I was surprised that for almost 300 pages there were only 26 references listed in the back. Not the end of the world by any means, clearly a ton of work went into this, but I find it useful to see from references how it overlaps with other subjects I may know more about
There was an auction of a lot of his memorabilia a few months ago, it included a lot of Festool stuff. He was an avid woodworker (the sale also included furniture he made). I like how the work table where you can see the miter saw is made of the most utilitarian plywood, it feels like he was working until his last days
I was expecting a mention of symplectic ODE solvers, although perhaps that was beyond the scope of the blog post. For Hamiltonian ODEs, you can design methods that explicitly preserve energy, outperforming more generic methods.
Yeah, that's a separate post https://scicomp.stackexchange.com/questions/29149/what-does-.... I wanted to keep this post as simple as possible. If you could show cases where explicit Runge-Kutta methods outperform (by some metrics) implicit Runge-Kutta methods, then it leads to a whole understanding of "what matters is what you're trying to measure". And then yes, symplectic integrators are for long time integrations (explicit RK methods will how lower error for shorter time, so its specifically longer time integrations on symplectic manifolds, though there are implicit RK methods which are symplectic but ... tradeoff tradeoff)
Saw once a discussion that people should not have kids as it's by far the highest increase in your carbon footprint in your lifetime (>10x than going vegan, etc) be driven all the way to advocating genocide as a way of carbon footprint minimization
> Saw once a discussion that people should not have kids as it's by far the highest increase in your carbon footprint in your lifetime (>10x than going vegan, etc) be driven all the way to advocating genocide as a way of carbon footprint minimization
The opening scene of Utopia (UK) s2e6 goes over this:
> "Why did you have him then? Nothing uses carbon like a first-world human, yet you created one: why would you do that?"
Setting aside the reductio ad absurdum of genocide, this is an unfortunately common viewpoint. People really need to take into account the chances their child might wind up working on science or technology which reduces global CO2 emissions or even captures CO2. This reasoning can be applied to all sorts of naive "more people bad" arguments. I can't imagine where the world would be if Norman Borlaug's parents had decided to never have kids out of concern for global food insecurity.
It also entirely subjugates the economic realities that we (at least currently) live in to the future health of the planet. I care a great deal about the Earth and our environment, but the more I've learned about stuff the more I've realized that anyone advocating for focusing on one without considering the impact on the other is primarily following a religion
> It also entirely subjugates the economic realities that we...
To play devils advocate, you could be seen as trying to subjugate the worlds health to your own economic well-being, and far fewer people are concerned with your tax bracket than there are people on earth. In a pure democracy, I'm fairly certain the planets well being would be deemed more important than the economy of whatever nation you live in.
> advocating for focusing on one... is primarily following a religion
Maybe, but they could also just be doing the risk calculus a bit differently. If you are a many step thinker the long term fecundity of our species might feel more important than any level of short term financial motivation.
> To play devils advocate, you could be seen as trying to subjugate the worlds health to your own economic well-being, and far fewer people are concerned with your tax bracket than there are people on earth.
Well, if they choose to see me as trying to subjugate the world's health to my own economic well-being (despite the fact that I advocate policies that would harm me personally in the name of climate sustainability), then we're already starting the discussion from bad faith (literally they are already assuming bad faith on my part). I'm at the point where I don't engage with bad faith arguments because they just end up in frustration on both sides. This whole modern attitude of "if you disagree with me then you must be evil" thing is (IMHO) utter poison to our culture and our democracy, and the current resident of the White House is a great example of where that leads.
> In a pure democracy, I'm fairly certain the planets well being would be deemed more important than the economy of whatever nation you live in.
Yeah, for about 3 days until people start getting hungry, or less extreme, until they start losing their jobs and their homes, or even longer term when they start to realize that they won't be able to retire and/or that they are leaving their kids a much worse situation than they themselves had (much worse than the current dichotomy between Boomers and Millenials/Zoomers). Ignoring or disregarding Maslow's Hierarchy of Needs is a sure way to be surprised and rejected by the people. We know that even respectable people will often turn to violence (including cannabalism) when they get hungry or angry enough. We're not going to be able to save the planet if there's widespread violence.
> Maybe, but they could also just be doing the risk calculus a bit differently. If you are a many step thinker the long term fecundity of our species might feel more important than any level of short term financial motivation.
I think this actually pointed at our misunderstanding (I know you're playing devil's advocate so this isn't addressed to you personally, rather your current presentation :-) ). I'm not talking about short-term financial or even economic motivation. I'm looking medium to long term, the same scale that I think needs to be considered for the planet. Now that said, banning all fossil fuels tomorrow and causing sweeping global depression in the short-term is something I would radically oppose, because it would cause immense suffering and I don't believe it would make much of a dent in the climate long-term (as it would quickly be reversed under the realities of politics) and it would absolutely harm the lower income brackets to a much greater proportional extent than the upper income brackets who already have solar panels and often capable of being off-grid. Though, even they will still run out of food when the truck companies aren't able to re-stock local grocery store shelves...
> I'm at the point where I don't engage with bad faith arguments because they just end up in frustration on both sides.
I agree, and that's almost exactly why I replied to your statement that anyone who saw it differently than you did was "just following a religion" (to slightly paraphrase). They aren't, they just have a different perspective on the situation and have just made different calculations regarding the risk/reward ratio.
> Ignoring or disregarding Maslow's Hierarchy of Needs is a sure way to be surprised and rejected by the people.
>I'm looking medium to long term, the same scale that I think needs to be considered for the planet.
