Alone in a Crowded Milky Way - <AUTHOR> https://www.scientificamerican.com/article/alone-in-a-crowded-milky-way/ <comment><USER4> I don't buy this argument. Let's pretend for a moment that there are currently 5-20 intelligent species in our galaxy, and everyone except us developed deep space ships and successfully colonized thousands of other planets (make up almost any numbers you want here; the results still hold).

What would our telescopes see? It seems like we would most likely see exactly what we see today.

The probability that one of those ships happened to fly anywhere close to our solar system, while we were looking, is still vanishingly small. Omnidirectional radio transmissions spread so quickly that they fall below the noise floor almost instantly over interstellar distances.

Space is really really really _really_ big. We can see stars. We can just _barely_ see some planets in a few _very_ specific configurations. We can sometimes make coarse estimates of the chemical composition of those planets. And that's about it. We don't really know how to detect life on extrasolar planets. The ones we've already found could be teeming with life and we wouldn't know it.

<comment><USER5> Why would they stop at thousands of colonies? What is it preventing the colonies from themselves creating colonies? Also, realize that a colony in the system of another star will move away from the originating system. In our neck of the galactic woods the rate of separation is typically about 10^-4 c, so in a million years they'd separate by 100 light years.

<comment><USER6> The problem with endless expansion is it requires stability over very long time scales. Sending a probe to another solar system is hardly enough. If you can send a ship say 100 light years from your home planet that's 2,000+ repetitions of terraforming and colonizing a planet, building up an industrial base, then sending ships to every planet in reach. Under ideal conditions that might take 10,000 years assuming everything went well so you need 20 million years to colonize our galaxy. But, assuming everything goes well for 20 million years and colonization continues to be a priority seems unlikely.

It's very possible to reach a wall where zero teraformable planets are within reach of your ships. For large civilizations that's unlikely to totally block expansion, but it might make the path very convoluted thus increasing total time by a rather extreme factor.

<comment><USER7> Culture rot will kill you quicker than density of colonisable planets.

The transport layer is the easy part. Content integrity is a much harder problem.

All of your probes and colony ships have to reproduce the source culture - <USER2> some viable subservient spin-off - with 100% accuracy.

This explicitly means 100% reproductive success of all features, especially the politics and economics, with no errors.

For a successful colony, stability and conformity have to be maintained for long periods - centuries at a minimum, perhaps even millions of years.

And of course this assumes the source culture is stable in the first place.

Otherwise you're just seeding the galaxy with potential competitors, and/or setting up some kind of galactic Battle Royale.

I'm bemused by the suggestion the first option is actually possible. The second seems more likely, but might not be considered a success in the sense of creating a stable galaxy-spanning civ capable of common strategic goals.

<comment><USER8> > All of your probes and colony ships have to reproduce the source culture - > or some viable subservient spin-off - with 100% accuracy.

The only thing that needs to be preserved is the desire to build more colonies. I'll grant even that's a stretch, but demanding 100% cultural fidelity is silly for discussing the Fermi paradox.

<comment><USER9> > The only thing that needs to be preserved is the desire to build more > colonies

That's hard. I'd say harder than solving the physical problems of interstellar travel. Once a generation has learned to live with the limited resources of a starship, living with the limited resources of a planet is going to be a very attractive option. What's their incentive to colonize more from there?

<comment><USER10> It's always going to be a small percentage that desires to venture further out to new areas. On a newly settled planet, most will not want to leave. But some will.

<comment><USER9> But you have to wait for that society to forget that living on a starship means spending your whole life never venturing out, while a planet lets you spend your life exploring.

<comment><USER11> Or, you know, some just want to get away from the other individuals.

That is, if we are talking about something comparable to current humans. Immortal super AIs might don't care about idling in the void for a few million years, just for the opportunity to re-sync those gained experiences to their decentralized knowledge a few million years down the line. I really like the single omnipotent AI scenario, since being immortal and not depending on others changes quite drastically what strategies can be successful - it won't be anything like human kings who need to keep their subjects at bay and working for them to support their power and limited life. But we shouldn't restrict our imagination, if we are talking about possibilities and galactic time-spans.

The important part is, as mentioned by GP, the desire to expand, since this is a dominant strategy. In comparison, not every living being on earth has the drive to participate in evolution by e.g. creating offspring. Those usually just drop out of the "game" and likely won't matter in the long term, at worst making it a bit harder for the others initially till their disappearance. What matters are those who have persistent impact... e.g. by colonizing/making offspring.

</comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER12> Discussions of the Fermi paradox get swamped with people's individual hypotheses. It's nice to see an article that tries to develop a whole different _kind_ of answer. The known possibilities seem to be:

1\. We're alone (or very nearly so) due to an early filter. i.e. it was vanishingly unlikely for life to develop as far as it has here.

2\. We're alone (or very nearly so) due to a late filter. i.e. life develops in lots of places but, terrifyingly, it becomes overwhelmingly likely to wipe itself out rather than spread.

3\. Life develops frequently but there's some sort of interstellar ecology that makes species stay hidden or be wiped out.

4\. Life develops frequently but is overwhelmingly likely to develop some other interest (becoming inward-looking, or exploring other dimensions) rather than colonising all of space.

This article's suggestion that Earth may be in a backwater wouldn't be sufficient by itself, so it is coupled with the idea, derived from observations on human colonisation of Micronesia, that expansion happens in waves and life on Earth happens to be in between waves. The problem is, advanced technological civilisations expanding across the galaxy isn't the same thing as Polynesian explorers eventually being followed by Europeans. Why would the waves die away? This is a late filter with extra steps.

<comment><USER13> 5\. No Aladdin's lamp. There's no FLT, no wormholes, no solution to the huge distances. And/or interstellar space is so full of toxins or plasmas no lifeform can survive it. And/or all EM data transmissions are reduced/scrambled/swallowed/encrypted by the void. All the experiments are naturally locked in separate containers.

6\. _Klaatu barada nichto._ We are indefinitely locked in solitary, incommunicado, for creating and using nuclear weapons. On ourselves. Immediately.

<comment><USER14> I find (6.) somewhat anthropocentric in that it assumes nuclear weapons are the _nec plus ultra_ of destructive power. You might as well have said in 1917 that we were incommunicado for inventing chlorine gas, or shotguns (whose use the Germans did object to as a war crime!)

<comment><USER15> They aren't. We almost have the capability to do much worse ourselves already. If you want big-bang type weapons, you can modify an asteroid orbit to drop a K-T event on the planet. It's not very target-able, but if you want to try and wipe out civilization, it would be pretty effective.

</comment></comment></comment></comment><comment><USER16> I find most Fermi-paradox arguments drift towards being too biology-centric even if they acknowledge the possibility or probability of a transition to machine-based life.

For example this paper assumes that you need classic "habitable worlds" to colonize a solar system, but it's unclear why machines would need more than relatively small rocks or comets.

The paper also assumes that each colony needs to operate as a continuous entity and can therefore collapse or experience massive cultural shift. But if it's all machines, then you can put some powered-off seed ships in long orbits for cheap self-recolonization (seems strictly easier than crossing interstellar space in the first place).

I'd like to see more studies on the feasibility of those ultra-long-lifetime interstellar ships (assuming plausible tech like general AI). Maybe there are thermodynamic or other reasons why that can't be done.

(Personally I'm in the camp of "abiogenesis is actually really hard so we're the first civilization in our light-cone; the doomsday argument holds, and will be a theistic eschaton".)

<comment><USER17> Machines need to be maintained. Machines of useful complexity include such parts as microprocessors. To create new or replacement parts, nothing less than the full Earth industrial complex is required. It's not clear how to package all that in a ship, including enough reserves to bootstrap an industry up to the point it is possible to build microprocessors. I doubt that "machine life" could subsist on a small barren rock with more success than biological life.

<comment><USER16> It's very interesting to consider what would be required for a minimal industrial complex that supports microprocessors. My intuition is that it would be much smaller than "the full Earth industrial complex". Seems like a question that is actually answerable with research, and potentially important too as a hedge against our current industrial complex collapsing.

<comment><USER18> Here's an article on that: [http://caseyexaustralia.blogspot.com/2018/09/how- to-industri...](http://caseyexaustralia.blogspot.com/2018/09/how-to- industrialize-mars.html?m=1)

<comment><USER16> Excellent link, thanks! That's exactly the sort of analysis required, though a lot more is needed.

I didn't follow why mining has to be (or should be) so human-labor-intensive.

</comment></comment></comment></comment></comment><comment><USER19> The problem with these types of arguments is they are assumptions built on top of other assumptions.

We don't know how to colonize other star systems, so we don't really know the factors at play. How easy is it to travel to another planet and start a colony? We don't know. How likely is it that that colony will colonize other planets? We don't know. We are taking numbers we guessed and multiplying with other numbers we guessed to get to an answer. If any of them are much off the answer doesn't make sense?

What if the amount of resources to successfully travel to and colonize a planet in another solar system is so high that the vast majority of attempts fail and only a few attempts can be made? We can have n (pick some random large number) intelligent civilizations in our galaxy and not know a thing about them.

<comment><USER20> My thoughts exactly. I've always found it funny how people imply there's some major issue with cosmology because the Drake equation shows there should be intelligent life all over. Even though some of the terms in that equation are very not known and it would only take a few being an order of magnitude or two smaller than expected to result in a paucity of intelligent life rather than an abundance.

<comment><USER19> Right. The Drake equation was never supposed to "show" anything. I think the original intent was to lay out the factors at play and stimulate conversation, not to provide a probability. I think over time, the imagination of the public have taken over though and put more confidence behind things than we should.

</comment></comment></comment><comment><USER21> So this article started as a good intro and overview of the Fermi Paradox (which is somewhat of a misnomer because as far as Fermi was concerned it wasn't a paradox at all) but it faltered at the end when it talked about habitable worlds.

This is a topic Isaac Arthur [1] has gone into great depth about. If you haven't found his YouTube channel yet prepare to lose several days of your life. I find his arguments here compelling.

