skysight-inc/HackerNews huggingface dataset:
A category is a collection of objects with a notion of morphism between said objects. Morphisms are really not defined much beyond that; it is all left rather abstract, though there are some basic laws that must be satisfied.

Categories are relatively uninteresting without functors. Functors are more or less mappings or transformations between categories.

Category theory by some accounts initiated in the foundations of algebraic topology. In that subject, one wishes to codify some of the aspects of a high-dimensional shape or geometric object in algebraic terms. The hope is that the algebraic image of the shape is easier to understand than the shape itself. The mapping of shapes into their algebraic "shadows" is a functor.

For instance, you can take a torus and look at the collection of all closed loops drawn on the surface of the torus. Now identify two loops as the same if one can be smoothly deformed into the other by moving it along the surface of the torus. Long story short, this gives the set of such loops a structure known as a group. There is a very extensive theory developed around groups, so you might surmise that you could partially classify shapes by looking at this associated group (called the fundamental group or first homotopy group).

This mapping from geometric objects to groups of loops drawn on them is a functor from the category of topological spaces to the category of groups. This is the beginning of homotopy theory.

As for your comment on sets, there is the category Set which consists of all sets. That is, the objects of Set are sets and, given two sets X and Y, the morphisms between X and Y in Set are simply the functions f : X -> Y. An interesting technical point here (which is related to your quote) is that Set itself cannot be a set, as there is no set of all sets within Zermelo-Fraenkel set theory (the most common axiomatic formulation of set theory). Rather, there is a notion of class, and one says that the collection of all sets forms a class rather than a set.
Ask HN: What do you use to write requirements/specs?
Currently I use a combination of Word, Excel and Visio to create requirement or spec docs. While it ultimately gets the job done, there has to be something better out there.

What do you use? Interested in free, open source and paid solutions.
Your site looks nice.

But one thing. Your target market is "coaches and players"

Yet your "about" page is targeted toward either a) getting funded or b) people who are into tech, read HN, etc.

That's a problem. You start of with "Andrew Reifman" who is a "pixel perfectionist". This has nothing to do with anything that your target market (say the coach at my local high school team) would even remotely care about.

The one person "Darren Pottinger" who has some street cred is listed as number two.

I think Darren should be the prominent person on that "about" page with the rest of the team deprecated (smaller type) or even placed on a separate page. Perhaps get some "advisors" that are coaches, players or other users to fill space on that page as well. Give it some meat.

That page to me says "we are looking to build a company" not "we have the expertise to help players and coaches with our product".

If someone wants to invest - your team will matter. But it shouldn't be presented in a way that detracts from the product or service you are offering.
"The theory basically goes that any civilisation which could evolve to a 'post-human' stage would almost certainly learn to run simulations on the scale of a universe. And that given the size of reality - billions of worlds, around billions of suns - it is fairly likely that if this is possible, it has already happened."

That sounds distinctly like Anselm's ontological proof for the existence of God, and thus likely suffers from the same logical fallacies.
R&D spending: when you are in a race to the bottom, you can only afford to invest in safe designs, and most of your focus is on efficiency. In contrast, Apple can afford lots of R&D spending.
FISMA Reform Passes House on 416-0 Vote
EFF Politely Asks PTO to Stop Issuing So Many Crappy Software Patents
The differential equations videos have been up since 2009.
They're stuck in a local optimum. These companies have to be structured in a certain way to succeed at low margin, high volume commodity hardware sales. It isn't easy to adapt that to higher-end products, and when they try the market is slow to recognize changes in a brand, which discourages them from trying.
Judging from what I see here, most applicants sent in a landing page? Or was there more to it - any demos?
The Inside Story: Men’s rights group causes controversy at U of T (news report)
>"Essentially, Savage said that computers used to build simulations perform "lattice quantum chromodynamics calculations" - dividing space into a four-dimensional grid."

