Ask HN: Good/Bad Comment Qualities? - <AUTHOR>

With all this talk about the decline in comment quality lately on HN, I thought it would be helpful to collect some data on what people think the specific qualities are of good/bad comments.
Here's what I'm looking for:
1. Positive and negative qualities are both useful (but neutral is meh, don't bother).
2. Ranking your qualities would be very helpful but optional. (1. helpful, 2. organized, 3. etc...)
3. Explaining your choices is appreciated (and will keep things interesting).
4. Everyone doesn't need to agree, in fact, I am more interested in the differences for my analysis (variety is good).
5. Bonus points for meta comments that have the qualities they list. (meta)
I'll tally up votes for comments too but it'll have to wait till pg reverts the system back or passes along the data some other way. Hopefully this data will be useful for making HN even better.
Thanks for everyone's help! <comment><USER2> <joke> Good: comments I agree with. Bad: comments I disagree with. </joke>

And if I left it there, I'd rate my own comment poorly (#2, below). So, now I'll try to be serious:

1\. Comments I consider to be high value tend to reference external sources (other websites or authorities), which tends to create a minimal sort of empirical grounding. External links that add information to a topic are valuable. I.e., new information usually == good.

2\. One liners, quips, etc... tend to be low value.

3\. Many other values are subjective. Clear, punchy writing adds value, as does insightful analysis, but what counts as "clear" or "insightful" varies by the reader.

4\. I personally have a bias towards ideas that are new to me; at least then, I feel I've learned something. But again, new != good, necessarily.

5\. IMHO, the worst sorts of comments cluster in the most controversial sorts of threads. E.g., anything political or mired in non empirical sorts of value judgments[1]. See PG's essay "Keep Your Identity Small": <http://www.paulgraham.com/identity.html>. If I were to wager, I'd bet that the reason comment quality has been perceived to decline is mostly a function of the increased number of such threads.

[1] I personally find these interesting, because I enjoy debating philosophy & politics. But I'm also guessing that these things aren't so highly valued here.</comment>


How do you balance having a gf with running a business? - <AUTHOR> Gf's take up a lot of time and often money, so how do you folks balance it? Please share. <comment><USER2> It's a choice. You can choose to spend time with someone you love and hopefully want to spend the rest of your life with or you can choose to spend time on your business. Think carefully about this decision. One will leave you with someone to hold your hand on your deathbed, with countless beautiful memories and, heck, maybe even children. The other, if you're lucky, will leave you with buckets and buckets of money. One of these sets of things is more important than the other. Hopefully you still know which is which.

<comment><USER3> I recall reading an article (was linked from HN some time back) about people nearing the end of their lives. Nobody wished they had spent more time at work.

Startup culture focuses too much on money and fails to look at the many beautiful, important things that money cannot buy.

Contrary to the aphorism; he who dies with the most toys / money didn't win. He missed out on living a life to the fullest potential.

<comment><USER2> Totally agree about startup culture.

</comment></comment></comment><comment><USER4> Most of the time you don't. It's a cliche - but true - that trying to do a startup or run a time intensive business, is a relationship killer.

The money side of it, if it's someone that is really in to you, is not a big deal compared to the time.

You only get to choose to invest in to a few things time wise, when you're doing a startup. You can watch TV, or exercise. You can play video games, or eat healthier by cooking every meal. You get the idea. In my opinion, the best way to keep a gf during this time, is to abandon anything else that is worth less to you in life than her (except the critical stuff like health related items).

Don't watch tv, watch movies, or play games, unless it's with her. If you can, work out with her; cook, with her. Do the startup, and spend time with her, and that's your life.

Otherwise, until things settle down, don't date unless you're ok with casual dating or dealing with upset girlfriends.

</comment><comment><USER3> I think you meant to write ___needy_ __GFs take up a lot of time and money.

If you are consistently working more than 60 hours/week, then maybe you need to learn to delegate. Working 100 hrs/week only leads to burn out. With or without a GF you will suffer health problems. So having GF with whom to share non-working time and "exercise" (ahem) is good for you. If you don't feel invigorated after spending a couple of hours with her, then maybe it's an inter-personal dynamic issue - time to move on.

In my experience there are many entrepreneurial / career-oriented women out there who work hard and play hard. Believe it or not, they often complain they can't find men who can understand them ... so there's your chance.

As for the money. You probably don't choose to be a sugar daddy - so stop dating gold diggers.

</comment><comment><USER5> Get/Keep your girl involved in your business.

Your girl might view your business as something to compete with for your time because she sees it as an unknown black box. The way to fix this is to talk to her about your business (and your goals). The more she knows about what you do, the more likely she will understand why your business needs your time.

(I am assuming that you are in a serious relationship with your gf. If you are not there yet, then it is best not to mix your business & personal relationships)

</comment><comment><USER6> Marry her!

</comment><comment><USER7> In any relationship, it's important to set limits. If you don't, if you permit others to transgress your boundaries, you are likely to become the victim of domestic abuse.

In my particular case, I wish now that I'd put a lock on the door of my office. My now ex-wife was heavily into how I should make my cables somehow go away. She felt they were ugly. I regarded this as hurtful, I always wanted to point out to her that "My computer cables make my computers go. Without them I would be unemployed."

HOWEVER!

It is also important not to let your work run your life. That was another mistake I made; to the extent you possibly can, make time for her every single day. Take the weekends off.

Given the way things ultimately turned out, I regard it as being for the best that we are divorced. But there are many ways that things did not have to turn out that way.

To the extent that we worked together towards a common purpose, we got along really, really well. I did not realize that, not in a conscious way, until just recently.</comment>


JCPenney's Grading System For Employees - <AUTHOR> http://www.businessinsider.com/jcpenneys-grading-system-for-employees-2013-3 <comment><USER2> Looks like a simple triage to me. I don't see an issue unless they're making it publicly visible to your coworkers.</comment>


Rethinking the origins of the universe - <AUTHOR> http://unc.edu/spotlight/rethinking-the-origins-of-the-universe/ <comment><USER2> Quote: "Experimental evidence may one day provide physical proof as to whether or not black holes exist in the universe. But for now, Mersini-Houghton says the mathematics are conclusive."

Not as conclusive as the evidence for black holes. Remember that the article's hypothesis requires proof that black holes do not exist -- in other words, proof of a negative. Proof of a negative is generally regarded as an impossible evidentiary burden, and calls into doubt the hypothesis that relies on it.

There's pretty good evidence for very large, very dense masses at the center of most galaxies including our own. The default conclusion based on the evidence is that they're black holes -- they have the right mass and density.

We should all remember that a mathematical theory isn't a scientific theory until observation bears it out (produces positive evidence), and to the exclusion of competing explanations.

</comment><comment><USER3> This doesn't really mean anything, as the work isn't peer-reviewed yet. However, if this does become accepted it will have an extremely large impact in Physics. The fact that this could do away with the information paradox and add some harmony between General Relativity and Quantum Mechanics is a big deal. Furthermore, as the title suggests, we have to rethink the origins of our universe.

</comment><comment><USER4> I think that interested people should just read the abstract, introduction and conclusions of the actual paper: [http://arxiv.org/abs/arXiv:1409.1837](http://arxiv.org/abs/arXiv:1409.1837)

You will not understand the full implications of it (well, unless you are an astrophysicist), and I didn't bother with the meat of the paper (because I am also not an astrophysicist). But the abstract, introduction and conclusion are rather understandable, and far less hyperbolic than the press release. And even though I can't understand all of it, I'd much rather get a misunderstanding from the original source material, then get a compounded misunderstanding from a press-release.

</comment><comment><USER5> The article mentioned, "Mersini-Houghton shows that by giving off this radiation, the star also sheds mass. So much so that as it shrinks it no longer has the density to become a black hole."

If anyone else wondered how the radiation of massless particles could result in the reduction of mass, I've found a resource with simple explanations for a layperson like myself. [https://www.physicsforums.com/threads/mass-lost-by- the-sun-b...](https://www.physicsforums.com/threads/mass-lost-by-the-sun-by- emitting-radiation.708814/)

</comment><comment><USER6> Interesting; if the paper finds general acceptance, it'll be fun to watch a new flurry of activity. The fairly recent controversial concept of "firewalls" has reinvigorated that subfield of physics.