Basically planets only matter as a source of raw materials. Planets are highly inefficient ways of creating living area. The most likely outcome for a spacefaring civilization is actually a Dyson Swsrm. 1% of Mercury's mass used this way could create orbiting habitats that support a quadrillion people and fully utilize the sun's power output (a so called Kardashev-2 or K2 [2] civilization).

And these are simply O'Neil Cylinders [3], which don't require any materials that don't already exist.

The beauty of this is it doesn't require much more technology than we already have. Better yet, it doesn't even require commercial nuclear fusion (personally I'm not yet convinced this is even viable).

Take this further and a K2 civilization is not subtle and is highly detectable. For it not to be violates thermodynamics. We've seen no evidence of any K2 civilizations within millions of light years, which suggests their existence is highly unlikely (within the cone of spacetime we can observe).

Given this seems to be such a natural evolution you can extrapolate and say that we are pretty much alone.

Remember it's not about what most civilizations do because it only takes one to go this road. The argument that no civilizations become K2 civilizations use much harder to swallow than a few do. This notion gets more absurd the more civilizations there are.

[1]: [https://www.youtube.com/channel/UCZFipeZtQM5CKUjx6grh54g](https://www.youtube.com/channel/UCZFipeZtQM5CKUjx6grh54g)

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

[3]: [https://en.wikipedia.org/wiki/O%27Neill_cylinder](https://en.wikipedia.org/wiki/O%27Neill_cylinder)

<comment><USER22> These are all under our current understanding of physics, which does a good job, but we know it's not the full picture. Matter, the stuff you and I are made of, is ~5% of the universe's mass-energy. We understand the physics of this stuff fairly well.

Dark Matter is, as far as we can tell, is entirely made of stuff that falls down and does nothing else. Dark Matter is ~25% of the universe. We have a fair few theories of what Dark Matter is, if/how we can use it, how to make it, move it, etc, but it's still very active research. We have a toehold on Dark Matter.

Dark Energy, which makes things fall _up_ , is ~70% of the universe. We are almost completely stumped as to what it is and how it works beyond making the universe roomier. We're just totally knackered on Dark Energy.

Any civ that is thinking that seriously thinking about (let alone putting down-payments on) discombobulating planets in order to make more lawns to mow and gardens to weed is _very_ likely to have more than a toehold on Dark Matter and is likely trying to make Dark Energy levitate tequila shots.

And that's just the physics that we know we're missing. K2 civs are probably far more aware of yet more dragons in the mists.

So, concluding (correctly) that since we don't see the IR heat of K2 planet demolitions, that we're alone, is not the best conclusion. We've not a clue as to what the rules of the universe are yet. We can talk about strategy once we learn how the knights and bishops move about the board.

</comment></comment><comment><USER23> My theory is that any advanced civilisation reaches a point at which a vast amount of destructive power becomes accessible to individuals. At this point it becomes only matter of time until that civilisation is destroyed.

The analogy I use is to imagine that every adult human on Earth woke up tomorrow morning with a button on their wrist that could destroy the Earth. How long do you think we would last?

We haven't reached a stage where an individual can create a nuclear bomb, a new kind of super-virus or some other doomsday weapon but I imagine its not an implausible scenario in the future. I think this is kind of a wall that all advanced civilisation may hit at some point.

<comment><USER24> It's not hard to imagine in the near future that having a PhD in biology and access to a moderately equipped lab would grant a person the ability to create super plagues capable of killing most humans.

Couple that with the wide spread nihilism that wants to destroy the world because they can't stand the injustice of life, and it's a pretty good bet our time as a species is limited here.

If I were king for a day I'd do everything I could to get the message out that things are getting better, injustice is shrinking every year, and there is hope.

<comment><USER25> > It's not hard to imagine in the near future that having a PhD in biology and > access to a moderately equipped lab would grant a person the ability to > create super plagues capable of killing most humans.

Pretty sure that's already the case.

</comment></comment></comment><comment><USER26> Does a lion born in a zoo understand it's being held captive by (in comparison) super intelligent humans? When it's tranquilized, does it know this isn't a normal thing for a lion? When the caretaker throws food out or pets it, does the lion have the capacity to think about it in any other way than what it means right now for the lion - food, feels nice, etc?

If there's a correspondingly more intelligent alien species hanging out on our planet with us, would / could we even hope to know?

<comment><USER27> But Lions don't appear to have any abstraction ability, or reflective thought. By that I mean you as a human can imagine yourself thinking about some hypothetical situation, as well as consider what kind of evidence would support a given hypothesis.

I think this might have actually happened (apocryphal?), but just imagine if you took humans from another country and put them in a zoo. They would surely figure it out, based on the evidence at hand.

<comment><USER26> Definitely agree.

Just like how a lion or a chimpanzee wouldn't make a convincing zoo for another lion or chimp, a human could figure out they're in a zoo made by another human.

But when you make a zoo for an animal that isn't on your level, you can figure out what's needed to satisfy it (even if it's really crappy compared to their normal environment).

So if something smarter than us by an order of magnitude or more made a zoo for us, it would be a much more elaborate and convincing zoo, and I'm not sure we'd figure it out.

<comment><USER28> If we are talking super-advanced, it wouldn't even need to be a physical zoo. Just mess with enough of our brains enough to make us not want to do certain things and we'll stay on this rock forever.

</comment></comment></comment></comment><comment><USER29> The article does a good job of explaining some of the numbers, but it's important to remember just how large they are.

To a spacefaring civilization a million years might be the human equivalent of a decade.

The sad truth is that intelligent humans (enough to think and act on thoughts of space travel) have barely existed on the cosmic timeline, and likely won't live long enough to know the answer to whether or not we're alone. Not because of some romanticized fermi gate paradoxical reasoning, but simply because we ran out of time.

<comment><USER30> What do you mean? How is running out of time different from a Fermi gate? Without a gate, why would time run out? The only natural limits are the time limit to colonize another planet, then another solar system, before our earth and sun lose their ability to sustain life.

</comment></comment><comment><AUTHOR> I personally subscribe to the school of thought that interstellar travel is impossible, except through some form of suspended animation or generation ships (which both have its own problems). So no warp/hyperdrives, no wormholes, no shortcuts to travel between the stars. This article dismisses that notion before it even begins, but this is the only theory that fits the currently observed laws of the universe.

<comment><USER31> Even with no FTL, you can still do interstellar travel just fine if you make people live longer, which is being worked on for other reasons already.

<comment><USER32> It's not individual lifespans that are the issue, it's the lifespan of your equipment. If your rocket breaks down in the interstellar void, you have no resources with which to fix it.

And then you need to be able to bootstrap the entire industrial base to build a new rocket at your destination without any help whatsoever aside from what you brought with you. Given the history of interoceanic colonization efforts on Earth, this suggests that the difficulty ranges from "insane" to "impossible."

<comment><USER31> I think thats stil managable, even simply by redundancy and sending fleets of ships. Also 3D printing of replacement parts seems pretty promissing and is already being looked into (there is a basic 3D printer or the ISS).

<comment><USER33> There is, but it doesn't really do anything, right? They printed some plastic toys with it; it's not operations-critical.

</comment></comment></comment></comment></comment><comment><USER34> I think it's time we stop looking for life near other stars and start saving our own. This planet is completely neglected. You want to live on Mars? That should be fun, without a magnetic core. Living underground, like rats.

If you want to know what frontier living feels like, take a week off and stay in one of the Inupiat villages on the edges of Alaska. You'll be climbing up walls in 3 days. And _that_ is a luxurious vacation compared to frontier living on a barely habitable planet. Netflix? Nah, bro. They still have Blockbuster.

</comment><comment><USER35> More likely we really are alone: [http://aleph.se/andart2/space/seti/dissolving-the-fermi- para...](http://aleph.se/andart2/space/seti/dissolving-the-fermi-paradox/)

<comment><USER36> That paper only claims that it is _plausible_ we're alone, meaning the Fermi paradox is only a question, not a conundrum.

</comment></comment><comment><USER37> Fermi paradox. I never liked it.

It presumes too much.

It presumes that technology will advance to the degree that we overcome the speed of light. Not directly, but that's where it has to wind up.

Because no matter how you slice it, it's still four years to Alpha Centauri at the fastest possible speed we know. That means it will be at a minimum 8 years before we know if anything was successful.

And yes, for the travelers, _they_ experience time dilation, but we here on Earth would not. That time does matter. Even with self-replicating Von Neumann probes, they still have to send that information back. That's still going to take time.

How many resources can you dedicate to a bet that's going to take at least a decade to show a return? How many of those bets can you make before you've depleted your resources to the degree that you simply cannot do it anymore?

I think we may find ourselves up against the uncomfortable truth that our cosmic range is rather limited.

<comment><USER31> IIRC Fermi paradox does not expect FTL - a locust style colonization effort should be able to settle the whole milky way quite quickly (couple hundred thousand years) even with not very fas sub light travel.

<comment><USER37> Like I said, not directly, it doesn't, but once you start digging down, you're going to need that.

A couple hundred thousand years is quick on a cosmic scale, but we, as a species, have never undertaken any project on that scale ever. No species has that we have evidence of.

Any sublight travel is a one way trip with almost no hope of ever knowing it was a success by the people back home. No one funds that. And I don't blame them. There is no return in any fashion for the people who remain. And little to no return for anyone who starts the journey. The only thing you can possibly satisfy is some minor curiosity.

Travel to Proxima Centauri at the current highest speed we've sent probes into space would take over 80,000 years. If you double that speed. It will still take over 40,000 years.

So, cosmically, the time scale is short. And compared to light, the speed needed is slow.

But we're not light, are we? We don't exist on cosmic scales. I'm not concerned with the theoretical limits of physics. I'm more concerned with the practical limits of us.

<comment><USER38> Don't be; 'we' won't be doing it. These are evolutionary/revolutionary timescales; how many millenia away do you think general artificial intelligence is?

<comment><USER37> First, I think what we're searching for isn't intelligence so much as consciousness. So I'm going to treat general AI and consciousness as pretty much the same thing.

Considering we don't exactly know what consciousness is or what it means to "be intelligent", I have absolutely no clue how long it will take. But unless there is something I'm unaware of, I do think that we're approaching the problem from a wrong direction.