I thought current quantum physics determined the universe had 13 dimensions? (two time version of M-theory)
Interviewstreet was rejected twice before applying the third time to get an email asking them to come in for a 10 min interview.
If by "outreach and encouragement" you mean outright subsidizing the trip for a specific target gender.

Did this actually improve the technical content of the conference, or did it simply redefine the objective measure by which PyCon determines "success" to include non-technical metrics? The latter seems to be the case, in which case, it's not a particularly valuable stratagem for a merit-focused technical conference.
It's even worse than that, because the example being used to condemn cost/benefit analysis actually reinforces it.

If you have a 1% chance of destroying the world, you're pretty much going to want to avoid taking that chance in almost every case according to a cost/benefit analysis, since 1% times the trillion trillion dollars that the world is worth to us will end up being more valuable than any alternative. The exception is when the next best alternative is even worse, i.e. a much higher probability of something only slightly less catastrophic.

On the other hand, suppose the calculated probability is not 1%. Suppose the alleged world-ending calamity is that the Flying Spaghetti Monster is going to be displeased and set fire to all of reality if you don't pay me a billion dollars. The probability of that actually happening is not 1%. It isn't 1% of 1%. It's close to, but not exactly, 0%. Is the argument that you should still pay me a billion dollars? After all, the risk if you don't is that the world will end. I accept payment as cashier's checks or wire transfer.
Hi.

Thanks a lot for your direct question.

For now there isn't a specific problem we are addressing - as you said, the product is more of my interpretation of easy-to-use project management software.

I am hoping with a good marketing analysis (and with the help of a marketing and sales professional), we can find some customers who prefer Collaborade over Basecamp...
Number of times I have stopped for gas on a 30-mile stretch of local toll road: 0.

Why would someone stop, just to get an excuse to speed later, at the same average? The few people drag-racing, maybe. Not the vast majority who want to to arrive at destination ASASP.

You are conjuring up a ridiculous hypothetical and claiming it is the common case.
That and the Finely Tuned Universe Paradox (the Goldilocks Enigma) is why I can't easily consider myself an atheist. I mean, chances are, this universe is "intelligently designed", in the most literal sense. I call it the "Alien God Hypothesis". It's probable that a race of aliens has mastered the "world creation mechanism", either by simulation or by physical hacking (who knows, maybe they can control black holes and create baby universes inside with just the right conditions for life).

At some point down the line there must be a purely physical universe though, but we're probably not there, but in one of the branches. So while I am not atheist in a pure sense, I am not a theist either. Nice, isn't it? Science makes almost full circle to religion. The IDers are almost right.
Why would "saving" be valued, metaphysically?
Quantum mechanics certaninly leads to a very informatic view of the Universe...

The problem is that this is human bias. You can describe any theory by information manipulation, and it is as good a description as any other.
Out of curiosity, what is everyone's preferred login mechanism?

Facebook? Twitter? Google?
The point is, to determine whether "this" universe is a simulation or not, you would need to look after a special characteristic that differentiates it from a "parent" universe.

If you prove the universe is computable, that still doesn't give you any answer whether it's a simulation or not.

As it stands, the theory is a tautology, because that's just proving the universe is something that it is.
I can say from personal experience that Apple started losing people the moment they released the App Store but refused to allow employees to participate. They created an incredibly exciting platform for development and then locked their best people out of it. No wonder some of them left.

The problem is now magnified because today there is much more uncertainty in regards to Apple's future. Jobs is gone, Forstall is being moved out with no obvious successor, Google/Android is taking the lead, the stock price is stagnating, iOS is losing its edge, PC sales (including Apple's) are slowing ... it looks like it could be the beginning of another "beleaguered" era soon. Who would want to stick around for that?
"GC and/or Automatic Reference Counting at compile time" - What do you mean by that?
If it is a simulation, it must be running on a Solaris server sitting in the corner of some office, boasting a record uptime.
Reminded me of an excerpt of "La Révolution des fourmis" ("The Revolution of the Ants", 1996) by the french writer Bernard Werber, in which students run such a simulation (named InfraWorld), until "simulated scientists" uncover the truth of their condition, leading to mass hysteria and eventually the collapse of their civilization...
No. That was not a war.
If you want to take on a non-strawman version of the argument, check out benhammer's links below.

