HNHacker News
TopNewBestAskShowJobs

stopping

453 karma · joined November 19, 2019

submissionscomments
stopping··on I heat my home by mining crypto currencies
This is incorrect. We measure the "efficiency" of a heat pump by the amount of heat moved into a space divided by the work energy provided to the pump (electricity in this case). This is called the "coefficient of performance". Typical heat pumps have a CoP of 3 or more. Meaning, you can spend 100W of electricity to pump 300W of heat into your home. A purely resistive heater only has a CoP of 1.
stopping··on Activists who embrace nuclear power
>How about reduce that to 0 for night-time?

No, GP is averaging out across the whole day. If you get 100W during daylight and 0W during night, you can average to 50W for an entire 24-hour period. GP took 30W as a conservative estimate, which is entirely reasonable.

stopping··on The Buy Nothing Project
My local group encourages a 24-hour waiting period to equalize the opportunity for group members to claim items. Generally, the people who really need a certain item don't have enough free time to constantly check the group, or are working the sorts of jobs where they're offline for long periods of time.
stopping··on Stanford pulls plug on the return of freshmen and sophomores to campus
Well, let's use the CDC estimates for comparison:

  Estimated flu infections per season: ~25,000,000
  Confirmed COVID cases last 12 months: ~22,000,000
  Estimated COVID cases using 7x reporting ratio (CDC): ~154,000,000
If we compare CDC estimates for both diseases, COVID is 6 times more infectious than the flu. So, CFR doesn't tell the whole story, and it is disingenuous to pretend that it does. I think your original comment calculated an estimated CFR of 0.278% for COVID (253k deaths divided by 91M cases by end of November), while the estimated CFR for the flu is 0.16% (40k deaths divided by 25M cases per season). Using these numbers, the CFR of COVID is 1.7 times that of the flu. But, when multiplied by the infectiousness, it kills 10 times as many people. A comparison of the absolute death toll matches this result:

  Estimated flu deaths per season: ~40,000
  Confirmed COVID deaths last 12 months: 360,000
Note that the number of COVID deaths is under-representative because several months accounted for a period of low-spread, whereas flu is already endemic in the population. COVID was roughly considered widespread in April, so that's 9 months of full-on proliferation with 356,000 deaths. Extrapolating for the next three months projects ~475,000 deaths from April 2020 thru March 2021. This is probably an underestimate because if the next two months are like December (as projected), we'll hit just over 500,000 deaths. Now, we don't even know how many COVID deaths are unreported, but for the sake of argument we can just pretend that this is negligible.

So, even a modest estimate of projected deaths also confirms that COVID over 10 times deadlier than the flu in absolute terms.

stopping··on Stanford pulls plug on the return of freshmen and sophomores to campus
I have so many strong disagreements.

First, GP is nowhere near "half-right". Most egregious is calculating a CFR which is one fifth of the true value (as best we know with the current data). This is much closer to "absolutely wrong" than "verifiably correct", so no, "half-right" is absolutely a stretch in my book. In terms of absolute severity COVID is roughly 10 times deadlier than the flu, so there is no comparison here. And this is before we even begin to talk about the lasting effects of the disease. Suffice to say that there is no argument in terms of severity; COVID is much, much worse than the flu.

Second, comparing four months at the beginning of the pandemic when the disease was early in its spread vs. four months of endemic flu season (where the flu virus already has a sufficient foothold across a wide swath of the population) is completely erroneous. A much better comparison (though still imperfect) would be to measure across the same time period (December-March) with the same societal mitigations. In the last month, we've seen nearly 80,000 COVID fatalities in the US, so if we want to assume a similar rate over the next 3 months (likely an underestimate given the current upward trend), that's 320,000 deaths. And that's with fairly substantial behavioral restrictions to reduce the spread of the virus. You also neglected to mention that the 2017-2018 flu season was the worst in the last 10 years, where most flu seasons attribute around 40,000 deaths in the U.S. each year. So, even if we decide to ignore the fact that COVID cases are already suppressed due to behavioral mitigations, and me being generous with all of these estimates, at the very least it is four times worse than the worst flu season we've seen in the last 10 years. In reality, COVID unabetted is probably on the order of 10 flu seasons wrapped into one.