Think about it like this, we know that intelligence/consciousness is an emergent property of a lot of life on this planet. Including some life that we previously didn't consider aware in the traditional sense. Plant life may have some sort of intelligence/awareness.

When an artificial intelligence can express a genuine desire to avoid termination, we'll know we've gotten it.

Then again, do we even express genuine desires? Or are we simply inefficient meat computers responding in predictable ways to external stimuli?

So the question is whether or not general AI is even possible for us to make.

And then the assumption is that this general AI will be able to plan on the cosmic scale. But why? First, what's the life span for most electronics at this point? That factors into desire. What happens beyond our death is only of academic concern to us. To assume it won't factor into their decision making process is just speculation.

And if you presume we'd have programmed this general AI with the desire, well, it's not really a general AI, is it? We've robbed it of a decision. We've taken an entire forest of decision trees from it. It can't not choose to colonize the stars.

Then you're also making the assumption that general AI won't come to the conclusion that colonizing the stars is an inefficient use of resources. General AI doesn't really change the problems with the Fermi paradox, it only seems to add new problems.

<comment><USER38> >First, I think what we're searching for isn't intelligence so much as consciousness. So I'm going to treat general AI and consciousness as pretty much the same thing.

That's not how I think about it at all. I think you're underestimating how alien AI could be to us, in general. I.e., I think you're anthropomorphising it unnecessarily.

There's an idea called the orthogonality thesis, which says: The intelligence of an arbitrary agent can vary independently of its goals.

Here, I'm using intelligence to mean just the ability of an agent to generate/evaluate/execute plans to further its goals. A modern chess AI on modern hardware is more intelligent than one from the 1980s. In principle, you could have any arbitrary utility function attached to any level of intelligence.

This idea was brought up because often, when people heard about the paperclip maximiser (an agent that tries to maximize the number of paperclips- and thus wants to take apart everything in its lightcone and turn it into paperclips), they said: "But why would something so clever do something so stupid and pointless? A superintelligence would surely realize it was being stupid and decide to do something smarter."

But there's no reason to think this! When you take away the agent's goal of maximising paperclips, there's no perfect platonic ghost of consciousness left! The paperclip maximiser, as defined is _just_ an algorithm that predicts the future, looking for actions that maximise paperclips, and executes them. Given unbounded compute power, it can just look through arbitrarily many counterfactual simulations of the future given different plans, pick the plan that maximises the number of paperclip-like structures in the universe, and execute it. The rest is implementation details, given we don't have unbounded computing power, but the point is such a system doesn't need to be conscious to be powerful.

If you have an AI without a utility function, you don't have an AI. 'General intelligence' just means the AI's computing/reasoning/versatility power, in a vague sense. It has nothing to do with whatever particular utility function an agent might be trying to maximize.

The paperclip machine doesn't 'want' to colonize the stars; it's just a system that will do that if it can, because tautologically, it's a system that tries to turn as much as it can into paperclips.

I don't really think there is a Fermi 'paradox'. We don't have solid priors on how often agents arise in the universe. The fact there aren't any visible aliens should either just lower our estimates of how likely life is, or maybe there's some sort of anthropic principle argument to be made here where we probably wouldn't observe a universe where aliens come to visit, because in nearly all possible universes where intelligent life survives and goes from star to star it just eats all the stars very quickly on astronomical timescales or something, such that the chances of intelligent agents like us arising while there's visible evidence of other agents is incredibly slim.

<comment><USER37> Like I said, we don't even _know_ what consciousness _is_.

To say there is a platonic consciousness is kind of saying you know what that looks like. And to say that you could grant something an intelligence capable of solving the problem of colonizing the stars while also denying it the ability to choose its own goals is an assumption I'm not willing to grant.

In other words, there _is_ "a reason to think this!" We are that reason. Other life on this planet is reason to think this.

</comment></comment></comment></comment></comment></comment></comment><comment><USER39> I find it strange that the author thinks that Dark Forest theory is implausible. It strikes me as the simplest of explanations.

Granted Cixin Liu stretches physics into all sorts of implausible places, but it does make a strong argument for the theory.

[https://www.goodreads.com/book/show/48838110-three-body- prob...](https://www.goodreads.com/book/show/48838110-three-body-problem- boxed-set?ac=1&from_search=true&qid=cqWNAtigNA&rank=1)

<comment><USER40> I loved those books, but the dark forest theory doesn't make sense. Given a dangerous universe it would make sense for a civilization to try to communicate with other civilizations to create alliances for mutual safety.

The civilizations that are able to forge alliances will tend to out-compete lone wolves.

Liu assumes that it is somehow a lot easier to wipe out a civilization than communicate with it, and that for some reason your civilization has to decide to wipe out another civilization without communicating with it.

<comment><USER41> > Liu assumes that it is somehow a lot easier to wipe out a civilization than > communicate with it...

This may be true, though. We struggle to effectively communicate with creatures on our own planet available in real-time, like dolphins and elephants, who appear to think and have language of sorts.

Launching some relativistic sand at another planet may well be a lot easier.

<comment><USER40> We seem to communicate pretty well with dolphins, elephants, and other animals. Consider trainers who work with these animals on a daily basis and have rich and productive relationships with them.

<comment><USER41> We can explain "go press that button" or "lift your leg" fairly well. We can't, as yet, put a dolphin through something like an elementary school level education.

</comment></comment></comment></comment></comment><comment><USER42> Well, even if we're not alone, we must acknowledge that someone had to be first to develop the ability to travel through the cosmos. It may actually be us.

<comment><AUTHOR> We already have that ability. It's just that this travel is insanely slow and requires the energy levels that we can't easily produce in those timescales. It is quite possible (I would even say likely) that any faster travel is not very viable, and it might never be possible to make any kind of FTL engine.

<comment><USER43> We don't have yet the communication technology for anything far from our system.

</comment></comment></comment><comment> radford-neal The simulations in this article are compatible with the more abstract analysis in my paper at [http://www.cs.utoronto.ca/~radford/anth.abstract.html](http://www.cs.utoronto.ca/~radford/anth.abstract.html) (see Section 7).

The brief summary is that we observe two things: (1) we exist, with the full set of memories we have, (2) these memories don't include any evidence of other intelligences (I'll assume - readers who think they've ridden on UFOs can draw other conclusions).

The existence of our particular civilization (in all its detail) is more probable if intelligent life is more probable in general (assuming one dismisses arguments about infinite universes containing all possibilities, so you can never conclude anything from anything).

But if intelligent life is generally more probable, it's more probable that we have seen other intelligent life, contrary to observation.

So the most likely situation given what we observe is a compromise - intelligent life is fairly likely (explaining our existence), but not really likely, or at least not really likely to explore other stars (explaining why we haven't seen any aliens).

One unfortunate possibility is that intelligent life reaching our technological level is common, but getting to the level of colonizing the galaxy is uncommon. But that needn't be highly likely. It's also possible that there's other intelligent life out there not far away, in which case it may well be within our ability to detect it with a bit more effort. That's what one would conclude from this article as well.

</comment><comment><USER44> I have a somewhat nihilistic theory around the Fermi paradox. What if all intelligent life annihilates itself before reaching high enough technical proficiency to achieve widespread inter-planetary travel (or time travel). The idea is that intelligent life emerges from the process of evolution (natural selection) where the stronger survive. But that leaves you with people who have the tendency to kill each other and themselves off. As the technological ability to completely annihilate ourselves increases the probability that it will eventually happen goes up over time. As technological prowess increases and population increases, intelligent species eventually destroy themselves by using up all their resources or ruin the planet with climate destruction before achieving inter-planetary capability. Similar to how yeast will reproduce until they all kill themselves off in their own waste product (alcohol). It is possible that this is a universal axiom, hence intelligent life does not spread across the galaxy. I know this is a depressing thought but it's an idea that has haunted me once it occurred to me.

<comment><USER45> The models attempt to encapsulate this issue through the variable of how long a civilization lasts. As easy as it is to imagine civilizations similar to us, it's equally easy to imagine others where other variables prevent the intense egoism we evolved as a species. Or worlds where competition is less fierce perhaps. Etc..

Either way I find it fascinating that we could be living in what is essentially the rural area of the galaxy.

<comment><USER30> With a sample size of 1, there is no way to estimate the possibility of a species fundamentally unlike us becoming spacefaring.

We can count stars pretty well, but we can only barely estimate the probability of an earth-like planet existing around a star and forming cellular life.

</comment></comment></comment><comment><USER46> It bothers me that the authors' assumptions are so controversial and that they hide them in the middle of the article.

In the simulations the authors are using, civilizations have lifetimes, meaning that all of them end after a while. And that simply isn't supported by events. Technological civilization has never vanished even from our little one-planet civilization. Polities do decline, but there is usually someone there to pick up the pieces. In an interstellar civilization there would be more recovery opportunities: interstellar visitors who arrive to see why a collapsed planet went offline.

The authors of this piece are asking us not just to assume that simultaneous disaster is possible on ten, a hundred, or a thousand planets. They are asking us to assume that it happens to every single time a civilization has achieved interstellar travel, and that it has been happening for the last ten billion years.

Simultaneous catastrophes on thousands of worlds affecting millions of species for billions of years? Life arising only once could easily be the more plausible option.

<comment><USER47> > Life arising only once could very well be the more plausible option

Indeed I feel like coming to this conclusion is something that the authors - and most of us rationalist types - do not _want_ to come to.

Because if you accept that hypothesis, then it follows as a consequence that an alternative view of the world makes a lot more sense: what if, rather than living in an emergent, random universe where life sprouts up everywhere, hundreds of billions of times, but somehow _always_ disappears before we can ever observe it outside Earth, we are instead living at the center of a universe where we are the sole intelligent species that ever existed? In that system of the world, the universe is being directed by beings existing outside its bounds - gods. A simulation created and managed by uncaring observers - <USER3> hypothesized by the likes of Elon Musk? Or a benevolent God in the Judeo/Christiano/Islamic tradition?

The truth is that this alternative is being rejected a priori, indeed not even acknowledged, by the authors of the article or most people in this thread, because it is an affront to their core beliefs, not through pure logical reasoning.