That said, I do often feel that at the literal edges of our universe (in all the senses of that term), our uncertainties simply dominate everything and all of our guesses about the true nature of reality are dominated by that uncertainty. Something (or, depending, multiple somethings) must be true for some value of true, but I'm skeptical if we can discover it. If it popped up and simply flat-out told us what the truth was somehow (the Great Simulator writing the message in the stars [1]), we probably couldn't confirm it.

[1]: http://lesswrong.com/lw/qk/that_alien_message/
You might be interested to learn that radio waves can travel well in excess in of 90mph. as can helicopters. In fact, many jurisdictions ban high-speed chases, specifically because they are more dangerous than they help.
The cynic in me wonders if the "deal" is with a rich family member to give her a ton of free press.
Why would they put up with being screamed at? Is the glamor of working at Apple worth it?
Welcome to the magical world of link bait, where "yeah it happens" and two mysterious sources who are probably totally legit, 4rz honestly totes legit are enough for DEATH OF APPLE-NETCRAFT CONFIRMS IT headlines to start circulating.

If it bleeds, it leads.
I'm just complaining, but it feels like Lenovo is busy pissing off all the loyal ThinkPad users. Each iteration takes ThinkPad one step closer to shiny crap laptop, like a Dell or HP. And they still can't get decent resolution screens, even on 14" models. Some of the newer stuff looks neat (like the Helix), but has nerfed hardware, like 8GB RAM max.

I don't even really care about "ultra" book. The old X-series ThinkPads were great. 12", a few pounds, portable enough. They killed that line by switching to a crap consumer screen.

I wonder if the laptop market will go to hell and the shiny factor won't be an issue cause consumers will be buying other things. At that point, perhaps laptop companies will once again focus on people willing to spend a lot on good hardware.
I wonder if the civilization creating the simulation would have motivations beyond just doing this because they can. Perhaps with the benefits of a vastly accelerated timescale a simulation could be used for predictive purposes.

As for simulations within simulations. If we are in a simulation and our "program" is permitted to run long enough by it's creators we will most certainly find out :)
No, it doesn't really work that way. A wavefunction is based upon a configuration space and you can't just neglect part of it or you'll get inaccurate results.
Love that you have a functional page and not another one of the launchrock sites I had to click through.

One alumni told me that YC was all about picking billion dollar, not million dollar businesses. In that case, could you say juniper would scale to the billion dollar market? Could your users track their usage with a recurring Google calendar entry? (I know women that do). Why not scale to include other high usage products - toothpaste, toilet paper, etc? (I know of one startup in stealth mode doing this, so it's probably a feasible plan). Sorry for playing devil's advocate - really like what you got so far though.
It's just my opinion, but I believe the scope has been mistaken. People have had a tendency to miss on scale throughout history in regards to both the micro and macro spheres.

What we call the universe today, I believe there may be a trillion of them (connected in the same way that galaxies are). They're so large and so far apart, we still don't realize it yet. I believe we've missed on the macro scale just like we did on the micro scale in discovering the tiny world of atoms etc. I believe we'll figure this out in the next hundred years as our optics and data gathering become far more advanced.

In this scenario, if there are just 10 civilizations per 'universe' - there would still be billions or trillions of civilizations, and they would almost never meet due to the extreme scale involved (by the time you could attempt to explore your universe, it has already begun killing you off by imploding).
He was something of a super speeder, check out his lap times:

http://www.sun-sentinel.com/news/local/speeding-cops/fl-gx-f...

120 MPH was almost double the speed limit (65 MPH) and as the data shows it was a routine. The data shows only average times, so who knows what his top speed was (he was "only" averaging 95 the day he got busted for going 120).

