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Comment by Dalewyn | Hacker News Reader

This and the previous thread on this subject have highlighted some interesting(?) things, at least for me:

* The IT community, despite the majority being some form of an intellectual, has either a flawed (read: Hollywood) or no understanding of physics or military aviation.

* The IT community, despite the majority being some form of an intellectual, has a patently insufficient understanding of how sovereignty, diplomacy, and laws work.

* The Chinese apologists are hilarious to witness, particularly the ones who believe two wrongs make a right.

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First time? Basically any not-directly-IT domain gets talked about this way. Hell, even times where topics like Health and Nutrition come up you find a lot of wildly inaccurate statements being made here.

I think the problem is too many people see themselves as the type of generalist Intellectual when they shouldn't.

I completely agree. One fun thing about HN though, is that every once in a while an expert from an obscure domain drops in with an extraordinary comment. It is rare, but delightful when it happens.

“engineer's disease”

https://news.ycombinator.com/item?id=10812804

Ah, I used to call it the “school teacher’s disease”. People spend their whole days in environments where they are indisputable experts, then they carry their patronising attitude elsewhere.

    even times where topics like Health and Nutrition come up you find a lot of wildly inaccurate statements being made

On hackernews alt-med is repackaged as "biohacking" (sic!) and suddenly injecting yourself with home-made concoctions because you've read some research that some stuff had some effect in vivo or you came up with it yourself after reading wikipedia is lauded as next frontier of medicine or transhumanism come home.

I mean, that's every non-IT topic in an IT forum. It's to be expected from all forums really. Everyone has blind spots about other professions.

I think the key is to treat off-topic threads like watercooler talk, friends shooting the shit with each other and enjoy the drama.

I'm sorry but I gotta laugh at "despite the majority being some form of an intellectual", as if that is worth something. If you don't have the experience and the domain knowledge, can you call yourself an intellectual in that domain?

When I call myself an intellectual, it is mostly a form of pride or vanity.

As a boy, I read Ender's Game and Zhuge Liang's commentaries on The Art of War. As a man, I like to imagine that I now know enough to keep the whole world safe from catastrophic war. It is a comforting illusion.

> "despite the majority being some form of an intellectual", as if that is worth something.

I think I would phrase that as "despite the majority thinking of themselves some form of an intellectual, outside of their domain, they are out often out their depth and unaware of it".

> If you don't have the experience and the domain knowledge, can you call yourself an intellectual in that domain?

Yeah, that's the thing. You can assume that "in that domain" is irrelevant, and call yourself an intellectual, period. You can and you'd be wrong, very wrong, but you wouldn't be alone. It's common.

The thing is the IT community should know better. You know what goes in airplanes and missiles? Computers.

Not understanding how high 60,000 feet (roughly 18km) is is embarassing when you're an engineer of some description.

This phenomenon is something I've noticed with other subjects too; like a lot of the IT community not understanding how life works outside of cities when we talk about transport and infrastructure.

IT professionals affect the world in very significant ways with their engineering, but they also seem like some of the most naive/ignorant people I know of. I'm greatly interested in why this seems so.

> but they also seem like some of the most naive/ignorant people I know of. I'm greatly interested in why this seems so.

Combination of poor social skills and arrogance.

> but they also seem like some of the most naive/ignorant people I know of. I'm greatly interested in why this seems so.

It’s the arrogance associated with it. A kind of “I understand this complicated thing (computers) so everything else is trivial to me”. To learn something, you need the humility to say “I don’t understand”.

There is likely a selection bias at work here. Anyone who correctly identifies that they lack the domain knowledge to leave a well informed comment will not post. So most posts will naturally be by the uninformed or arrogant, but we have no idea what the ratio between these two groups is because people who dont post are impossible to count.

Dunning Kruger?

It's not uncommon to find people on HN who are "in the room" when top-level decisions are being made in healthcare, defense, finance, etc

That's different from when an Oncologist forum is discussing SEC actions or an Accounting forum is discussing laser-guided munitions... or at least it might be different: you rarely know on HN who is speaking from direct knowledge.

And if it's about defense or proprietary information then HNers with knowledge will lurk but not participate.

I work at NASA. We had a big review meeting for a space brayton (turbine engine) concept. One manager-level engineer absolutely thought that the spinning rotor would apply a constant torque to the spacecraft that would have to be constantly counteracted. I tried and failed to explain conservation of angular momentum to him.

I studied physics and it always surprises me how many good engineers really don’t have a very good intuitive understanding of basic physics principles like conservation laws.

I’m just checking my intuition here. An accelerating or decelerating rotor would apply an angular force (first derivative), while a constant rotation would not?