<comment><USER48> > The truth is that this alternative is being rejected a priori, indeed not > even acknowledged, by the authors of the article or most people in this > thread, because it is an affront to their core beliefs, not through pure > logical reasoning.

I think it isn't acknowledged because it is inconsistent with literally everything we have learned about physics and the universe, and even if it were true, as you said, they are outside this reality and don't care. They set the simulation parameters, and then walked away, so they are irrelevant.

If however, you point to something like miracles occuring in our reality to back up the "gods" view, then you aren't really having the same discussion as the authors.

</comment></comment></comment><comment><USER49> I don't understand why ufological data is systematically ignored. This leads to biased reasoning.

<comment><USER50> I agree. To talk about the possibility is to commit scientific suicide. Even cautiously talking about the topic immediately outs you to others as a crackpot. I think it's undeserved. Especially when we are now seeing just how many habitable world's are out there. It seems plausible that we have been visited by curious extra terrestrial civilisations. The bizare patents coming out of the US navy suggest to me that no one knows where these things are coming from, if they are real.

<comment><USER51> > It seems plausible that we have been visited by curious extra terrestrial > civilisations.

no it doesnt. It seems increasingly implausible

<comment><USER49> How do you justify this claim ?

</comment></comment></comment></comment><comment><USER52> I see two alternatives, each sufficient:

1\. Expansionist civilizations eventually encounter another one, and reliably obliterate one another. (Note, this is not "Dark Forest": it requires no long- lasting structure of any kind, just the occasional chance encounter that turns out badly.)

2\. Expansionist civilizations find goldielocks planets both unnecessary and limiting, and just leave them the hell alone. They probably mostly use Neptune-like planets, when they have a use for a planet at all. Maybe they are at "our" Neptune right now, and have not contacted us, because why bother? We're "made out of meat". <[https://www.mit.edu/people/dpolicar/writing/prose/text/think...](https://www.mit.edu/people/dpolicar/writing/prose/text/thinkingMeat.html>)

</comment><comment><USER53> This brings to mind Dr. Greer and the Sirius Disclosure project [0]. The first documentary, Sirius, is available on YouTube [1] and the second documentary, Unacknowledged, can be viewed on Netflix.

To be clear, I'm not sure if I entirely believe in all of this myself. However, I don't regret watching any of it. At the very least I got some inspiration for short stories/screenplays.

[0] - [https://siriusdisclosure.com/](https://siriusdisclosure.com/) and [https://www.youtube.com/channel/UCC6B4Y0oFACv9QBlf0ebBcg](https://www.youtube.com/channel/UCC6B4Y0oFACv9QBlf0ebBcg)

[1] - [https://www.youtube.com/watch?v=5C_- HLD21hA](https://www.youtube.com/watch?v=5C_-HLD21hA)

</comment><comment><USER54> One thing I fail to see mentioned here and in such articles is the complexity of colonization. We are falling in the trap of "idea == profit". A lot needs to be done, and can go wrong, between both.

Some examples I am thinking of, and I am certain people will have more... All are compounded by the LY distances between colonies and whatever home is:

\- Terraforming - It would be the exception that new planets are 100% hospitable to a specific species. How long to properly terraform, and then how long before the can get to a point where they can launch a new sub-colony? Need proper population, technology and resources.

\- Culture drift - how long can the colony and home share the same culture, with same values and objectives?

\- Political drift - Imagine you are part of a colony, with "home" some 4 LY away. How long before you will want to have full autonomy, specially given the distance?

\- Cultural and political factions - Is it possible that individuals in the colony have different objectives, resulting with political infighting or open war? What would then be the impact on the colony?

\- Protection - Depending on technological advancement, how can a colony protect itself from external rogue elements (big warship gone rogue, pirating the colonies for resources?)

For sure, many of these things depend on the type of species colonizing its region, how much sentience and free will they have. I also assume they haven't solved FTL travel!

</comment><comment><USER55> This is article went off the rails when it talked about evidence for past civilizations on Earth being undetectable:

> The only real evidence after a million or more years would boil down to > isotopic or chemical stratigraphic anomalies—odd features such as synthetic > molecules, plastics or radioactive fallout.

Civilization on the scale such as ours creates huge waves of extinctions in the planet's species leaving lots of evidence easily available for us to see that it happened.

In addition we've affected the Earth's atmosphere with our carbon emissions and that's going to leave evidence behind as well that will last a very long time.

Also, all that easily accessible oil that we've been using to power our engines would not exist, because nobody is going to be leaving such an abundant and easy to use source of fuel around. The oil and gas we use took tens and hundreds of millions of years to form.

Finally, and not least of all, the quoted paragraph mentions radioactive fall out, but any radioactivity would be blatantly obvious unless this civilization used none of it. There would be a very clear indicator in our dating methods of any radioactive activity in the past.

I think it's safe to presume that instead of some past civilization that didn't use the most abundant natural source of energy around, didn't make use of nuclear energy and somehow managed to leave the species record clean it simply didn't exist. I don't feel like it takes more than a few moments to just realize how unlikely that take is and shouldn't have been included in the article.

<comment><USER56> You might find the the paper [1] and HN submission interesting. I believe it addresses every concern you raised, and comes to the opposite conclusion.

[1] [https://fermatslibrary.com/s/the-silurian-hypothesis- would-i...](https://fermatslibrary.com/s/the-silurian-hypothesis-would-it-be- possible-to-detect-an-industrial-civilization-in-the-geological-record) [2] [https://news.ycombinator.com/item?id=21840320](https://news.ycombinator.com/item?id=21840320)

</comment></comment><comment><USER57> What's the point of settling on planets if you can sustainably develop anywhere in space, which I think is within the reach of any typical space- faring civilization?

<comment><USER31> I guess, you can do both. Well unless you want to use the mass of the planet for a more efficint purpose, eq. habitat swarm.

</comment></comment><comment><USER58> On Earth, there have been previous life-forms which have died out, there have been more or less intelligent life-forms which have died out (various dinosaurs and exhausted branches of hominids etc.), there have been previous civilizations with varying scientifical/technological achievements; but there has never been a species on Earth which has created a civilization as advanced as humans have.

So, we are the first ones to reach this point on the Earth. Not the first ones ever, but first ones to get this far.

If we assume the patterns of evolution observed on the Earth are nothing specific to Earth and they repeat throughout the Universe, there are/have most likely been life-forms (simple and complex) of varying degrees of intelligence, as well as civilizations of varying degrees of technological advancement.

However, since we apparently see absolutely no trace of anyone else, either they failed to successfully bootstrap their colonies outside of their home planet/moon, or we got here first. It's unlikely, and absence of evidence is not evidence of absence, but someone has to be the first. Maybe it's us, from our little blue planet.

<comment><USER59> > but there has never been a species on Earth which has created a civilization > as advanced as humans have.

It's an interesting to think about what traces an industrial civilization like ours would leave behind if we were to be wiped out tomorrow. Most evidence would be gone in a few thousand years. Wait a million and it would be almost like we were never here.

[https://www.theatlantic.com/science/archive/2018/04/are- we-e...](https://www.theatlantic.com/science/archive/2018/04/are-we-earths- only-civilization/557180/)

[https://news.ycombinator.com/item?id=19707426](https://news.ycombinator.com/item?id=19707426)

Never say never :-)

</comment></comment><comment><USER60> I am intrigued by the simulation theory. That we as a species has reached a certain level of advancement to simulate a reality and experience it; or we may just be npcs or temporary programs for another intelligent race in this simulation.

We could also be a zoo/prison planet far into enemy territory. Currently being experimented and observed. Hybridization in order to infiltrate our actual civilization that's located elsewhere.

</comment><comment><USER61> Perhaps slightly off topic, but the title reminded me of this picture I took a few years back.

[https://www.flickr.com/photos/earlvontapia/16211171391](https://www.flickr.com/photos/earlvontapia/16211171391)

I really wanted more of the Milky Way to pop out, but was hard given the sensor and the lens I was using.

</comment><comment><USER62> (1) Biological life colonizing other planets? The individual beings would not live long enough to make the journey. So, would have to have reproduction of generations during the trip, and that means one heck of a big spaceship. Then for any of the motivations, I would be easier just to stay home.

(2) Sending self-reproducing robots? Why? What's the motivation? E.g., why should I consent to spending big tax bucks to send robots out that would need millions of years to have any effect back on earth? I won't.

Okay, there is the scenario that a planet is ready to die, and the beings want to move to a new land. Again, for anyone alive, what is their motivation? That is, either stay home and wait for, say, the star to nova or just die on a long space trip? Just stay home; as bad as a star nova would be, just stay home.

One more scenario is that fast space travel is possible but uses physics we don't understand and, thus, can't detect.

</comment><comment><USER63> I guess the primary argument to this is the number of stars, and the amount of time the universe has been around... but like the universe is _very young_. Our universe currently has an expected lifespan of like a trillion years. That is to say, if it's lifespan is 100 years, it's currently a ~13 month old infant.

There is a supremely _good_ chance we, humans, are and will be the creepy ol' species we write movies about that has colonized stars and existed "since the beginning."

Should we ever successfully make it off this rock that and to another star that is...

It's fun to think about too, how will our species handle billions of years of separation at distant ends of the universe? Will we use gene therapy to ensure our "look" and aesthetic, or will culture and evolution be unpreventable yielding humanoids nearly unrecognizable to our current form?

</comment><comment><USER64> I would be especially careful of arguments that end up like "it's a great opportunity for humankind as no-one else is there to compete for the next million years"

It might be true. But the most likely thing we will find on the nearest habitable planet is a legal writ and summons.

</comment><comment><USER65> The boring answer is that the initial origin of life depends on a sequence of extremely improbable chemical reactions (even given the prior existence of the most favourable possible "organic soup"), and there is no other life of any kind in the observable universe.

<comment><USER66> life arose on Earth immediately after it cooled down and Earth then was nothing like what it is today. The organic chemical reactions are extremely probable not improbable.

