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Proving 0.999... Is Equal To 1 1260

eldavojohn writes "Some of the juiciest parts of mathematics are the really simple statements that cause one to immediately pause and exclaim 'that can't be right!' But a recent 28 page paper in The Montana Mathematics Enthusiast (PDF) spends a great deal of time fielding questions by researchers who have explored this in depth and this seemingly impossibility is further explored in a brief history by Dev Gualtieri who presents the digit manipulation proof: Let a = 0.999... then we can multiply both sides by ten yielding 10a = 9.999... then subtracting a (which is 0.999...) from both sides we get 10a — a = 9.999... — 0.999... which reduces to 9a = 9 and thus a = 1. Mathematicians as far back as Euler have used various means to prove 0.999... = 1."

Facebook Introduces One-Time Passwords 215

angry tapir writes "Worried about logging into Facebook from a strange computer? There's now a way to get into the popular social network without entering your regular Facebook password. It's called a temporary password. To use it, users must list their mobile phone numbers with their Facebook accounts. They can then text a number from their phones and Facebook sends back a temporary password that is good for 20 minutes. The service will be available worldwide in the next few weeks."

Ubuntu 10.10, Maverick Meerkat, Now Available 473

teeks99 writes "The latest version of Ubuntu — 10.10, called Maverick Meerkat — has been released. This release contains new improvements, like an update to the Ubuntu One online service (with music streaming), Shotwell instead of F-Spot, the new Unity interface (for netbooks), and an upgrade to just about every piece of existing software. The announcement e-mail has more details."

The Encryption Pioneer Who Was Written Out of History 238

nk497 writes "Clifford Cocks is one of three British men who developed an encryption system while working for the UK government in the early 1970s, but was forced to keep the innovation quiet for national security reasons. Just a few years later, their Public Encryption Key was developed separately by US researchers at Stanford and MIT, and eventually evolved into the RSA encryption algorithm, which now secures billions of transactions on the internet every day. 'The first I knew about [the US discovery] was when I read about it in Scientific American. I opened it one lunchtime and saw a description and thought, "Ah, that's what we did,"' he said. 'You don't go into the business to get external credit and recognition — quite the opposite. Quite honestly, the main reaction was one of complete surprise that this had actually been discovered outside.' The UK trio have now won recognition for their accomplishment in the form of the Milestone Award from the Institute of Electrical and Electronics Engineers."

Submission + - Google responds to Oracle's Java lawsuit (

calmond writes: The International Business Times has an interesting article up on Google's response to Oracle's Java lawsuit regarding the Dalvik virtual machine used in Android. Google claimed that it has an implied license to use the patents in question, and iterated that Oracle and Sun smack of hypocrisy as they fail to comply with the basic tenets of open-source.

Submission + - free temporary email address that lasts for 4 hrs (

An anonymous reader writes: no need to click even a single button to use this temporary email site as randomly generated email address gets automatically copied to clipboard. no need to refresh page even.

Submission + - Solar power coming to the White House (

crimeandpunishment writes: The White House is going greener. Solar panels will be installed by next spring, and will heat water for the first family and provide some electricity. President Obama, who has been a big supporter of renewable energy, has been under pressure to lead by example. It's still unclear how much the project will cost and how much fossil fuel-based electricity it will replace.

Submission + - Smashtalk Delivers Text Messaging 2.0 (

mryanaz writes: Smashtalk is text messaging software that is designed to replace the existing text messaging software found in today’s smartphones and feature phones. Smashtalk text messages carry the complete list of recipients along with each text message thereby allowing the recipient to have a “Reply All” function not available with today’s text messaging.

Smashtalk text messages are fully backward compatible with existing text messaging software in that a non-Smashtalk user receiving a Smashtalk text message will see a normal text message without the “CC:” list that a Smashtalk user would see. The Smashtalk user can reply to any or all of the original recipients while the normal text messaging user can only reply to the sender or others they may manually add to the sending list.

The net result is text-message based conversations which today, are not possible.

Submission + - PandaBoard ARM dev kit launches (

Stoobalou writes: The popular open-source ARM development platform BeagleBoard has been updated with a shiny new OMAP4 version — the dual-core 1GHz PandaBoard.

The PandaBoard is designed to be a refresh to the BeagleBoard platform: a teeny-tiny little fully-functional computer based around — in the case of the PandaBoard — TI's OMAP4430 ARM Cortex-A9 MPcore processor.

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