Come March we'll have a better estimate of flu deaths for this season, but I wouldn't be surprised if the restrictions see the number of flu fatalities drop below 20k or even 10k. Granting some intellectual honesty, the stats would unfortunately be significantly confounded due to COVID-induced strain on our healthcare system, and the fact that many individuals who would have died from the flu are now dead from COVID instead. But as a loose comparison, I foresee that ~20 times more people will die from COVID this winter than from the flu.

Like you said, policy is a different matter. Obviously it's worth discussing varying isolation strategies so that low-risk populations aren't significantly affected by the lockdown measures, while high-risk groups are isolated and supported. But that is a completely separate discussion. My main concern is with speech that abuses numbers and proliferates a societally-harmful mentality without discussing any of the actual nuances and trade-offs of the issue. As a suggestion for future commenters, if you want to try to compare the harm of lockdown measures versus the harm of the disease, you better make sure that your numbers are accurate before moving on to cost-benefit analysis.

stopping··on Stanford pulls plug on the return of freshmen and sophomores to campus
The CFR in the United States is 1.67%. Your numbers are wrong.
stopping··on Stanford pulls plug on the return of freshmen and sophomores to campus
Your numbers are wrong. There are 21 million COVID-19 cases in the U.S., and 350,000 deaths. That's a CFR of 1.67%. You picked the number of worldwide cases and compared it to the number of U.S. deaths.
stopping··on YouTube bans Steve Bannon's podcast channel
Even if corporations were to pre-emptively ban all speech that threatens to undermine the public faith in our elections, there is still a legal system which allows for complaints to be heard fairly. For all practical purposes, "How many people can you broadcast your message to" has effectively zero bearing on the strength of your legal case. Therefore, I don't see how banning seditious speech opens up an avenue for someone to actually steal an election.
stopping··on College campuses are designed at human-scale – cities can be too
I wonder if it's possible to make a fully-walkable city modelled after a college campus. Let's play with some numbers. I'll make some conservative estimates of space requirements.

  Indoor residential space: 400 square feet per occupant + 200 sf fudge factor
  Indoor retail space: 25 sf per-capita + 25 sf margin
  Indoor office/misc job space: 200 sf per office worker + 50 sf margin
  Indoor schooling/daycare: 150 sf per student + 50 sf margin
  Indoor supporting infrastructure: 20 sf per capita
  > Hospital requirement is only around 1 sf, so I'm just adding an arbitrary margin to account for rarely-visited indoor locations (e.g. churches, community centers), storage for city vehicles (fire department), waste management, etc.
Rough population proportions by age group in U.S.:

  0-18: 24% ("student age")
  19-64: 63% ("working age")
  >65: 13% ("retirement age")
Let's take all of the worst-case numbers, that every working-age person requires office space. The total space requirement for a population of 1000 individuals is:

  Residential + Retail + Office + School + Infra
  [600 * 1000] + [50 * 1000] + [250 * (1000 * 0.63)] + [200 * (1000 * 0.24)] + [20 * 1000]
  600k (Residential) + 50k (Retail) + 157.5k (Office) + 48k (School) + 20k (Infra)
  875.5k square feet per thousand residents
Or, 875.5 square feet of indoor space per person. This is largely dominated by residential and office space, which are highly favorable for high density construction.

Now, let's consider what a "walkable distance" is for an average person. I'm very happy to walk anywhere within a 10-minute radius (1/2 mile), but can probably live with 20-30 minutes if there is good bike infrastructure. For now let's just discuss the walking case. A 1/2 mile radius is 0.78 square miles, so a perfectly walkable space would contain all of the services I need within 0.78 square miles, or 21.7 million square feet.