</comment></comment><comment><USER67> It seems to me that the millions of events that happened in order to get to where we are now (alive on a rocky, water and oxygen-filled planet, in the Goldilocks zone of a healthy star) were sequential in nature and they took a finite amount of time to occur.

Assuming that there was A Beginning, where everything started at the same time, wouldn't the steps to get to where we are in this process take about the same time for everyone else? Meaning that if there are other civilizations out there, that they'd more or less be as advanced as we are? Which is pretty sophisticated in certain areas at home, but not yet super capable in the long- distance human space travel department.

Not a scientist, just thinking out loud the thought I had reading the article.

<comment><USER68> Perhaps, but even tiny variances could cause shifts in the timeline of thousands or millions of years, which would be a blink compared to the age of the universe. Look how far we've come in the last 200 years. Imagine a civilization that is only 10,000 years ahead of us.

<comment><USER67> I'd love to see what the iPhone 10,000 ends up looking like

</comment></comment></comment><comment><USER69> I think big filter is plausible where as we advance in tech, the probability of us accident using to kill off everything increases. It starts with nuclear weapons and then maybe later mini black holes, etc.

</comment><comment><USER70> _(First wears tin-foil hat)_. It may be more likely that we are under _observation_ and a mature inter-stellar space faring alien civilisation has _commandments_ not to interact or interfere with the _primitive natives_. They occasionally mess up and then the _UFO 's_ are seen. But their propaganda department clears the mess up.

</comment><comment><USER71> From our perspective, even if another species had colonized millions of stars, it would still be like looking for dust on a mountain.

</comment><comment><USER72> The theory of this article is that we are not just in a gulf of space but also a gulf of time. We are after all on the relative outskirts of our galaxy, vastly isolated from other civilizations. Perhaps one day we'll be the ones knocking on our neighbor's door to say hello!

</comment><comment><USER73> Previous discussion on the possibility (mentioned in the article) that an advanced industrial civilization existed on Earth: [https://news.ycombinator.com/item?id=21840320](https://news.ycombinator.com/item?id=21840320)

</comment><comment><USER74> Afaik, nobody has debunked the Borra paper, so we already found them.

Discovery of peculiar periodic spectral modulations in a small fraction of solar type stars

[https://arxiv.org/abs/1610.03031](https://arxiv.org/abs/1610.03031)

<comment><USER75> This study fails to replicate Borra's results.

[https://iopscience.iop.org/article/10.1088/1538-3873/aaeae0/...](https://iopscience.iop.org/article/10.1088/1538-3873/aaeae0/meta)

<comment><USER74> Drat! Thanks

</comment></comment></comment><comment><USER76> I think if you look at patterns in nature this has to be possible. Surely there are some remote ant colonies that don't have interaction with anything outside the natural resources that sustain them.

</comment><comment><USER77> There are arguably too many unknowns to do much more than speculate.

But let's say there's some other planet with comparable technology. At what distance could we detect its routine radio emissions?

<comment><USER78> No more than 1000LY, per this article:

[http://www.setileague.org/askdr/howfar.htm](http://www.setileague.org/askdr/howfar.htm)

i.e. 1% the diameter of the Milky Way:

[https://www.universetoday.com/21998/the-diameter-of-the- milk...](https://www.universetoday.com/21998/the-diameter-of-the-milky-way/)

<comment><USER77> Thanks.

I wonder what percentage of the sky those larger SETI telescopes have looked at so far. I tried searching the SETI site, but had no luck.

But anyway, that's a small enough volume that it could plausibly be temporarily dead or quiet, as TFA argues.

</comment></comment></comment><comment><USER79> Fascinating theory, but we aren't Pitcairn Island.

> Why, then, have we found no irrefutable evidence of aliens visiting Earth?

We have evidence, it just gets "refuted" for psychological reasons. The Fermi Paradox is a Rorschach test, and has nothing to do with reality.

In reality, humans in every culture have recorded incidents of communications with non-human intelligences.[0]

In reality, the Brazilian Military has gotten much less coy about UFO phenomenon in recent years and has started declassifying documents. Their overall conclusion is that, whatever they are, UFOs are real, pose no national security threat, and should be researched and discussed by society at large, with some urgency.

Here's a fascinating lecture by a Brazilian UFO researcher about the overall situation in Brazil and he describes three encounters that are known to have government involvement (so the researchers know what to ask about, in these cases.)

"Operation Saucer - UFO military encounters in the Brazilian jungle" [https://www.youtube.com/watch?v=ThkmRsEBOY0](https://www.youtube.com/watch?v=ThkmRsEBOY0)

> In 1977, numerous UFOs were seen in the Brazilian city of Colares, Pará. The > UFOs fired light beams at people, causing injuries and sucking blood from > 400 witnesses. After a rise in local concern, the mayor of the city > requested help from the Air Force. Operation Saucer started, during which > numerous photos were taken and testimonies collected. Operation Saucer is > just one of the compelling cases which A. J. Gevaerd, editor of Brazilian > UFO magazine, talked about in his latest lecture in Copenhagen, paving the > way for complete Disclosure in his country. Kudos to Exopolitics Denmark for > setting up their excellent annual conference at the Danish National Museum > on September 26 in Copenhagen!

The first case involves thousands of people, living on an island in the Amazon, who were attacked by UFOs over a period of several years (1975-1977 IIRC). Flying cans with visible pilots were shooting people with bending "light" beams and sucking up their blood. It got so bad that thousands of people evacuated and the Brazilian Army sent in a unit to find out what was going on and try to make contact. I won't spoil the rest of the story here.

To me, the strangest thing I can see is the question: Why would people (aliens or humans) who have evidently advanced technology go around attacking poor villagers to _suck their blood_!? WTF?

[0] (I myself once attended a event at an airport hotel at which some purple telepathic space dolphins were guest lecturers. FWIW, their basic TL;DR: was "Be nice to each other." Aliens were attending underground raves in Seattle in the 90's.)

<comment><USER41> > pose no national security threat

> sucking blood from 400 witnesses

Pick one.

<comment><USER79> Sucking blood from 400 people posed no _national_ security threat.

Don't get me wrong, I'm not trying to trivialize what these folks went through. I'm pointing out that the threat was in a small, localized area.</comment></comment></comment>


Crony Beliefs - <AUTHOR> http://mindblog.dericbownds.net/2017/03/crony-beliefs.html <comment><AUTHOR> I posted this summary, instead of the actual article, because the original is quite wordy, and a summary seemed more useful for an initial read.

Here's the article, fwiw:

[http://www.meltingasphalt.com/crony- beliefs/](http://www.meltingasphalt.com/crony-beliefs/)</comment>


Show HN: Get RSS/Atom Feed Updates Delivered to Your Inbox - <AUTHOR> https://www.feedsub.com?hn <comment><AUTHOR> I'm making Feedsub to help manage my content consumption life. The email inbox is one of the most powerful tools at our disposal, and ideal for getting content updates from across the web. It's a simple service, but one I believe that fills an important niche!

Coming in the future is the ability to create keyword filters and closer integration with popular web services. You'll soon be able to do subscribe to updates such as:

"Send me updates related to AI from IndieHackers"

"Send me the latest from Product Hunt (except iOS apps)"

"Tell me when I'm mentioned on Hacker News"

Please feel free to send your feedback to email@example.com.

Happy feed-reading guys!</comment>


Why do exams test un-taught material? - <AUTHOR> I'm taking an online mooc for a comp science class. I feel that I've grasped the material in the lectures and have passed all the quizzes and problem sets without issue, however the midterm exam introduced many obscure twists to the topic that were never covered in the lectures. I recall this happening a lot when I was in college, and there must be a reason why. Isn't the goal of an exam to test one's understanding of topics covered in class? To all educators out there, why introduce new stuff in exams? <comment><USER2> My guess: To test whether you understood the teachings enough to apply them properly to a new situation vs. simply memorizing the correct answers to the lecture problems.

</comment><comment><USER3> Such questions may seem off topic, but usually require application of concepts taught in the course. Look deeper for an implicitly given challenge which can be solved with course material.

Despite my comments above, there are a few tools pretending to be educators who pull test items out of their asses, making sense only in a twisted mind.</comment>


Corrupting the ARM Exception Vector Table - <AUTHOR> http://doar-e.github.io/blog/2014/04/30/corrupting-arm-evt/ <comment><USER2> Having this page be kernel-writable is just asking for trouble. In days of yore (the Apple Newton) these vectors were in ROM.

On the Newton, our memory management guy (hi, Bob!) went the extra mile and made sure that MMU mappings weren't mapped; you had to run a piece of code that was mapped in the same location physically as well as virtually that turned off the MMU, frobbed the page tables, and then turned translation on again. The theory was that we kept patches in battery-backed RAM, and we wanted to dramatically reduce the chance that they could be over-written, even by the kernel.

Not really sure the extra complexity was worth it, but I never heard of a Newton losing its patches short of utterly exhausting the backup battery. (It probably helped that we weren't under active attack, pretty much ever :-) )

<comment><USER3> The Newton had a lot of great tech. Thx for posting. I really liked their clever hardware protection system that was done in a single address space style.

</comment></comment><comment><USER4> Good write up, only gripe is that the font is unreadable.

</comment><comment><USER5> The article doesn't look to be using very recent Linux.

Newer ARM variants don't have their vectors at that address.</comment>


Cryptocurrency Analysis with Python – Buy and Hold - <AUTHOR> https://romanorac.github.io/cryptocurrency/analysis/2017/12/25/cryptocurrency-analysis-with-python-part2.html <comment><USER2> Unless you can include the _complete irrationality_ of the users fueling the crypto bubble to get rich into the statistical model, any statistical analysis of those prices will be misleading.

Traditional historical trend analyses of stock prices assume the market is _somewhat_ rational. (but not 100% efficient, which is where money can be made)

<comment><USER3> if Gold can be irrational for 2k years, I don't see why not bitcoin can't, the only think gold has going for "longer history", yet HN folk love to say "past performance are not an...bla bla", yes it also has the 5% - 10% industrial use, but bitcoin has that too by being able to transfer it without third party, so will also not go to zero because will be useful as transfer of value.

<comment><USER4> Gold has a price floor because it has some industrial utility and is useful for making jewelry.