Yes. The time derivative of angular momentum is torque.

Great, sounds like our tax dollars are hard at work then.

I'm confused... you are right that it takes no additional torque to keep a frictionless rotor rotating at the same angular velocity, but in the real world there is friction and air resistance where you have to keep applying torque to keep something spinning at the same rate. and if you are applying torque to someone, then that thing is applying an equal and opposite torque back... is it not?

> if you are applying torque to someone, then that thing is applying an equal and opposite torque back

Yes, just like with a force.

> but in the real world there is friction and air resistance where you have to keep applying torque to keep something spinning at the same rate

Yes, but I think you are forgetting one thing: If the friction is between the rotor and the body, then this friction does not only act on the rotor, but also on the body. I.e. the friction creates a pair of torques which the engine can perfectly counteract with it's own pair of torques.

If the friction is between the rotor and the air, then yes, the spacecraft needs some kind of counteraction or it will start turning.

If rotor has 0 friction mounting then sure, no constant torque. Otherwise small constant torque that depends on friction.

See, in physics, you can assume there is no friction. Engineers often forget this one weird trick.

>"See, in physics, you can assume..."

In theoretical model of ideal XXX. Not when asked to actually calculate something practical unless the ideal model is good enough for constraints.

I am not an engineer. Actually MS in physics however ancient ;)

It's an old engineering jibe, of course :)

I suspect that the engineer in the GP's story might not remember the equations for angular acceleration, but has an intuitive sense that if a spinning something is in contact with a non-spinning something, you need a good reason for why some of the energy won't get transferred from the former to the latter.

Which is balanced by the torque applied by the working fluid that's being shoved through the rotor to keep it spinning.

Friction with the helicopter doesn't matter, friction with the air does.

Let me see if I got this: for instance, a helicopter can turn off their anti-torque tail rotor if the speed of the main rotor is constant?

No, because the main router isn’t applying a pure downward thrust. It’s also moving air in the direction of rotation. A turbine has internal baffles and the ducting itself to direct the air in one direction (?)

without friction with the air/medium it would have to turn it off or it would start spinning

Yes and no. The torque in helicopter is primarily a side effect of power being applied to the rotor. When a helicopter auto rotates (such as after an engine failure), the pilot has to remove anti torque forces with the pedals. This remains true even when you change pitch to slow your descent to the ground. So as long as no power is being applied, if you are in a free descent with a constant rotation on your rotor, then no, you will not need anti torque.

Source: I am a helicopter pilot.

Fantastic, thank you!

What about friction? Wouldn’t that cause torque?

The apologists do a good job of burying inconvenient info. I guess the fact that China is escalating the situation today is hard to justify.

Edit:

https://apnews.com/article/politics-united-states-government...

https://www.bloomberg.com/news/articles/2023-02-06/china-let...

China is publicly saber rattling? Must be a day that ends in Y.

You would think given the situation they'd say "no comment". It's incumbent on China given that they violated US airspace to not make the situation worse. They have to know that it is an impossible situation for the US to back down in. They're basically ensuring we get locked into an escalation cycle.

Edit: And by loosening their censorship on nationalist commentators to say incendiary things means neither side has any room to maneuver. It's like adding in dynamite.

Then why would we assume they want anything other than an escalation cycle? Didn't foreign orders fall by some massive amount over the past year? One narrative for why the Chinese people tolerate their totalitarian dictatorship is the economic growth and prosperity they believe that it has bought them.

This is not likely to remain constant given the above, and thus the tolerance of the totalitarian dictatorship is similarly unlikely to remain constant, and what does a dictator with a slipping grip on power want to shore it up? A nice foreign skirmish.

If this cycle gets momentum, with the war in Ukraine going on, there is no way to control where it goes. It's the ultimate gamble. I thought they would be more careful than to roll the iron dice.

If you're a one man dictator shop and you're guaranteed to lose unless you roll, I guess you roll. To hell with the collateral damage, if you cared about that you wouldn't be a dicator to begin with.

Nationalism is a hell of a drug.

I think because, to most external viewers, why China would want an escalation cycle makes no sense. It only harms China.

China wants a common enemy to distract their population from problems at home.

Beware, because this is basically the case on every non-software topic here. I come for the entertaining takes from smart people trying to get it right. They often don’t. The moment the scales fell from my eyes was at a former company where several engineers were talking about their essential oil remedies.

> despite the majority being some form of an intellectual

Wait what? What is your definition of intellectual because I don't think this is remotely true.

