If you're going to cite a YouTube video of TV news as your source... I hardly know what to say.
Any large dog can be dangerous. They are, after all, carnivorous predators. Proper training and handling are the key responsibilities of any owner of a large dog.
So spare us the clickbait, and before you go quoting some unrefereed published number of bites by breed, at least do some rudimentary arithmetic and divide by the number of dogs of each breed in the sample population. So-called "pit bulls" are the most popular dog breeds in the United States, far outnumbering any other single breed.
The article is a little bit breathless about this work as though evidence of solar system instability is completely novel and unexpected, but investigation in the area using simulation isn't exactly unprecedented.
Gerry Sussman and Jack Wisdom were working on the question of solar system instability in the late 1980s and Sussman and his students built a specialized computer called the Digital Orrery at MIT. They ran some very long simulations and found strong numerical evidence that the orbit of Pluto is chaotic.
The point the article (apparently unsuccessfuly) tries to hammer home is that the findings here are mathematical, they go beyond simulation and take a deeper bite into the problem, proving that all planetary systems are unstable.
The first paragraph of the linked article talks about simulation experiments from 2009, so your criticism here that there is some spurious claim to novelty is pretty unfounded. Simulation runs that show instability are old hat; mathematical proof that this instability is inherent and unavoidable is the story.
The article implies this is what was proved, but later contradicts itself. Based on my reading, only a couple specific initial conditions were proved to be unstable.
Yep. Quantum chaos, at least insofar as I was involved with it, is about semi classical analysis of quantum systems which would have chaos if they were classical.
Remember quantum mechanics started with the Bohr atom which was an approach that would generalize to any system that has quasi periodic (solar system in the short term) dynamics. Circa 1917 Einstein wrote a paper that said that this approach wouldn’t generalize because Poincaré proved that chaos is generic, soon after that we got Schrodinger’s equation and similar approaches. (Although that Einstein paper killed a line of development it barely got cited for 50 years)
Later on there were mathematical developments in quantum chaos such as Gutzwiller’s trace formula and also numerical work where people discovered various properties of the quantum levels of systems that were classically chaotic.
Linear operators in quantum mechanics don’t precluded observing chaos in the real world because the true “long term” is very long indeed. That is, classically or quantum mechanically if you wait some really absurdly long time (say much more than 10^120 years) the universe is expected to come arbitrarily close to the state it is in today. See
Though note that the recurrence theorem applies to a finite phase space. An expanding universe such as ours is not subject to that. We just get heat death instead.
These are numerical simulations though. The novelty is the proof that these instabilities don't come from numerical artifacts, but are an inherent part of the system.
There’s no doubt at all that there is some chaos in the solar system (e.g. you can’t quite predict which side of the sun the Earth will be on in 100 million years) but the question is does something big happen, like a planet getting ejected. In a low number of configuration space dimensions (N=2) you get “KAM tori” in phase which are an absolute barrier to the evolution of the system so chaotic motion is hemmed in. In N>2, however, KAM tori are still there but it is possible for chaotic trajectories to go around them. It’s clear that the trajectories of the planets behave like KAM tori on short timescales (1000s of years, that is how each one seems to be on an independent stable orbit) but what happens in the long term is not clear at all.
People developed these great environments like EMACS and other open source software out of passion, not because they were chasing profits. There are many instances where seeking profits, as in the corporate world, reduces innovation and creates a short term mindset. A lot of the best research comes out of state-funded labs, even the development of the transistor and the computer in the USA, the development of the internet, all funded by the state.
You're painting with broad a brushstroke. Both good and bad things
emerge from the public and private sectors. Despite often falling into
the "worse is better" trap, self-interest is our species' most potent
innovator, modulo purgative events like WW2 when all our intellectual
capital returned to the state.
To be fair, FOSS is pretty much the definition of socialism. Donations are pretty much the only way money is made directly off the software itself. Running an instance of the software, if it's a server for example, is a slightly different story. Everyone contributes of their own volition and interest.
I'm not a fan of government-enforced socialism or communism. But if you can get enough people together to willingly participate independently, I'm chill with it. And FOSS software is an example of it working out alright.
> the definition of socialism. Donations are pretty much the only way money is made
That's not the definition of socialism at all.
If you think about it, it's actually much closer to the principle of right-wing Christian charity rather than the left-wing sharing of means of production.
Many in the US tend to associate Christianity with right-wing ideology, but there's actually quite a few examples of a varied history of left-wing Christian thought and action. Sticking to US history: Reverend Martin Luther King, Jimmy Carter, Dorothy Day (https://en.wikipedia.org/wiki/Dorothy_Day).
