• In metaphysics, extension is the property of taking up space; see Extension (metaphysics).
• In semantics (with applications to both philosophy and mathematics), extension is the set of things to which a property applies; see extension (semantics).
• In dentistry, enamel extension.
• In general semantics, extension is a process that, as in this mathematical example, starts with unique individuals, and gives them unique names, e.g., I, II, III, etc., or 1, 2, 3, etc. The next step if needed generalizes or passes beyond extension to infinite-valued higher-order abstractions like 'numbers', and so on. The passing from lower-order abstractions (presented extensionally) to higher orders, e.g., from '1, 2, 3, etc.,' to 'numbers,' is said to follow the 'natural order of evaluation,' so that when one talks about order, extension is implied, and when one talks about extension, order is implied. An example of reversed order is when a particular higher-order abstraction such as race, e.g., 'white', 'black' etc., is projected onto the individuals comprising it. The individuals (each uniquely different by extension, no matter what is being discussed) comprise the 'race' (which exists only on higher-orders), not the other way around. This usage derives from extension (semantics). See extensional devices.
• In mathematics, an extension of some structure is another structure which contains the original structure.
  • For the extension of a group or algebra, see group extension.
  • For the extension of a predicate, see extension (predicate logic).
  • For the extension of a field, see field extension.
  • For the extension of a bounded linear operator, see continuous linear extension.
  • In model theory, a model B is an extension of a model A (and A is a submodel of B) if and only if the universe of A is a subset of the universe of B and the interpretations of the nonlogical symbols of A are the restrictions of the interpretations of the same symbols of B to the universe of A.
• In anatomy, extension is one of the movements of a joint such as the knee.
• Extension (geology)
• Extension (telephone)
• In computing:
  • For the programming concept, see extension (computing).
  • For the Apple Mac OS implementation of operating system extensions, see Extension. For problems with same, see extension conflict.
  • For the last part of a filename, see filename extension.
  • For the addons for the Firefox Web Browser, see Extension (Mozilla)
• In community development, extension involves the building of community capacity by outsiders. Examples are health or agricultural extension. See extension agency.
• Electricity and electronics: Extension cable.
• Hair extensions are strands of human hair placed onto a persons hair in order to elongate or thicken existing hair.
• In education, an extension course, program, or school is continuing education.
• Extension, BC is a small former coal-mining village near Nanaimo, BC, Canada.
• In cheerleading, an "extension" is a stunt comprising of a flyer being held in the air by the bases' fully extended arms.
• In music, an extension is a set of notes that fit outside the standard range.

More on [ Extension ]

