A thought on the political, rather than technical, side of the story:
I went through a regrettable phase of reading about military strategy and the like, and one of the things that stuck was how good strategies need to have a component of randomness to them, to make them unpredictable by the enemy. Trump is chaos and randomness, and him having landed on this issue, and in such a random (?) and (apparently?) sexist way is both testament to that, and an indicator of the danger he poses to Democrats and what passes for the left in the US: They've left themselves exposed on many fronts because they've faced a very ordered and predictable foe until Trump. Nobody, but nobody, on the right would have launched an attack on the left with "women have told me dishwashers suck, now," before Trump, so they were free to pass stricter and stricter regulations, unpunished by the cost to consumer satisfaction.
I am loath to admit it, but there is something to be admired, here, some kind of low genius that demands respect, under threat of great peril if respect is not afforded.
> Pinker also talks about the "Euphemism Treadmill", where words that were specific medical terms turned into general insults and became unusable because of it ("spastic" in my lifetime has gone from a medical description, to a playground insult, to being effectively unusable, a non-word).
The choice of the example "spastic" is interesting for two reasons. First, it seems to be an exception among the trajectories of a constellation of related medical terms. Second, because it shines a light on some of the better ways that we've actually come to use these terms (as opposed to how their usage is conventionally perceived by those in a fever about PC run amok).
To take the first point, consider the originally medical terms "idiot," "moron," "imbecile," and so on. These were formerly used to describe degrees of mental disability in a medical context. I don't know for sure if the normative overtones were present in their original usage (Overtones that say, for example, "The person so labeled is sad, and/or unfit, and/or undesirable."), but I would be surprised if these terms were really as purely medical and otherwise neutral as terms like, for example, "Parkinsonian syndrome," "tremor," or "fracture," & etc. Their trajectories seem to have ended, for what seem to be contingent historical reasons, in their medical disuse and rhetorical popularity. "Trump is an imbecile," "Jim Jordan is an idiot," and so on. These bits of invective have entirely lost their medical denotative senses and function almost entirely rhetorically and connotatively, to wide acceptance. IOW, from medical description, to insult with continued medical usage, to being effectively ubiquitous as insults with not medical denotative sense. Interestingly, and contrary to the OP's assertion of the state of usage, "spastic" absolutely continues in medical usage. It refers to conditions that cause spasms, or to conditions and organs that are affected by spasms; the term "spastic colon" should put one's mind at ease on this point, if less at ease in certain other aspects.
In exploring this first point, and in considering the related terms "retard" and "retarded" that have gone through trajectories that have gone on to wide opprobrium, I'm not so sure we can really condemn this as PC run amok. This leads to my second point. It probably was very difficult for people with those constellations of conditions labeled as "retarded," people who were reduced to their diagnosis by being called "retards," to move about in a world where those terms carried the explicit weight of being used to insult people's worth and intelligence. "You are retarded. Shut up and feel your unworthiness, preferably away from me, because you are unpleasant," is really what is being said. "Not you, [or your relative]. They're one of the good ones [or they're not so bad]," probably did little to salve those wounds. In this regard, I feel that the trajectory of usage from medical term to vulgar insult to effectively unusable word results not from PC run amok, wrecking the language before we have a chance to cope, but rather from compassion and kindness working all too slowly against needless cruelty and defensiveness of long habit within the public consciousness to a genuinely better state of affairs, with the minor cost that some people get too wound up about protesting those words, and others getting too wound up about having the height of their robust expressive powers snatched away by the zephyrs of fashion.
> I'm all in support of reclaiming words. If we use "supremacy" for lots of other things, then its association with racists fades. Giving them sole use of such a useful word seems to be letting the bad people win, somehow.