How many people can we fit? Filling all of this space with single-story structures would allow us to fit 25,000 people. There are some obvious adjustments we need to make. First, we can realistically build 3 or 4-story structures for residential and office space. Next, we have to adjust for necessary road infrastructure (emergency services, delivery, waste management, etc). New York City dedicates around 50% of its land to roads and open spaces. Using suburban road densities, we can spend 10% of our land on simple 2-way streets. The remaining 90% can be spent on buildings and outdoor space. Let's say we dedicate 30% of the total land to buildings (6.5 million sf), which leaves 60% outdoor space (13 million sf). This is a fairly comfortable estimate based on looking at a map of my college campus. How many people can we fit? Let's assume some densities:

  Residential: 4-story buildings
  Retail: 1-story (could possibly go 2, but makes delivery logistics harder)
  Office: 4-story
  School: 2-story
  Infra: 1-story
The footprint requirements per thousand people are:

600k/4 + 50k + 157.5k/4 + 48k/2 + 20k = 284k square feet per thousand residents

This means our 60% open, fully-walkable space can support a bit over 23,000 people, for a population density of 29k per square mile. For reference, this is slightly higher than New York City.

So, what happens when we bring parking space back into the mix? A 150-car parking lot requires an acre of space, or about 300 sf of parking lot per car. Imagine your city needs two parking spaces per car (one for home, one for work). Even if each family of 4 owns just one car (this seems like quite an underestimate), the parking requirement for our city of 23,000 people is 11,500 spaces. This amounts to 3.45 million square feet of pavement alone, just for parking! In other words, 0.123 square miles of our 0.47 sq.mi. walkable area is now parking lot. Now, how much extra road do we need to facilitate moving all of these vehicles? I'd estimate we need to dedicate at least as much extra space for driving as we do for parking, so now 0.25 square miles (53%) of our outdoor space is now dedicated to personal vehicles. Sure, Amdahl's law of parking infrastructure allows us to reclaim half of this space back if we decide to build multi-story parking structures or hide them underground, but this is a huge waste of resources considering that our city doesn't even need passenger transport of any kind!

In summary: Using some very conservative estimates and medium density, a walkable circular area of 1/2 mile radius (0.78 square miles) can quite comfortably fit 23,000 people with adequate space for residence, office, retail, schools, and remaining city infra. If we dedicate 10% of the land for minimum-necessary roads (emergency services + transportation of goods and waste), we still have 60% of the land remaining for green open space and walking. If we want to add cars, we easily lose over half of this walkable space to parking and additional road. In all of these estimates, I tried to favor cars as much as possible.

stopping··on South Korea now has 11M 5G subscribers
Do you have a citation for "harmful" non-ionizing effects? As far as I can tell, the body of literature has no conclusive evidence to suggest that radio waves do anything but heat the tissue that absorbs it.

Rant: Like many things that receive attention on popular and social media, agonizing over 5G distracts from issues that cause real provable widespread harm, such as UV radiation and air pollution. We rarely see articles rise to the top when they cover non-controversial points that would do well to be read by everybody, because how much buzz and discussion can you generate from "wear sunscreen", "don't drive while tired", and "get a prostate exam before you turn 50"?

stopping··on The YouTube ban is un-American, wrong, and will backfire
Meh, I'm not impressed. Of the dozen or so sources I looked at, half them are links to articles on right-leaning news sites or tweets parroting speech from Trump lawyers, with no links to primary documents. This isn't evidence.

One source was a video of election workers moving boxes around, with a conspiratorial narrative overlaid. This isn't evidence.

Several tweets showing "voting spikes" in favor of Biden as a result of regular counting operations. Nothing wrong here.

The remaining sources discuss "irregularities of expectation", yet none provide any plausible narrative of wrongdoing. The most plausible explanation is that it Democrat-favored voting methods were more streamlined, reliable, and less contested this year compared to years previous. Obviously this nets more votes for Democrats, but nothing practical is stopping a Republican from voting by mail, either. Also, I wouldn't be shocked if the 2020 election was actually more fair than in previous years, due to a large decrease in wrongfully-rejected ballots. I wouldn't be surprised if more Democratic votes were thrown away wrongfully in 2016 than fraudulent Democratic votes were accepted in 2020. If you're concerned about the legitimacy and fairness of U.S. elections, you can't talk about voter fraud while ignoring historical voter disenfranchisement. If someone thinks that mail-in voting was too easy this year, then their gripe is with the judicial systems that permitted this year's election rules.

