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Comment Re:If there was a Bad at Math Map... (Score 1) 1163

I'm not sure what it is about the US that makes it impossible to have more than 2 parties, but first past the post isn't it.

For the presidency, the US has a double first-past-the-post system for a single seat. Electing a minor party requires winning a majority of a pluralities: a plurality in enough states to get an electoral college majority. That's a very tough task, somewhat harder than trying to elect a Green party candidate nationwide if all Canadians voted for a single "Prime Minister Seat."

Parliamentary systems like Canada also do more to encourage minority parties at the per-seat level, for a few reasons:

  • In a minority government, like Canada has seen for much of the last decade, minority parties like the NDP and BQ really do have legitimate power to shape the national agenda.
  • In a majority government, nobody expects the opposition parties -- any of them -- to have much if any influence on the agenda, so to first order it doesn't matter what party you vote for provided it's not for the nationwide winner. Strategic voting does affect this, but it also cuts both ways if a minority party puts out a strong, local showing.
  • Party discipline is also much stronger in Canada than the United States, so the parties occupy correspondingly smaller ideological grounds. In the States, a Republican in New York City is not necessarily the same as a Republican in Alabama, and a southern Democrat will still tend to be more conservative than a Northern counterpart -- and this really does influence legislation, to both good and ill. The upshot is that third parties are less likely to get a consistent regional base in the States, since the local duopoloy will incorporate the regional idiosyncrasy.

Submission + - No Patent Infringement Found in Oracle vs. Google (cnet.com)

sl4shd0rk writes: Today, the jury in the Oracle vs. Google trial found Google innocent on infringement claims. The jury deliberated about 30 minutes to reach the verdict bringing an end to the second phase of the trial, and a beginning to the damage phase which may be very little of what Oracle orginally asked for. Still no word on API copyright issues. Judge Alsup will be ruling on that in the near future and certainly have an impact on the dev community.

Comment A lay perspective (Score 2) 147

I am a scientist, but not an E&M specialist. Take this with a grain of salt.

I've read through the New Journal of Physics article. The ``radio vorticity'' means that the phase of the signal goes through a 180 flip across the beam centre, and the zero-point of this phase shift rotates as you move along the beam. The receiving antennas in the experiment were a pair of yagis, used to create a radio interferometer. The math and experimental results behind this appaer sound, but there are a few limitations:

  • This is a highly directional effect. Not only would multipath interference destroy the crap out of this signal, but they also needed pairs of antennas on opposite sides of the beam centre to discriminate between mode-0 and mode-1 rotations. Directionally-wide beams will have more interference, and building the interferometer will be more difficult with less than a 180 separation.
  • The transmitting antenna was very specialized. The transmitter itself not so much, but the antenna was a parabolic antenna ``mechanically modified'' -- they sliced through the top of it to turn the atenna into one loop of a parabolic spiral. If you have access to the article online, take a look at the picture, it's kind of neat.
  • ``In principle an infinite number of channels'' my ass. They're building an interferometer, so they need at least one antenna per mode they wish to discriminate between, and when they used antenna-separation to do the phase filtering for them they saw some significant interference form secondary lobes for intervals where the match wasn't perfect. This was okay for the two-channel experiment (mode 0 and 1), but the receiving antenna design would really start messing with higher channels, where those secondary lobes start seriously interfering themselves.
  • As written, the receiving antenna design is highly sensitive. The phase cancellation used required some pretty precise antenna positioning, since they needed a displacement of one half-wavelength in the beam direction for proper interference (to discriminate the mode 1 angular momentum). Trying this in a production environment is going to be pretty tricky -- perhaps they could get somewhere with electronic phase delay.

So for controlled channels -- perhaps even microwave links -- I'm optimistic about engineers being able to build something useful out of this. But the basic math isn't going to generalize to omnidirectional links, and it certainly isn't going to deal well with strong multipath interference. Simply being able to discriminate between modes requires straddling the beam centre, so this absolutely isn't going to work for general consumption.

Also, I don't think that practical antenna design will ever allow more than three or four channels of angular momentum outside of a lab setting. Even that may potentially be a huge win for fixed microwave links, though.