Whether black holes exist or not, there's something _really_ dense at the center of our galaxy. It's a challenge to come up with a consistent non-black- hole explanation for the observed motion of stars at the galactic center.

[http://www.galacticcenter.astro.ucla.edu/images/2011orbits_a...](http://www.galacticcenter.astro.ucla.edu/images/2011orbits_animfull.gif)

More here: [http://www.galacticcenter.astro.ucla.edu/journey/smbh.html](http://www.galacticcenter.astro.ucla.edu/journey/smbh.html)

<comment><USER7> This is why I love astrophysics (and the scientific method). When you find something conclusive (assuming the paper is accurate), and it causes you to re-think what you thought you knew about the universe, it suddenly becomes larger than you ever believed possible. I hope this paper is true - since it solves the information paradox.

</comment></comment><comment><USER8> _" from Star Trek to Hollywood"_

So... Hollywood? Star Trek wasn't filmed on location - Desilu and Paramount were both located in Hollywood.

Not that this, y'know, matters - just found it amusing.

<comment><USER9> Filming Star Trek on location would have been pretty difficult, I'd imagine.

<comment><USER10> Well San Francisco, Cape Canaveral, and New York City figure in various episodes and movies. (Just off the top of my head.)

</comment></comment></comment><comment><USER11> related tidbit:

[http://en.wikipedia.org/wiki/Black_hole#Evaporation](http://en.wikipedia.org/wiki/Black_hole#Evaporation)

"A stellar black hole of one solar mass has a Hawking temperature of about 100 nanokelvins. This is far less than the 2.7 K temperature of the cosmic microwave background radiation. Stellar-mass or larger black holes receive more mass from the cosmic microwave background than they emit through Hawking radiation and thus will grow instead of shrink. "

</comment><comment><USER12> This paper claims that black holes can't come into existence, which is subtly different from claiming that they cannot exist. In particular, black holes can exist as long as they've always existed – it's just that new ones can't come into existence. Maybe the universe just has a fixed number of singularities. [I am not a physicist – this just struck me as an inaccurate implication in the article.]

<comment><USER13> I agree that it seems as if the article is a bit overzealous as to the implications of this work (claiming singularities cannot exist, in particular the one from which the big bang expanded). But, your idea that something has "always existed" in a universe that hasn't "always existed" doesn't seem plausible.

The author's claim that the big bang theory is now invalid because of this calculation of energy loss of a collapsing star being too fast to result in a black hole seems incorrect to me. The singularity from which the universe expanded (according to the big bang) is sort of "untouchable" by physics at the moment. I would guess there are some of the string/brane theory models out there that postulate what caused the big bang but currently it is my understanding that whatever information was around about the cause of that singularity is not accessible to us. Again, who knows what we will discover in the future but as of now, making any bold assertion about the lack of existence of that initial singularity seems presumptuous.

<comment><USER14> You're experiencing cognitive bias.

If it is presumptuous to present calculations that may invalidate a _theory_ based on assumptions, then it is also presumptuous to disregard such calculations and state that the _theory_ itself is automagically correct, just because the assumptions are untouchable.

A bold assertion indeed.

</comment></comment></comment><comment><USER15> Well, there is are a lot of observational evidence for black holes - the by far most likely scenario is that the model they analyzed does not describe the physics of black holes in our universe.

<comment><USER16> This is the first question I thought of. I'm not a physicist so I dare say I can't interpret the paper but I'm curious how she explains the _seemingly_ observed orbits of stars around the black hole in the middle of our galaxy and others[1][2].

[1][http://astro.uchicago.edu/cosmus/projects/UCLA_GCG/](http://astro.uchicago.edu/cosmus/projects/UCLA_GCG/) [2][http://en.wikipedia.org/wiki/Accretion_disc](http://en.wikipedia.org/wiki/Accretion_disc)

</comment></comment><comment><USER17> I'm not at all acquainted with astrophysics but I remember seeing an article state that there was a different physicist who proved this same thing:

[https://news.ycombinator.com/item?id=7191324](https://news.ycombinator.com/item?id=7191324)

A quick google shows his response to this:

[https://twitter.com/abhasmitra/status/514804101024997376](https://twitter.com/abhasmitra/status/514804101024997376)

His response:

"Hawking radiation is unproven. And particle physicists are not aware that even without any Quantum Mechanics, classical gravitation dictates that all gravitational collapse must be accompanied by radiation. :

[http://link.aps.org/doi/10.1103/PhysRevD.74.024010](http://link.aps.org/doi/10.1103/PhysRevD.74.024010)

([http://arxiv.org/pdf/gr-qc/0605066v3.pdf](http://arxiv.org/pdf/gr- qc/0605066v3.pdf))

And then grav collapse should naturally lead to radiation supported ECO: [http://www.sciencedirect.com/science/article/pii/S1384107606...](http://www.sciencedirect.com/science/article/pii/S1384107606000923)

[http://mnras.oxfordjournals.org/content/369/1/492](http://mnras.oxfordjournals.org/content/369/1/492)

[http://mnrasl.oxfordjournals.org/content/404/1/L50](http://mnrasl.oxfordjournals.org/content/404/1/L50)

And as far as non -formation of ``Event Horizon'' is concerned, in contrast to the conjectures of the present yet unpublished paper I gave EXACT proof:

[http://www.ias.ac.in/pramana/v73/p615/fulltext.pdf](http://www.ias.ac.in/pramana/v73/p615/fulltext.pdf)

But phys.org never highlighted my research which is infinitely more accurate than the present paper whose authors are not even aware that Question of Hawking Radiation Would Arise Only If There Would Already Be a Black Hole With an Event Horizon. Therefore This paper is not self-consistent. But that does not matter:

The lead author of this paper has CAMBRIDGE AFFILIATION.

So phys.org is glad to highlight an inconsistent and yet unpublished paper by ignoring my series of my exact and original papers on the same topic."

I don't have any background in astrophysics, can anyone comment on Dr. Mitra's response and the relation of his work to the above research?

The best discussion I can find on Dr. Mitra's work is on quora: [https://www.quora.com/Is-it-true-that-Abhas-Mitra- resolved-t...](https://www.quora.com/Is-it-true-that-Abhas-Mitra-resolved-the- Black-Hole-paradox-13-years-before-Stephen-Hawking)

<comment><USER11> >But phys.org never highlighted my research which is infinitely more accurate than [...]

>The lead author of this paper has CAMBRIDGE AFFILIATION.

>So phys.org is glad to highlight an inconsistent and yet unpublished paper by ignoring my series of my exact and original papers on the same topic."

welcome to modern science. It is a professional guild like a guild of shoemakers of Middle Age Europe cities with about the same rules. Or like another my friend (former second-rate professor from a first rate university :) put it - it is a mafia, at every level. Researchers of the highest tier universities publish in the highest tier journals, researchers of the next tier - in the next tier journals, ... A good physicist should be able to understand the laws of Nature behind such formation :)

</comment></comment><comment><USER18> From the article:

"Laura Mersini-Houghton has mathematically proven that quantum effects are strong enough to stop the formation of black holes..."

If I'm not mistaken, Mersini-Houghton's work has just hit the scene. It still has to be vetted by the larger community before we could say that anything's been "proven."

<comment><USER2> Not to mention what I'm about to -- that scientific theories are never proven, only disproven. You can always tell when a journalist is speaking about a topic for which a scientist might be a better source.

As to "mathematically proven", it's an unfortunate juxtaposition of math (where things really can be conclusively proven) and physics (where they cannot be).

<comment><USER18> Right. I was going to mention that as well, but didn't want to be too knit picky :).

</comment></comment></comment><comment><USER19> What many people seem to overlook is that gravity is linked to time (space time)!

So instead of the "black hole" being massive, it could be that time is running fast!

<comment><USER20> Well, "linked" is vague. They aren't linked—they are the same thing! Gravity is an effect mass has on the upholstery of the universe. Time runs slower for us here inside the gravity well of Earth than it does for astronauts in zero gravity.

You can't create time distortions without gravity distortions, and you can't create gravity distortions without instantiating mass, so... big massive black holes have to be running slow; if they exist at all and aren't just cosmic bees sitting at the 2D boundary of the universe and projecting nothingness into our inflated space.

<comment><USER2> > They aren't linked—they are the same thing!

