Eu não me lembro direito, mas me parece que o tema do meu projeto de pós-doc no grupo do Fontanari no IFSC era sobre sistemas críticos auto-organizados acoplados. Ou será que foi no pós-doc com o Salinas? Não lembro e estou com preguiça de consultar meu currículo Lattes...
Ou seja, se eu tenho dois sistemas críticos auto-organizados (o que quer que isso signifique) e eu os acoplo ainda que de maneira fraca, de que modo as avalanches em um deles podem se propagar para o outro? Ainda de outro modo, será que sistemas críticos, quando acoplados, já não são separáveis (no sentido de teoria de perturbação) e se tornam um só sistema devido à ausência de escalas espaço-temporais típicas, flutuações críticas etc e tal?
Se você não está entendendo esse monte de jargão, não faz mal, eu também não sei o que seja Fenomenologia (em Filosofia) e levei anos para entender (acho) o que seja Dialética, embora sejam termos que todo mundo que escreve no Caderno Mais da Folha usa e os leitores não reclamam.
Em todo caso, consulte a Wikipédia no tema Self-organized Criticality, veja este artigo na Revista Brasileira de Ensino de Física ou, melhor ainda, leia o livro do Mark Buchanan. Agora, uma referência indispensável para os pesquisadores da área são os trabalhos do Ronald Dickman da Universidade Federal de Minas Gerais e colaboradores, que integram os modelos com SOC (self-organized criticality) ao resto da Física Estatística usual de transições de fase fora do equilíbrio.
The Day the Pixels Froze: When a Digital World Was Stopped by a Natural Disaster
By SETH MYDANS do New York Times
Published: December 28, 2006
BANGKOK, Dec. 27 — It was a natural disaster for the digital age that radiated through much of Asia and beyond after an undersea earthquake late Tuesday off the coast of Taiwan.
People awoke Wednesday to find themselves without e-mail or the Internet and, in some cases, without telephone connections, cut off from the rest of the world. The earthquake ruptured undersea cables that are part of a communications fabric that circles the globe. Coming on the second anniversary of the Asian tsunami that killed 230,000 people, it was a reminder of the world’s increasing dependence on communications technology. Financial companies and technology services suffered most directly. Operations from travel agencies to newspapers to schools struggled to maintain their routines.
“You don’t realize until you miss it how much you rely heavily on technology,” said Andrew Clarke, a sales trader in Hong Kong. “Stuff you took for granted has been taken away and you realize, ‘Ah, back to the old way, using mobiles.’ ”In this time of rapid change, it is easy to forget how quickly innovations have become necessities, including cellphones, the Internet, e-mail and instant messaging on both the computer and telephone. “I’m completely dependent on the Internet,” said Robert Halliday, an American writer based in Bangkok. “If the Internet goes down for half a day, people can just stay in bed in terms of getting any work done.” On Wednesday, he was frustrated in trying to get information for a review he was writing of a Romanian DVD. It takes a moment to realize what a task that would have been just a few years ago. The words “instant” seems to have lost some of its edge. It has become the norm, and anything else seems agonizingly slow.The word “global” has shrunk to the size of a computer screen. When Mr. Halliday’s mother, who is in her 80s, wants to reach him, she taps an instant message into her telephone from the United States. “All of a sudden,” he said, “there’s a message on the phone, ‘Oh, you should be here, the azaleas are out.’ ” Without e-mail, Ken Streutker, a Dutch-Canadian actor and producer in Thailand, had no way to arrange a meeting with a friend who was arriving at the airport in Bangkok. “Now I’ll have to stand there at the airport with the traditional handwritten sign and hope that someone notices,” he said.Many enterprises found themselves paralyzed without the Internet. In Beijing, Wang Yifei, an independent television producer, sent instant telephone messages when her Internet connection was down. “I had a horrible day,” she said. “I’ve been complaining about this all day. This high-tech world of ours. It didn’t happen in the old days. In the end I can’t do anything.” In Manila, Abe Olandres, who owns and runs a Web-hosting company, just about gave up. He said he planned to try a Wi-Fi hot spot in a coffee shop after struggling at the office all day. “This is killing me,” he said. For his customers, it may have been worse. When their service went down, they tried to reach his help desk, but it was down, too.Niall Phelan, the creative director of APV, a media production company inHong Kong, said he usually received about 300 e-mail messages a day. On Wednesday, he said, he got none. Without e-mail, he was back to the old-fashioned way of communicating, by telephone, which greatly multiplied his work. “Usually, one e-mail is cc’d to lots of people,” he said. “But, with calling, you have to contact all six involved people individually.” With their work day disrupted, he said, “Most people I spoke to in Hong Kong today are just twiddling their thumbs.” He made the best of it. “What I didtoday was eight hours of filing,” he joked. “I had a year’s worth of paperwork. If the Internet is still down tomorrow, maybe I will finish it.”Even without the help of technology, work seems to have its own momentum. Lucy Fennell, regional business development director at APV, stayed late in the office despite the enforced slowdown. “What I did do today was, well,” shelaughed, “I’ve filled in my diary for all of next year, you know, with friends’ birthdays and things. I guess you have to do that.” Carolyn Mison-Smith, director of a language center in Singapore, found in the communications crash a concrete demonstration of the interconnectedness of the world. “Cables all over the seabed,” she said. “I don’t know if your average dude appreciates thatfact. “Who puts them there and how long does it take and how many kilometers is it?” she said. “If they’ve got cords going all over the seabed, I think that’s fascinating. Who designs it all, who’s the engineer that designs it and who are the laborers who go down and do that?”
Foto: Per Bak (8 de Dezembro de 1947- 16 de Outubro de 2003). Vários obituários interessantes feitos por colegas e revistas científicas estão aqui.