And we're talking about builds, not in-use resource consumption... where it behaves just like every other browser.

Nope. It doesn't even behave like the 3.x series (of the very same browser, Firefox!) before rampant version number inflation. A perfectly serviceable "Athlon XP" based system with 750MB of RAM went from just fine to useless (in terms of firefox usage) at the version number break, under both Windows XP and Fedora. Memory footprint was my first suspect, but throwing in more RAM (up to 2.5GB now) helped but didn't make it completely better. Ironically, it's almost ok now under XP and still atrocious under Fedora.

Something baaad happened. But who cares about old systems, right? Only users, it turns out, not people triaging bugs.

Correct, it's a simple matter of 1/r^2 geometry. SN1987A was at 51.4 kpc. M101 is at 6.5 Mpc. So even if this was a core-collapse supernova (which it's not), we would see only 62-millionths of the signal as we did in 1987. Our detectors are bigger, but only 50 times bigger. We're still three orders of magnitude away from seeing this one with neutrinos.

Even a neutrino producing SN in the next big galaxy neighbor we have (M31 in Andromeda) would only give us about one neutrino event in our biggest detector (Super-K), which likely would go unnoticed. On the other hand, pretty much anything in our own galaxy or its small satellites will produce a huge signal. Space is a big, empty place.

And if you're curious and eager to learn about that once-a-century event before your slightly less-geeky buddies, check out the Supernova Early Warning System, sign up to get an email when we see neutrinos from a "nearby" supernova. Just don't hold your breath while waiting.

"eight megs and constantly swapping" used to be what emacs stood for. Imagine how svelte it would be if it were only eight megs today! Typed in a 173 meg firefox process, which is indeed positively svelte compared to the 700+MB it was yesterday - "firefox 4 is better and faster" my butt.

Do they? Or do they often collide with atoms and experience the same kind of "conversion"? As far as I know, nobody has performed any experiments to find out. The very idea that they might change from one form to another is very recent.

On the contrary, we've been doing experiments about this non-stop for decades, and the answer is "no, neutrinos don't interact very much". While the interaction cross sections with things have kind of large error bars by particle physics standards, they're still known to ~20%, and are Really Tiny. A good perspective - the mean free path for your typical neutrino is something like a light year of lead before it interacts with matter at all, and when it does, it's not doing flavor changing. How do we know? Since we can't build a light year of lead sized experiment to catch half of the neutrinos we shoot, we build them as big as we can and shoot trillions of neutrinos per accelerator pulse, run the thing every couple seconds for years at a time, and observe those few neutrinos which are so incredibly unlucky as to smack something dead-on. How dead on? The weak force has a range of ~10^-18m. A proton is only 10^-15m in size. So a neutrino happily passes straight through a proton most of the time, to say nothing of all the empty space in an atom (which are 10^-10m in size).

On the other hand, the data fit the hypothesis of quantum mechanical flavor mixing quite well. That happens regardless of the presence of matter. However, if there is a lot of matter in the way (say, solar neutrinos exiting the core of the sun) it is a big effect - the "MSW Effect" explains how the presence of matter nearby changes neutrino oscillations.

In the case of the earth (which has a comparatively puny mount of matter) the effects are a lot more subtle, but neutrino beams going through a lot of the earth should be sensitive to this in the next decade or so. The Japanese beam is comparatively short so isn't ideal for such a measurement, the under-construction NOvA experiment in the US will do better, and people would really like to do a Fermilab->South Dakota beam to nail it down in spades.

They don't need to measure the type of neutrinos they're emitting, they already know what type they are.

But if you measure what the neutrino beam looks like right after you make it (by sampling a tiny fraction of the neutrinos), then you get an even better measurement.

And T2K does - they have a whole suite of "near detectors" to carefully characterize what got made, and so can do a great "before and after" experiment.

Makes me wonder if the recent earthquakes put their aim off, possibly requiring recalibration at the sending end. I know this happens to radars after large quakes.

In fact, the quake shut down the neutrino beam, it will remain off till next year as they carefully line it up again.

This paper is from the data they got before the quake shut things down.

But they *do* measure individual neutrino interactions via the Cherenkov radiation emitted from their interactions in very large reservoirs of shielded heavy water.

Just regular water in this case. Very pure water (well over 100m attenuation length for light in that water), and a lot of it (50,000 m^3), but still just ordinary water.

Assuming this result is correct then this result implies that there is a CP symmetry violation between the neutrino and anti-neutrino.

The oscillation T2K just observed is not related to CP violation. It's simpler than that. There are three types of neutrinos. If they can change types, then there are three ways they could do so (draw yourself a triangle with each neutrino at a vertex, the sides are how they could change into each other).