All that has to happen to destroy bitcoin is a flaw in the implementation.

Seriously, look at OpenSSL and tell me the same issues aren't possible in bitcoin.

When did we get so trusting of software that we decided it'd be a good idea to base currency on a distributed algorithm?

<comment><USER5> The project can always fork if major issues are found.

Bitcoin is very very far from a perfect solution, but it is a solution to many problems currencies have.

<comment><USER6> Given how hard it is for the community to do something as simple as increase the block size a tiny bit, I'm not confident that a fork could fix such a problem.

</comment></comment></comment></comment></comment><comment><USER7> At our local Chicago Python User group chapter (chipy.org) one of the organizers of the Financial Group did a similar analysis. HODL is extremely hard to beat if not impossible.

See [https://github.com/Chipy- Finance/CryptoTechnicals/blob/maste...](https://github.com/Chipy- Finance/CryptoTechnicals/blob/master/FinSIG%20Dec%202017%20-%20Technical%20Crypto%20Strategy.key)

[https://github.com/Chipy- Finance/CryptoTechnicals/blob/maste...](https://github.com/Chipy- Finance/CryptoTechnicals/blob/master/Buy%20and%20Hold.ipynb)

There is more in the github directory also.

<comment><AUTHOR> thank you. Gonna look at it

</comment></comment><comment><USER8> I ran some tests of my own with simulated automated trading strategies over the past few years of historical Bitcoin price data. I used a genetic algorithm to encode a range of time parameters for MACD, along with different trading triggers and amounts. After a day or two of running it against a huge number of permutations and generations optimized for highest overall return, I came to a similar conclusion: the fittest configurations could do fairly well in automated trading (the more active ones were highly sensitive to trading fees [which were simulated] and market depth [was not simulated]), but over the span of more than a few months, a simple buy and hold strategy produced better returns in almost any time window.

<comment><USER9> Not to be rude but I stopped reading at "MACD". TA is not the go-to strategy in stock trading for a reason. Indicators like MACD, RSI, Bollinger Bands etc re-paint a lot. So the perfect signals everyone sees on the charts are, for the most part, are just "profitable system" mirage.

<comment><USER8> Thanks. The conclusions may be obvious to experts in algo trading (and I heard similar things about the problems of TA for stock trading prior to doing this), but it was educational for me to go through the exercise because (1) it confirmed to me that the crypto markets behave similar to other markets, and (2) it helped me understand exactly where and how a technical indicator like MACD falls short for making trade decisions.

Before trying it myself, I was somewhat skeptical when reading about how these indicators don't work well. The overlays on charts always _looked_ like good buy/sell indicators, so I didn't really understand why they couldn't make for a good algorithm. Only after trying it myself did I gain insight as to why they don't actually work so well.

I guess it's better to learn the hard way than to learn the hard-and-painful way with real money ;)

<comment><USER10> > _Only after trying it myself did I gain insight as to why they don 't > actually work so well._

Would you care to elaborate on which indicators you tried, and what happened?

<comment><USER8> From my experience with MACD specifically, it basically came down to the fact that with longer periods (or less sensitive thresholds), you lose out on most of a price swing by the time your trigger fires, and with shorter periods (or more sensitive thresholds), you end up making a lot of trades that don't move the needle (can also rack up significant fees if you aren't careful). You can find something reasonable in the middle, but by doing so, you're decreasing both risk and potential returns.

There are at least two other important considerations apart from the indicator itself: how to actually execute effectively with limited funds (when your trigger fires, do you trade everything you can, only a certain percentage, or some variable amount based on technical factors? - that's an entirely separate algorithmic rabbit hole); and even if you do find a good algorithm and it performs great in backtesting historical data, it's almost always harder to achieve the same results in real market conditions (it's difficult to simulate the spread and dynamics of limited market depth).

</comment></comment></comment></comment></comment><comment><USER11> This may be a bit pedantic, but the phrase the author uses in his disclaimer "Experts agree that cryptocurrencies are a bubble." bothers me because it's kind of misleading.

The actual fact at hand is ~96% of economists think that the crypto market has been subject to a massive speculation bubble as of November. While that's sort of close to Roman's disclaimer, there is some nuance that ought to be given, since a) 4% of professionals dissent, and b) the question asked of economists had a temporal element to it, and they might have answered differently if the market hadn't tripled in value in as many months. It's the difference between 'the housing market is in a bubble currently', and 'housing is a bubble'.

<comment><USER12> _there is some nuance that ought to be given, since a) 4% of professionals dissent, and b)_

That's roughly the same % of professionals that I've heard dissent about global warming, yet dissenting about _that_ will get you labeled as stupid and/or corrupt. So what makes it worth calling out for nuance here?

</comment></comment><comment><USER13> Don't work with closing prices for statistical analysis. Work with returns (really log returns). This would have simplified some of the code, and made the plots in the same units rather than requiring separate axes.

More detail: [https://quantivity.wordpress.com/2011/02/21/why-log- returns/](https://quantivity.wordpress.com/2011/02/21/why-log-returns/)

<comment><USER14> What do you mean by those plots currently have different units? Don't they consider the price in dollars as the unit?

<comment><AUTHOR> They have the dollar as a unit, just y-axis scale is different. For BTC is from $4000 to $20000 and for LTC is from $50 to $350. This is a useful technique to check if curves move together or not.

</comment></comment></comment><comment><USER15> It's an open secret that "buy and hold" is hard to beat.

This is the reason why ETFs and other unmanaged asset options have become so popular in recent years.

But that insight is not new. The phrase "time in the market beats timing the market" goes way back and also popular stock market participants like Buffet or Kostolany have been saying this for decades.

With regards to cryptocurrencies, we are seeing in a condensed time frame the same development that for example the stock market went through. Cryptocurrencies might become a new asset class but that doesn't mean that it works financially differently than the other asset classes. So it should be no surprise that the same trading strategies end up being the most profitable.

</comment><comment><AUTHOR> My next step is to implement strategy testing. I would like to end this series with a classifier that predicts buy or hold.

Follow me on Twitter to get the latest updates: [https://twitter.com/romanorac](https://twitter.com/romanorac)

<comment><USER2> A classifier that _flips a coin_ would probably have higher accuracy.

<comment><USER16> Give the coin a bias towards long and you've got a winner!

</comment></comment></comment><comment><USER17> I think you meant HODL.</comment>


ZimCode.IO: Importers with free progress reporting - <AUTHOR> https://github.com/Zim-Code/IO <comment><AUTHOR> Feedback, ways to clean up code, things to improve on, etc. all welcome! Trying to learn and better myself.</comment>


Discusslr Review - <AUTHOR> http://www.matthewreichardt.com/discusslr-start-a-discussion-share-the-link/

<comment><USER2> Thanks for the review. The markdown editor is a great suggestion and will be implemented ASAP.</comment>


Secrets of the Nexus One's screen: science, color, and hacks - <AUTHOR> http://arstechnica.com/gadgets/news/2010/03/secrets-of-the-nexus-ones-screen-science-color-and-hacks.ars

<comment><USER3> This article is neat about the engineering/marketing (seriously, it's clear and direct and has useful pictures; that part is highly recommended). The part about vision and color is pretty sloppy though.

This sentence:

> _"The reason this trick works is that rods are 20x as dense as cones in the > retina, meaning the eye has approximately sqrt(20)=4.5x the spatial > resolution in detecting intensity or luminance transitions compared to > detecting color or chrominance transitions."_

... is simply false. The reason that we see lightness differences with better spatial resolution has (almost) nothing to do with numbers of rods vs. cones (indeed rods are almost absent from the fovea – the center of the retina – which we use for fine detail perception, basically the opposite of what was claimed), but instead happens because the signals from the three types of cone cells are processed into a single (monochromatic) lightness response, which we use for perception of fine detail. The signals from the cone cells are also processed into two color difference signals, but over bigger patches of retina: sort of a neurological analog to the "chroma subsampling" that happens in JPEG compression. In other words, JPEG compression does work because we see fine details monochromatically, but instead of "leveraging" this mostly irrelevant cone/rod difference as claimed, it's really using the same basic approach (averaging/tossing out color data) that the eye itself uses.

Actually, the next few sentences are somewhere between misleading and wrong, too.

> _"The eye is more sensitive to quantization levels of green light than to > levels of red or blue light, which is probably related to the fact that the > sun emits more power in the green region of the visible spectrum than in red > or blue. (The eye's spatial resolution in each of the three primary colors > is approximately uniform.)"_

The eye is more sensitive to green light because we use three cone receptors with the biggest overlap in sensitivity in the green part of the spectrum, so that when you add up their responses to a signal (in the combined lightness signal I mentioned), green wavelengths have more of an impact.

It certainly has something to do with evolution and the spectra of reflected sunlight, but various animals have different spectral sensitivities, so the causality is complex. The sun emits light over a huge range of wavelengths (far beyond the visible spectrum in both directions), and exactly which part makes it to our eyes depends on time of day, weather conditions, altitude, etc.

The three "primary" colors are somewhere between extremely simplified model, useful engineering approach, and myth. We also have somewhat different spatial sensitivities to the three primaries in a computer display, as far as I know.

> _"Also the blue and red subpixels are twice the size of green, making them > twice as likely to be illuminated at the perceptual edge of a hard intensity > transition than green."_

Let's see here. 1/3 the total area is green, 1/3 the total area is red, and 1/3 the total area is blue. How is it that edges are twice as likely to fall on red or blue than green, again? (In other words, there's some difference because of the different pixel sizes, but whatever is meant here is being poorly explained, and important assumptions about the edges in question are left unstated.)

Vision is complicated, and there's a lot of heavy math going on in the neurons in your retina, before signals ever get transmitted through the optic nerve. It depends on adaptation to current light level and color, on what size blobs you're looking at, on the surrounding colors, and on inferences about objects and how they're lit. These complexities lead to all those famous optical illusions. So it's worth using simplified models, to cut out complexity incidental to whatever you're trying to explain. But that doesn't give license to just make up stuff.

