Learn The History Of Physics In 4 Minutes Aristotle was wrong. He claimed that heavier items fell faster than lighter items. Had he actually tested the theory, using a high-tech tool as sophisticated as a ladder, a ledge, or a cliff, he’d have immediately realized that it couldn’t possibly be true. Because Galileo did test the theory, and he found that balls of various mass fell at the exact same rate. Well, at least that’s what happened according to this fantastic animation directed by Åsa Lucande for BBC Science. [Hat tip: neatorama] Infographic of the Day: How the Global Food Market Starves the Poor To understand the complexities of the international food market--and how traders in Chicago can cause Africans to starve--you could get a ph.D. in economics, or read a 400-page report from the World Bank. Or you watch this superb nine minute video, directed by Denis van Waerebeke. Though ostensibly created for a science show in Paris for 12 year olds, it's actually probably waaaay over a kid's head. Just watch--it's excellent, and very well illustrated: The video begins with a basic question: How is it that the first world has an oversupply of food, while 1 in 7 in the world go malnourished? Basically, farmers in developing countries have eschewed growing local food crops in favor of growing things like cotton for international export. That can have disastrous effects. The solutions will involve everyone, the world over. Still hungry for more infographics videos? [Via Infosthetics]
Methane Made with Solar Power Will Power Audi Vehicles Gas maker: SolarFuel operates this 250-kilowatt demonstration plant that produces methane from carbon dioxide and hydrogen. Audi is building a plant that will use solar and wind power to make methane from water and carbon dioxide. The plant, which will use technology developed by Stuttgart, Germany-based SolarFuel, is scheduled to start operation later this year. It will produce enough methane to power 1,500 of Audi’s new natural-gas vehicles, which also go on sale this year. SolarFuel’s process uses excess renewable energy generated as a result of Germany’s push to reduce greenhouse-gas emissions. There’s now so much renewable energy in Germany that supply sometimes exceeds demand—such as when the wind is blowing late at night. SolarFuel says its approach may be a solution to one of the biggest challenges with renewable energy—its variability. To make the methane, SolarFuel combines two existing technologies. SolarFuel can’t compete directly with the wholesale price of natural gas.
Watch Free Documentaries Online | Documentary Heaven 3D solar panels can produce 20 times more energy than flat panels We see the trend in 3D technology everywhere: Movie theaters, home theaters, game consoles, 3D printers. But researchers at Massachusetts Institute of Technology recently discovered that creating a 3D-inspired solar panel not only help to keep up with the trends, it could draw in 20 times more energy than flat panel designs. Traditional solar panels lay flat on a surface or rooftop, facing the sun to collect energy. MIT researchers decided to change the shape of solar panels, conducting experiments with a cube, tall cube, and tower-shaped panels to see which design brought in more energy. Compared to flat panels, all three 3D panels created impressive results and outproduced traditional panels, with the accordion-style tower drawing in 20 times more power per square foot. The panels were tested during both cloudy and sunny conditions, and proved to perform consistently despite the weather changes.
Google’s New Search Tool to Use CIA and World Bank as Sources for ‘Facts’ Eric BlairActivist Post Google is making a big change to how it displays results in it’s dominant search engine. It is rolling out a new feature called the Knowledge Graph which breaks from the traditional practice of matching keywords with webpages. According to an article on Blog Tips about Google’s Knowledge Graph, immediate answers or “facts” from pre-selected sources like the CIA Factbook, Wikipedia, and the World Bank will be provided in search results along side the organic results: Instead of using the typical search strength of a particular answer, this new feature will draw “facts” from places like Wikipedia for historical information, CIA World Factbook for geopolitical answers, the World Bank for economic facts, Freebase for information about people and other predetermined sources. Sure, most would argue that Wikipedia does a pretty good job through its open-source format to nail down basic facts. Google also explains how it will collect data on you using the Knowledge Graph:
2 : La Physique Quantique : vers la recherche d'un absolu… Bien des physiciens croient que la meilleure façon de décrire le monde de l'atome demeure le modèle mathématique, et qu'à travers les équations nous pouvons entrevoir la façon complexe dont le monde microscopique est ordonné. Mais un orage souffle sur la physique du vingtième siècle, faisant trembler ses fondations et jetant la confusion sur la nature même de ses concepts les plus ultimes. Véritable révolution qui vient jeter un pavé dans la mare pourtant si tranquille de nos croyances acquises jusqu'alors, la physique quantique se révèle une théorie sans commune mesure avec tout ce qu'on croyait savoir au sujet du monde atomique. La théorie quantique décrit un monde étrange, où l'on découvre que la matière qui constitue tout notre univers, et qui semble pourtant bien localisée dans l'espace est en fait « étendue » quelque part.
La physique quantique (Philippe Grangier) - Université de tous les savoirs Transcription* de la 574e conférence de l'Université de tous les savoirs prononcée le 17 juin 2005 Par Philippe Grangier: « La physique quantique » La Physique Quantique est un sujet extrêmement vaste, et je n'aurai pas la prétention d'en présenter tous les aspects dans cet exposé. Je vais plutôt tenter d'illustrer quelques principes de base à travers des exemples simples, et aussi essayer de vous faire part de l'excitation actuelle qui existe dans ce domaine, à cause de résultats apparus récemment. Dans mes exemples, je parlerai beaucoup du photon, vous savez aussi que c'est le « Licht Quanten », le quantum de lumière qui a été introduit par Einstein en 1905 dans un article extrêmement célèbre qui fête cette année son centenaire. Je vous parlerai donc d'idées et de concepts, mais aussi d'expériences, et en particulier de celles que nous avons faites à l'Institut d'Optique à Orsay. Qu'est ce donc que la physique quantique ? Et en fait, ces petits nuages n'étaient pas si petits que cela.