>* The IT community, despite the majority being some form of an intellectual

That's your first error. Any trade can encompass a swath of subjects and nuances from history to technology, niche technique and even underlying mathematics thousands of years old, including those that built the floor your chair is on right now, but you'd probably drive by a construction site thinking the mouth breathers are right where big brother market sorted their 'intellect' to.

Could you be more specific about the first part?

I think that why choose a missile over guns is a legitimate question.

As the author also later finds out, and only suggests it, perhaps using guns might have also worked, but just seems riskier because the proximity to the baloon (for the aircraft) and terminal velocity of bullets (though the baloon was shot down over safe airspace)?

There’s a direct parallel where a high altitude balloon survived thousand rounds. It just doesn’t shoot it down in a reasonable timeframe.

https://www.cbc.ca/amp/1.6737831

I don’t see how expertise at using the latest javascript framework to serve advertising makes you an intellectual. If I feel I have too much karma and need a few downvotes, all I need to do is post something correct about physics or mathematics that’s even slightly counterintuitive. It never fails.

> The IT community...

...is full of rather ignorant people who see themselves as "very smart" and therefore foolishly talk like they are an expert or near-expert in any area, especially after they've spent a half-hour reading Wikipedia or read some popular-audience book.

IMHO, it's generally the best policy to assume that an expert or conventional wisdom in another field is more correct than whatever "fatal flaw" you can think of in 30 seconds to form an internet comment. The main caveat to that is when political or ideological conflict is at play, no one should feel they need to defer to an expert's ideology or favored political policy choices.

> The IT community

Otherwise accurate, I can only object to your use of this phrase as intentionally vague when you could easily have been more specific and accurate: it is only software developers, apparently, that know everything. Network Engineers, DBAs, Systems Administrators, Tier II and Help Desk Technicians do not behave this way, but generally approach problems from a synthetic perspective of ignorance rather than knowing everything there is to know a priori. Developers are creators, gods among men.

This is simply humanity.

The subject does not matter, intelligence and other cognitive capacities do not matter, here there or wherever does not matter.

Almost no one ever works from the assumption that they are ignorant regarding a topic, and partially to wholly mistaken about everything to do with it, despite this being true.

Yup.

Took me spending hundreds of hours learning about AI risk to realise I know fuck all.

Oh no, people are asking "stupid" questions and speculating about things they are not experts on. How terrible - someone might learn something.

> insufficient understanding

Insufficient for what? We are on a discussion forum. It's not like people here will have perfect knowledge about IT topics either, not to mention that there could be multiple correct actions/decisions besides the one that the expers have chosen.

We should be encouraging more critical discussion, not shaming people for daring to ask questions.

Not only are people here ignorant outside of IT (and often inside of IT as well), but the average age of commenters is 15.

> The IT community, despite the majority being some form of an intellectual

No, the majority are some form of tradesman.

I haven’t been paying attention. What is the proof that it’s Chinese and not Russian or from Brazil?

The Chinese already have confirmed it was theirs, so there is that.

This behavior isn't unique to the IT community, as XKCD has observed with physicists: https://xkcd.com/793/

> * The Chinese apologists are hilarious to witness, particularly the ones who believe two wrongs make a right.

No need to be apologetic about a $1 trillion project shooting down a fricking balloon. At least the Soviets were sensible enough to let Mathias Rust land his airplane close to the Kremlin.

My head is spinning so fast from this comment, you could probably use me to chop down Chinese balloons out of the air.

No, you don't seem to understand. Having used the F-22 in "combat", the program is used up. Now we'll need to play another card to deal with another threat. The balloon was just to tank our defenses. That's why you always build small disposable defenses as well as expensive ones. Our radars were all tapped tracking a balloon! How can we withstand even a bomber run now?

> No, you don't seem to understand. Having used the F-22 in "combat", the program is used up.

The US could have strategically used that $1 trillion on its human resources, on things like school and healthcare for all, that way they wouldn't have had a 25% deficit in recruiting personnel (last I've checked). But, hey, building an airplane that can shoot down balloons for the same amount of money I guess also works.

Yeah, I know about the opportunity costs of dissuasion ("nobody is going to attack us if we've got a $1 trillion airplane"), but, again, in the great and long-term strategic scheme of things looks like that was the wrong choice for the US.

Ignoring the other problems with this post, where did you get the $1 trillion cost from?

Somewhere on the internet, Twitter I think, I now see that the official sources give lower figures. Also, most probably according to those figures the war in Afghanistan also didn't cost more than a few hundred million.

What "other problems"? I hate it when people do that, i.e. saying stuff like "you're generally wrong, but I won't say exactly what, because you're so very wrong". Just say what you specifically say you see as wrong or don't say it at all (to be clear, this is not directed particularly at you).