For anyone interested, this is a good place to start:

<http://www.handprint.com/HP/WCL/color1.html>

\</comment><comment>

One last thing. I'm pretty suspicious of this:

> _"Overall, it is hard to see any really good advantages to the PenTile > layout."_

Presumably the engineers who designed the thing had some compelling reasons. (It's conceivable that it was driven by a desire to make a worse display that could be better hyped by marketing, but that seems extremely unlikely to me; I'm suspicious.) I'd like to hear what those are instead of just a hand-wavey "I don't know what they are so I'm going to imply there are none".

<comment><USER4> "Presumably the engineers who designed the thing had some compelling reasons. (It's conceivable that it was driven by a desire to make a worse display that could be better hyped by marketing, but that seems extremely unlikely to me; I'm suspicious.) I'd like to hear what those are instead of just a hand-wavey "I don't know what they are so I'm going to imply there are none"."

Probably it has to do with manufacturing requirements. I think the author of the article erroneously assumes that the different colour sub-pixels should be more or less the same. For example, the article says:

"And the layout can't logically be argued to be a limitation in manufacturing capability, because it is clear that the screen manufacturing process is able to create full-resolution green subpixels that are one-third the size of a physical pixel."

This is actually true for LCDs because there the colour of a subpixel is defined merely by a filter that is put in front of the subpixel. However, this is not true for OLEDs. In OLEDS, each subpixel is a separate light emitting diode of the respective color. The light is not changed by the use of filters, but is generated only in a specific color to begin with. However, the light an LED generates depends on the chemical composition of the LED, so each different color LED is a physically different device.

In fact, if you remember some recent history, for most of the history of LEDs, there have been no blue ones (only green and red). Blue LEDs were a big relatively recent discovery. (This is why you only see blue and white LEDs in relatively recent devices).

So the manufacturing requirements for the different colors LEDs are different, and blue LEDs are the most difficult. So it is not at all surprising to learn that the manufacturing process allows for green LEDs to be twice as thin as the blue ones.

So the pentile layout was an attempt to minimize the pixel size given the above mentioned limitation of blue LEDs.

<comment><USER5> OLEDs also degrade over time. Blue is still the color with the shortest lifespan. Making blue larger will give an equivalent output for longer.

</comment></comment></comment><comment><USER6> Don't miss the rainbow picture on page 3, it's a pretty cool hack:

"I then developed a far more nefarious test of color fringing: an algorithm that would take an arbitrary full-color image and generate a pure grayscale stipple pattern that appears colored on the N1 screen. The interesting thing about these images is if you display them at anything other than 100% zoom, the colors disappear and you only see the grayscale stipple pattern."

</comment><comment><USER7> I have an iPod Touch and a Nexus One in front of me now. When looked at side by side, the Touch seems drab and fuzzy and the grid layout of the pixels stands out; while the N1 is crisp, and the white background of text is solid.

The thing it reminds me of most is a comparison between a CRT and an LCD. Apple seems to like applying more anti-aliasing to their fonts, certainly more than is customary on Windows, and it really shows on the Touch - <USER2> about the N1 having slightly fuzzy text when zoomed well out, the Touch's text is plainly fuzzy when zoomed to normal reading size.

Things other folks have brought up, like 18-bit with dithering vs 16-bit, I'm less concerned with. There's more contrast range in that 16 bits (by itself enough to make banding more obvious), while dithering doesn't strictly relate to the pixels displayed on screen and can be done in software. I expect updates can improve this.

The Cooliris Gallery browser the N1 ships with certainly does scale down photos before drawing them on screen; the browser is similar. This is annoying, especially if you want to zoom into a section on the photo, but again it's not related to the actual display. It looks more like an optimization designed to fit the image into a texture for hardware acceleration. Other photo gallery apps don't necessarily have the same implementation (e.g. B&B Gallery).

One actual aspect of the OLED display that does bother me somewhat is the way it "fizzes". When using the screen in the dark with the brightness at the lowest setting, all lit areas of the screen can be seen to be constantly flickering and alternating between different brightness levels at very high speed, a bit like the way the head of a freshly poured Coke's froth is constantly dissipating and getting renewed. But this is a very minor quibble.

As to contrast ratio with bright ambient light, I haven't found it to be a practical problem. I don't use my phone much outside during the day - even if I'm using the map, I'm more likely to be doing that in an evening - but even then, it seldom gets sunny enough in the UK to make the screen hard to read when it's at full brightness.

<comment><USER3> As has been discussed to death, the main thing is that Apple's font rendering doesn't go as far to align parts of characters to pixel boundaries. The result is that people used to reading text on Windows (etc.) will think Mac text looks fuzzy, while Mac users will think text on a Windows machine (or Android, presumably) looks unevenly spaced and sometimes wrongly shaped. It's somewhat a matter of personal preference. I'm kinda hoping we can all use 250 DPI screens and stop worrying about it at some point.

<comment><USER8> The Nexus One (and Droid) are high enough resolution that I wonder if they benefit from any subpixel tricks. I definitely don't see any major kerning problems on my Nexus One.

With hinting on (including the patented/smart auto-hinting) in X (not OS X!) spacing issues are pretty obvious, but it at least keeps fonts reasonably crisp on my normal desktop LCDs, which have a much lower DPI than Nexus One/Droid (and iPhone/iPad too)

</comment></comment></comment><comment><USER9> One thing that I couldn't find mentioned is exactly what the pixel addressability is on the display. In figure 2, the layout of the first two rows is (using RR and BB for the double-wide subpixels):

       RR G BB G RR G BB G RR G BB G RR G BB G RR G BB G
       BB G RR G BB G RR G BB G RR G BB G RR G BB G RR G

Is the upper left pixel in this (RR G BB), which the article seems to assert, or (RR G BB G) ? If I set the screen to entirely black and turn on pixel (0,0), which subpixels will light up (I don't find Figure 1 shows this well enough)? If (0,0) lights up (RR G BB), then the second pixel at (1,0) is (BB G RR) and overlaps the first? If it doesn't overlap, then the second G from the left in the first row is not part of any pixel. If one pixel is composed of two green half-sized subpixels and one each of red and blue full-sized subpixels, then the ratio of screen area to colored subpixels actually is the same for all pixels, it's just that the green subpixel is spread out more and the order of the subpixels is different in each row -- the later would undermine traditional, plain subpixel smoothing that assume a consistent, regular layout on all rows.

Notice that if you count subpixel groupings in figure 2, it's exactly 5 pixels across if you use (xx G yy G) subpixel layout (where xx and yy are either RR or BB depending on which row the pixel is on).

I find this paragraph confusing considering the layout given:

 _You can see from the photo above that each logical pixel on the Nexus One screen contains one green subpixel and either one double-width blue subpixel or one double-width red subpixel. So the red and blue color channels on the Nexus One display each have half as many subpixels (480_ 800/2) as the green channel. Basically, half the red and half the blue spatial information in the 2D image being sent to the display is simply thrown away or spread to the nearest matching subpixel by a convolution or intensity-dispersion process.*

And if (xx G yy G) defines one pixel, then this paragraph's math is just plain wrong:

 _One way to count raw pixels, ignoring the effect of all the signal processing on the PenTile display, is to calculate total effective RGB triplets on the screen. You can do this by taking a weighted sum of total number of red, blue and green subpixels, and then converting back to an effective screen size. The total number of effective physical pixels, counted using a weighted sum, is (480_ 800/2) _2/3 + (480_ 800) _1/3 = 256,000, exactly two thirds the claimed total number of pixels (480_ 800=384,000). This is equivalent to a screen with edge dimensions sqrt(256/384)=82% of the claimed length, or (480 _82%)_ (800 _82%) = 392_ 653 = 256k.*

... as the ratio of the _areas_ of each of the subpixels is the same, at least in figure 2.

If green has more prominence in the way the human eye picks up color, then it actually makes sense to spread out the green over separate areas (or different shaped areas) to give greater prominence to the harder to pick up colors of red and blue, which are more concentrated and thus brighter/richer. It seems from figure 1, the subpixel smoothing takes into account that the red and blue subpixels are ordered differently. It's also possible that the subpixel smoothing recognizes that the alternating ordering of red and blue can be exploited along the vertical axis to achieve the following layout (this is two pixels side by side):

       RR G BB G
       BB G RR G

which is also the same total subpixel area per pixel, but the whole pixels are more square (1.5 subpixels wide by 2 pixels high vs 3 subpixels (6 half-sizes) wide by 1 pixel high).

I personally don't see "waviness" in the lines on the screen, but I do see some stippling at the screen edges (easiest to see on an almost fully white lit screen, like the background (not the white border) of the HN content area). This would seem to be caused by the ordering change of R and B subpixels, not of the half-wide G subpixels.

<comment><USER10> > Is the upper left pixel in this (RR G BB), which the article seems to > assert, or (RR G BB G) ?

Take a look at the photo vs. the debugger snapshot of the "3G" text. The uprights in the G are 3 pixels wide, and display as one of either:

BB G RR G BB G RR G BB G RR G

Thus the point of the article: A "pixel" is either "BB G" or "RR G". There are 800x480 of these. But neither of them is "a pixel" (RBG) like we're used to talking about, it's less than that. There's one (small) green and one (bigger) red OR blue in each pixel.

I had a Nokia N810, with an 800x480 LCD of approximately this size. It was gorgeous. I was expecting something similar, but got this, with my N1. The screen is, easily, the most disappointing part of the N1 in my opinion. The enhanced contrast of the AMOLED doesn't come close to making up for the jagginess of the uneven pixels. Vertical, and especially diagonal, lines just look horrible.

</comment></comment><comment><USER11> There's been a few sites which brought this up..

On a totally unrelated note, anyone know if VOIP is working better on the nexus one's these days?</comment>


I've started wiretapping my kid because he hates photos (2017) - <AUTHOR> http://www.theverge.com/2017/3/3/14800098/recording-child-audio-phone-photos-parenting <comment><USER2> >I'll open up the voice memos app on my iPhone, hit record, and let it just sit there. It doesn't go entirely unnoticed; any notification or buzz will illuminate the homescreen to show white soundwaves under a red "recording" bar. But he's aware of what the phone is doing, and he doesn't seem to mind.

