don't like and then try to convince you to do something else. We fell into this category. I wouldn't spend too much time writing a business plan though. Start building things and experimenting.

</comment><comment><USER3> I think a bigger problem for you is the use of "I", YC is very much focused on the team. If you've got a good team with a track record from working together you've got a chance to get in pre-product.

If you're a sole founder you pretty much have to show that you're capable of building a company on your own which essentially requires product and traction.

</comment><comment><USER4> Thanks for asking this question. I was wondering this as well. It's good to hear that very early stage ideas are not shunned altogether, even though we are at a disadvantage to other candidates.

I'm currently following David's advice; questioning my idea using YC application as a reference and starting to get a prototype together.

</comment><comment><USER5> Considering that YC encourages people to apply even if they don't have an idea, and pg has stated in these forums that they accept founders who don't have ideas, you're probably fine.

</comment><comment><USER6> I am looking for partner to apply for YC. I am a techie with 8 yrs of experience in developing software products. if interested, shoot me an email.

<comment><AUTHOR> You don't have your email listed.

<comment><USER6> email@example.com</comment></comment></comment>


Germany Says No Bailouts for Deutsche Bank or Any Other Struggling Lenders - <AUTHOR> http://fortune.com/2016/09/29/deutsche-bank-germany-bailout/ <comment><USER2> While I understand why have Deutsche Bank fail could be a huge issue, I also believe it's necessary to show that banks are responsible for their own bad decisions.

In at least the US and Denmark we have the concept of systemically important banks. Bank that are to big to fail. These banks will, currently always be bailed out by the tax payers. So far it seems to have worked out for the benefit of the tax payers, because the governments have managed to make money on bailing out these banks.

What I however don't understand is why governments allow "to big to fail" banks to exist. The Danish government have actively encouraged people to choose bigger banks, arguing that there are to many banks in the country. It seems like what they should do is break up banks that are large enough to harm the nations economy, should they fail.

<comment><USER3> In this case it's messy because DB problems are caused by a US government fine, a fine that realistically they wouldn't have imposed on a major US bank. So it's less about individual bank performance but rather international politics and trade barriers.

<comment><USER4> "In a similar case, rival Goldman Sachs agreed in April to pay $5.06 billion to settle claims that it misled mortgage bond investors during the financial crisis." [1]

I don't know why the fine is lower, but it's the same order of magnitude...

[1] [https://www.theguardian.com/business/2016/sep/16/deutsche- ba...](https://www.theguardian.com/business/2016/sep/16/deutsche-bank-must- pay-14bn-fine-to-settle-us-mortgage-case)

<comment><USER5> Thanks for the link,

though isn't it 5,1x10e0 vs 1,4x10e1 and doesn't that mean it's not the same order of magnitude (I might misunderstand the concept)?

<comment><USER6> Are they different by a factor of 10 or more? If not, then they're within an order of magnitude (base-10).

<comment><USER4> Thanks, this is my definition too!

</comment></comment></comment></comment></comment></comment><comment><USER7> I'm all for wiping out bank shareholders to zero and sending corrupt executives to jail... but if the financial system and the public lose confidence in Deutsche Bank, one of the world's largest banks, we could end up with another global financial panic like the one we saw in 2008.

By many accounts, the second leg of the Great Depression of the 1930's started with the failure of an Austrian bank, Creditanstalt, in 1931, triggering financial panic and a wave of bank failures that ultimately affected everyone. See [https://en.wikipedia.org/wiki/Creditanstalt#First_Republic](https://en.wikipedia.org/wiki/Creditanstalt#First_Republic) , [http://www.bloomberg.com/news/articles/2011-04-20/lessons- fr...](http://www.bloomberg.com/news/articles/2011-04-20/lessons-from-the- credit-anstalt-collapse) and [http://www.cambridge.org/catalogue/catalogue.asp?isbn=052103...](http://www.cambridge.org/catalogue/catalogue.asp?isbn=0521030293) , for example.

The world cannot afford to have another global financial panic. The outcome could be catastrophic. Lenders, including depositors like your Aunt Tilly and Jack the plumber, should not have to worry about the safety and liquidity of their money.

The financial system is _infrastructure_ \-- like the electricity grid and the Internet. We cannot afford to have this infrastructure come to a halt due to the fear or stupidity of greedy executives. Businesses and consumers depend on this infrastructure every day.