If you're speaking of time and space, no, they're different -- they're certainly all part of one spacetime, but they're distinct. This distinct:

t' = t √(1-v^2/c^2)

t = time

v = velocity

c = speed of light

t' = time at velocity v relative to velocity 0

Put into words, this special relativity relationship shows that an increase in velocity (movement in space) causes a reduction in time's rate of passing (movement in time). The general relativity version has more terms, and shows a relationship between mass and both space and time.

So space, time and mass aren't the same thing, but they're part of an interrelated system, one easily described mathematically.

> Time runs slower for us here inside the gravity well of Earth than it does > for astronauts in zero gravity.

Yes, true, but astronauts in orbit aren't in zero gravity, they're in free- fall. The gravitational force at typical orbital heights is nearly as strong as it is at the surface.

</comment></comment></comment><comment><USER21> "In 1974, Stephen Hawking used quantum mechanics to show that black holes emit radiation. Since then, scientists have detected fingerprints in the cosmos that are consistent with this radiation, identifying an ever-increasing list of the universe's black holes."

Er, what? I don't think this is true, or Hawking would have his Nobel prize by now. Maybe consistent in the sense that the predictions are that Hawking radiation is undetectably low for stellar mass black holes. Also, analogue systems don't count.

<comment><USER22> > "Stephen Hawking used quantum mechanics to show that black holes emit > radiation." I don't think this is true, or Hawking would have his Nobel > prize by now

Hawking not getting a Nobel by now doesn't mean much. Einstein never got one for relativity (either Special or General), and when he did get his Nobel he was told not to mention "relativity" in his speech.

<comment><USER23> Einstein guy his for his work with Brownian Motion. Nobel prizes aren't typically given for science that lacks a body of supporting evidence, which was the case at the time for Relativity.

</comment></comment></comment><comment><USER24> Just downloaded the PDF, I am not a physicien nor a mathematicien.

but from what I read in the article the EQ 13, is the weakness of their argumentation.

AA

<comment><USER24> Their boundery limit pose a problem, and then the entire solution in the extending (prior explosion) the radius is greater the rs, and so all the fellowing integral are wrong. but I will wait for Hawking opinion :)

</comment></comment><comment><USER25> Interesting to note that LIGO [http://www.ligo.caltech.edu](http://www.ligo.caltech.edu) never detected any gravity waves (supposedly created by colliding black holes). This is the NSF's most ambitious project and they have spent (still are spending) a butt load of money on it.

</comment><comment><USER11> Ok. To start she addresses only "Gravitationally Collapsing Star"s. Interesting result, may be many star lifecycles don't end in a black hole. The "before-black-hole" state she describes still would involve significant time dilation and thus what we see as Hawking radiation from black hole may just be Hawking radiation from "before-black-hole" star. Looks the same :)

The result doesn't say that black hole is impossible. It says that a star's collapse loses mass faster than acceptable for the collapse to end in black hole.

Some misconceptions in the web-post:

>They are the ultimate unknown – the blackest and most dense objects in the universe that do not even let light escape.

a black hole isn't necessary most dense. After all a black hole with a mass of visible Universe would be only 125 times denser than current average density of the visible Universe (i.e. 45B light years radius of visible Universe have 10B light years Schwarzschild radius)

> So the story went, an invisible membrane known as the event horizon > surrounds the singularity and crossing this horizon means that you could > never cross back. It's the point where a black hole's gravitational pull is > so strong that nothing can escape it.

"membrane" is very bad illustration. It is constantly changing solution to the gravitational equations. One moment it is here, another moment - it has moved because gravitation of black hole changes and a lot of oscillations/perturbations happen. One moment you're inside, another - outside.

"gravitational pull is so strong that nothing can escape it" \- that's bad wording too. It is actually "gravitational well is so deep that nothing can escape it". Feel the difference :) A huge black hole may have pretty weak gravitation at its horizon.

Thus no-escape is valid only in the sense that escaping object just would never reach "a point at infinity" from the black hole and the light would get red-shifted into full oblivion.

<comment><USER2> > A huge black hole may have pretty weak gravitation at its horizon.

Not really. The amount of spacetime curvature at the event horizon is fixed in the theory -- it's always the same. It's how the event horizon is defined. Near the event horizon, light orbits endlessly (in principle), and (again in principle) if you were located at an event horizon and there was sufficient illumination, anywhere you turned you would see the back of your own head.

> Thus no-escape is valid only in the sense that escaping object just would > never reach "a point at infinity" from the black hole and the light would > get red-shifted into full oblivion.

From a more distant frame of reference, yes, but not at the event horizon itself.

<comment><USER26> > The amount of spacetime curvature at the event horizon is fixed in the > theory -- it's always the same.

No, its greater the smaller the horizon is (so, equivalently, less the bigger the horizon is).

> Near the event horizon, light orbits endlessly (in principle)

Sure, at the event horizon, light orbits endlessly. But the amount of curvature needed to do that is less the further across the horizon is.

<comment><USER2> >> The amount of spacetime curvature at the event horizon is fixed in the theory -- it's always the same.

> No, its greater the smaller the horizon is (so, equivalently, less the > bigger the horizon is).

We're using different meanings of "curvature". For all black holes regardless of their properties, the event horizon has the same spacetime curvature -- that required to produce orbiting photons that cannot escape. Outside the event horizon, photons can escape. Inside, they cannot (and those photons don't orbit either, but cross the horizon). All the same.

> But the amount of curvature needed to do that is less the further across the > horizon is.

No, it's the same. Same curvature, different large-scale geometry. For a sufficiently small zone near the event horizon, the conditions are identical.

Again, this is about the meaning of "curvature". The circumference of the horizon is greater for a large mass than a small one, but the spacetime curvature at the horizon is the same -- it's the specific value that causes photons to orbit perpetually, and interestingly from a local perspective, the entire horizon surface appears as a plane of infinite extent, sort of like two facing mirrors but with more dimensions.

From the perspective of a hypothetical observer at the horizon, he wouldn't be able to judge the size of the black hole using local observations -- there would be a plane of infinite extent for any black hole regardless of size.

</comment></comment></comment></comment><comment><USER27> If I read the abstract and introduction correctly, it doesn't say that black holes per se don't exist, only that they can't form as the result of a collapsing star or supernova. The linked-to article seems to be jumping to conclusions (e.g., rethinking the origin of the universe; impossibility of black holes at all, etc.) that the paper isn't even making.

</comment><comment><USER28> Isn't there a lot of observational evidence for black holes ?

</comment><comment><USER29> If black holes don't exist, what are those massive things at the centers of galaxies?

<comment><USER30> They're complexity anomalies. Things can't resolve themselves out and so stay in.

</comment></comment><comment><USER16> Ethan Siegel just posted a detailed response to this.

[https://medium.com/starts-with-a-bang/yes-virginia-black- hol...](https://medium.com/starts-with-a-bang/yes-virginia-black-holes-exist- df0a131d7b95)

<comment><USER4> I don't think that is a response to this work. That is dated February 1. He links to this paper's author, Laura Mersini-Houghton, but he links to a paper and blog post of hers from January. Reading that blog post ([http://backreaction.blogspot.com/2014/01/if-it-quacks- like-b...](http://backreaction.blogspot.com/2014/01/if-it-quacks-like-black- hole.html)), what she says seems to be in contradiction with the more recent paper she wrote ([http://arxiv.org/abs/arXiv:1409.1837](http://arxiv.org/abs/arXiv:1409.1837)).

In her blog post from January, she says:

 _" What Hawking is saying is essentially that he believes that a matter collapse only leads to a temporary apparent horizon but not to an eternal event horizon. That is an opinion which is shared by many of his colleagues (including me) and there is nothing new about this idea whatsoever."_

But in her more recent paper, she says:

 _" More specifically, we find that collapsing stars slow down their collapse right outside their horizon, while substantially reducing their mass through Hawking radiation. ... The star never crosses its horizon, so neither unitarity nor causality are violated, thereby solving the longstanding information loss paradox. This investigation shows that universally collapsing stars bounce into an expand- ing phase and probably blow up, instead of collapsing to a black hole."_

I am not a physicist, but when I read those two statements, they are in contradiction. The first statement says to me: it may not be an absolute horizon, but it is _a_ horizon. The second statement says to me: actually, we never reach any horizon. So I think that the more recent statement means that she has changed her conclusions based on her recent work.