Solar neutrinos start of as electron neutrinos and change on their way to earth (that's one of the sides). muon neutrinos are seen to change to tau neutrinos in Super-K's atmospheric neutrino signal and the MINOS accelerator experiment (that's the second side). This result is the first clear measurement of the third side, electron to muon changes. MINOS has made a similar but much messier measurement, T2K's is much cleaner.

CP violation is in the theory, but it's a second-order effect. That effect is multiplied by the size of this new electron/muon effect, so we need to measure this first, then we can look for "delta", the CP-violating phase.

(and yes, I Am a Neutrino Physicist - worked for many years on Super-K, now work on MINOS and Nova).

It would be one of the few legitimate excuses to submit a schematic drawing of your genitalia to a government office...

Sounds like a great way to get congressional support, seems at least several congresscritters would love to do this.

Work to fix the parts of the entry shaft which were damaged by the fire will stop public tours for the next few months, but we hope things will be back to normal at that point.

Yes, "normal" includes regularly scheduled lab tours as well as historical mine tours. If you're up in this part of the world for touristy reasons (most of which involve fishing and canoeing) definitely look up the Soudan Underground Mine State Park.

It is indeed at the Soudan Mine. Our website doesn't do a good job at explaining the smaller experiments which operate there, although we are working on fixing that.

Speaking as a physics prof, I wouldn't consider this cheating. We are well aware that old tests are out there. If people use them to study, fantastic! You're studying. Going over old tests is a great way to study. Cheating is copying solutons from the net and handing them in as homework sets. That's just plain stupid, since when you get to the test you won't have actually practiced how to do any of the problems, and you will bomb.

Now, if the prof in question simply reused a test wholesale, that might not be the best test of your abilities, but I bet that if you truely "studied every concept on that test", you would have gotten a good grade even if he'd cooked up a completely new test. There are only a limited number of concepts we're trying to teach you, after all.

On the other hand, I quite often recycle problems the class had issues with verbatim for finals. And tell the class "hey, remember that Gauss' Law problem from midterm #2? Study it". Those who go back and learn from their mistakes do well. A disappointing number of students still crash and burn.

Also for what it's worth - I agree that having the students memorize formulae is not so useful, in the real world you'd pull out your old textbook or go to the library and get one anyway. I generally tell students to bring a page of notes, I don't care what's on it. The very act of figuring out what they should put on their page is a good way to study. Unfortunately many students obsess so hard about copying down in 2-pt font every example problem available that they don't bother trying to understand how they actually work. And the whole point of physics is being able to figure out how stuff works, which is why you CS majors are made to take it. Problem solving skills transfer from free body diagrams to state graphs just fine.

Where this system wins out over the battery based system isn't in the efficiency of the electrical or pneumatic motor - it's the efficiency of being able to take in the braking energy quickly.

From memory (take that for what it's worth) a typical hybrid car can only convert ~40% of the inrush current you get when braking back into potential energy stored in the battery. A pump/tank system is about twice that efficient.

This is the same basic physics problem as why you can't recharge your laptop battery instantly, even though you really want to be able to get reloaded in the 10 minutes between flights you have left after you find a free socket in the gate area.

You would think it would be a no-brainer to have the SIM cards on some sort of custom phone plan which only allows calls to a fixed set of numbers, though.

My thoughts when hearing this story on the radio the other day:

"You can produce modified traffic lights that can do all this cool stuff, but then you can't lock the sim cards to that particular bit of proprietary hardware? Whiiiiiffffffff"

But the "change the calling plan" idea could be done quickly after the fact and save the rest of their installed base, that's even easier.

Anything in the public domain can't really be classified, let alone when its distributed in such a massive way like how Wikileaks does it.

No, the classification of a document isn't magically changed because it appears somewhere, and like it or not, the AF computer systems have to follow the rules about which documents end up in which security layer, regardless of source.

Regulations aside, think of this from a forensics standpoint. I'm sure the Air Force is (rightly so) rather interested in tracking down who leaked the stuff. That's a crime, and if you work for the Air Force, one you're liable for (as opposed to random people in Australia or Sweden, who aren't subject to those security laws). So - they're in the unenviable situation of having to track down who had access to which data when -- and suddenly copies of that data are pouring into systems from all over. That's going to muddy the trail a little bit, don't you think? How many more bogus hits on a phrase is the investigator's find/grep script going to turn up?

Finally, they are their computers, so they can do what they want with the content on them. C ensorship would be going out and telling other people what they can or can't do with their own systems. Big difference.