He was very frequently averaging speeds that constitute reckless driving. He's lucky he just got fired, his license should be suspended for a long period of time just like it would be for anyone else that wasn't a cop.
Yes, you are correct. However if an app had ads and was also Free (libre), it could be recompiled and redistributed without ads too. What I meant to convey was that these apps are all GPL, MIT, BSD, etc licensed, and also wanted to convey that they respect you (by not spying on you, or burning your battery/bandwidth serving ads, etc), and are otherwise most likely RMS approved :-). I should have been more clear that they are both types of free.
Hmm no, if there is inflation, enact a one time wealth tax and then cancel those money.

Also, you can print money to increase supply, this is what the Asian miracle is all about after all. Too bad they didn't print money to increase demand...
So, if we can't meet aliens to chat, we can create our own. We just need to simulate their universe.
In a galaxy far, far away.

My guess is that there are other civilizations out there, but they're suffering from the exact same problems as us - long distances, huge energy requirements, lots of time. If we can't get out to the stars, I can see why plenty of civilizations would be having trouble.
Oh, I thought you were going to mention http://sivers.org/1pct

Sad that Cheney was the most famous and morbid believes in the 1-percent fallacy.
OP here. I'm sensing some generalized anti-police sentiment. Many cities allow residents to "ride along" in a police car for a shift. (In the front!) It's not a bad thing to do.
I will try not to be surprised when most of the money raised is spent on the salaries of the promoters.

This comment fulfills your RDA of cynical first comments on HN.
Node.js & WebSocket - Simple chat tutorial
We use mediawiki, and each client gets their own wiki site.

I set them up so the client only had read access to the main content, buy has write access to the talk pages.

This allows us to publish version controlled specs, with closely tied discussions (on the talk page) for each spec.

The biggest problem with this though is getting the clients to edit the talk page correctly.
I love this tradition; and for the first time would like to make a similar offer:

Anyone who got rejected from YC S13 forward your rejection email to freewine@undergroundcellar.com and I'll send you a $25 gift card for free wine from http://UndergroundCellar.com

I'm not suggesting you drink your problems away, but a relaxing glass of wine can be a nice way to wind down before you get back to those 14 hour hack days.
Thanks a lot, there is actually a bug in the currency detection code.

Yes, you are right - probably the homepage needs some re-thinking.
I read "ultrabook" as "any high-end laptop not made by apple".
Mostly it's people who play politics at large co get's the big bucks. The real stars leave to start their own company or consult.
>Why would someone stop, just to get an excuse to speed later, at the same average?

You do understand that there are service plazas on toll roads. People stop for gas because they need gas, not because they want to speed. But once someone has stopped, or intends to stop before the toll booth, they're no longer subject to the timer and end up creating a dangerous speed differential against the drivers who are.
First off: why would you assume that we could interact with them?

It appears to be phenomenally difficult to get from point to point in the galaxy/universe (see the recent trend in science-fiction to stick to a speed of light limited universe). If we come up with some fantastic energy source (see: ZPE), then I'll say that it's phenomenally slow so that no civilization would invest in doing it. If we come up with some civilization that would do so, I'd point out that it's phenomenally slow/difficult to send signals across universal distances. Rational folks think that non-solar-local interactions are probably not possible... Large brained rational folks think to look for solar-local artifacts of Kardashev-scale>1 civilizations (see: http://www.personal.psu.edu/jtw13/blogs/astrowright/2013/03/...).

Recall that early explorers met Native Americans and called them Indians because they had misinterpreted distances, didn't know all of the continents, etc. We have a history of overcoming increasingly large distances with improved transport. This does not mean that we shall always do so.

It may be depressing, but it may be the case that exponential curves in natural do not exist. We may live in a time where we understand that sigmoids rule the evolution of our world/civilizations...