Comment Re:Theoretical limits? (Score 3, Informative) 105

Without reversible computing, there indeed is a fundamental limit to how much energy a computation takes. In short, "erasing" one bit of data adds entropy to a system, so it must dissipate kT ln 2 energy to heat. This is an extremely odd intersection between the information theoretic notion of entropy and the physical notion of entropy.

Since the energy is only required when information is erased, reversible computing can get around this requirement. Aside from basic physics-level problems with building these logic gates, the problem with reversible computing is that it effectively requires keeping each intermediate result. Still, once we get down to anywhere close to the kT ln 2 physical constraint, reversible logic is going to look very attractive.

Comment Re:Did ayone read the paper? (Score 5, Informative) 283

Yes, I did read the paper. (Disclaimer: I have a PhD, but not in graph theory. Your results may vary.)

In short, the paper repeats analysis and numerical simulations of a simplified 'agreement model'. People are abstracted as nodes on a graph, communication happens between them, and consensus is reached. If a graph is initialized randomly, with nodes 'believing' either A or B, eventually (in log(N) time) the graph reaches consensus with every node 'believing' A xor B.

This paper adds a twist; some fraction of nodes are 'committed' to A, and cannot ever be convinced of B. To quote the paper:

Here, we study the evolution of opinions in the binary agreement model starting from an initial state where all agents adopt a given opinion B, except for a finite fraction p of the total number of agents who are committed agents and have state A. Committed agents, introduced previously in [23], are defined as nodes that can influence other nodes to alter their state through the usual prescribed rules, but which themselves are immune to influence.

Now, if even one node cannot be convinced of B, then no consensus can be reached -- but it doesn't really matter. If the fraction is really small, then you can more or less ignore them.

The interesting part about that paper is their threshold effect -- once p gets to be over 10%, not only does A eventually win, but it does so -quickly-.

The applications to politics still hold, but not on the big, obvious issues. Those issues, like taxes and abortion and health care and anything else that really makes the news, have committed believers on both sides -- they're outside the scope of study. Where this research becomes really interesting is in quieter, uncontroversial issues -- like regulation details, or climage change before Al Gore. There, this research suggests that the influence of sockpuppetry and lobbying is nonlinear -- beyond a critical point, the lobbyists completely win.

Of course, caveats about "the real world isn't an abstract graph" apply.

Submission + - Google Chrome tag to abandon H.264

Art3x writes: As you know, HTML 5 introduced the <video> tag, so you don't have to use Flash, QuickTime, etc. It can even enclose several versions of the same video (H.264, WebM, Ogg, etc.) for different computers or browsers. Well, for Google Chrome in a couple months, you will have to provide it something other than H.264, because it is dropping support for H.246. 'Though H.264 plays an important role in video, as our goal is to enable open innovation, support for the codec will be removed and our resources directed towards completely open codec technologies,' wrote Mike Jazayeri, Product Manager.

Submission + - MySpace lays off 47% of employees (cnn.com)

tgtanman writes: CNN reports that Myspace has announced that they have laid off 500 employees, 47% of their total staff. From the article, "MySpace's management kept most of the site's developers but gutted nearly every other job role, according to a staffer who survived the cuts ... 'Today's tough but necessary changes were taken in order to provide the company with a clear path for sustained growth and profitability,' CEO Mike Jones said in a written statement.'These changes were purely driven by issues related to our legacy business, and in no way reflect the performance of the new product.' "

Submission + - Twitter Users Have Regional Accents Says CMU Study (itnews.com.au)

aesoteric writes: Twitter users tweet messages with regional dialects, using "suttin" for "something" if they are New Yorkers and "sumthin" if they are not, according to a Carnegie Mellon study. The study looked at 380,000 tweets by 9,500 users who wrote at least 20 messages via cell phone over a week in March 2010. The differences in regional expression reportedly allowed researchers to predict the location of a user in the United States within about 300 miles. The full research paper can be downloaded as a PDF.