<comment><USER31> I'm confused here. The mere existence of an event horizon - albeit a temporary one - should make a black hole! So "More specifically, we find that collapsing stars slow down their collapse right outside their horizon," by implying that a horizon DOES exist, simply doesn't cut it. Am I missing something?

<comment><USER4> I believe that's using the _concept_ of a horizon. For an object of a particular mass, we can use our theory to tell us where the event horizon would be, _if it collapses past that point_. My understanding of this recent paper is that they are saying: it won't collapse past that point.

</comment></comment></comment></comment><comment><USER32> > _a fundamental law of quantum theory states that no information from the > universe can ever disappear_

What is the name of this law?

<comment><USER33> [http://en.wikipedia.org/wiki/Unitarity_(physics)](http://en.wikipedia.org/wiki/Unitarity_\(physics\))

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

</comment></comment><comment><USER34> If I understand correctly, black holes do not play a large role in our model of the origins of the universe. So this doesn't (directly) lead to "rethinking the origins of the universe". Does this work call the big bang into question (or even our current models of the big bang)? Or is it just details like galaxy formation that it makes us rethink?

Another question: _Something_ very massive and very small is at the center of our galaxy. At least, we sure think so. Does this make us question that? Or does this just make us question whether that massive thing is in fact a black hole?

<comment><USER35> Your first point is correct: the relationship between black holes and the initial state of the universe is not clear. Whether or not there was a primordial singularity or something else is an open question.

With regard to the question "If not black holes, then what?", this is a problem. There is a strict upper limit on neutron stars of about 1.4 solar masses. Beyond this, gravity is stronger than the repulsive core of the strong nuclear force, and the star should collapse. If the process described in this paper is what actually occurs, the star will shed mass due to Hawking radiation while collapsing. The end-state of that process must be either a neutron star (which can't have more than 1.4 solar masses) or something else. There doesn't seem to be any "something else" in the offing, which makes that million-solar-mass thing in the centre of our galaxy deeply mysterious.

A new theory that makes an old "settled" phenomenon mysterious is not all that uncommon in the sciences, so it's reasonable to take a wait-and-see attitude toward this idea, but I'm not enormously hopeful that it'll pan out very well in the long run.

<comment><USER36> So it seems a cycle of collapse and Hawking radiation will occur until the star no longer has enough mass to collapse.

</comment></comment></comment><comment><USER37> My trust in metaphysical and other such sciences dropped significantly on the day I realized that most modern conclusions are just theories and half of them have already been proven wrong.

<comment><USER38> That is science at its best. What, indeed, is the alternative to admitting we were wrong when confronted with new and more accurate information? There is no "trust" in science, there is only truth, and you must always leave room for doubt.

Astrophysics appears volatile simply because there is so much we do not know, but that is also what makes it fascinating, and of critical importance.

</comment></comment><comment><USER39> Given how important this would be, it seems a bit odd that she just threw it on ArXiv rather than having it peer-reviewed. Also, the press release's explanation of what Hawking radiation is sounds strange to me, though I'm not an astrophysicist. It all makes me very hesitant to put any stock in this right now (well, at least it in meaning what's suggested here).

<comment><USER40> I understood that it was common to post the paper to arxiv when it was in the process of being peer reviewed by a journal. The problem is the extended lag time between submission and final publication with most journals which pre- print archives like arxiv try to solve. Do people really just "submit to arxiv" and then that it? I didn't know that, but its not common in my field to use arxiv so I have not kept up with all practices.

<comment><USER35> There have been cases where arxiv has been used as a venue of final publication, but the general intent is that stuff submitted there will eventually find a home in the peer-reviewed literature. There are sometimes exchanges of arguments there that never make it to prime-time, but that's not the dominant use-case.

The reality is, though, that people working in a given field are much more likely to use the arxiv version as the basis for further work, simply because it is available so much earlier. It is not uncommon to reach the point of publication and then run around to try and find out where all the arxiv submissions you used were published, which can sometimes be challenging.

</comment></comment></comment><comment><USER41> I'm not a physicist. I imagine that if I were, this would be exciting news (that is, an exciting possibility).

I _am_ a literary critic, though, and I have to say that it's bittersweet news at best. Black holes are so much a part of the space-age imagination. The article mentions Hollywood, but black holes are woven deeply into our everyday metaphors and have been for decades. They have stood among the most wondrous things in the universe -- an awe-inspiring thing.

It reminds me a bit of when the press reported that the Catholic Church had "gotten rid of Limbo" (the actual case was a bit more complex, and involved some fairly weighty theology).

Then again, we all still talk of things "being in Limbo." Perhaps that next project will still be a black hole, even if it turns out that there's no such thing.

<comment><USER42> I imagine that the metaphor "black hole" will be here for a while. After all, we still use the term "big bang" for the 'first moment' of the creation of the universe, even though the "Big Bang Theory" isn't generally believed any longer.

<comment><USER2> > even though the "Big Bang Theory" isn't generally believed any longer.

Really? Given that science doesn't turn on belief but evidence, still, the Big Bang remains the best explanation for existing evidence. It's the prevailing cosmological theory of the universe' beginnings. Like all scientific theories, it's subject to replacement as new evidence appears and as new theories are crafted, but it's a good match at the moment.

<comment><USER43> I think it's a bit naive to say that science doesn't turn on belief. Scientist aren't robots, mechanically and dispassionately ingesting evidence and spitting out theory. They're humans with imaginations, beliefs, agendas, and egos, guided (hopefully) by a methodology that leads to discovery. I think belief is what drives science, and it's not all that bad of a thing.

<comment><USER2> > I think it's a bit naive to say that science doesn't turn on belief.

That depends entirely on what we mean when we say "science". If by "science" we mean as defined and as practiced when it's done right, then no, belief plays no part -- it can't. If it did, it wouldn't be science.

> Scientist aren't robots, mechanically and dispassionately ingesting evidence > and spitting out theory.

Scientists aren't robots, but they are also not hothouse orchids.

> They're humans with imaginations, beliefs, agendas, and egos, guided > (hopefully) by a methodology that leads to discovery.

You have left the topic of science. The reason science exists is precisely because people are the way you describe them. Science is meant to be a counterpoint to natural human instincts, beliefs, passions, and other logical failings.

> I think belief is what drives science, and it's not all that bad of a thing.

You're now confusing science with religion. In religion, you let sincere feelings guide you to a conclusion. In science, you let _logic_ guide you to a conclusion.

In religion, something is true until evidence proves it false. In science, something is _false until evidence proves it true_ \-- exactly the opposite.

Much of scientific discipline is meant to guard against what we believe is true or want to be true. Experimental and control groups, the classic double- blinding precautions in human studies -- all are meant to minimize the corrosive, undermining influence of our beliefs.

The perfect religious follower is guided by belief, hoping only that his work reflects his passion. The perfect scientist doesn't care what conclusion his work comes to, hoping only that it reflects reality to the best of his ability.

Belief and science are in absolute opposition.

<comment><USER44> > [that it's naive to say that science doesn't turn on belief] depends > entirely on what we mean when we say "science".

Or it depends on what we mean when we say believe. The weight lying on "science" does form a conceptual framework that completely ignores the notion of something beyond our reach, although it inarguably is the driving force behind science.

> In religion, something is true until evidence proves it false. In science, > something is false until evidence proves it true -- exactly the opposite.

alright, but the word of god himself isn't evidence enough? j/k :)

> In religion, something is true until evidence proves it false. In science, > something is false until evidence proves it true -- exactly the opposite.

Why do those have to opposite, can't they be reconciled into one, using some form of ternary logic? Edit: I mean, some things in life are unknown until proven true or false and then theres all kinds of methods to counter the fact.

<comment><USER2> > The weight lying on "science" does form a conceptual framework that > completely ignores the notion of something beyond our reach, although it > inarguably is the driving force behind science.

Yes, but an idea doesn't become a matter of interest to science until it comes within our reach, in the sense of being observable in a way that forces different, similarly equipped observers to the same conclusion (the scientific meaning of "objective").

> Why do those have to opposite, can't they be reconciled into one, using some > form of ternary logic?

Yes, an interesting question, but not really about science. Science concerns itself only with things that can be reduced to empirical observation, not belief.

> I mean, some things in life are unknown until proven true or false ...

That's true, but the basic scientific precept is the null hypothesis, the idea that things without evidence are assumed to be false. This is a great time- saver compared to granting credence to ideas without evidence, or assuming that something might be true until proven false (the unscientific outlook).

