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Comment Re:Nice pix (Score 4, Informative) 67

The "star filters" you mention are actually diffraction spikes caused by the rods that support the secondary mirror of the telescope. They are an intrinsic quality of the telescope. If you look at the left side of this image of the Hubble under construction you can see three (of the four) black spokes that connect the outer cylindrical support to the cylinder in the middle (this is where the secondary mirror is mounted to). It is the light diffracting off of these spokes that cause the starburst pattern that you noticed.

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.

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