Uhhhh...this _does not_ seem healthy whatsoever.

<comment><USER3> It's interesting that you think that. I think many people would agree, and yet...

When we take a photo of somebody, we're instantly recording a number of decisions they made that day. In a certain sense a photo is a record both of the time the subject spent in grooming and selecting clothing and also every activity that individual has participated in since then which might muss hair or clothing.

By recording a person's image a photographer also records their recent diet and fitness level, their emotions, their posture and current action. It's a massive amount of data.

All these very personal things are recorded too fast for the subject to do anything about them. They're already dressed, already groomed, they already ate a donut every morning for the past five years. Some people hate photographs for this reason. It pins a person to the wall and forces them to see themself from outside.

By contrast, recording a voice -- assuming the subject is aware of the device -- puts the content of the memory completely in the hands of the subject.

From the moment a person knows that an audio record is being made only aspects of that person which will be fixed for posterity are sounds the person chooses to make. There is utter freedom in this. It even takes a significant amount of time for the recording to get anything usable.

One can hide from a microphone by remaining silent. There's no practical way to hide from a camera except to flee, and even then the photographer will have pictures of one running away.

Isn't it a little weird, then, that it's socially acceptable to take a picture of anybody you know at just about any time? Not undressed, of course, not in any intimate setting, but out in the world the most we're required to say is "aw, come on, smile, I'm taking a picture".

When was the last time you asked somebody close to you for permission to take a picture? How often have people asked you instead of taking out a camera and giving you instructions on posing?

Certainly, almost no parent thinks to ask a child if they mind the parent taking a picture or a video.

I kinda think this might be one of the healthiest ways to record your child's thoughts in times of developing identity.

</comment></comment><comment><USER4> This is creepy</comment>


Emulating a BBC Microcomputer in Javascript - <AUTHOR> http://xania.org/201405/jsbeeb-emulating-a-bbc-micro-in-javascript <comment><USER2> I remember going round a friends house and him loading up Elite onto a BBC B and my mind was blown.

An exceptional game in 32kb. Would be interesting to see if they get as far as running Elite.

<comment><AUTHOR> Elite is the default image! Head to [http://bbc.godbolt.org/](http://bbc.godbolt.org/) and hit shift-F12 to boot it :)

<comment><USER3> My MacBook Pro on Mavericks won't let me use Shift + F12 :(

<comment><USER4> You can change that. Goto Systems Preferences | Keyboard and then select the Shortcuts pane. Click Mission Control and then un-click the checkbox that binds F12 to Dashboard (which you probably do not use).

<comment><USER3> Thanks!

I do use dashboard (have my Selfoss RSS reader pinned to it) but only with my trackpad swipe-left :)

</comment></comment></comment></comment></comment><comment><USER5> Being an American, I was never exposed to the BBC machines. I tried running the emulator and entering a small program; alas, I can't figure out how to enter the "=" key, so I had to give up. I couldn't find "+" either.

I found the hardest part of writing my own microcomputer emulator in javascript was keyboard mapping. Each browser does things in a somewhat different way, and then there is the inherent tradeoff between emulating the original keyboard layout faithfully vs using a logical layout (where pressing "=" on the PC keyboard results in a "=" event in the emulator).

As for the CPU emulation speed, indeed chrome doesn't optimize switch statements greater than 128 entries. I got around this by coding it as "if (opcode < 0x80) switch (opcode) { first 128 cases } else switch (opcode) { other 128 cases }

I had tried using a 256-way opcode dispatch table, which was great for chrome, but it hurt firefox performance (which is blazing with the 256-way switch). Having two 128-way switches was pretty good for both browsers.

<comment><AUTHOR> Thanks!! I haven't really looked deeply into Firefox performance but I'll definitely give the two-way switch statement a go: thanks!

</comment></comment><comment><USER6> I'd love to see a messaging system set up to treat any of these JS Beebs currently running in any browser worldwide as though they're all on a single Econet.

</comment><comment><USER7> Great stuff. I used a BBC Master up until 1999 as a serial terminal for a Sun machine. The thing was an electronics and experimenters dream: well documented, built in decent BASIC and assembler and ports galore plus if you blew it up, £5 was about all it cost to fix it (I.e. just get another one off eBay). Think they go for a lot more than that now.

</comment><comment><USER8> This is really interesting to me. I actually started writing my own about three years ago, also called 'jsbeeb', in CoffeeScript. I didn't get around to finishing it, but the 6502 emulation worked, and it has just enough peripheral support to boot through enough of the OS to display the familiar banner: [http://i.imgur.com/HjxV3ks.png](http://i.imgur.com/HjxV3ks.png)

</comment><comment><USER9> Here is an x86 emulator in Javascript running Linux 2.6.20 for those who might have missed it (2011): [http://bellard.org/jslinux/](http://bellard.org/jslinux/)

From the awesome Fabrice Bellard (qemu etc...)

Edit: Formatting, additional details

</comment><comment><USER10> > Chrome's v8 at least bails out its JIT process if a function is either too > big, or if it has too many entries in the switch statement.

Is this true? Anyone have some sense of why?

<comment><USER11> I remember seeing in documentation somewhere that switch statements with more than 128 cases are not optimised in V8, that _might_ be what OP is referring to; however, I've never seen a 128-case switch statement in production, nor have I seen a developer use that many cases in development, refactoring tends to happen earlier in my experience.

<comment><USER12> > switch statements with more than 128 cases are not optimised in V8

I recently saw this in Petka Antonov's "Optimization Killers"[1], though I've definitely seen it somewhere else as well, because I recall hearing that variables mixed with literals in a switch could trip up the optimizer.

[1] [https://github.com/petkaantonov/bluebird/wiki/Optimization-k...](https://github.com/petkaantonov/bluebird/wiki/Optimization- killers#4-switch-case)

</comment></comment></comment><comment><USER13> Good read, although I now have a serious case of neck ache.

[http://i.imgur.com/HaVWV4H.png](http://i.imgur.com/HaVWV4H.png)

</comment><comment><USER14> If you type in:

        *CAT

at the prompt it will show an image listing.

        *Elite3

will run the game. Star is mapped to ' normally. It's quite sad that I typed the above commands correctly without thinking when I loaded the page :)

<comment><USER15> I can't manage to type the star. FF29, Win, German keyboard.</comment></comment>


Put Dates on Articles - <AUTHOR> http://mattmcgarvey.com/put-dates-on-articles

<comment><USER2> Put publication dates on articles.

Put publication dates at the top of articles.

Put publication dates in an unambiguous format (that means spelling out the month, avoiding dd-mm-yy, mm-dd-yy and even yyyy-mm-dd) at the top of articles.

Beyond that, it would be nice if there was a design convention that made older pages look different. I don't mean "you can tell this page was made in 1996, it has a flashing 'under construction' icon", I mean something more subtle.

Perhaps making older pages greyer? Wouldn't work with photos or videos though.

Perhaps making just the branding/navigation greyer? But as well as "old", grey also means "disabled".

<comment><USER3> If you're going to bother putting date on your page, put it at the top, close to the title. Always at the top. Thanks.

</comment></comment><comment><USER4> ... says the post with no visible date?

<comment><USER5> ...it says n hours ago at the bottom right.

<comment><USER4> My browser disagrees: <http://imgur.com/M2EoJ>

<comment><USER6> Disabled JavaScript?</comment></comment></comment></comment>


Amazon launches Start-up Challenge - <AUTHOR> http://www.startupsmart.com.au/finance/2011-08-02/amazon-launches-start-up-challenge.html

<comment><USER2> I have applied a couple of times. I don't have anything against Amazon and use their services every single day (my current startup uses it) but I'm hesitant to apply again.

Each year the "startup" that ends winning the competition has received a couple million in VC before entering or is a pretty well established startup.

Maybe I'm confused about what a Startup means these days (like mine for example: single founder, couple of collaborators, hustling every single day, counting pennies, you know the drill...) but 100K in cash and the Amazon Credits will be exponentially more helpful to companies like mine than to heavily VC invested "startups".

Either way good luck to everyone ;)

</comment><comment><USER3> Amazon link: <http://aws.amazon.com/startupchallenge/>

Entry period ends on Oct 2.

<comment><USER4> Thanks for the link.

There is no "save" button on the younoodle registration form: do you happen to know if the form can be submitted several times or just once?

(The form says _"Please only click Submit once"_ but is this just to avoid double "first submissions" or does it actually mean the form can never be re- submitted for the same applicant?)

Link to the form (EMEA):

[https://e.younoodle.com/c/aws_2011/er/aws_emea/submit?lang=a...](https://e.younoodle.com/c/aws_2011/er/aws_emea/submit?lang=aws- en)

<comment><USER5> @bambax – once you click submit on the form, you will always be able to return and edit your application. That message about only clicking once is there to avoid copies of the same entries. You are also welcome to submit more than one application, especially if you have different startups/business plans you'd like to enter. Please refer to our official contest rules for full details: <http://aws.amazon.com/startupchallenge/rules/> and drop us a note if you have any questions: awsstartups AT amazon.com (Disclaimer – I work for AWS)

</comment></comment></comment><comment><USER6> I'm not sure if they're offering it this year, but previous years' entries would automatically get $25 in free AWS credit. That alone made it worth to enter.

Don't kid yourself that you have a chance to win, but spend 10 minutes filling out the app to save $25. Not a bad deal.

<comment><USER7> They are; from the rules [1]

6\. ENTRY CREDITS. All eligible entrants who submit a qualified Entry will receive a credit of $25 USD (approximately 17 EUR) to be used toward Paid Services from AWS (does not include Amazon FPS). Individual credit codes valued at $25 USD (approximately 17 EUR) will be emailed to such entrants following the announcement of the Grand Prize winner.

[1] <http://aws.amazon.com/startupchallenge/rules/>

edit: formatting</comment></comment>


Productivity Tips for Programmers with ADHD - <AUTHOR> http://adhdtechies.com/productivity-for-adhd-programmers/ <comment><AUTHOR> I know there are a lot of ADHD programmers out there. These techniques have worked well for me.

I'd love to know what your challenges / solutions are as well.</comment>