<comment><USER44> I agree with your co-commentator, everything is subjective and we just take some things for granted so much that we take them as truth.

Seems i was wrong calling it inarguable, in fact i like to argue back and forth a lot.

> observable in a way that forces different, similarly equipped observers to > the same conclusion (the scientific meaning of "objective").

no, that's still subjectivity, you just shifted the goal post. That kind of subjectivity might be your threshold for accepting some cognition as close enough to your supposition of objectivity, but it still requires trust on an individual level.

> an interesting question, but not really about science. Science concerns > itself only with things that can be reduced to empirical observation, not > belief.

Specifically by including subjectivity through empiricism, you in fact beget belief. I.e. measurements have an inherit uncertainty and you do what you can to reduce it.

> but the basic scientific precept is the null hypothesis, the idea that > things without evidence are assumed to be false

You seem to fall for the fallacy of negated implication. My best guess is, the Null Hypothesis really states that evidence implies reality.

Or as my teacher put it, just because it didn't rain, the street doesn't have to be dry. It's hard to explain and I'm tired, sorry. I often fall for it, too.

<comment><USER2> > ... no, that's still subjectivity, you just shifted the goal post. That kind > of subjectivity might be your threshold for accepting some cognition as > close enough to your supposition of objectivity, but it still requires trust > on an individual level.

You're making the post-modern argument. Are you aware of this? Everything is subjective, there are no objective shared truths, it's all a matter of opinion. But you haven't thought this viewpoint through to its logical conclusion, which is that, if it's true, then it applies first to the argument itself, fatally undermining it.

<comment><USER44> I am aware of that, but I didn't think it through far enough to conclude that it's really undermined. I dunno, say, It only makes predictions about subjects, no the bigger picture, where a god-device would come in. It doesn't really explain away your stand point either. Good talk :)

</comment></comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER45> Another member of the peanut gallery here. I've not been bold enough to make any claim in writing (it would probably be full of misconceptions), but the black hole hypothesis always seemed a bit half-baked, and I've definitely said words to that effect in conversation.

In the hypothesis Einstein's field equations obviously break down, and instead of acknowledging that any explanation will be enormously difficult to test we seem to have bought into this completely untested idea that matter can continue bending space-time around into a singularity and all that. Can someone with a better understanding point out what logic is (probably) missing here?

The other thing that sets off my hand-wave-o-meter is the pretending that we are somehow already observing these things ("new telescope detects hints of black holes") or have concluded that they exist without any positive evidence. Instead of "the mass at the center of the galaxy which is so large that we currently have no good way of modeling it without a black hole" we hear "the supermassive black hole at the center of the galaxy" and so on.

<comment><USER4> My understanding of what Laura Mersini-Houghton's paper is claiming is that stars cannot collapse into black holes, but they can get damned close. So those things that we have observed are not "black holes", but things that are damned close. In the paper, she and her co-author write, "Both effects (slowdown and mass-loss) balance such that the evaporating star remains very slightly outside its event horizon."

Even if this paper is correct, I don't think it's warranted to be so smug about people thinking they found black holes. We had a theory, and we had positive evidence for that theory. That's reasonable. If this paper is correct, then it turns out those things are not actually "black holes", but objects "very slightly outside" of being black holes. That's not too bad.

Disclaimer: I am not a physicist.

<comment><USER45> What is an example of this positive evidence?

Also is it at all plausible that the center of the galaxy is evaporating slightly outside its event horizon in this way?

Anyway I'm not sure that the two of us are going to answer any of these questions without some help.

<comment><USER2> > What is an example of this positive evidence?

Are you asking what observational evidence exists for black holes? There are very massive, very dense objects at the center of most galaxies, objects that by their mass and density fall well inside the theoretical limits for black holes. At the center of our galaxy, there is a very massive, compact object, around which many stars are orbiting, in orbits that reveal the object's mass and approximate size:

[http://astro.uchicago.edu/cosmus/projects/UCLA_GCG/](http://astro.uchicago.edu/cosmus/projects/UCLA_GCG/)

This is pretty good evidence -- if the object weren't within the mass/density realm that allows for black holes, the orbiting stars couldn't approach it as closely as they do without colliding.

Again, this doesn't prove anything, it only supports the idea that black holes are possible, and that our observations agree with that idea.

<comment><USER45> I don't disagree with any of that, but the evidence in question still depends on several big assumptions.

<comment><USER2> It's the other way around. The evidence doesn't depend on the assumptions, the assumptions depend on the evidence.

The observations are very good and offer little latitude for interpretation -- there is a very massive, very dense object at the focus of multiple stellar orbits near the center of our galaxy, and both the mass and the density of the object are easily and unambiguously derived from the orbits.

It's the same with other galaxies -- a massive, dense central object dominates the orbital dynamics of the galaxy near its center. We're obviously not free to say that means black holes exist, it's just another piece of evidence. But it's a way to exclude certain alternatives.

<comment><USER45> Maybe it could be worded better. In order to say that gathering this evidence is the same as directly observing a black hole, we have to make several big assumptions.

</comment></comment></comment></comment></comment></comment></comment><comment><USER46> Now that all the physicists are reading, I have a question: Are the trajectories of light beams following the curvature of space-time reversible? In other words, if I reflect a light beam back on itself, does it return to its source?

Because if that's true (and my feeble understanding is that it is true), then light can't enter a black hole or the reverse path would allow light to escape. What am I missing here?

<comment><USER47> If the spacetime is static, then yes, the trajectory of a light beam (or anything else) is reversible. The question you pose is an excellent one and is one of the reasons that many physicists believed that black holes could not exist after Karl Schwarzschild discovered the Schwarzschild metric that describes spacetime around a spherically symmetric black hole.

So what happens if you direct a beam of light radially into a black hole? A distant observer will calculate that as the light beam descends into the black hole it will be (according to a distant observer) progressively blueshifted until it reaches the event horizon, at which point it will have blueshifted to infinite energy. In fact, according to the calculations of a distant observer, the light beam will never cross the event horizon, so the statement that the light beam is reversible remains true. The reason that the light beam (according to the distant observer) doesn't cross the horizon is that if you look at the metric, it states that ds^2 = (1 - R_Schw / r) c^2 dt^2 - 1 / (1 - R_Schw / r) dr^2, where R_Schw is the radius of the event horizon. Notice that at the event horizon r = R_Schw and the dr^2 term diverges. The distant observer therefore concludes that there is a singularity at the event horizon. This analysis lead physicists to initially conclude that black holes were unphysical.

A more careful analysis reveals that this isn't the case, however. We have been using this metric which describes the shape of spacetime according to a distant observer. But what we're really concerned with is not what a distant observer calculates, but how a _local_ observer perceives spacetime. If we now switch to a coordinate system in which we are free falling into the black hole along with the beam of light, we find that nothing remarkable happens when we cross the event horizon. The light is blueshifted relative to its initial energy, but it doesn't have an infinite amount of energy. Thus there is no true singularity at the event horizon. This singularity that the distant observer found must therefore have been an artifact of the particular coordinate system that the distant observer was using. The free falling observer can then hold up a mirror and send off a light beam and have it return back to him even after they have crossed the event horizon.

<comment><USER48> You have this backwards. To a distant observer, light going into a black hole is red-shifted, not blue-shifted. If this were not the case, sending even a single photon into a black hole would produce infinite energy.

<comment><USER47> No, any photons that are emitted from matter close to the event horizon and travel _toward_ the distant observer will be redshifted. Photons falling into the potential well of the black hole will be blueshifted. Of course, the distant observer is not able to directly detect photons falling into the black hole because he is far away from it. All he can do is calculate what he would expect the energy of the photons to be. This calculation gives an infinite energy as the photon approaches the event horizon, but it's not a "real" energy, so the black hole doesn't gain an infinite amount of energy.

An analogous effect occurs for an observer stationed at rest, hovering above the event horizon. Such an observer will observe the photons from afar to be blueshifed in agreement with the distant observer. Moreover, as this stationary observer gets closer and closer to the event horizon, the photons will be blueshifted to infinitely large energies.