eWeek - RSS Feeds

Passports: Another Bad Use of Self-Signed Certificates
Sat, 04 Oct 2008 15:37:28 -0400
The offline nature of the passport data makes it impossible to validate in any meaningful way. This weakness made it easy for hackers to device systems for cloning and modifying passport RFID chips. - I'm surprised it took this long: Hackers have released the specs and tools to clone and modify the RFID chips in US passports. 2 years ago when the plan to issue them was first widely discussed I asked what purpose they served and pointed out obvious problems with them. As far as I can tell, e-passp...
Craig Newmark Makes New List for Congress
Fri, 03 Oct 2008 17:23:00 -0400
Craigslist's founder is stumping the country for a more responsive and transparent government that puts everything the government does online. He's not just talking either, putting his support behind a variety of sites that track legislation, members of Congress, their staff, federal spending and lobbyists. If only the U.S. Senate would cooperate. - WASHINGTON Craig Newmark is getting political, even though the Craigslist founder readily admits, quot;Most people don't want to be bothered by politics, including myself. quot; Nevertheless, Newmark is banging the drum for Barack Obama and urging young voters to register to vote. quot;We nee...
Treo Pro Looks Good, but Needs Improving
Fri, 03 Oct 2008 16:39:10 -0400
The Treo Pro from Palm is bringing a sleek new look to the smart phone for businesses users. However, the erratic 3G performance and battery life issues in the Palm Treo Pro need to be resolved. - With the new Treo Pro, Palm for once is bringing the sexy to business users, delivering a sleek, appealing device ready for business use. Unfortunately, the Treo Pros erratic 3G performance quickly depletes the battery under certain circumstances, making it difficult to recommend the device until...
IBM Lotus Symphony 1.1 in Need of an Update
Fri, 03 Oct 2008 16:30:45 -0400
IBM Lotus Symphony 1.1 offers users a clean and attractive user interface,but it's based on a 4-year-old version of OpenOffice.org. Lotus Symphony 1.1 lacks a lot of the features and support offered in such competitive products as Microsoft Office. - Lotus Symphony 1.1 is a freely available office productivity suite from IBM that brings together a trio of word processor, spreadsheet and presentation applications under a clean and well-implemented user interface. IBM built Symphony's UI atop the Eclipse IDE and the company's own Lotus Exped...
KDE Ships 'Codename'
Fri, 03 Oct 2008 16:27:16 -0400
The KDE community has released KDE 4.1.2, which is code-named Codename. KDE 4.1.2 is a monthly update to the KDE 4.1 series of the popular free Linux desktop environment. The community will continue with monthly updates, ultimately reaching the next major release, KDE 4.2, in January 2009. - The KDE community has announced quot;Codename, quot; which is actually the code name for KDE 4.1.2, the latest version of the popular free desktop for Linux. Officials at KDE, the nonprofit organization that represents the KDE Project, said KDE 4.1.2 is a bug fix and maintenance update for the ...
First Impressions of Google Android
Fri, 03 Oct 2008 16:07:44 -0400
Google's Android mobile operating system holds a lot of promise for developers. Key features in Android include the ability for all applications to work together and to run in parallel. - The picture on the emulator Web site certainly looks intriguing. That was my first impression of Android, Googles new operating system for handheld devices. The image I saw reminded me of Windows Vista, with a clock gadget and some folder icons on it. To give Android a test run, I installed the ...

The Seattle Times: Business & Technology

Simple money moves can help family with special needs
Sat, 04 Oct 2008 18:04:15 -0700
When it comes to financial matters, Chad and Amy Patterson tend to play it safe. Before starting a family, the Lake Stevens couple made...
Small stuff suddenly seems big
Sat, 04 Oct 2008 17:44:48 -0700
In times of bad markets, investors don't just worry about the big things, they sweat the small stuff. For proof, consider this question...
Lawsuit raises new questions about demise of subprime lender MILA
Sat, 04 Oct 2008 18:08:35 -0700
Until WaMu failed, the biggest local business brought down by the mortgage crisis was subprime lender MILA, which closed abruptly in April...

NYT > Technology

Digital Domain: Can’t Open Your E-Mailbox? Good Luck
Sat, 04 Oct 2008 18:44:03 -0000
What would you do if you logged onto your e-mail and received an unfamiliar message: “User name and password do not match”?
Google and Yahoo Delay Ad Deal for Antitrust Review
Sat, 04 Oct 2008 03:42:17 -0000
The delay of the search advertising partnership would give the Justice Department more time to investigate its antitrust implications.
Credit Crisis Spreads a Pall Over Silicon Valley
Fri, 03 Oct 2008 21:34:35 -0000
Entrepreneurs and investors believe the question is when, not if, the country’s cradle of innovation will be hurt.

CNN.com - Technology

'Space elevator' could take humans into orbit
Fri, 03 Oct 2008 18:28:38 -0400
A new space race is officially underway, and this one should have the sci-fi geeks salivating. The project is a "space elevator," and some experts now believe the concept is well within the bounds of possibility -- maybe even within our lifetimes.
MIT celebrates 50 years of 'Smoot'
Sat, 04 Oct 2008 18:39:49 -0400
Read full story for latest details.
Chertoff seeks cyber counterattack system
Sat, 04 Oct 2008 11:00:51 -0400
First, there was "Einstein," the federal government's effort to protect itself from cyber attacks by limiting the number of portals to government computer systems and searching for signs of cyber tampering.

