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Feynman Online

Feynman Online

Home Page Les conférences de Feynman en libre accès Richard Feynman jouant du bongo. Crédit : Tom Harvey Les conférences de Feynman en libre accès ! Merci Bill Gates ! - 2 Photos Imaginez Albert Einstein en train de découvrir la théorie de la relativité alors qu’il se détendait entre deux shows du Moulin Rouge, cette image résume en peu de mots l’un des esprits les plus libres et les plus puissants du vingtième siècle, Richard Feynman. Tout en passant sa thèse avec John Wheeler à Princeton, il commençait alors à développer une approche radicalement nouvelle de la théorie quantique des champs qui lui vaudra plus tard, en 1965, le prix Nobel de physique. Déjà différés par la Seconde guerre mondiale et l'implication de Feynman dans le projet Manhattan, les développements de ses idées, qui donneront naissance aux célèbres diagrammes de Feynman, mirent ensuite un certain temps à s’imposer à la fin des années 1940 et au début des années 1950. Joueur de bongo et amateur de danseuses Un enseignant hors pair A voir aussi sur Internet Sur le même sujet

How Many Stephen Colberts Are There? Todd Heisler/The New York Times Stephen Colbert dressing for a rehearsal of “The Colbert Report.” More Photos » Suburban Colbert comes out dressed in the other Colbert’s guise — dark two-button suit, tasteful Brooks Brothersy tie, rimless Rumsfeldian glasses — and answers questions from the audience for a few minutes. Lately, though, there has emerged a third Colbert. But those forays into public life were spoofs, more or less. “It’s bizarre,” remarked an admiring Jon Stewart, whose own program, “The Daily Show,” immediately precedes “The Colbert Report” on Comedy Central and is where the Colbert character got his start. In August, during the run-up to the Ames straw poll, some Iowans were baffled to turn on their TVs and see a commercial that featured shots of ruddy-cheeked farm families, an astronaut on the moon and an ear of hot buttered corn.

Indo-Aryan languages The Indo-Aryan or Indic languages are the dominant language family of the Indian subcontinent, spoken largely by Indo-Aryan people. They constitute a branch of the Indo-Iranian languages, itself a branch of the Indo-European language family. Indo-Aryan speakers form about one half of all Indo-European speakers (approx 1.5 of 3 billion) and more than half of Indo-European languages recognized by Ethnologue. The largest in terms of native speakers are Hindustani (Hindi-Urdu, about 240 million), Bengali (about 230 million), Punjabi (about 110 million),[2] Marathi (about 70 million), Gujarati (about 45 million), Bhojpuri (about 40 million), Oriya (about 30 million), Sindhi (about 20 million), Sinhala (about 16 million), Nepali (about 14 million), and Assamese (about 13 million) with a total number of native speakers of more than 900 million. History[edit] Indian subcontinent[edit] Old Indo-Aryan[edit] Middle Indo-Aryan (Prakrits)[edit] New Indo-Aryan[edit] Dialect continuum[edit] Dardic[edit]

AAVSO | American Association of Variable Star Observers BD : la vie trépidante de Richard Feynman, physicien génial et méconnu Le roman gra­phique "Feynman" retrace la vie du phy­si­cien de génie, pro­fes­seur à 24 ans et prix Nobel à 47 ans, grand séduc­teur, far­ceur et iconoclaste. L'histoire regorge de scien­ti­fiques géniaux et excen­triques. Le phy­si­cien anglais Henry Cavendish por­tait tou­jours les mêmes habits et se ser­vit pen­dant 30 ans du même cha­peau. Alan Turing, le père des ordi­na­teurs, fai­sait du vélo avec un masque à gaz et était obni­bulé par le des­sin animé Blanche Neige. A côté de cer­tains, Richard Feynman, prix Nobel de phy­sique en 1965, pour­rait sem­bler bien timoré. Le roman gra­phique Feynman de Jim Ottaviani, récem­ment tra­duit de l'anglais, relate la vie et l'oeuvre du génial phy­si­cien dans un registre tour à tour tou­chant, comique et péda­go­gique. Des dia­grammes de Feynman. Certaines de ses théo­ries lui sont venues en jon­glant avec des assiettes ou en jouant sur la plage, mais sa contri­bu­tion à la méca­nique quan­tique est indé­niable. Quentin Duverger

Stars gather to mark Adams' 60th 12 January 2012Last updated at 15:02 Douglas Adams passed away in 2001 The 60th birthday of the late writer Douglas Adams, creator of The Hitchhiker's Guide To The Galaxy, is to be marked with a special show. Comedians, writers and scientists are coming together for the event at London's Hammersmith Apollo in March. Clive Anderson, Stephen Fry, Michael Palin and Professor Brian Cox are set to participate in the one-off event. Tickets for the show will go towards the Save the Rhino charity, which Adams supported. According to the website, which has been set up especially for the event, there will be a "special premiere performance" of Douglas material. As part of the line up, Anderson will talk to Terry Jones and Michael Palin about Douglas's comedy legacy and his influences, including Monty Python. Stephen Fry and zoologist and wildlife photographer Mark Carwardine have recorded a special introduction about Douglas' passion for conservation. Adams died in 2001 aged 49 following a heart attack.

The physics of cricket 2. The Sweet Spot Every batter knows that there is a special spot on a bat where the shot feels best. It sometimes feels so good that there is almost no sensation at all that the bat hit the ball. It's the same with a baseball bat or a tennis racquet or a golf club, so there is nothing special in this respect about cricket bats. Two special points on a bat are good candidates for the sweet spot. An impact near the tip of a bat will generate bad vibrations and it will also cause the handle to jerk forwards (towards the bowler), pulling your hand and arm with it. Almost every type of ball used in a sporting event must bounce according to the rules of the game. There is no such official rule for a cricket ball. Suppose that a cricket ball is bowled at 100 km/hr, the batter swings the bat at 60 km/hr, and hits the ball straight back over the bowler's head. The effectiveness or the power of any given bat can be tested without swinging the bat at all. Air plays an important role in cricket.

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