<comment><USER48> Ah. OK, I misunderstood what you were saying. This is right.</comment></comment></comment></comment></comment>


FindTheBest - The comparison tool for everything  - <AUTHOR> http://www.findthebest.com/

<comment><AUTHOR> They recently redid their site, and it looks like they'll become pretty useful as they improve. While sites like PriceGrabber focus on regular purchases, they're trying to cover everything.</comment>


Free.cloudbrowser Not Working? - <AUTHOR> hey look i know little to nothing about internet or browser-esque things but i use this on my school chromebook because i am 16 without a phone, i opened a ssl server reader thingy and it said it is expired its pathetic but i need to use this, i cant really go into too much detail but it is the only way i can truly get ahold of my friends. why is it doing this? also something about security came up but this was the first time it ever ever did <comment><USER2> [https://www.isitdownrightnow.com](https://www.isitdownrightnow.com)

<comment><AUTHOR> it says it is down for them too...and i know the creator is on this website so im hoping he/she would stop in and say hi and tell me what is or isn't going on

</comment></comment><comment><AUTHOR> so every free proxy web browser website ever is blocked or expensive and this chromebook cannot download anything. so im really at a lost. i need to know if there is absolutely anyway i can be able to use free.cloudbrowser (assuming it is not blocked) or something like it. or should i email cris??

</comment><comment><AUTHOR> the reason i am 16 without a cell phone is because i had to move into my grandparents home in september due to my only guardian dying in our home in july. they are not super old but im a 16 y/o girl and they dont trust me on the internet. thanks and im sorry to intrude.

</comment><comment><AUTHOR> my friend explained to me that it has something to do with the certificate expiring and that i just have to wait until it comes back online. but im scared my school will still block it

</comment><comment><AUTHOR> i would email him but i am afraid of my full first and last name being known...</comment>


What the boss makes: executive pay in Silicon Valley - <AUTHOR> http://www.mercurynews.com/top-stories/ci_15270090

<comment><USER2> On a related note, is there any way to get executive/managerial pay info for Silicon Valley startups?</comment>


Climb In, Tune In: A Renaissance for Sensory Deprivation Tanks - <AUTHOR> http://www.nytimes.com/2015/10/18/us/climb-in-tune-in-a-renaissance-for-sensory-deprivation-tanks.html <comment><USER2> I tried that very location in Colorado. My experience was good though not earth shattering like Joe Rogan makes it out to be. Then again, I didn't ingest any edible cannabis prior to jumping in like he does.

I would like to try again though. That location is clean albeit not very spa like. I can see where the Wild West aspect of it might be a problem for some places though. It's probably best to research places first. Even stop by for a visit prior to floating.</comment>


Man finds his way home using Google Earth - after 25 years - <AUTHOR> http://www.themercury.com.au/article/2012/03/10/308081_tasmania-news.html

<comment><USER2> While I love the story, I think the headline gives too much credit to Google Earth. He was able to find his home by joining a Facebook group and asking people. Yes, he used Google Earth to find the town; but he was able to find his way home only by emailing people.

Regardless, it's a great story. Whenever technology (be it Google Earth, or Facebook) makes such a positive impact on someone's life, I find it uplifting.

<comment><USER3> And specifically an application used to view satellite imagery, rather than the company that produced the imagery. They might as well credit Internet Explorer instead of Facebook. Taken to an extreme, they could have credited Windows XP for the reunion.

Somehow Google Earth is often credited for anything involving satellite imagery. He probably actually used Google Maps.

<comment><USER4> It sounds like he used a combination of Arial footage and street views to locate the town. Having located it he could have traveled there or even called, but instead use other services to talk to people in the area. So, IMO it really was Google street views coupled with maps that let him find the place.

PS: _He remembered the Khandwa train station and surrounding area_ not a street name and not what the area looked like from space.

<comment><USER5> @sausax, no need to think whether Google have street views (note not Streetview) in India - [http://maps.google.com/maps?client=ubuntu&channel=fs&...](http://maps.google.com/maps?client=ubuntu&channel=fs&q=Khandwa%20train%20station&oe=utf-8&gl=uk&um=1&ie=UTF-8&hl=en&sa=N&tab=wl) is an image of Khandwa station on Google. IIRC Google Earth have used Panoramio (sp?) for location images for some time, longer than they've offered Streetview or indeed location views on Google Maps.

<comment><USER6> Any particular reason to chose Khandwa? (I am curious as I am from that town and it is not particularly well known)

<comment><USER5> Unless I made a mistake Khandwa is where the man was from and he tracked his family from a memory of the station there.

</comment></comment></comment></comment></comment></comment><comment><USER7> My OCD kicks in.

Where does this odd thing come at the end of the article? "The older brother who accompanied Mr Brierley on the train ride was found dead on railway tracks."

Earlier in the article, it was written that Saroo boarded the train after he got lost. No mention of older brother, which made me think he was alone.

<comment><USER7> Also fuck poverty. I hope we can wipe poverty off the earth soon.

<comment><USER8> _I hope we can wipe poverty off the earth soon._

Most of the industrialized world can be said to have done that.

Western Europe, Japan, probably Canada too. It is easy* and requires only low levels of corruption, good law and order, combined with mostly free markets. Wealth in terms of natural resources is NOT a requirement, Switzerland is resource wise very poor. (Unless you count scenic views of the Alps as a resource.)

*When I say easy, I mean possible and requires only changes in human behavior - so super hard in fact.

<comment> DanI-S I suspect it may also require the systematic exploitation of the remainder of the world through aggressive pursuit of unfair trade agreements and projection of military force abroad, but I may be wrong.

Also: the help of a larger, richer friend overseas who is much less concerned with equality.

<comment><USER8> It is true the OECD countries are currently bending the developing world over backwards. But this does not mean that the OECD _needs_ that kind of advantage. We might not be as rich without it, but we would still be quite rich.

Also there's very little military projection from the Scandinavian countries for example.

And I am not sure how the overseas friend helps? If you look at median (not average) GDP per capita, the US is actually _less_ wealthy than many European countries. Plus, in terms of trade with Europe, the US is as much a competitor and exporter as it is an importer.

So I'd say Western European or Scandinavian style prosperity is definitely possible without UK style ex-colonialism, or US style inequality and military projectionism.

<comment> DanI-S You make some good points. I figured that US involvement probably has a hand in ensuring us a steady supply of fairly low priced oil, but you're right that other factors may counteract this.

Honestly, it seems so hard to imagine a 20th Century without US influence that it may not even be worth the effort.

<comment><USER8> Well the US military involvement does mean it gets some of the lowest priced oil. What's the price of a gallon of gasoline up to in Europe now, $9 or something? I think most of the time it is something like triple what the US pays.

And yet that has not crippled the European economies when it comes to trade with the US. European cars are more gasoline efficient, and Europeans live closer together (although this may largely also be due to historic reason long predating the automobile).

And I think the fear that oil might be radically more expensive for everyone, unless someone ensures it keeps flowing, is unfounded. If oil is valuable - people will look to sell it.

Didn't certain groups in Iraq partly fund themselves by exporting oil in pickup trucks? That's what I mean. Even if an oil exporting area turns to complete and utter chaos, strong men will arise and they will look to get rich by selling oil. And how long could the oil exporting states maintain their quality of life without massive oil exports?

I think you'd have to actively fight to prevent oil from trading rather than the other way around.

But it is also true that Europe might look radically different if the US had not pushed for democracy in the west.

That's what's really so depressing about the US and the rest of the world slowly sliding towards more and more authoritarianism. Who will be guiding beacon of freedom in the coming centuries? Switzerland is not big enough to strong arm anyone into being more democratic.

<comment> DanI-S I'd argue that European gasoline is more expensive purely because European gasoline taxes are higher - the underlying commodity has a similar cost. European governments benefit from being able to charge higher taxes on fuel because US foreign policy helps keeps the oil price down. Thus, they're indebted to the US, which the US knows.

But yeah - I agree. Authoritarianism is definitely not the way to a prosperous world.

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER9> Impressive - how many people have concrete enough memories from that age? I have maybe one I could use to locate somewhere, but otherwise that age is lost to me.

<comment><USER10> I can't help but think that at five years old I could have told anyone that I lived in Oxford, and therefore wouldn't need to remember what it looked like to find my way back there 25 years later.

Am I wrong about the ability of five year olds?

<comment><USER11> Many places in India don't have definitive addresses. They tend to be relative, such as "across from the train station." And I suspect that when you live in the slums and are begging at the age of five, your world is quite small -- the chances that you might leave town on a trip or know someone who's not from the same area are slim. So you likely don't need to know, much less practice, the name of your town.