NPR Topics: Technology

New Solar Cell Easy As Pizza To Make
Sat, 04 Oct 2008 12:16:00 -0400
The iJET is a new type of solar cell that's cheap and easy to make, requiring not much more than a pizza oven, some nail polish remover, and a common inkjet printer. Australian scientist Nicole Kuepper describes her invention.
SpaceX Celebrates First Successful Rocket Launch
Fri, 03 Oct 2008 13:53:00 -0400
SpaceX's flagship Falcon1 rocket has successfully launched from an island in the central Pacific, becoming the first privately-developed rocket to orbit the planet. NASA has already contracted SpaceX to begin private space flight missions to the International Space Station beginning in 2010.
Northeast States Trade Carbon Emission Credits
Fri, 03 Oct 2008 13:46:00 -0400
A consortium of Northeast states has completed the first cap-and-trade greenhouse gas auction in the U.S. Under cap-and-trade, limits are set on emissions. Companies that do not use up their quota of emissions are able to sell their excess emission capacity to other companies.

BBC News | Technology | UK Edition

China 'spying on Skype messages'
Fri, 03 Oct 2008 01:38:32 -0000
Chinese officials are censoring messages sent through the internet service Skype, Canadian researchers say.
Obama uses iPhone to win support
Fri, 03 Oct 2008 00:30:12 -0000
US Democratic candidate Barack Obama launches an application that could turn the iPhone into a political recruiting tool.
Music stars unite to seek control
Fri, 03 Oct 2008 23:30:43 -0000
Acts including Robbie Williams and Radiohead join a coalition to try to gain ownership and control of their music from record labels.

Reuters Video: Technology

Solar clothes
Fri, 03 Oct 2008 15:30:01 -0400
Oct. 3 - Argentine designer looks to the future by creating solar-powered clothing.
Ring ring, bling bling
Fri, 03 Oct 2008 14:21:52 -0400
Oct. 3 - Ring ring, bling bling; NIntendo's latest player, 3D reality, and a hybrid motorbike.
Nokia aims to take bite out of Apple
Fri, 03 Oct 2008 10:54:05 -0400
Oct 3 - The world's largest mobile handset maker is launching a 'free' music package and its first touch phone in a challenge to Apple's dominance of the digital music market.

AP Top Technology News At 4:35 p.m. EDT

Ex-McAfee executive clear of illegal option dating
By PAUL ELIAS Fri, 03 Oct 2008 22:22:15 -0000
SAN FRANCISCO (AP) -- A jury on Friday acquitted the former top lawyer at computer-security software maker McAfee Inc. of illegally tampering with his stock option grants to boost his pay package....
RIM CEO: AT&T still testing delayed BlackBerry
By PETER SVENSSON Fri, 03 Oct 2008 21:18:15 -0000
NEW YORK (AP) -- A delayed top-of-the-line BlackBerry phone from Research in Motion Ltd. is still undergoing testing by AT&T Inc., and RIM's co-CEO implied that the carrier wants to avoid the chorus of complaints about performance that greeted the new iPhone this summer....
Labor report indicates squeeze on tech sector
By BARBARA ORTUTAY Fri, 03 Oct 2008 18:00:34 -0000
NEW YORK (AP) -- The economic slowdown has started to squeeze the technology sector. So far this has not led to wide-scale job cuts, but a slowing demand for computers and other electronics may already be weighing on some payrolls....

CNET News.com

Apple cures the common cold and other stuff
Sun, 05 Oct 2008 07:39:00 -0700
Rumors of a "revolutionary" manufacturing process make the rounds - and this time the hype is off the charts.
Report: Palin, Obama lead in election-related spam
Sat, 04 Oct 2008 13:43:00 -0700
The spam study doesn't mean much in terms of who actually wins the election, but it does show spammers are staying on top of what names are hot among Net users.
Who's to blame for spreading phony Jobs story?
Sat, 04 Oct 2008 11:08:00 -0700
Silicon Alley Insider and CNN are at center of controversy surrounding false report that Apple CEO Steve Jobs suffered a heart attack. Citizen journalism may not be solely to blame.

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