the reaction wheel works because of the large moment of inertia of the wheel. when the bike begins to tip over, it applies a torque to the wheel. you can imagine trying to get that wheel turning with your hands, it would offer a lot of resistance at first before getting up to speed. the bike is applying torque against that resistance and this moves the bike. this means that, if the moment of the wheel is large enough, and the correction small enough, you could make a correction without even spinning the wheel very much at all.
when the bike is making a correction, it can overshoot and then stop the wheel suddenly, which would ultimately result in the bike becoming perfectly upright and the wheel not accumulating any speed from one correction to the next.
if the momentum of the correction you need to make is greater than the momentum of the wheel spinning at max RPM, then the bike will fall over. this means that the system will fail if the bike is pushed too hard, becomes too off-balance or if there is something heavy, like a person, on top of it. with a wheel that was heavy enough, and a motor strong enough, the bike would be able to make itself upright from laying on the ground or keep itself upright with a person and cargo on top.
very frequent topic here on HN. i remember a comment about a persons experience with the public schools in the soviet union when it collapsed. all the smart people pulled their kids out and did something else. its the same as everything else because if you want it to be done right then you have to do it yourself. there is no fixing public schools... they are run by the majority and they always will be. the problem isnt the schools, its the majority. after WW2 all the dumbest people fucked like rabbits with no financial or existential limitations to stop them, medicine increasingly spared idiots from the consequences of their actions. this initial seed of stupidity brought the next tooth of the ratchet into place: the popularization and normalization of eliminating all consequences from ones own actions. we just keep getting dumber. we were supposed to be re-galvanized by a major depression and a pandemic in the past 20 years but we postponed it all with technology and massive economic manipulation. eventually the chickens are going to come home to roost... in the meantime dont let the public schools rot out the inside of your kids head.
What has happened to this site? We have a topic on the front page of the site for 15 hours now, with almost 400 comments, and the top comment is a nakedly eugenicist screed about "the dumbest people" having too many babies.
ive been here since 2014. i didnt bring up eugenics, but if you want to broach that topic then fine. intelligence, as well as all other traits or characteristics, of not just humans but all organisms, is subject to natural selection. if you deny this, you deny natural selection and this would make you a science denier. whether we should act on this fact, or the morality of doing so, is completely up to you. but you will not deny science on hackernews.
oh and you saw my comment at the top because the ranking algorithm takes the youthfulness of the comment into account. its rather embarrassing that you dont know this.
I went to a public school in a post-communist country in the second half of the 90s.
Back then private schools were generally regarded as lower quality because of the incentive to keep the parents happy with their "educational product".
i love the time that we live in. people talk about there being a glut of podcasts, but i can type "Peter Scholze" into youtube and there is a full hour-long interview with him hosted by another mathematician. you can see her channel is very new and almost certainly a part of this latest wave of pandemic podcasters. its so great to take an interest in a random person from a nature article and be able to immediately get a visceral idea of who he is and what hes about.
its strange how soviet union stuff is a fetish for coastal people but you never see much nazi stuff. the soviets murdered more people than the nazis and they are objectively evil. but that detail is simply lost somehow.
If a watch enthusiast owned and wore a 1938 Lange System Glashütte swept-second watch, I wouldn't think he was a fan of what the Nazis did either. I'd think he had a cool vintage timepiece.
yes, exactly. everyone is very quick to point out how evil the united states is. but there is no public reaction about the soviet union in which millions upon millions of people were deliberately murdered. more people than the nazis and the united states. i point out the absence of objectivity when i see it because i am a good citizen.
What if you separated the doings of the nations' leaders and military from what this is, a discussion about old school technology in the form of watches? One presumes the watchmakers didn't run gulags in their spare times.
Do you show up in discussions of 60's muscle cars and moan about the USA dropping nuclear bombs in Japan?
I was wondering what sort of "good citizen" has this username and spouts this... stuff, so I checked your profile. You wrote previously:
> my peers seemed super petty and intellectually average. easily pulled into dogmatic, fuzzy ideas.
