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Comment Re:I'm dumb, I think. (Score 2, Informative) 194

There's a few things going on here that are related in different ways.

1) The single-top isn't the only quark being produced, it's actually produced with a bottom quark at the same time. Usual top quark production is in pairs, one top quark one anti-top quark, but single-top is different; a top quark is produced with a anti-bottom quark.
2) The top quark decays before it can hadronize. That is, it decays before it can pick up a partner quark. This is completely allowed in the Standard Model, but I'm a bit sketchy on the details. I think it behaves as though it was attached with the other quark it was produced with.

Comment Re:Explanation wanted (Score 4, Informative) 194

The fine article says that this results limits the number of possible quarks. Can someone give an explanation (or even the outline of one) at a level that someone with a B.S. in physics can understand?

One of the things single-top is sensitive to is the coupling strength of the top and bottom quarks via the weak force. The value of this coupling is tightly constrained if one assumes that there are only six quarks (ie. there are three generations of matter). The fact that they measured it and it's within the six quark ballpark means that it is very likely that there isn't another pair of quarks waiting to be discovered.

The basic idea is that if the top and bottom coupling strength is measured to be less than the value we expect for six quarks then that means that some of that coupling strength actually goes to a different, seventh or eighth, quark. But I'm grossly simplifying things here for the general slashdot crowd.

Comment Re:Bare/Single quark? (Score 4, Interesting) 194

This is not a major discovery, but it is another important showing off of the 'standard model' working very well at the energies we have so far probed.

Single-top is, however, one of the backgrounds in the search for the Higgs boson. For Fermilab to discover the Higgs, they have to discover single-top first.

Comment Re:it's a faked signal (Score 4, Informative) 194

Emphases mine... I am not convinced this isn't a faked signal. With that possibility having a chance of one in four million, how many millions of collisions have they done in the past 15 years? Far more than 4 million, I would suspect.

You aren't quite grasping what he means by one in four million. This wasn't a single event we are talking about here.

The way the statistics work is that you would have to run the entire Fermilab experiment four million times to get what they see from a fake signal. It's a cumulative probability over all the events ever recorded at Fermilab.

...and another thing. Look at that diagram showing a muon went here and a neutrino went there - how in the world did they detect that neutrino, I ask? I bet it zipped right through their detector without so much a pausing to say hello.

They didn't detect it directly. The key to 'detecting' the neutrino is to count up everything else in the remnants collision and notice that it recoils off of something that you didn't detect. It acts as though what you can see in your detector is violating the conservation of energy. But in reality there's an undetectable neutrino zipping through the detector. So you calculate how much energy and in which direction such a neutrino would travel in order to conserve energy, and that's where they get that little diagram.

Comment Re:Too many loopholes (Score 1) 230

Arbitary codes like this and One time pads have been proven (when done correctly) to be absolutely secure, whereas all encryption in theory is insecure (the only exception is quantum encryption)

The thing is, quantum encryption is a one time pad system. It's a secure way of distributing the one time pad.

Privacy

Submission + - UK to imprison for inability to decrypt data

mrbluze writes: Ars technica has an article describing new laws which come into effect on 1st November in the UK. Up to 2 and 5 years imprisonment can be inflicted on any person who refuses or cannot provide keys or decrypt data as requested by police or military for criminal or anti-terror purposes, respectively. From the article:

The Home Office has steadfastly proclaimed that the law is aimed at catching terrorists, pedophiles, and hardened criminals — all parties which the UK government contends are rather adept at using encryption to cover up their activities.
It refers to a potential problem faced by international bankers who would be wary to bring their encryption keys into the UK. Some how I doubt that is the real problem with the law.
Announcements

Submission + - New Record Superconductor Discovered

Dean Edmonds writes: "Superconductors.org is reporting a new record for high-temperature superconductivity. The new material shows both resistive and Meissner transitions around 175K (-98C), 25 degrees higher than the previous record holder. To put that in perspective, the coldest temperature ever recorded on Earth was 184K (-89C) at Vostok Station, so we're getting close to 'room temperature' superconductors, just so long as the room is in Antarctica."
The Internet

Submission + - Cops subpoena to learn who read critical web pages

solareagle writes: A weekly newspaper has received grand jury subpoenas seeking information on who visits their Phoenix weekly's Web site. Maricopa County authorities want every story New Times has written about Sheriff Joe Arpaio since Jan. 1, 2004, including one that revealed the sheriff's address. The subpoenas also seek online profiles of anyone who read four specific articles about Arpaio and profiles of anyone who visited the paper's Web site since Jan. 1, 2004. Also sought was information on what Web users did while on the site. When the newspaper published a story revealing the subpoenas, its editor was arrested for revealing grand jury information. He now faces up to six months in jail and $2500 in fines. Former New Times reporter John Dougherty, whose original story about Arpaio's address sparked the controversy, said: "We're not harboring state secrets, we're not harboring terrorists, we're just straight up reporting on issues they don't want us to report on."
The Almighty Buck

Submission + - Defense Asks Judge to Overrule RIAA Payout

Damocles the Elder writes: Well, the RIAA won, but now a Minnesota woman is appealing the judge's decision on the basis that $222,000 is unconstitutionally expensive for 24 songs. FTA:

The petition to U.S. District Judge Michael Davis, among other things, challenges the constitutionality of the 1976 Copyright Act, the law under which the RIAA sued Jammie Thomas of Minnesota, as well as over 20,000 other defendants. The $750 to $150,000 fines the act authorizes for each download is unconstitutionally excessive and against U.S. Supreme Court precedent, wrote Brian Toder, Thomas' attorney.
Naturally, the RIAA is claiming the argument is "baseless", but if this gets set as a precedent, it won't matter if the RIAA wins the lawsuits if they're only getting a couple dollars a song. Needless to say, many people will be following this with interest.
The Courts

Submission + - MN Woman first to go to trial for music sharing (wcco.com)

TDDeYoung writes: "A Minnesota woman is going to trial against the RIAA (specifically Virgin Records America Inc., Capitol Records Inc., and Warner Bros. Records Inc., and there may be a few more) over charges that she illegally shared music on Kaaza. This will be a jury trial. Already the judge has thrown out some 700 pages of documents produced by the record companies that supposedly showed that they owned some of the songs. The defendant's lawyer argued that the documents were seven months late. The EFF gets a mention and a quote in here too. This should be fun to watch."

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