(And no the plural of Malthus is not proof of an exponential curves in nature...)
number of times you've not stopped for gas which are relevant: 0

the point is that if you intend to stop, or must stop, you are free to speed without fear of automatic ticketing.
Palabras Bonitas Para Mi Novio - Secretos
> As opposed to us simply being some other civilization on one of the other billions of habitable planets in that same "first" universe?

Yes, but if we are in a simulation we can almost answer the Fine-tuned Universe Paradox too, two birds with one stone. That is nice for Occam's rasor reasons.
huffingtonpost. fortellers of scientific breakthrough?

You decide.
It's true - the majority of crime and unprovoked acts of violence in many regions are committed by law enforcement and the legal system as a whole.

The solution is to replace the current feudal legal system with a framework that seeks to reduce violence.
If you work on Windows and want something with full vector graphic drawing, take a look at Xara Designer Pro or Xara Web Designer Premium. You'll have drawing capabilities like with Illustrator, but it's faster and you can assign things as buttons and mockup working websites.

You can make working dropdown menus too.

It produces a lot of absolute positioned css code, so it's not integrated with any web framework but does render pixel perfect.

I'm not sure how it would handle a responsive site, probably not, but you could quickly mockup the mobile version though.

You might also look at Corel Draw too.

If you want free, again Pencil, Inkscape or try the Google Draw templates - http://mortenjust.com/2010/04/19/a-wireframe-kit-for-google-...

another recommend for draw.io and also look the maqueta software - http://maqetta.org/news/2011/ibm-contributes-maqetta-html5-v...
Wonderful, I'll be checking this blog regularly.
Well, the Retina MacBook Pro very nearly fits your profile. The fans are whisper-quiet, and the screen is beautiful.

I'm a ThinkPad die-hard, but somehow Lenovo is managing to destroy every last bit of the legacy IBM worked so hard to build, so, sadly, I'm typing this from a 13" MacBook Air.

I couldn't bring myself to buy a cheapened fiberglass budget laptop after my lovely T60p.
I have often thought that if 20th century science tried to ram home the logical necessity of atheism, 21st century science rams home the logical necessity of agnosticism being the ground level, so to speak. If we, tiny as we still are, can even conceive of a practical way to simulate a universe (and what is truly the difference between "simulate" and "create" in the end?), how can we in good conscience fully rule out the idea that we are in fact in a simulation, and that whoever it is that is simulating us is in every reasonable sense a lower-case-d deity? They may be leaving us alone, ignorant of our existence (perhaps they only care about the large-scale results and we are but a blip), etc etc the entire well explored set of possible philosophical deities, but how can we confidently proclaim that none of them exist?

In the 20th century, one could be ignorant and scoff at the idea that Mankind might ever create a universe, and therefore scoff by extension at the idea that anyone or anything else could either... but now we know better. We've got universe prototypes already in production as ongoing commercial concerns (far more than mere theory!), at various stages of incredible primitiveness, but prototypes nonetheless. Rather than a massive leap, it is now merely logical progression that something, somewhere in some reality may actually have the knowledge and the resources to have "created" our universe, for some value of the term "created".

(I speak here of science in the vague philosophical movement sense. As much as it would like to claim total philosophical neutrality, there are certain Opinions that are Had.)
> The so-called meritocracy you think exists does not. Its just structural discrimination of a different stripe.

What does this have to do with evaluating papers? Why would we divert ourselves from a technical mission to pick up an unrelated social cause?

> The so-called meritocracy you think exists does not. Its just structural discrimination of a different stripe.

The place to worry about correcting structural discrimination isn't at the point where it's already happened. That correction would be artificial and as such, detrimental to furtherance of our art and science.

The time to correct structural discrimination is long before anyone is submitting papers to present research they've already done.
Yeah, dude. What do you think the Big Bang was?
How Damaged Are NFL Players' Brains?
Health effects of wine
FWIW, Obama and Romney have both lived abroad. I think it takes a certain kind of person to want to be president, and the effect of travel is different on a person like that.

For this and other reasons, I think electoral politics is one of the least effective places to put energy, in working for change.