I don't think they ARE ignoring Maslow's hierarchy. It seems to me, that they just see the environmental destruction as being a more immediate concern than you do. You seem to have a "we'll fix it when it's more convenient" stance. That doesn't work for the folks who believe we'll all be starving within a decade or less, or who believe that it will NEVER be more convenient. To them this is near the top of the hierarchy.
At the end of the day, I'm very much on your side of the argument. I think we do have some time to sort it out, and I suspect that we will eventually make significant progress towards those goals (despite modern Republicans Ostrich based approach to risk). However, I understand why other people disagree, and I respect that. There's even some science that agrees with the "sky is falling" crowd. It's certainly not a totally irrational stance.
Not everyone believes that the purpose of life is to make more life, or that having been born onto team human automatically qualifies team human as the best team. It's not necessarily unfortunate.
I am not a rationalist, but rationally that whole "the meaning of life is human fecundity" shtick is after school special tautological nonsense, and that seems to be the assumption buried in your statement. Try defining what you mean without causing yourself some sort of recursion headache.
> their child might wind up..
They might also grow up to be a normal human being, which is far more likely.
> if Norman Borlaug's parents had decided to never have kids
Again, this would only have mattered if you consider the well being of human beings to be the greatest possible good. Some people have other definitions, or are operating on much longer timescales.
> People really need to take into account the chances their child might wind up working on science or technology which reduces global CO2 emissions or even captures CO2.
All else equal, it would be better to spread those chances across a longer period of time at a lower population with lower carbon use.
Beyond efficacy, having a drug that only needs to be taken twice per year is a huge deal. Adherence is critical for treatments to succeed, and it's much easier to ensure that patients are on their meds twice per year. It's also much safer for vulnerable people, where getting caught with HIV medications (say daily pills) could be dangerous
That's like saying jet engines are banned in IndyCar. Umm . . . yeah? Because they're competing to see who makes the best SMOKED meat, and sous vide would be using the wrong cooking technique.
Membership filters are very efficient filters that guarantee no false negatives, but false positives are possible (how much and how many can be adjusted based on the dataset and filter's parameters). An obvious application could something like checking whether passengers are in a no-fly list, where false-positives could be handled by further checks. As far as I know cuckoo filters [0] are the state of the art for this, but per this work in principle you could make very efficient with using a SAT (or XORSAT) solver that could generate many feasible solutions out of random SAT problems.
- Google scholar pointed out this link to get a pdf for one of the papers cited in the repo [1]
> An obvious application could something like checking whether passengers are in a no-fly list, where false-positives could be handled by further checks.
Why is this an obvious application? How does this application benefit from a "very efficient" first pass? Just the boarding process on an airplane takes 20-30 minutes; you can easily check the entire passenger manifest in an error-free way in much less time than that. People have to buy their tickets before the boarding process begins.
If 99% of people aren't on the list, and 1% are, if your check is super fast but makes 1% false positives, you still end up having to only do a full check on 2%. Which could be a huge huge huge win computationally.
Your post is really weird to me, talking about boarding times? You start skeptical of the example & I'm confused how you think this is anything but a fine example. Ultimately there's some service running in the cloud somewhere that needs to have checks run against it. 2.9m people fly a day in the US, and whether the servers doing that work can do it efficiently or whether they do it in a dogsbit bad manner seems like an obvious concern to me? https://www.faa.gov/air_traffic/by_the_numbers
I suspect the actual usage for this is for much broader higher traffic systems. For things that watch sizable chunks of the internet for patterns and traffic. But checking passengers against. I fly lists sounds like a pretty reasonable example use to me, and the criticism seems off base & weird in a number of dimensions that straight up don't make sense.
Congratulations on re-highlighting my greatest complaint about your qualm-making, a propensity for adding factors into the mix that have nothing to do with the big picture.
To me, 47 or 37 req/s seems like a fantastically immaterial difference. It's just not a big enough change in magnitude to really affect the situation.
Accurate qualm, and being technically correct. Personally I'd try to find a more liberal minded approach when trying to hold in my mind the question for what efficient set membership might be good for.
The change in magnitude is over 20%; if you're thinking about it in terms of "change in magnitude", it's huge.
As FridgeSeal points out, both numbers are very small, but that's not a reason you'd want to set up an inaccurate triage system on top of the accurate one. If you don't have very much work to do, you don't need to invest much in optimizing it.
Most airports are not open 24/7 in the sense that flights are departing 24/7 or that you can get through security checkpoints 24/7. They simply don't kick people out of the secure area when they shut down. You'll still have difficulties showing up to your 5am flight 3 hours early before the checkpoints open at most major airports.
You have difficulties showing up to your flight three hours early because checkin is not available that far in advance. But the airport obviously is open that far in advance. Planes are departing and landing at that time. The checkin counter may be open (or may not; volume does go down).
It it likely true that "most airports" are not operating 24/7, but how is that relevant? It could be just as true that "most airports" don't serve commercial flights at all. The airports that have a lot of passengers are operating 24/7. We're talking about a metric assessed per passenger.
I'm not talking about the check-in counter, I'm talking about general security that non-charter passengers always have to go through to board a flight. Security checkpoints operate limited hours at even the largest airports, like LAX where they're open from 4h00-22h00 max. If we look the departures for LAX today, we can see that no passenger planes departed between 2h00-5h00, except for one charter jet out of the private terminal. Yesterday had no such departures, only the usual nighttime cargo flights.
The false-positive check is trivially just comparing the given key to the key at the resulting index. Trivial.
The only size problem is with non-ordered MPHF's where you need to reference the index through an index order table also.
The SAT approach is cute, but doesn't scale. It might have better runtime costs as you can spare one additional table lookup. Efficient MPHF's are miles better at construction time.
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