I'm not sure that this is precisely how reclamation usually works. Reclamation is, historically, work undertaken at some cost by an oppressed group to take some the venom out of a term used to oppress them. Two prominent examples come immediately to mind: "nigger" and "queer." In the first case, reclamation of the n-word by black people in America entails not only at least tacit approval of its use within black communities and among black people, but a near prohibition of its use among white people--meant to insure that care and thought are used before engaging with the term--due to its history as a tool of oppression, and its continued present-day use as a term of oppression. "Queer," among non-cis persons, has had a trajectory that has landed similarly, but with much less strict of a prohibition against its use within the dominant in-group. (I suspect the difference has to do with the prospects the two communities have of "passing" within the larger culture; everybody knows you're black, and we don't need to look too long in the news to find heartbreaking examples of discrimination, the tip of that iceberg, only, being revealed to us in lawsuits against banks, workplaces, and the like. Gay people can at least pass, and are therefore perceived otherwise as diverse as, or not as diverse as, the general population. More, therefore, is too be gained from a conciliatory, even welcoming, set of rules around the reclaimed word.)
The contrast with "we" reclaiming "supremacy" should be clear. Numerically, to the extent that HN is US-centric, and more so to the extent that HN is tech heavy, "we" are white. Here, "supremacy," in its denotative sense, is about a normative schema that holds "us" as being deserving of the top position socially and economically. How much "work" are we going to have to do to "reclaim" this word? And to what end? We're just going to use it, from behind our keyboards, so that...other stupid people on the Internet know that we're the boss of us? It seems hardly worth getting in an uproar over.
What is worth talking about, without perhaps descending into an uproar, is this conventionally simplistic idea that "they are taking all our words from us because they are white knights compensating for their guilt or frailty." That idea, I hope is apparent now, largely functions reflexively to try to undo the real language work that has been done by minorities, the disabled, and their advocates to build a slightly less demeaning and fairer world (for us all, ultimately). If it means I have to say "Quantum Spiffiness" instead of "Quantum Supremacy" (HINT: It doesn't.), then I'm all for that kind of PC thought control run amok. The cost is clearly worth it, because I can get a job, and a home loan, and can walk down the street without suspicion of being a criminal, and everyone should have that opportunity; if I could remedy all those injustices by simply leaving a few words out of my vocabulary for the rest of my life, or if I could even help make the world a slightly better place by just being cautious and thoughtful with my usage, then sign me up.
> "In contrast to cargo-only chemical space-gun concepts, a mass driver could be any length, affordable, and with relatively smooth acceleration throughout, optionally even lengthy enough to reach target velocity without excessive g forces for passengers."
Wikipedia can generally be pretty good, but the above text from the subsection On Earth shows what can go wrong when deluded space enthusiasts go nuts on an article; it's pure wishful thinking. No major construction project of "any length" is "affordable," especially not one of the sophistication of a mass driver. At about 3g, about 30 m/s^2, it would take you about 270 seconds to get to 8 km/second, during which time you are traveling at an average speed of 4 km/second. This is a structure, with attendant control system and safeguards, about 1080 km, or 670 mi, in length. This is not affordable. By anyone.
What might be affordable (sticking my wet finger in the breeze) is getting 1 or 2 km/s at 5 or 6 g, or higher, and then doing the rest with a rocket, provided that you're firing continuously to amortize your initial cost. Skimming a couple km/s off the high end of the rocket equation brings your mass ratio way down, especially considering the reduced gravitational losses. (I'm assuming, in a fit of witless optimism, that we're launching from a high enough altitude that the increased aerodynamic losses are mitigated to the point that gravitational loss savings dominate, and that this adds no cost.)
Mass drivers are a fun idea because they seem to get around the rocket equation, but this affordability nonsense is just over the top.
> They have to stick that in along with the ole racist European trope.
