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Comment 5 steps method (Score 2) 3

In order, I think you should : 1-Make sure you are good with basic vector and matrix math 2-Make sure you are good with basic newtonian physics (mechanics, gravity, etc) 3-(optional but very helpful) become familiar with coordinate changes (from cartesian to spherical and others like cylindrical) 4- Learn special relativity before general relativity... I specify it because sometimes it is not obvious that special relativity is a prerequisite for the general relativity because the names may be misleading (http://en.wikipedia.org/wiki/Special_relativity) 5- Learn about tensor (http://en.wikipedia.org/wiki/Tensor) Now you can start reading about general relativity

Submission + - Is Sugar Toxic? (nytimes.com)

a_hanso writes: From the NY Times: On May 26, 2009, Robert Lustig gave a lecture called “Sugar: The Bitter Truth,” which was posted on YouTube the following July. Since then, it has been viewed well over 800,000 times, gaining new viewers at a rate of about 50,000 per month, fairly remarkable numbers for a 90-minute discussion of the nuances of fructose biochemistry and human physiology.
Science

Submission + - Why Men Don't Have Spines on Their Penises (sciencemag.org) 4

sciencehabit writes: Most male mammals wield a penis covered with spines made of keratin, the same material that forms fingernails, to sweep out competitors' sperm and irritate a female into ovulating. Even chimpanzees, our closest relatives, have penile spines. So why don't men? A new study suggests that this feature disappeared due to a chunk of DNA that went missing after our evolutionary divergence from chimps. The researchers have identified another DNA deletion that may have contributed to humans' bigger brains.
Security

Submission + - Hackers find new way to cheat on Wall Street (infoworld.com)

GMGruman writes: The high-speed trading exchanges that conduct the business of buying and selling stocks and mutual funds are so fast that hackers can introduce delays of a few microseconds completely unnoticed by today's network monitoring technology — and manipulate prices in the process to reap millions of dollars to the detriment of everyone else, InfoWorld's Bill Snyder reports. This kind of activity creates new reason to distrust Wall Street and shows how the computer networks we all rely on for conducting business and moving information are ripe for undetectable hacking.
Science

Submission + - Hypersonic Radio Black-Out Problem Solved (technologyreview.com)

KentuckyFC writes: Russian physicists have come up with a new way to communicate with hypersonic vehicles surrounded by a sheath of plasma. Ordinarily, this plasma absorbs and reflects radio waves at communications frequencies leading to a few tense minutes during the re-entry of manned vehicles such as the shuttle. However, the problem is even more acute for military vehicles such as ballistic missiles and hypersonic planes. Radio black out prevents these vehicles from accessing GPS signals for navigation and does not allow them to be re-targeted or disarmed at the last minute. But a group of Russian physicists say they can get around this problem by turning the entire plasma sheath into a radio antenna. They point out that any incoming signal is both reflected and absorbed by the plasma. The reflected signal is lost but the absorbed energy sets up a resonating electric field at a certain depth within the plasma. In effect, this layer within the plasma acts like a radio antenna, receiving the signal. However, the signal cannot travel further through the plasma to the spacecraft. Their new idea is to zap this layer with radio waves generated from within the spacecraft. These waves will be both absorbed by the plasma and reflected back inside the spacecraft. However, the key point is that the reflected waves ought to be modulated by any changes in the electric field within the plasma. In other words, the reflected waves should carry a kind of imprint of the original external radio signal. That would allow the craft to receive external signals from GPs satellites or ground control. And the same process in reverse allows the spacecraft to broadcast signals too.
Idle

Submission + - Coffee spill diverts United Airlines flight (cnn.com) 1

PolygamousRanchKid writes: A United Airlines flight from Chicago to Frankfurt, Germany, was diverted to Toronto this week after the pilot dumped a cup of coffee on the plane's communication's equipment. The unwanted liquid triggered a series of emergency codes, including one for a hijacking, according to Transport Canada, the agency that regulates transportation in Canada.
Image

Survey Shows That Fox News Makes You Less Informed 1352

A survey of American voters by World Public Opinion shows that Fox News viewers are significantly more misinformed than consumers of news from other sources. One of the most interesting questions was about President Obama's birthplace. 63 percent of Fox viewers believe Obama was not born in the US (or that it is unclear). In 2003 a similar study about the Iraq war showed that Fox viewers were once again less knowledgeable on the subject than average. Let the flame war begin!
Earth

EPA Knowingly Allowed Pesticide That Kills Bees 410

hether writes "The mystery of the disappearing bees has been baffling scientists for years and now we get another big piece in the puzzle. From Fast Company: 'A number of theories have popped up as to why the North American honey bee population has declined — electromagnetic radiation, malnutrition, and climate change have all been pinpointed. Now a leaked EPA document reveals that the agency allowed the widespread use of a bee-toxic pesticide, despite warnings from EPA scientists.' Now environmentalists and bee keepers are calling for an immediate ban of the pesticide clothianidin, sold by Bayer Crop Science under the brand name Poncho."
Image

4chan Declares War On Snow 201

With all the recent hacktivism in the news, Anonymous has decided to take on a new and powerful enemy: snow. On Sunday the group announced that it will "do everything in its power to shut snow down by attacking the Weather Channel and North Face websites, boycotting outerwear, and voting for the sun as Time’s 2010 Person Of The Year." I'm sure there are a lot of people in Minneapolis right now that would wish them luck.
Government

Judge Declares Federal Healthcare Plan (Partly) Unconstitutional 1505

healeyb writes "In a surprise move, US District Judge Henry E. Hudson issued a ruling today that the universal healthcare law that was pushed through by the Obama administration is unconstitutional. Specifically, he invalidated the section of the law that requires all citizens to purchase healthcare insurance, arguing that it does not fall under the purview of Commerce Clause of the Constitution, as has been asserted by the government. The ruling represents the first major setback for President Barack Obama on an issue that will likely end up at the Supreme Court. Two other courts have shot down challenges to the law."
Image

Stunts, Idiocy, and Hero Hacks 208

snydeq writes "InfoWorld's Paul Venezia serves up six real-world tales of IT stunts and solutions that required a touch of inspired insanity to pull off, proving once again that knowing when to throw out the manual and do something borderline irresponsible is essential to day-to-day IT work. 'It could be server on the brink of shutting down all operations, a hard drive that won't power up vital data, or a disgruntled ex-employee who's hidden vital system passwords on the network. Just when all seems lost, it's time to get creative and don your IT daredevil cap, then fire up the oven, shove the end of a pencil into the motherboard, or route the whole city network through your laptop to get the job done,' Venezia writes."
Handhelds

Apple Removes Wi-Fi Finders From App Store 461

jasonbrown writes "Apple on Thursday began removing another category of apps from its iPhone App Store. This time, it's not porn, it's Wi-Fi. Apple removed several Wi-Fi apps commonly referred to as stumblers, or apps that seek out available Wi-Fi networks near your location. According to a story on Cult of Mac, apps removed by Apple include WiFi-Where, WiFiFoFum, and yFy Network Finder."

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