http://news.yam.com/afp/life/200804/20080418051860.html
蝴蝶效應揚名 渾沌理論之父羅倫茲辭世
法新社╱林治平 2008-04-18 06:20
(法新社紐約十七日電)美國的麻省理工學院今天宣布,被尊為「混沌理論」之父的美國氣象學家羅倫茲昨天因癌症過世,享壽九十歲。
麻省理工學院表示,擔任該校教授的羅倫茲率先發現氣象系統數學模型中的混沌現象,也就是在像氣象之類的動態系統中,小小的變化就「可能引發巨大而且經常是意料外的結果」。
羅倫茲一九九一年曾獲頒京都基礎科學獎,評選委員會盛讚他提出的這套理論具有開創性,是「牛頓以來對人類對自然觀點造成最大改變的事情之一」。
這項研究讓羅倫茲提出所謂的「蝴蝶效應」,也就是看似微不足道的小小變化,例如昆蟲鼓動翅膀,也許會導致可能相當重大的後果。
這個名詞出自他一九七二年的一份學術報告,題目是:「可預測性:巴西一隻蝴蝶鼓動翅膀,會在德州引發一場龍捲風嗎?」
麻省理工學院發布的聲明說,羅倫茲早期這項研究工作「標誌一個新研究領域的開啟,影響的不只是數學的領域,而幾乎及於科學的各個學門,如生物學、物理學和社會學。」
聲明又說:「有些科學家聲稱,二十世紀有三項科學革命將為後人難忘,分別是相對論、量子力學和混沌理論。」
http://news.yahoo.com/s/afp/20080417/sc_afp/ussciencelorenz_080417165749
Edward Lorenz, father of chaos theory, dies
Thu Apr 17, 12:57 PM ET
NEW YORK (AFP) - Edward Lorenz, a meteorologist who became the father of the modern field of chaos theory, died Wednesday of cancer in Massachusetts aged 90, MIT announced Thursday.
A professor at the Massachusetts Institute of Technology (MIT), Lorenz was the first to identify chaotic behavior in the mathematical modeling of weather systems, in which small differences in a dynamic system, like the weather, "could trigger vast and often unsuspected results," the university said.
A committee that awarded him the 1991 Kyoto prize for basic sciences wrote that Lorenz's groundbreaking theory represented "one of the most dramatic changes in mankind's view of nature since Sir Isaac Newton."
Lorenz's research led him to develop what became known as the "butterfly effect," the idea that an infinitesimally small alteration -- like the flapping of an insect's wings -- can lead to potentially monumental consequences.
The term stemmed from his 1972 academic paper "Predictability: Does the Flap of a Butterfly's Wings in Brazil Set off a Tornado in Texas?"
MIT said Lorenz's early work "marked the beginning of a new field of study that impacted not just the field of mathematics but virtually every branch of science -- biological, physical and social."
"Some scientists have since asserted that the 20th century will be remembered for three scientific revolutions -- relativity, quantum mechanics and chaos," the statement said.
The original experiment that lead to Lorenz's groundbreaking theory was conducted in 1961, when he was using a numerical computer model to rerun a weather prediction.
When, as a shortcut on a number in the sequence, he entered the decimal .506 instead of entering the full .506127, the result was a completely different weather scenario.
Lorenz published his findings in a 1963 paper for the New York Academy of Sciences noting that "if the theory were correct, one flap of a seagull's wings could change the course of weather forever."
Later speeches and papers by Lorenz replaced the seagull with the more poetic butterfly.
Lorenz was working as a weather forecaster for the US Army Air Corps during World War II when he decided to pursue further study in meteorology.
But he wrote once that his interests in things mathematical and meteorological dated back much earlier, to his childhood.
"As a boy, I was always interested in doing things with numbers, and was also fascinated by changes in the weather," Lorenz once wrote in an autobiographical sketch.
His daughter told the New York Times that Lorenz was active in his field to the end of his life, in addition to also being vigorous and fit.
"He was out hiking two and one-half weeks ago, Cheryl Lorenz told the daily, "and he finished a paper a week ago with a colleague."
May the Force be with you