Ostensibly, by "that," you are referring to the spiritual aspects of navigation noted in the article. But the "ole racist European trope" may better be classified as a plain acknowledgement of the facts on the ground. For example, the article states:
"To show that Polynesians descended from Europeans, Abraham Fornander in Hawai‘i, and Edward Tregear and J. Macmillan Brown in New Zealand, built the case at the end of the 19th century using the emerging science of linguistics to trace Polynesian languages back to Sanskrit and to European languages."
and:
"Ethnologist S. Percy Smith was one of several scholars who praised the Polynesians’ “intelligence, their charming personalities, and—one likes to think—their common source with ourselves from the Caucasian branch of humanity."
We could probably look up Fornander, Tregear, and Brown in the literature and gauge their relevance in their field. Ditto for Percy. Maybe it really is a liberal conspiracy to undermine the meritocracy. From the 1930s. Before we do that, though, maybe we should do a search on that tool of the left wing, Google, which turns up https://teara.govt.nz/en/ideas-of-maori-origins/page-2 among the top results for "aryan polynesian theory."
I think the quotes above more lend support to the idea that the article mentions in passing an accounting of the history of the (at least) sometimes racist scholarship in this area, rather than a trope. It's certainly possible that there are "factual tropes," I suppose. Nazis were, after all, pretty bad, no matter how many times we say it. (I have to say that I do think it's cowardly of people to hide behind the connotation of "fiction" in the word "trope." Like, they can't say "lie" or "propaganda" without revealing their racism, so they use "trope." Cheap.) However, calling something a "trope" in order to dismiss it as, I dunno, SJW tears or whatever, is a bit disingenuous. One might even call this common tactic an actual "trope," and a counterfactual one, of the alt-right.
Another version of this course (I think it was an OCW version on YouTube.) had a video of a fish holding position in a stream. There was an obstacle in the stream, and the fish swam up into its wake to save energy. Neat. Then they showed a video of a dead fish being towed through a simulated stream by a line. It exhibited "swimming" behavior that could be dismissed as just flapping in the current right up until the dead fish swam up into the lee of the nearby obstacle for shelter.
It's amazing how much adaptation and complex behavior can be embedded into an underactuated system. A fish's dead body "knows" how to save energy when swimming against a current!
> The Wright brothers are a timeless example of how private enthusiastic entrepreneurs can outperform heavily financed and government backed organizations. They’re also a prime example that a degree or title in itself doesn’t qualify you for success in an endeavor. Experience, imagination, and courage will generally be the currency that pays for success.
You sort of knew that bit was coming, but you can't really be prepared for that much hogwash that quickly.
First, they're obviously not a timeless example. A distinguishing feature of their time, compared to ours, is that there were no qualified aerospace engineers. Another feature is that the scientific and analytic culture was far more disjointed, immature, and parochial at the time. Consider, for example, fusion research today. No amateur will produce a burning plasma. ITER will. Because the scientific environment is more sophisticated, and is able to take on challenges outside of what amateurs can.
Second, they are not a prime example about the efficacy of a degree regarding "success," not least because n=1 in an endeavor riddled with variation. It's equally likely that they got very, very lucky, in spite of their apparent rigor.
Third, and finally, "[e]xperience, imagination, and courage" are not dichotomous with a "degree or title." It's not really apparent to me that, outside of the imaginations of sophomoric libertarians, that anyone believes that the world is stuffily dismissing outsiders who clearly have the facts on their sides in scientific and technical endeavors. Focusing on this fair-tale split between imagined elitists in their ivory towers and the pragmatic and gritty masses betrays a fascination with a staple of corny Americana, the garage workshop and its ilk. It's trite, predictable schlock.
> The well-known 10,000-hour principle, popularized by Malcolm Gladwell, illustrates an important lesson for developers. ...
It’s not often I’ll wholesale dismiss an article on HN because of one sentence, but this is one of those times. The fabulist Gladwell is not credible in general, and his 10,000 hour “rule” can no longer be thought to even remotely approach science, or even fact. The author lost all credibility with this sentence.
There's another way to frame that: What if it's a coincidence that the rent of labor has afforded a tolerable lifestyle for the masses and lavish lifestyles for capital owners for nearly 200 years? And, what if this coincidence that has supported a social order (explicit or de facto capitalism) is coming to an end?