<comment><USER8> So how about we bail out the institutions and throw the executives in jail? That seems like a good compromise.

<comment><USER9> Amen. Bringing accountability in the banking sector? That's a refreshing thought and a decisive step forward to save, whatever can be saved from the EU.

</comment></comment></comment><comment><USER10> This might be a silly question, but as a customer of Deutsche Bank what would the likely outcome be to your money and account if the bank is allowed to fail? Is it just that another bank takes over the account?

<comment><USER11> You lose all of the money over the amount that isn't insured. If the bank even has insurance.

<comment><USER2> What I find interesting is that you lose all money over the insurance amount, but you're guaranteed that someone will buy up any debt you may have, regardless of the amount. While I understand why that is, it hardly seems fair that the customers can only lose money.

<comment><USER12> Its working as designed. "Fair" was never part of the plan...

<comment><USER13> Yes, a bank is a business not a charity. Customer service is important but saving their own skin appears to matter more.

</comment></comment></comment></comment></comment><comment><USER14> The challenge in 2008 with the Lehman collapse and AIG's later struggles is that there was no method to wind down non-bank financial institutions except through the bankruptcy courts.

After the financial crisis regulators were given authority to take over non- bank financial institutions and also created the concept of bail-in where a large bank or financial institution that was in financial trouble could raise equity over night through forced conversion of some of its bonds to equity. This would of course dilute existing shareholders and result in potential losses for bond holders but the bank continues to function which removes the systematic risk. As part of the reform the banks were also required to hold more liquid capital to reduce the risk of runs and to go through stress tests to validate that bail-in capital was adequate.

The politics are that in Italy the banks bonds that would be subject to bail- in are held mostly be retail investors (granny and grandpa) and a bail in would be politically costly and they want to bailout banks using tax-payer funds.

At the end of the day losses due to bad loans have to be allocated. Those losses can be allocated to bank equity and bond holders through bail-in; depositors through bail-in or lower interest rates; tax holders through bail- outs; or to savers through Central Bank inflation and fiscal stimulus. Each one of those scenarios creates winners and losers with vested interests. There is also strong cultural memory with Germany looking back to the hyperinflation of the 30's that gave rise to the Nazi Party and the US looking back to the 30's and the Great Depression when losses were allocated to banks and depositors.

The alternative is extend and pretend which is to ignore bad debt and because in the future "we're all dead." This was used in Japan after its financial crisis and creates and interlocking group of zombie companies and banks which seem to feed on the rising generation.

Pick your poison I guess.

</comment><comment><USER15> It is important to remember that the reason many countries are out our cash/ deep in debt is because so much money has been spent on bailing out banks. E.g. in the UK, this was more than a trillion pounds at the peak of the crisis.

[https://www.theguardian.com/news/datablog/2011/nov/12/bank-b...](https://www.theguardian.com/news/datablog/2011/nov/12/bank- bailouts-uk-credit-crunch)

</comment><comment><USER16> We should all learn from how Iceland did it. Take the power back.

<comment><USER17> Icelander here. The popular story is very inaccurate.

However: I encourage everyone to do like the popular story of how Iceland says we did :)

<comment><USER16> Please explain, or link to an article that you believe show the more accurate story.

For all I know: Iceland let its banks fail and jailed some high-ups in said banks, while bankers worldwide said Iceland was going to have an endless recession because of it, which did not happen.

<comment><USER17> Please link to a story which you based your original words on so I may try to offer a POV which seems more correct seen from the ground here?

<comment><USER18> Don't know what the original commenter had in mind, but the vague, popular impression seems to be, in so many words:

 _" The brave people of Iceland decided they had enough, and formed a lynch mob and put a few dozen perpetrators in a real, actual jail. Which didn't reverse the damage caused, by any stretch, but at least they got sliver of self respect back after being taken for a ride by these assholes."_

Not sure how accurate that is, but any qualification (or just any articles at all you feel give a more grounded summary of events) would be very helpful.

</comment></comment></comment></comment></comment><comment><USER19> "Germany Says No Bailouts for Deutsche Bank"

These are basically the famous last words before any bank goes bankrupt and consistently get's a government bailout in Europe.

<comment><USER20> And this time the taxpayer will have the privilege of paying a fine levied for improper behaviour. Absurd.