</comment></comment></comment><comment><USER12> Yet another example of how hard it is to predict how a product/technology will be used or what societal benefits/detriments it might provide.

</comment><comment><USER13> Vow, first i thought this is the plot from a bollywood movie.

<comment><USER14> There has been too many. But Bollywood doesn't need billions of dollars worth technology to reunite families! We have (a)fate and (b)a song that the families sing and dance to in happy days(kids are young, they learn fast). Decades later, due to fate family gets placed into a 1 mile radius, and the kinship-proximity sensor gene trigger the release happiness hormones which in turn makes the family members break into song and dance. Technology is catching up it seems ...

</comment></comment><comment><USER15> > Mr Brierley said his mother told him of how they had searched endlessly for > him after he went missing and saw fortune-tellers who told them they would > one day be reunited.

Hah. I bet they did.

</comment><comment><USER16> Good to see that google is finally running an efficient PR department :-)</comment>


A radical new way to monetize mobile applications - <AUTHOR> http://contrib.io

<comment><USER2> "The deveoper portal" -> "The developer portal"

Also I would recommend including details on how the payment part of this actually works.</comment>


Ask HN: fast and easy way to set up a personal website with blog - <AUTHOR>

I am planning to set up a personal or family website, with domain name, virtual host, blogs and just very simple webpages.
I don't want to spend much time on the setup and maintenance, no fancy or latest techs needed. What's the fast and easy way? It is better a whole package with all things needed. But it must be a host I can manage, not a third-party one like Blogspot.
My current plan is Linode+GoDaddy+Wordpress. Any ideas and suggestions? <comment><USER2> I wouldn't use Linode. Not that I don't love Linode but for a simply family blog it's total overkill. I use DigitalOcean for a couple of smaller sites and have no problem with them (and costs $6/month as opposed to $20/month with Linode).

I also use Jekyll which is a static blog generator. I use Bitbucket to directly edit the pages and posts on my blog and when I commit a change my blog is automatically regenerated via service hooks. That might be a bit more setup than you want but it works nicely and is easy to maintain.

</comment><comment><USER3> [https://posthaven.com/](https://posthaven.com/)

</comment><comment><USER4> Switch Godaddy out for another registrar and it sounds like a plan (personal opinion). Linode is good, I use them too, but might be overkill for what you need unless you already have active hosting with them.

</comment><comment><USER5> I'm using [https://ghost.org/](https://ghost.org/) and its been great so far.

</comment><comment><USER6> Dunno Linode, but Digital Ocean makes sense for these requirements.

</comment><comment><USER7> Linode+GoDaddy+Wordpress is a Good Choice.</comment>


Official Sweden Covid case and mortality stats - <AUTHOR> https://experience.arcgis.com/experience/09f821667ce64bf7be6f9f87457ed9aa <comment><USER2> So, why are the deaths and intensive care cases dropping continuously?

<comment><AUTHOR> 1) better protection of nursing homes 2) better treatments 3) herd immunity

</comment></comment><comment><AUTHOR> Google no longer allows users to see deaths in Sweden in their search result UI (it's greyed out as of last week), so now one has to go to government website directly.</comment>


Management guru C K Prahalad passes away - <AUTHOR> http://economictimes.indiatimes.com/news/news-by-industry/et-cetera/Management-guru-C-K-Prahalad-passes-away/articleshow/5825234.cms

<comment><USER2> He was such a nice, approachable guy. Was fortunate enough to meet him at a TiE presentation once - he championed so many ingenious yet simple ideas in the developing world.</comment>


The End of the Past - <AUTHOR> https://medium.com/@MarkKoyama/the-end-of-the-past-2f028cb970ed <comment><USER2> A good article with an opaque headline that gives no clue that it compares the ancient Roman economy to the early modern one.

I agree slavery was very important but, early modern Europe had slavery too. It begs the question to just say slavery was less important to the modern economy: why was that? One difference is that early modern Europe, for all its wars, had no dominant apex predator like the Roman Republic.

True, the Republic fostered advanced trade -- it was wise enough not to destroy provincial economies. But aristocrats still lived off the taxes and bribes payed in conquered lands.

This meant that if you had some wealth, the best investment for it was to bribe your way to a government post. This general pattern lead to the empire, and to its corruption.

It also explains the rentier culture that the article describes.

<comment><USER3> Yes, it's important to read such claims exactly and literally - as the OP states, " __ _Roman Italy_ __had comparable per capita income to the Dutch Republic in 1600 ". Assuming that this is true, it is still clear that Roman _Empire_ and even more so Roman _Egypt_ did not have a comparable income.

Roman Italy was fed and clothed by products of non-Italian economies; It's easy to get a multiplier of your GDP if you have landowners that "farm" overseas land with overseas slave labor that isn't part of your economy consumption.

<comment><USER4> There's a recent book by Ober, _The Rise and Fall of Classical Greece_, pointing out that the pre-Roman Greek world had per-capita income that high. I think a better question is why did _that_ culture not keep advancing, and maybe the biggest part of the answer is that they got conquered by Rome.

<comment><USER2> But first they were conquered by Macedonia -- was Greek in many ways, but it did not have the political culture that Ober says distinguished the Poleis.

<comment><USER4> I'm including the Hellenistic era. It continued to grow economically at well above normal preindustrial rates (according to Ober), if not quite as high as in the classical period. Technological progress might've been even faster then -- it was the time of Archimedes and the Antikythera device, and much else. (Russo, _The Forgotten Revolution_.) Ober concluded with a post-Alexander chapter: the Hellenistic cities were not completely at the mercy of empire- building despots because a walled city at the time was very hard to conquer (instead of starving out) leaving a Nash equilibrium where cities paid substantial taxes but weren't messed with too much in their internal politics, so that much of that culture survived for quite some time.

(From my memory of a book I read a year ago.)

I'd guess that even without Rome, military technology & organization would've made cities increasingly vulnerable, and it'd have been a race between increasing despotism from such developments and the fact that freer more dynamic societies also have a kind of military advantage (see Archimedes again at Syracuse). But of course I'm indulging in total speculation.

</comment></comment></comment></comment></comment><comment><USER5> (Title is poorly chosen.)

I've asked this question before - why didn't the Roman Empire progress to an industrial revolution?

The Roman Empire never developed the concept of the corporation. They never got beyond the "one rich guy" or "rich family" stage of business organization. They never had much in the way of inter-city businesses. They didn't have common carriers for shipments. They had the roads and the legal system to make that work, but somehow never developed something like Wells Fargo, the stagecoach line. They lacked the organizational tools to scale a business.

The Roman Empire had figured out how to scale government, training provincial executives in Rome and sending them out to govern. The Empire had a sizable grain and oil shipping operation, but this seems to have been done as a Government contracting operation, not as a private business.

Another argument is that the industrial revolution needed coal, iron, and water power in reasonably close proximity. Italy doesn't have much of that that. England and France do. So do parts of the US. Once you've got railroads, the proximity doesn't matter as much, but until then, it's hard to get started.

The political importance of land ownership may have been an obstacle, but England had a landed gentry all through the Industrial Revolution. The landowners couldn't stop progress, although some of them opposed it. They couldn't even stop railroads; Parliament could and did approve "compulsory purchase" of the right of way.

It's a good question. For a thousand years, the Roman Empire couldn't solve this basic economic problem. What are we missing about our own society?

<comment><USER6> The concept of a company is not important to economic and technological progress. In fact, it's actively detrimental to it.

<comment><USER7> I'm not sure how you come to that conclusion, let alone your confidence in it.

A corporation allows for both pooled and limited risk.

This permits a civilization to take on large projects such as building a railroad or a refinery - activities that were both expensive and financially risky.

The only other alternative is the State, but then that involves taxes and keeping the populace happy, which tends to impede progress. Things like the Coliseum get built instead of railroads.

Individuals have high tendency not to do it because once people have attained a certain amount of wealth, they are more interested in protecting against losses than taking on expensive risky projects. Daniel Kahneman wan a Nobel prize for work related to this kind of decision making ([http://www.apa.org/monitor/dec02/nobel.aspx](http://www.apa.org/monitor/dec02/nobel.aspx)).