I'm fond of Zizek's remark that it is easier to imagine the end of the world than the end of capitalism. It seems apposite, here.
I don't think it's particularly "naive" to believe that retailers or advertising companies could make enough off of a contest promotion to justify the cost of a car. Most of the cost models of contests are opaque and, in most of North America at least, there is probably a general perception that regulations would be in place for something that so prominently implies that it is a contest for a car. The "trick" here is to set up the appearance of a contest while evading the legal controls for an actual contest. The very trick of disambiguating this in the more-or-less fine print is probably only allowed in things that aren't sweepstakes or contests.
Yes, in hindsight, it may seem that only "naive" people could believe this, and that "rational" people see through it. But this strategy probably represents something like the endpoint of a search strategy that found a successful meme, precisely because it mimics authentic, regulated contests.
Measuring it would mean first figuring out what was valuable in HN and then tracking that. It may turn out that what was valuable isn't easily measurable, even with ML.
In a preliminary way, however, it seemed there used to be a stronger correlation between length of comment (as a proxy for thoughtfulness, perhaps crossed with reading level) and comment score. It also seemed there were fewer of the "I know nothing about field X, but let me pontificate on X" comments. Frequency of one-liners has probably increased, in relative terms. We could probably also look at the relative frequency of comments of the type "Thank you for your (specialist) explanation" or "Very interesting!" over time, as a more or less direct proxy for quality.
One might also be able to come up with a measure of "feeling of safety." In other words, the crowd probably perceives the level of discourse and guards their contributions accordingly. For example, "How do you measure the decline?," is interpretable as a technical question, or as a rhetorical question with "one" replacing "you," or as a snarky attack (by reading it with a sneering emphasis on "you," to indicate skepticism that a decline has happened), and so on. The general tone of replies might serve as an indicator, especially if crossed with something like days-since-joined-HN or karma.
But, really, my original comment was meant to contribute something positive while calling out, en passant, a particularly egregious kind of comment behavior that I am saddened to see on HN, particularly since I perceive a general decline over time.
Full(ish) disclosure: I burned down a previous account because I had made a shameful anti-Muslim comment a la Sam Harris, whom I'd been reading (and was inexplicably taken with) at the time. I could no longer edit or remove the comment by the time I'd come to my senses, so opted to irreversibly change the password on that account to gibberish. This is all just to point out that, despite my apparent HN youth, I can indeed seem to remember a time when thoughtful comments that represented either expertise or care elicited far more upvotes than they do now, and a time when short quips and adolescent snark elicited far swifter and more brutal karmic beat-downs.
I know that, for fixed winglets, there are a couple of (equivalent) ways of looking at them. The first way to look at them is that they resist the tendency of higher pressure air under the wing to leak around the wing tip to the lower pressure air on the top. The second way to look at them is that the winglets are flying in a circulating flow, and a portion of their lift is in the direction of travel of the airplane. (That one is trickier to see, for some.)
My educated guess is that tip propellers would operate counter to the vortex direction, so that their vorticity would tend to cancel the trailing vortices. Notionally, you could think of them as throwing air back under the wing, though that's just a heuristic I made up to help imagine the direction they'd spin.
> "the poor are trading years in the future for pleasantness now"
> This also describes how a lot of people are poor.
I suppose we should be cheered by your qualification "a lot of," since it seems to indicate that you at least have to acknowledge your growing awareness that some, if not the majority nor vast majority, of the poor are there for structural reasons, rather than shortsightedness.
What of those who are there for reasons other than shortsightedness? What of those for whom shortsightedness is a result of mental health issues? What of those who can see ahead, but see no bright future and are making rational choices in the face of that?
Fortunately, having qualified your remarks in the way you have, you have opened yourself up to a responsibility to think critically about those whom you have dismissed. I wish you the best in that.
