Knot theory A knot diagram of the trefoil knot Knots can be described in various ways. Given a method of description, however, there may be more than one description that represents the same knot. For example, a common method of describing a knot is a planar diagram called a knot diagram. Any given knot can be drawn in many different ways using a knot diagram.
TED talks are lying to you The writer had a problem. Books he read and people he knew had been warning him that the nation and maybe mankind itself had wandered into a sort of creativity doldrums. Economic growth was slackening. The Internet revolution was less awesome than we had anticipated, and the forward march of innovation, once a cultural constant, had slowed to a crawl. Digital Drawing Board Creates Objects in Stunning 3D Detail ETOS, or Electronical Tool for Object Sketching, is a tool for designers and architects that lets them see their creations in three dimensions without the need for 3D glasses. The tool uses the familiar shape of a pen and the intuitive function of a touch interface to bring sketches into the real world. The drawing board takes the form of a tablet computer with a built-in stand formed from its folded cover. It displays objects in 3D using lenticular lens technology and motion tracking, which also allows users to move the shapes around with their hands.
The 20 most-watched TED Talks to date TEDTalks The 20 most-watched TEDTalks (so far) Today, on the fifth birthday of TEDTalks video, we’re releasing a new list of the 20 most-watched TEDTalks over the past five years — as watched on all the platforms we track: TED.com, YouTube, iTunes, embed and download, Hulu and more … What a great, mixed-up group this is! Talks about education and creativity, sex […] Eat, Drink and Live Forever: Immortality is 20 Years Away It seems that we’ve been edging toward becoming a race of cyborgs for a number of years. Medical advances like replacement limbs and joints, cochlear implants, and artificial organs are already being used. Improving medical technology and our understanding of anatomy will continue to drive the human race toward immortality, according to scientist Ray Kurzweil. He believes that within 20 years, there will be no need for humans to face death at all.
Ads Worth Spreading Ads honored through Ads Worth Spreading can be as long as it takes to communicate the idea powerfully, up to five minutes, whether that’s through state-of-the-art animation, lush imagery or an individual talking directly to the camera. What matters is the “a-ha” moment -- the central idea. The thing that makes consumers connect to the idea in the same way that TED speakers connect with their audience. Ads Worth Spreading began as a clarion call to the global advertising community in 2011, asking for ads that inspired and engaged audiences. TED received nearly 1,000 entries and picked 10 outstanding examples.
Appendicitis? Human Appendix Maybe Not Useless After All For a long time, we’ve believed that the human appendix was more or less good for nothing. Darwin postulated that the appendix was a remnant of evolution that was no longer needed. But for the first time, researchers are actually taking a close look at the appendix and its function. And they’ve come to believe that it is, after all, good for something: it may help to restock the stomach with good bacteria after an illness, like a bout of diarrhea.
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