Conclusion: The linked website doesn't seem to have very high standards of verification, as most items are obviously flimsy or easily debunkable.

stopping··on South Korea's fusion device KSTAR runs for 20 seconds at 100M degrees Celsius
My comment wasn't very focused, so I'll clarify: GP seemed to imply that there is some hidden risk about fusion power that nobody is aware of or talking about, as if such a risk is the greatest factor currently bogging down fusion research. I wanted them to expand on that thought, as it's definitely not a perspective I'm familiar with.
stopping··on South Korea's fusion device KSTAR runs for 20 seconds at 100M degrees Celsius
What conceivable risk could there be that supports this hypothesis?
stopping··on The Vale Programming Language
I think you are severely overestimating the negative repercussions of "too many pet projects" existing in the world. If anyone gets left in the cold because they depended on a project that a maintainer gave up on, then that's a valuable lesson that needs to be learned early in one's career.

I argue that, for most small projects, the net educational value of bringing an idea to fruition in public is far greater than any negative externality that such a project imposes. Imagine a world where every side project by a novice engineer is ruthlessly speared to the point of abandonment. I'm sure your counter-argument is that "trial by fire" is the most effective means of growth. You probably believe that forcing people to give up leads them to consider bigger and better things. This is, by far, not the case. Most people give up, and never come back. You are focusing far too much on the immediate value of the project, and completely dismissing its value as a means of creating a motivated, learned individual who can potentially make huge contributions in the future.

Anyway, if your most salient point is "the author should be more explicit about a support plan", then I don't disagree. But man, you could have presented it in a much more accessible and succinct way. If you really care about people taking your advice to heart, you have to be more kind.

stopping··on The crisis isn’t too much polarization. It’s too little democracy
I've never found this to be a convincing argument in favor of the electoral college as implemented. Why favor a system which constantly cedes power to the same small arbitrary electorate (swing states), year after year?

States should allocate electors in proportion to their own popular votes. The +2 electors for each state is already a good mechanism for combatting pure majority rule. At this point, swing state influence is arguably worse for this country than majority rule.

http://archive.fairvote.org/e_college/reform.htm#proportiona...

stopping··on The crisis isn’t too much polarization. It’s too little democracy
I agree that no electoral system should favor 100% majority rule. But as far as federal republics go, ours is exceptionally prone to abuse, to the point that political chicanery is often more effective than good public policy.
stopping··on Keep the nuclear launch codes in an innocent volunteer's chest-cavity (2015)
As far as we know, the earth is a globe. What point are you trying to make?
stopping··on Keep the nuclear launch codes in an innocent volunteer's chest-cavity (2015)
This is essentially false. There are several redundant safety and security mechanisms protecting nuclear weapons, one of which is the Permissive Action Link (essentially a combination lock on the warhead). This is the component in question which once had the alleged code of 00000000: https://web.archive.org/web/20120511191600/http://www.cdi.or...

The "nuclear football" is a completely separate authentication mechanism for verifying a presidential order, and as far as we know uses codes that rotate on a daily basis.

stopping··on A 28-year-old with no degree becomes a must read on the economy
There may be lots of free opinions, but I don't believe they have much value to the novice investor. I'll admit there are some hidden gems, but separating the wheat from the chaff requires more insight than these subreddits provide on average.
stopping··on I was blackmailed – any YouTuber could be next
Yeah, your original point was very fair; GP probably didn't mean for his statement to be interpreted as its inverse, which I jumped the gun on. My reasoning was that if the inverse wasn't implied, then the overall conclusion should simply be "all companies should provide exceptional customer service".

I also probably should have more charitably interpreted GP as "companies in a strong position have a better ability to provide good customer service."

stopping··on I was blackmailed – any YouTuber could be next
Small clarification: I'm assuming that shareholder obligation is the predominant force upon corporate governance, not the only one.

But, point taken.

stopping··on I was blackmailed – any YouTuber could be next
Allow me to clarify: The word "charity" is used in the perverted capitalistic sense, where Google's predominant "duty" is first and foremost to its shareholders. The capitalist incentive structure requires no more than the bare minimum of customer service from Google.