Submission + - Facebook's HipHop also a PHP webserver (developer.com)

darthcamaro writes: As expected, Facebook today announced a new runtime for PHP — called HipHop. What wasn't expected were a few key revelations disclosed today by Facebook developer David Recordan. As it turns out Facebook has been running HipHop for months and it now power 90 percent of their servers — it's not a skunkworks project it's a Live production technology. It's also not just a runtime, it's also a new webserver.

"In general, Apache is a great Web server, but when we were looking at how we get the next half percent or percent of performance, we didn't need all the features that Apache offers," Recordon said. He added, however, that he hopes an open source project will one day emerge around making HipHop work with Apache Web servers.


Submission + - First NASA Crew Development Contracts Announced

FleaPlus writes: NASA's C3PO program has announced the first year's winners of a $50M contract competition for developing commercial spaceflight systems; their initially-planned $150M in funding was diverted by Congress towards the soon-to-be-cancelled Constellation project. The contracts are for $20M to Sierra Nevada for their in-progress Dream Chaser reusable lifting-body spacecraft, $18M to Boeing to develop a capsule with Bigelow Aerospace to launch on a variety of existing rockets, $6.7M to the ULA for an emergency detection system (needed for human-rating their existing rockets), $3.7M to the normally-secretive Blue Origin for developing a novel 'pusher' launch escape system and testing a crew module made of composite materials, and $1.4M to Paragon Space Systems to build and demonstrate a turn-key air vitalization system. SpaceX and Orbital will continue their earlier COTS contracts for cargo delivery to the ISS. Contracts in future years, totaling $6 billion over 5 years, will be competitively awarded based on performance and the goal of achieving safe, reliable, and cost-effective access to orbit.

Submission + - South Australian Political Speach Law Backflip (adelaidenow.com.au)

therufus writes: Earlier today Slashdot reported on South Australia outlawing anonymous political speech. Attorney-General Michael Atkinson, the very man who sponsored this, has now done a backflip saying "I will immediately after the election move to repeal the law retrospectively". He goes on to say "It may be humiliating for me, but that's politics in a democracy and I'll take my lumps".

Submission + - Rare Borland Memorabilia for Haitian Relief (webwire.com) 1

santakrooz writes: Embarcadero employees, many of whom are original Borland engineers and employees from the early Turbo Pascal, Quattro Pro, Paradox, JBuilder, Delphi and Borland C++ teams, are auctioning off rare and historical Borland memorabilia to raise money for Haitian Relief efforts. Proceeds are going to the Clinton/Bush Haiti Relief Fund.


Submission + - SPAM: Courts move to ban juror use of 'Net, social sites

coondoggie writes: If you think you're going to use your spanking new iPhone to entertain yourself next time you're on jury duty, think again. Judges are going to take an even dimmer view of jury member use of Blackberry, iPhone or other electronic devices as a judicial policy-setting group has told district judges they should restrict jurors from using electronic technologies to research or communicate.
[spam URL stripped]

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Submission + - Microsoft looking into Windows 7 battery failures 1

Jared writes: Microsoft says it is investigating reports of notebooks with poor battery life with Windows 7, as first reported by users on Microsoft TechNet. These users claim their batteries were working just fine under Windows XP and/or Windows Vista, and others are saying it occurs on their new Windows 7 PCs. Under Microsoft's latest operating system though, certain machines aren't doing so well, as Windows 7 spits out the following warning message: "Consider replacing your battery. There is a problem with your battery, so your computer might shut down suddenly."

The warning is normally issued after using the computer's basic input output system (BIOS) to determine whether a battery needs replacement, but in this case it appears the operating system and not the battery is the problem. These customers say their PC's battery life is noticeably lower, with some going as far as saying that it has become completely unusable after a few weeks of use. To make matters worse, others are reporting that downgrading back to an earlier version of Windows won't fix the problem.

Submission + - Oracle unplugs Project Wonderland (itworld.com)

Ian Lamont writes: Oracle has announced it is dropping support for Sun Microsystems' Project Wonderland. The Java-based virtual world developed some interesting features, such as voice communication with distance attenuation and phone-based access, but with Oracle's acquisition and integration of Sun, it seems that Wonderland didn't have a place in Oracle's strategic plans. An official blog post says a core group hopes to keep Wonderland going, and will be pursuing for-profit and not-for-profit options.

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