Outside of the US, Liberation Theology in Latin America was an ideology/movement explicitly linking Christian (mostly Catholic) teachings with Marxist-inspired struggles for workers' rights (sometimes those links are easy to do, if you focus on quotes such as "blessed are the poor").
I do agree that FOS software is not socialism, and that donations aren't socialism. But it's important to note that many people who work on FOS software do so without expecting anything in return. I think that idea is in sharp contrast with typical right-wing and centrist economic theories that view human beings as mostly money-driven, self-centered individuals.
We're falling in the pitfall of ‶left and right are different depending on where you're standing″. I'm 100% sure what you say is true in your country; but in mine, being religious and eschewing the state-based, tax-backed wealth redistribution in favor of the personal, charity-based one definitely puts you as left-wing.
Christianity is fully compatible with a society where people can make meaningful decisions over things which affect them, with democratic control their workplace and community. In fact Tolstoy came to this conclusion, that Christian ideology says we should have no bosses, and not dominate or control other people.
I suppose there are various right-wing ideologies, and some of them may be compatible with Christianity. I cannot imagine any left-wing ideology (which is at best wrong and at worst downright evil) compatible with Christianity.
Rather than of socialism, I’d say FLOSS is a form of (digital) commons, which as GP points out, is a pre-capitalist/non-capitalist form of production and management.
thats a good point, probably people are colloquially using socialism to mean "the opposite of capitalism", but what it really is just one of many alternatives
on that usage then i think the proper wording for "the opposite of capitalism" would be something like non-capitalist (or even anti-capitalist maybe?)
Socialism can mean a lot of things. But originally it meant the control and management of society by workers, on a democratic basis, including the workplace.
"Senior House has always had a heavy contingent of counter culture types, much more so than other dorms at MIT," -- ha ha. They nuked Bexley first for a reason. Ghetto -- suburb!
You make some specific claims here that sound a little odd to this LISP and assembly language hacker.
Assembly language doesn't provide any datatypes. LISP does. Assembly language doesn't provide any type checking. LISP does. Assembly language doesn't provide automatic storage reclamation. LISP does. Assembly language doesn't provide naming. LISP does.
You also make a claim about L1 caches and locality of reference. Every LISP compiler writer, and every LISP garbage collector writer, knows about CDR-coding. We also know about how Cheney copying garbage collectors and their descendants like the Baker incremental collector compact data, precisely for locality of reference. The compiler writer of course is thinking about cache performance and how lines are mapped in particular target architectures.
You should probably educate yourself a little more about LISP if you are so interested in it as to make statements in a public forum.
He was talking about macro assemblers, which often do provide naming and some level of type checking (and pure assembly is arguably at a lower level of abstraction than type systems, with separate instructions and registers for integers, pointers, floating-point etc).
I agree it's a somewhat odd comparison.
There are of course plenty of obvious and non-obvious ways to optimize linked lists, but even still they have poor performance characteristics, space efficiency and cache locality compared to alternative structures like arrays and even immutable arrays.
There's a reason Java, C#, Python etc store strings as immutable arrays; not only do they start from a generally better performance baseline than lists, but they too have well-understood optimization characteristics.
I was only talking about the 'list of function calls' aspect of assembler and Lisp, not the type system. I agree that Lisp has a type system and assembler doesn't. Forth is another language that also has very simple syntax that approximates the 'list of function calls' style that I would say isn't unlike a macro assembler either.
I am writing a new language with built-in garbage collection that I think is quite superior to other languages. I have created a full standard library with almost 1,000 built-in functions and none of my data structures (lists, maps, trees, stacks, indexes, tables etc) contain pointers or linked lists (that use pointers). I sold over 30,000 copies of a language/database system in 1987 so I think your last comment is quite inappropriate. I have know about Lisp since I started CS in University in 1975.
Linked lists are horrible data structures when being used as well as when being freed (your garbage collection comment). I use simple dynamic multi-typed arrays instead of linked lists (pointers) and they can be freed in 1 chunk or a bigger version can be freed with a few memory de-allocations. I get full cache locality and improved speed of allocation and de-allocation.
I would love to see an incremental GC that can copy all linked lists nodes into contiguous memory automatically. Nice trick if you can do it but that doesn't help you if your linked list doesn't cause a GC.
Big time array fan here. I'd love to check out your language when you publish it. Sooner the better.. we need new ideas! Email in profile if you'd like to chat about it.
According to the article, Dr. Reiffel said, 'The Air Force wanted a mushroom cloud so large it would be visible on earth.'
That seems a very odd thing for a physicist to say, given that of course a mushroom cloud wouldn't form in a vacuum. Perhaps Dr. Reiffel was not at his best on the day of the interview?
There are too many impossibilities and errors in this to even consider it as remotely factual.