The first thing I feel I need to point out is that my horse in this race is not whether or not jobs will go away, but whether or not the original commenter to whom I was replying advanced the discussion at all with their remark. I think that the remark–that people have always been saying that automation will take over but it never has–is facile in that the thing that "people have been saying" is not the same over time. In the late 18th century, it could only really have been a comment about capital concentration and the death of the trades. In the 1950s, it was very probably a naive comment about the power of as-then-understood computer technology's capability to replace manual labor or work. In the 1990s, it was very probably a naive comment about the state of the art of AI at the time.
Now, the remark is about actual inexpensive robotics in the context of what seems to be a genuine AI and computer vision and control renaissance, funded by government and corporations. Those are all just different remarks. To package them all up as one "thing that people have been saying" does a real disservice to the discussion. And it's a pose.
In the current case, I find it difficult to say whether the remark will turn out to be naive. However, any competent discussion of whether or not it is has to rely on an assessment of the current situation of computer vision, AI, control theory, economics, and law.
> People have said that it's only a matter of time...Yet it keeps not having happened just yet.
That's incredibly facile. Were there solid state digital electronics at the beginning of the Industrial Revolution? Was there machine learning? Motion control? Systems engineering? A robotics industry?
Just aping the "power source of the future" line from the fusion joke and pretending it's the trenchant result of long experience is the tactic of a 15-year-old.
I think I tell this story every time there's an article about the STS on here. When I was a precocious space cadet, I followed the development of the Shuttle as closely as a kid could before the Internet. I remember the initial promised launch cost of $50/lb into LEO. Young theothermkn weighed himself and worked out how much that would cost, and even tried to guess how much a capsule would weigh, and how much of a group capsule's weight that he would be responsible to pay for. Tough, but doable.
And then the price went to $100/lb. Okay, tougher, but still within reach. And then $500/lb. Ugh. And then $1,000/lb. Oh, well. Maybe a later version will be cheaper. Economies of scale! And then the newscasters stopped talking about the cost at all, except to note how far we were from the initial cost.
The Space Shuttle set spaceflight back 40 years. Years later, I got an aerospace engineering degree, and promptly left the field when I graduated because I didn't want to work inside soul-crushing aerospace institutions without even the hope of doing anything good.
We may never recover, given that all our eggs are in the SpaceX basket.
I get that the idea that we "went to the moon with a slide rule" and similar ideas are appealing, but I'm not convinced that your statements are resting on a basis of fact.
For one thing, I'm not convinced that your mental models of what a "mission computer" is and what a "mission computer" would be doing, or when, make sense from an engineering perspective. I'm also not convinced that you know what an orbital perturbation is, nor how they would be used to plan and fly a mission.
To take an example from aviation, we didn't have practical simulations of general viscous fluid flow in the 1960s, but it would be meaningless to say that we "used Bernoulli's principle" to fly across the Pacific.
The Apollo vehicles had an on-board IMU. A trajectory could thus be pre-planned and flown to using feedback control. That trajectory would certainly have been calculated ahead of time. Thus, while there would be no need to have "[done] the math involved dynamically," that by no means implies that patched conics were used while in flight, nor does it imply that they were in any meaningful way used for the final design of the missions' flight paths.
Further, on any deviation from the planned flight path, numerical integration methods would yield results that would be good enough for later correction, again, by using feedback control.
If you still need to believe that "KSP math" is how we got to the Moon, go ahead. You've certainly done nothing to convince anyone else, though.
> Yes we sent astronauts to the moon using KSP math.
I'm almost positive that we did not.
While patched conics would have been used very early on for rough mission analysis and design, we had a very good understanding of perturbation theory at the time. Wikipedia tells me that the restricted 3-body problem was also essentially solved in 1917. I've seen very detailed plots of the free return trajectories that the Apollo missions followed, too.
Using patched conics for the earth moon system would have resulted in an error on the scale of lunar escape velocity upon entering the sphere of influence of the Moon.