>but there is no public reaction about the soviet union
There's literally non-stop public reaction against the Soviet Union, a country that stopped existing 30 years ago, especially in threads like this that are completely non-political. Case in point, you, congrats on being the first person who thinks watch connoisseurs are committing wronkthink by talking about watches.
You need a chrome/FF extension that adds to every comment an extra sentence like:
- "I disagree with Stalinist grain policies"
- "The Soviet Union murdered millions"
- "I think the Ukrainians are right to complain about the USSR"
- "They were too many gulags if you think about it"
- "But of the course, the Soviet Union was bad"
- "Stalin? No, I disavow him"
Then you don't have to derail a thread about watches to defend the Nazis and United States from the ghost of Stalin.
thats going to be one of the biggest shocks to society going forward when it comes to the changes that AI bring. there are mountains of data everywhere that is completely overlooked simply because the cost of processing the data is too high. too high to discover patterns/correlation and too high to process in any case.
human beings filter out most of what goes on around them. they dont see the world as it is and their minds dont keep track of physical primitives. their minds abstract the world into larger conceptual parts and track those parts. its not just a question of processing power, its a question of intuitive access. and nobody realizes this yet because the only sentient beings who are around to demonstrate any of this have those filters in place. when the AI comes with all that horse power and with no filters, it will see things all around that we are blind to. it will seem as though it can make impossible predictions. it will seem god-like, even before it graduates to doing something other than simply observing the world.
i was born and raised in california. i left a year ago for the midwest.
the situation in california is depressing. and im not talking about human poop or homeless people. im talking about jobs, culture and general lifestyle. california is filled with lots of very ugly urban wasteland. its filled with lots and lots of very disadvantaged people, hordes upon hordes of people who might not be homeless but are involved in crime and smoke meth and shoot up heroin. there is broken glass on every other sidewalk. its basically legal for people to steal things as long as its less than a thousand dollars, in that the penalty is so small that it might as well be legal. im just rattling off my lifes truth, my memories.
but worst of all is the grey dread everywhere. people in california do not think for themselves. they are so career oriented and so entangled in the bureaucratic system of formal societal infrastructure that basic common sense is dying a brutal death and you can feel this when you are amidst it. i always felt anxious because its a society resting completely on its laurels. there is nothing propelling it forward besides the momentum created by the previous generation of single minded, abrasive intellectual mavericks who raged against convention and dogma. now california is the embodiment of convention and dogma. its largest companies have transitioned over the past ten years from pioneers to custodians of entrenched power and market dominance.
i could feel this when i was a small boy growing up in the san francisco bay area. my peers seemed super petty and intellectually average. easily pulled into dogmatic, fuzzy ideas. most of them anyway. when i imagine the country now being the result of my generation growing up and using their dollars and tweets as their votes, it all lines up.
if you allow people to work from home you can pay them less because they will be able to cut their living expenses in half when they move out of LA/SF/NY. there are tons of great places to live all over the place. work-from-home would be a boon for the whole country and undo some of the damage that was done after the middle of the country lost all its manufacturing jobs.
there is no RANDOMIZED, controlled study that proves this kind of food is healthy. it isnt proven to be healthy. it likely isnt healthy. foods that are labeled "healthy" like orange juice and brown rice are likely very unhealthy and probably cause thousands of preventable deaths every year. if elon musk is not allowed to call his cars self driving, then people should not be allowed to peddle "healthy" food that isnt shown to be healthy.
when the bike is making a correction, it can overshoot and then stop the wheel suddenly, which would ultimately result in the bike becoming perfectly upright and the wheel not accumulating any speed from one correction to the next.
if the momentum of the correction you need to make is greater than the momentum of the wheel spinning at max RPM, then the bike will fall over. this means that the system will fail if the bike is pushed too hard, becomes too off-balance or if there is something heavy, like a person, on top of it. with a wheel that was heavy enough, and a motor strong enough, the bike would be able to make itself upright from laying on the ground or keep itself upright with a person and cargo on top.