</comment></comment><comment><USER21> While Germany might not step up now, the ECB will not let DB fail, it would send a shock wave through the euro block that can cause it to implode.

This is especially important now when countries like Poland have the Euro hanging over their heads.

<comment><USER22> Germany, imho, is doing whatever it can to avoid to put money in a failing institution because they promoted so much the "be responsible, no buyouts" in the whole EU area. Now that they are in trouble if they go for a buyout there will be _a_lot_ of states who will ask to definitely stop all the austerity measures they so hard promoted [and that, honestly, never worked for any south-west country in EU, they just worsen the situation].

<comment><USER9> No. That was the case for Greeks and PIIGS in general.

The Greek bailout, was an indirect bailout of Franco-German banks[1]. Ms Merkel was not able to ask for a second bailout, so she masked the bailout as a _solidarity_ towards Greeks.

Of course Greece's public debt sky-rocketed (from 120% of the GDP to 180% in 6 years) but the worst part was the total disintegration of the Greek economy. Since, throwing money in failed banks never works, we're back in square one. Oh, in the process she also destroyed the Eurozone, but that's just a side effect.

[1] [http://www.keeptalkinggreece.com/2016/05/04/german-esmt- stud...](http://www.keeptalkinggreece.com/2016/05/04/german-esmt-study-5-of- bailout-money-went-to-greeces-state-people-95-went-to-european-banks/)

<comment><USER19> Exactly this. We already saved DB in 2010, and by we, I mean, southern Europe and Irish taxpayers. It's well documented that the bulk of the debt contracted by southern European and Irish governments ended up mainly in DB and to a lesser part in the Bank of Scotland backed by the money of German taxpayers.

It's no wonder that Schauble was pressing so hard 2 years ago for a big part of Greek Assets to be held abroad as guarantee the debt payments would be made... where? In DB non the less.

</comment></comment></comment></comment><comment><USER23> Says who? - "a senior lawmaker in Chancellor Angela Merkel's conservative bloc". Germany will do what it has to do to keep its economy afloat. If they have to bail out their banks, my bet is they will.

<comment><USER24> Michelbach is not even well-known, actually.

</comment></comment><comment><USER25> Its worth pointing out banks in the EU haven't yet deleveraged like the banks in the UK and US. Deutsche bank falls under this list of being too leveraged.

</comment><comment><USER20> The only meaning of such a statement is to say that DB is in deep trouble.

It's just like when there's a big company meeting and the boss tells everyone you're going through hard times but everyone's job is safe. Or that the last round of redundancies was the final one.

Whether the government does bail them out can only be tested in one way.

</comment><comment><USER26> It could be an attempt to put pressure on the U.S. to reduce the fine. I'm sure DB _will_ be bailed out if the situation is there.</comment>


LogP: Towards a Realistic Model of Parallel Computation (1993) [pdf] - <AUTHOR> https://people.eecs.berkeley.edu/~kubitron/cs258/handouts/papers/logp.pdf <comment><USER2> LogP was based mostly on experiences in analyzing and working with parallel machines in the 1990s, best summarized in Culler, Singh, and Gupta's book "Parallel Computer Architecture: A Hardware/Software Approach". The model was based upon lessons learned from trying to build fast message layers for those machines. The influence was mostly aimed at the software layers of those machines, which led to Active Messages, U-Net, and related low-overhead messaging layers; less influential upon architectures, I would think.

</comment><comment><USER3> Seems similar to the Cell architecture of PS3 (if you look at how all the "Synergistic Processor Elements" are networked together via a bus). I wonder whether it was based on this?

<comment><AUTHOR> LogP is a general-purpose adaptive parallel model so not tied to a specific architecture. However, I too am curious if anyone knows the Cell lineage and if there is a connection. A cursory search on Google Scholar [1] shows the LogP paper is cited more than 2000 times, but I did not see a direct lineage reference between the IBM Cell architecture [2] and the Berkeley LogP model [3]. Does anyone know the history and if there is a connection?

[1] [https://scholar.google.com/scholar?cluster=52811921455145789...](https://scholar.google.com/scholar?cluster=5281192145514578941&hl=en&as_sdt=0,44&sciodt=0,44)

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

[3] [https://en.wikipedia.org/wiki/LogP_machine](https://en.wikipedia.org/wiki/LogP_machine)</comment></comment>