Osias Jota

The week before last, I was in Rio de Janiero to give a mini-course on “Complexity Theory and Quantum Optics” at the Instituto de Física of the Universidade Federal Fluminense.  Next week I’ll be giving a similar course at the Jerusalem Winter School on Quantum Information.

In the meantime, my host in Rio, Ernesto Galvão, and others were kind enough to make detailed, excellent notes for my five lectures in Rio.  You can click the link in the last sentence to get them, or here are links for the five lectures individually:

• Lecture 1: The Extended Church-Turing Thesis
• Lecture 2: Classical and Quantum Complexity Theory
• Lecture 3: Linear Optics and Exact BosonSampling
• Lecture 4: KLM, Postselection, and Approximate BosonSampling
• Lecture 5:  Scalability and Verification of BosonSampling Devices

If you have questions or comments about the lectures, leave them here (since I might not check the quantumrio blog).

One other thing: I can heartily recommend a trip to Rio to anyone interested in quantum information—or, for that matter, to anyone interested in sunshine, giant Jesus statues, or (especially) fruit juices you’ve never tasted before.  My favorite from among the latter was acerola.  Also worth a try are caja, mangaba, guarana, umbu, seriguela, amora, and fruta do congi juices—as well as caju and cacao, even though they taste almost nothing like the more commercially exportable products from the same plants (cashews and chocolate respectively).  I didn’t like cupuaçu or graviola juices.

OK, agora que já tenho a sua atenção, vamos ao samba do crioulo sueco que é esse filme. Ele tem:

• Louras suecas vikings com metralhadoras
• Saudosismo Anos 80
• Clichês policiais até o talo
• Viagens no tempo
• Hitler
• DeLoreans
• Thor

Ah, e um T-Rex.

“VOCÊS TÊM UM T-REX?”

Yes, um T-Rex.

Veja o trailer:

O projeto já foi quase todo filmado em estúdio na Suécia, agora falta só a grana para parte da pós-produção. A meta é de US$ 200 mil, com isso terminarão o filme, que terá 30 minutos e será distribuído gratuitamente nas interwebs.

A boa notícia é que faltando 27 dias pro término da arrecadação, quase 7 mil pessoas já doaram US$ 265 mil, o que torna a meta estendida de US$ 1 milhão, que transformaria o filme em um longa, viável.

A idéia não é revolucionar a indústria cinematográfica, mas mostrar que é possível sim ao pequeno, minúsculo produtor criar sem depender dos mega-estúdios.

Acho interessante aliás, como nos países ricos o modelo de Kickstarter funciona muito melhor. O sujeito tem a idéia de um projeto, pede pra quem gostar da idéia colaborar, e pronto. No Brasil há a postura de pobre mas orgulhoso. São raros os blogs com botões para doações. Nem querendo o sujeito pode mandar um agrado pro site que tanto gosta. Eu mesmo só coloquei um botão no PayPal no Contraditorium depois que percebi que precisaria de muita verba pro meu projeto de clonar a Luciana Vendramini.

Aqui só se faz vaquinha online para fins nobres. É moralmente aceito que você peça dinheiro para castrar crianças e tirar cachorros das ruas e botar em bancos de escola, mas se seu projeto é entretenimento, você se torna SATÃ. Já vi projetos de gente querendo dinheiro pra publicar livro e a primeira pergunta era “quantos você vai doar”.

Brasileiro precisa amadurecer e entender que empreender não é pecado.

Portanto, palmas pro David Sandberg. Kung Fury pode não ser o filme ideal de um monte de gente, mas agora, graças à internet mesmo um ínfimo segmento de público que goste dessas bobagens terá seu desejo atendido.

The post Kung Fury — O Melhor Filme do Universo, via Kickstarter appeared first on Meio Bit.