</comment></comment></comment><comment><USER8> The author links to pseudoerasmus's blog post about Empire of Cotton as if it were a refutation of Empire of Cotton's thesis. But that blog post is a summary, not a critique--the author says this explicitly in its comments. The closest the author comes to a critique is an aside in this post: [https://pseudoerasmus.com/2015/04/26/mccloskey-cotton- ir/](https://pseudoerasmus.com/2015/04/26/mccloskey-cotton-ir/) with similar points made earlier in: [https://pseudoerasmus.com/2014/11/10/slavery_and_industriali...](https://pseudoerasmus.com/2014/11/10/slavery_and_industrialism/)

...which is far from open-shut, in my reading of it. It's a tangential point, I guess, but worth considering in evaluating the plausibility of the whole argument.

<comment><USER2> Just in case anyone is wondering, the linked pseudoerasmus post is: [https://pseudoerasmus.com/2016/06/16/eoc/](https://pseudoerasmus.com/2016/06/16/eoc/)

</comment></comment><comment><USER9> > Was the Roman economy only as developed as that of Europe circa 1300 or was > it as advanced as that of western Europe on the eve of the Industrial > Revolution in say 1700.

The question is ill posed. It assumes that economies move on a linear scale - with definite positive and negative directions. Was the economy of the Soviet Union in the 1930s more advanced than that of the Dutch Republic in the 1600s? Well, the USSR could produce tractors and icebreakers. But the Dutch had a stock market and a really good internal transportation network.

</comment><comment><USER10> Makes me wonder: Would the slavery-based economy of Roman times represent a model for what will be the robot-based economy of the future?

<comment><USER11> That was my first thought as well. Another thing that came to mind is that way manual work / craftsmanship was looked down upon has its parallels in the present day, particularly in the US. It's often said that other parts of the world see engineering in particular as a prestigious line of work, but the same cannot be said for the US. It's strange how the US lauds only the extremes: either very blue-collar manual laborers, or very white-collar 0.001%-ers (very often rent-seekers who don't actually add much value to society). People who actually engineer things and drive innovation are not looked up to.

<comment><USER12> > People who actually engineer things and drive innovation are not looked up > to.

In the US? Compared to whom? Doctors? Bankers? Lawyers? Politicians?

Who do you think that you are better than?

<comment><USER13> I don't know about the US but here is Australia Engineers are consistently rated as one of the most ethical and trusted professions eg. [http://thenewdaily.com.au/money/work/2016/05/14/most- trusted...](http://thenewdaily.com.au/money/work/2016/05/14/most-trusted- professions/)

Most of my ethics course from university focused on US based case studies (Tacoma Bridge, Kansas City walkway collapse, Space Shuttle etc.) So it could be possible Engineers in US have a worse reputation.

</comment></comment></comment></comment><comment><USER14> There is potentially a really simple answer to the question, "What happened in England in the 17th Century and changed everything?"

Isaac Newton.

I'm surprised that historians don't consider that possibility, at least to the extent required to exclude it.

<comment><USER15> It's an interesting proposition. There is certainly a history of scientific paradigm shifts, although I don't think it's very popular among historians.

Consider also the printing press. Invented much earlier, but something which built up momentum as it was improved and paper was made cheaper.

Perhaps the improved ability to disseminate information made the industrial revolution inevitable?

</comment></comment><comment><USER16> Holy cow, dudes!!! There is a massive cultural overload in all these comments! Are you really the same guys who code websites all day/night long?</comment>


Prosper is Back - <AUTHOR> http://blog.prosper.com/2009/07/13/welcome-back-lenders/

<comment><USER2> Prosper indeed is technically neat in some aspects. However, default rates for most lenders are sky high: According to outside estimates, 9 of the top 10 investors on Prosper will end up with a negative ROI, despite lending at double digit interest rates: <http://www.ericscc.com/tools/prosper-lender- list>

Before investing a sizeable amount, consult external sites and/or observe a smallish portfolio for 6 months or so.

<comment><USER3> the issue there is that you're looking at people with huge lump sums who spread their money around as much as possible. if you just throw your money around equally at everyone, you'll probably not come out in the black.

if you invest in a more targetted, calculated way, you'll be _more likely_ to come out with a good return. there are plenty of accounts with 10%+ estimated ROI on that list. take a look at how they invest, there are some trends.

disclaimer: i've not invested any money in prosper, but i was considering trying it out right before they shut their doors. i've done some homework on it.

<comment><USER2> The top 10 I mentioned had a wide variability of strategies, and I can assure you that they all thought they had a plan.

If you only look at lenders with a sufficiently large (20 loans) and aged (365 days) portfolio to make an evaluation plausible, only 167 lenders of more than 19000 lenders in that category had an estimated ROI of >10%.

Of the 1161 lenders with more than $10K invested and a portfolio older than 365 days, exactly _3_ had an estimated ROI of >10%.

The <http://prospers.org> discussion boards are full of guys who've done their homework. The test is how their loans fared, and generally they haven't fared well.

disclaimer, which I should have stated above: I've invested $1K a few years ago, and am more or less breaking even at the moment.

<comment><USER4> Since you are someone investing there, and investing normally being something that you do carefully, how come everybody is falling over each other to park their money there ?

You'd think they had a very positive track record wrt to ROI, but I only find evidence to the contrary.

It's almost as if lenders are lining up and they have a hard time finding people to borrow to, in 'the real world' you'd expect it the other way around.

<comment><USER2> The stats I have seen would indicate that lender interest peaked around May 2008, and e.g. %age of listings funded decreased May-Sep: <http://www.ericscc.com/stats/prosper-listing-volume>

Unfortunately, I have no good historical stats on interest rate paid by borrowers, which would probably be the best metric for lender/borrower interest.

</comment></comment></comment></comment></comment><comment><USER5> That is a formidable barrier to entry.

<comment><USER6> but lending club beat them to it... or am i misunderstanding?

<comment><USER5> I was referring to SEC approval to do something unorthodox with securities online. I'm ignorant of the space, so it's quite possible someone beat them to it.

</comment></comment></comment><comment><USER7> Also in this space are LendingClub, who don't do auctions but have a similar model of letting people buy portions of other people's loans. They claim an effective APY of just under 10%; I've invested a (very small) sum with them as an experiment and so far am on track to hit that APY (after 2 months).

</comment><comment><USER8> I took out a small loan with prosper 3 years ago and it's definitely a quick and easy way to get cash if you have good credit.

</comment><comment><USER9> fantastic! Just signed up.</comment>


Twitter Engineering Blog: Faster Ruby (Kiji Update) - <AUTHOR> http://engineering.twitter.com/2011/05/faster-ruby-kiji-update.html

<comment><USER2> This doesn't add up for me. Unless they've been working on this for a long time - at least a year, why did they pick the very slowest current version of Ruby to start this process with?

Ruby 1.9 gives you an easy doubling of performance from base Ruby 1.8. Ruby Enterprise Edition is a worthy upgrade to the 1.8 codebase, but 1.9 is where the action should be. I haven't used 1.8 for over year, 1.9 is that good.

For some reason they mention maybe trying Ruby 1.9 and JRuby at some future time.

If you care about performance, and you want to play with heap implementations, then the JVM has you covered. JRuby is the version I would have _started_ with just to play with GC settings.

I'm all for playing with stuff to find things out, but this feels like they aren't spending their time wisely to get the result that they need.

<comment><USER3> 1.9 doesn't always result in speed improvements. We benchmarked some of our code against REE and 1.9.2 and the difference was negligible, if at all.

I agree with you however. 1.9 is the future and that's where they should be spending their time. Let 1.8 die already...

</comment></comment><comment><USER4> Ruby needs a modern garbage collector, so I guess this is a step in the right direction.</comment>


Matasano brand officially retired by NCC Group - <AUTHOR> https://twitter.com/tqbf/status/605498999752163329

<comment><AUTHOR> The games - Microcorruption and the Crypto Challenges - aren't going anywhere.</comment>


Who is hiring product managers? (April 2017) - jamey-aha https://www.roadmap.com/hiring-product-managers-april-2017 <comment> purple-cow Thanks for posting! If anyone is looking to hire product managers, the April thread is the place to post. If you're looking for jobs, make sure to check out the March thread too [https://www.roadmap.com/hiring-product-managers- march-2017](https://www.roadmap.com/hiring-product-managers-march-2017)</comment>