- ICBMs can't reach the moon, or even anything remotely close to it
- Mushroom clouds don't form in a vacuum.
- The fact that some Air Force officer thought it would be a neat idea (if any of this is factual) does not in any way imply that it was even remotely considered by anyone with the authority to make such a decision, any more than seeing a person who works at the Apple store drinking a coke implies that Apple Inc is buying the entire CocaCola corporation.
By "mushroom cloud" they must have meant the ball of dust thrown up by an explosion at/below the lunar surface. That is why Sagan would have suggested it as a possibility for detecting micro-organisms.
But it still wouldn't make a cloud, it would just scatter dust, and each particle of dust would fall back to the moon in a ballistic trajectory (it would not last long at all).
I completely agree. I'm surprised that the HN community, which so often points out poor science in other articles, in this case seems to include a lot of people posting personal anecdotes about their diets.
For those people, I think it's very nice that you had a good experience dieting. Your story isn't science however, and the rest of us aren't going to learn anything generalizable from it. Perhaps you should be posting to a reddit support group?
Umm, does anybody else cringe at the public documentation of this person's problems? The author hasn't spoken to her brother since 2013 -- so how does she know he wants his problems to be made public to all the world? She even gave his full name.
Though she hasn't spoken to him, that doesn't necessarily mean that she hasn't received permission by some other means (e.g. by letter or via third party).
She made a comment in the Verge forums clarifying that she did in fact have his permission.
That was my thought constantly through reading this. I agree wholeheartedly that we need to spend more on rehabilitation and treatment and it sounds like this facility is doing good work but laying your sibling's (a sibling you haven't talked to in years and even when you did they weren't the person they are now) life bare like this feels like a huge invasion of privacy as well as possibly having a negative impact on the brother when he does find out about it. Not to mention this will now follow him for the rest of his life as a very public record of his past failings....
Yeah seems really unfair to publish this without talking to him. Hopefully she did.
Also, not to downplay what they've been through, but her brother's transgressions against the family hardly seem worth kicking him out over. He pawned some musical equipment and tried to sneak whiskey into his room, and left a bruise on her arm? For that they permanently kick him out? I realize he broke into other people's homes and stole from them, and that sucks but he's also paid for those crimes.
Maybe she's leaving out some things he did, I don't know. But to me this article reads like she and her parents are harder on her brother than he deserves. Hopefully it all works out.
Allowing a criminal to live in your house puts the whole family at risk. What if he does something that prompts the police to SWAT him, and by extension you? And then there is asset forfeiture; people have lost their homes because their adult child that lived with them got busted with drugs.
If I had a family member that was up to that kind of shit, I might help them pay rent in a home of their own, but they would not be staying in my home.
It's more like you're the one leaving things out; she pretty clearly describes how this is representative of patterns of behavior persisting for years and years.
Yeah, one of the links in that article was to another one she wrote about him, so it seems she plans on getting a lot of mileage out of his misfortune despite not really being in contact with him.
She certainly has the free-speech right to write whatever she wants to. It's just not the way most families treat each other - certainly my brother wouldn't write this about me, and vice versa - so it's uncomfortable to read. Either it's fictionalized, or it's a crappy way to treat your brother.
The story is a reported memoir that touches on a number of topics. The first, primarily, is about the treatment facility that takes care of people like her brother. Another is the negative and traumatic effects that addicts have around the people like them. In no way is this article about the brother but rather the effects of the brother to the world around him.
Often times, family members rely on arguments about the proper ways to behave to each other in order to silence or police objections to family behavior. In the case of addiction, it is complicated because addiction is itself complicated in ways that other forms of trauma are perhaps not. That said, is the voice of people who were traumatized by others worth less? Should it be kept quiet simply because the other person is a member of the family? Are we not allowed to acknowledge and discuss that addicts cause trauma for people around them that is deeply hurtful and is allowed to be heard as well?
It isn't; it just seems like a really shitty thing to do to someone you care about. If indeed she does, but the conditional love of women often works out this way.
Imagine the opposite case; her brother is wildly successful, but still has a drinking problem. In this instance, she and her parents would probably shower him with love and affection. "We will get through this together!"
Pretending there isn't political economy in familial relationships is pretty naive. Especially when female relatives are concerned.
If you're going to cite a YouTube video of TV news as your source... I hardly know what to say.
Any large dog can be dangerous. They are, after all, carnivorous predators. Proper training and handling are the key responsibilities of any owner of a large dog.
So spare us the clickbait, and before you go quoting some unrefereed published number of bites by breed, at least do some rudimentary arithmetic and divide by the number of dogs of each breed in the sample population. So-called "pit bulls" are the most popular dog breeds in the United States, far outnumbering any other single breed.