I agree that Google has a moral duty to take care of the people who choose to put their trust in their platforms.

stopping··on I was blackmailed – any YouTuber could be next
IMO, Google's profit per employee isn't an indicator of Google's obligation to increase its customer service headcount. Taken to it's logical conclusion, we should let poorly-performing companies off the hook for having awful customer service.

The rest of this comment is going to be somewhat critical of Google criticism and seemingly apologistic. Please assume positive intent.

I agree that Google certainly could do more to help people on its platform. But this will always be the case until every single customer service issue is solved to the user's satisfaction. The important question that I never see anybody asking or answering is "How much is reasonably enough, and how do we know (subject X) has done enough?"

It all boils down to what we believe the moral obligation of people (and companies, by extension) ought to be. Any extra service that Google provides beyond those required for profit maximization (e.g. customer retention, maintaining reputation, being only slightly better than the second-best option) is purely charity. Then, how do we evaluate when a certain amount of charity is sufficient, let alone necessary? Public sentiment is fickle, and therefore not a great measure. I bet even if Google increased its CSR by 10x, we'd still see communities eagerly latch onto any criticism of the tech giant and shout "you have to do more!" without quantifying what the final demand actually is!

I take the moral position that we as a society certainly can and should do much more to take care of each other. Telling each other to be better is absolutely valuable and I will never argue against that. But I believe we ought to do a much better job of suggesting desirable and realistic end states, instead of perpetuating insubstantial discourse amounting to one of either "They need to do better!" or "Come on, they're doing the best they can."

Admittedly this places me in a non-committal position. I don't have any great suggestions for what the end states of YouTube, Twitter, et al should look like from a content moderation perspective. But I would love to hear input from actual experts in who can offer some reasonable ideas about the most cost-beneficial solutions for society as a whole.

stopping··on Ask HN: What scientific phenomenon do you wish someone would explain better?
It's not so much "magic" as it is the sheer rate of molecular collisions in the cytosol. There are so many collisions happening that at least one of them will do what you want. Here's a back-of-the-napkin example, admittedly with many simplifications:

A tRNA molecule at body temperature travels at roughly 10 m/s. Assuming a point-sized tRNA and stationary ribosome of radius 125 * 10^-10 m, the ray casted by the moving tRNA will collide with the ribosome when their centers are within 125 * 10^-10 m of each other. The path of the tRNA sweeps a "collidable" circle of the radius of 125 * 10^-10 m, for a cross-sectional area of 5 * 10^-16 m^2. Multiplied by the tRNA velocity, the tRNA sweeps a volume of 5 * 10^-15 m^3 per second. Constrained inside an ordinary animal cell of volume 10^-15 m^3, the tRNA would have swept the entire volume of the cell five times over in a single second. Obviously the collision path would have significant self-overlap, but at this rate it's quite likely for the two to collide at least once any given second.

Now, consider that this analysis was only for a single ribosome/tRNA pair. A single ribosome will experience this collision rate multiplied by the total number of tRNA in the cell, on the order of thousands to millions. If a ribosome is bombarded by tens of thousands of tRNA in a single second, it's very likely one of those tRNA will (1) be charged with an amino acid, (2) be the correct tRNA for the current 3-nucleotide sequence, and (3) collide specifically with the binding site on the ribosome in the correct orientation. In actuality, a ribosome synthesizes a protein at a rate of ~10 amino acid residues per second.

Any given molecule in the cell will experience millions to billions of collisions per second. The fact that molecules move so fast relative to their size is what allows these reactions to happen on reasonable timescales.

stopping··on Stanford cancels in-person classes for rest of the quarter
How would you characterize the current public response to COVID-19? What aspects do you think indicate under-preparation? What aspects do you think are hysterical or overly cautious? To what extent do you believe it is prudent and reasonable to shut down businesses, schools, and other public places to prevent the spread of the disease? How do you weigh the cost of constricting economic and social activity compared to the cost of the disease itself?

Anybody who is willing to pass (IMHO) bad-faith judgments on well-intentioned users should be also willing to answer these sorts of questions.

stopping··on DoorDash has filed for IPO
Not to mention that the in-app menu prices are frequently inflated compared to dining in. To be fair, I believe this is set by the restaurant in order offset the huge cut that delivery apps take.
← PreviousPage 4 of 4