FuzzNugget writes "Wired presents this damning perspective on so-called social media addiction: 'If kids can't socialize, who should parents blame? Simple: They should blame themselves. This is the argument advanced in It's Complicated: The Social Lives of Networked Teens, by Microsoft researcher Danah Boyd. Boyd ... has spent a decade interviewing hundreds of teens about their online lives. What she has found, over and over, is that teenagers would love to socialize face-to-face with their friends. But adult society won't let them. "Teens aren't addicted to social media. They're addicted to each other," Boyd says. "They're not allowed to hang out the way you and I did, so they've moved it online." It's true. As a teenager in the early '80s I could roam pretty widely with my friends, as long as we were back by dark. Over the next three decades, the media began delivering a metronomic diet of horrifying but rare child-abduction stories, and parents shortened the leash on their kids. Politicians warned of incipient waves of youth wilding and superpredators (neither of which emerged). Municipalities crafted anti-loitering laws and curfews to keep young people from congregating alone. New neighborhoods had fewer public spaces. Crime rates plummeted, but moral panic soared. Meanwhile, increased competition to get into college meant well-off parents began heavily scheduling their kids' after-school lives.'"

Read more of this story at Slashdot.

[With special thanks to the Up-Goer Five Text Editor, which was inspired by this xkcd]

I study computers that would work in a different way than any computer that we have today.  These computers would be very small, and they would use facts about the world that are not well known to us from day to day life.  No one has built one of these computers yet—at least, we don’t think they have!—but we can still reason about what they could do for us if we did build them.

How would these new computers work? Well, when you go small enough, you find that, in order to figure out what the chance is that something will happen, you need to both add and take away a whole lot of numbers—one number for each possible way that the thing could happen, in fact. What’s interesting is, this means that the different ways a thing could happen can “kill each other out,” so that the thing never happens at all! I know it sounds weird, but the world of very small things has been known to work that way for almost a hundred years.

So, with the new kind of computer, the idea is to make the different ways each wrong answer could be reached kill each other out (with some of them “pointing” in one direction, some “pointing” in another direction), while the different ways that the right answer could be reached all point in more or less the same direction. If you can get that to happen, then when you finally look at the computer, you’ll find that there’s a very good chance that you’ll see the right answer. And if you don’t see the right answer, then you can just run the computer again until you do.

For some problems—like breaking a big number into its smallest parts (say, 43259 = 181 × 239)—we’ve learned that the new computers would be much, much faster than we think any of today’s computers could ever be. For other problems, however, the new computers don’t look like they’d be faster at all. So a big part of my work is trying to figure out for which problems the new computers would be faster, and for which problems they wouldn’t be.

You might wonder, why is it so hard to build these new computers? Why don’t we have them already? This part is a little hard to explain using the words I’m allowed, but let me try. It turns out that the new computers would very easily break. In fact, if the bits in such a computer were to “get out” in any way—that is, to work themselves into the air in the surrounding room, or whatever—then you could quickly lose everything about the new computer that makes it faster than today’s computers. For this reason, if you’re building the new kind of computer, you have to keep it very, very carefully away from anything that could cause it to lose its state—but then at the same time, you do have to touch the computer, to make it do the steps that will eventually give you the right answer. And no one knows how to do all of this yet. So far, people have only been able to use the new computers for very small checks, like breaking 15 into 3 × 5. But people are working very hard today on figuring out how to do bigger things with the new kind of computer.

In fact, building the new kind of computer is so hard, that some people even believe it won’t be possible! But my answer to them is simple. If it’s not possible, then that’s even more interesting to me than if it is possible! And either way, the only way I know to find out the truth is to try it and see what happens.

Sometimes, people pretend that they already built one of these computers even though they didn’t. Or they say things about what the computers could do that aren’t true. I have to admit that, even though I don’t really enjoy it, I do spend a lot of my time these days writing about why those people are wrong.

Oh, one other thing. Not long from now, it might be possible to build computers that don’t do everything that the new computers could eventually do, but that at least do some of it. Like, maybe we could use nothing but light and mirrors to answer questions that, while not important in and of themselves, are still hard to answer using today’s computers. That would at least show that we can do something that’s hard for today’s computers, and it could be a step along the way to the new computers. Anyway, that’s what a lot of my own work has been about for the past four years or so.

Besides the new kind of computers, I’m also interested in understanding what today’s computers can and can’t do. The biggest open problem about today’s computers could be put this way: if a computer can check an answer to a problem in a short time, then can a computer also find an answer in a short time? Almost all of us think that the answer is no, but no one knows how to show it. Six years ago, another guy and I figured out one of the reasons why this question is so hard to answer: that is, why the ideas that we already know don’t work.

Anyway, I have to go to dinner now. I hope you enjoyed this little piece about the kind of stuff that I work on.