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Landmark Calculation Clears the Way To Answering How Matter Is Formed
First time accepted submitter smazsyr writes "An international collaboration of scientists is reporting in landmark detail the decay process of a subatomic particle called a kaon – information that may help answer fundamental questions about how the universe began. The calculation in the study required 54 million processor hours on the IBM BlueGene/P supercomputer at Argonne National Laboratory, the equivalent of 281 days of computing with 8,000 processors. 'This calculation brings us closer to answering fundamental questions about how matter formed in the early universe and why we, and everything else we observe today, are made of matter and not anti-matter,' says a co-author of the paper."
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Well, if there is no matter then certainly wouldn't matter as you wouldn't matter because there would be no matter to make someone like you ;-)
how is mater formed
how universe get axpadned
They ran the calculation on one core. They needed the other 8191 to render the Aero desktop.
Have gnu, will travel.
And the answer is 42?
There conceivably could be an infinite number of "parellel" universes, but there's a real philosophical problem with that. So long as we use the real physicists definitions and not something out of Stargate SG1, those parallels will always remain undetectable. SF writers tell stories about interacting with other universes - physicists define them in ways that show they can't be interacted with to be verified.
An untestable idea isn't part of science. If it can't be disproven, it's philosophy or religion or something instead. An infinite number of untestable ideas is even worse. Philosophers get to whip out Occam's Razor at that point. If I claim that there is not only a God, but 7 different orders of angels totaling 144,000 beings working for him, those numbers are still simpler, in the sense Occam's Razor usually means, and so are to be preferred as a hypothesis. The same goes for a Million gods with an avarage of four arms each and a bunch of hidden cyclic time periods totalling quintillions of years for them to do their work in, or any of those models with a reasonably sized bunch of gods, and maybe some giants, dwarfs, dark elves, ninja turtles piza delivery robots, a billion clones of an invisible pink unicorn who died for your sins, riding on a gigantic fiberglass replical of L. Ron Hubbard, and so on. Just about any other idea looks preferrable to an idea that postulates an infinite number of unverifiable consequents.
Who is John Cabal?
Biggest rock is best rock!
Frankly, it seems obvious to me...
I vote based on politicians' actions, unless contrary to my preconceptions. Often wrong, never uncertain. #iamthe99%
As someone who has just re-watched James Burke's "Connections" I have an answer for you:
Basic science *never* appears to have any immediate applications in the here-and-now. But someone, somewhere, is going to look at bits of it and say "ah, wait, I can use this over here" and either advance more basic science, or start applying it to technology, aka, applied science. But we don't know who, which, how, when, or why. In general, that is how all change happens. It is why we can't look into the future and see all the implications of what we create today. You don't know how someone is going to look at what you did and have an insight into something else because of it.
If you think something is useless because you, personally, can't see the implications of what something is, the problem is not with the science or technology, or social concept (like the creation of the first stock market in the Netherlands, for example) and you judge it such, the problem is with you and your myopia. Putting limits on what science gets done because immediate results are not readily apparent does nothing but hinder progress, and society (you and me and everyone else) loses out in the long run.
James Clerk Maxwell's equations had *zero* immediate implications for society at the time, but here we are 150 years later with a society that would absolutely fall apart without them - no radio, no computers, no high tech at all.
Anyone who says that basic science is too unfocused needs sit down and be quiet and let the adults talk.
--
BMO
In other words; basic research is absolutely critical to scientific advancement, and those that have to ask why are ignorant of how we got to where we are now.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Since the blog entry contains no reference - and the one hint there is is wrong - here is the actual article reference: Phys. Rev. Lett. 108:141601 (2012) - which was published on 6th April, not 30th March at the article states!
Now onto the physics, sorry but your summary is almost completely wrong. Kaons are mesons which are a bound state of a quark and anti-quark. In the case of neutral kaons this is a strange and anti-down (or vice versa for the anti-kaon IIRC). What is interesting about the kaon is that the neutral states can oscillate between kaon and anti-kaon through a weak interaction. What you end up with is a long-lived kaon (KL) and a short lived one (KS). The simplest way to demonstrate that this system differentiates between matter and anti-matter is to look at the long lived kaon decaying in to muons (heavy cousins of the electron). The number of anti-muons will be about 0.1% different from the number of muons produced.
However the decay to pions is far more closely studied because it can tell us far more information - in particular whether this symmetry breaking occurs in the decay mechanism (direct CP violation) or only in the weak mixing of a kaon to anti-kaon (indirect CP violation). The experiment I worked on as a grad student, NA48, observed this direct CP violation unambiguously for the first time, confirming the previous NA31 result. This ruled out more exotic types of CP violation from a new "superweak" interaction and, in broad terms, was consistent with the Standard Model.
However this was not really confirmation of the Standard Model because the actual calculation of CP violation occurring in the SM is really hard to calculate: it involves quark/W boson loops which must have contributions from all three generations of quarks (specifically including the top quark!). These so-called penguin diagrams (blame the name on John Ellis' dart playing skills!) are really hard to calculate - at least to the accuracy needed for CP violation in kaons. Kaons must decay through a weak interaction because only the weak interaction can change the strange quark into an up quark which is needed for pion decay. However there is also a strong component to the decay.
Strong (QCD) processes are really hard to calculate because perturbation theory does not work for them (the interaction is far too strong). One approach to solve this is lattice QCD which literally simulates all the colour (QCD) fields on a 4D grid of space-time points. However this is really CPU-intensive so only small grids can be simulated. This is not too bad if you have a strong process because, being 'strong' it happens quickly in a small region. However the weak part of the decay occurs more slowly over a larger area. What the authors seem to have done is overcome this simulation problem of both weak and strong forces in the same decay which raises the prospect of accurate calculations of the CP violation in kaon decays which has never been possible before. For the technically minded this paper calculates the Isospin=2 decay amplitude (A_2) whose phase shift, relative to the isospin 0 amplitude (A_0) is what makes direct CP violation visible - it's a really interesting paper - at least if you have ever been involved in kaon physics!
Fortunately, nobody else pays any attention to your kind.
Until they amass in large quantities of stupidity that cannot be ignored. I prefer to call them Christians...
"That's right...I said it."
How is this funny? Why would anyone mod this funny?
http://en.wikipedia.org/wiki/Significant_figures
there is still a niche for traditional supercomputers left...
I don't think you know much about supercomputers. Sure, there are a few problems that are embarrassingly parallel, but most aren't. For those that aren't, the bandwidth and latency of the interconnect between different processors is more important, and often more expensive, than the speed of the processors themselves. This is why most supercomputers use exotic interconnects like Infiniband, Myrinet or 10GigE, and linking nodes together using complex topologies such as a torus.
Case in point: on the website of the QCDOC supercomputer, which was partially used in this study, they say that a highly optimized lattice QCD simulation achieves up to 50% CPU utilization, and this is considered very good. The rest of the time is mainly spent waiting for the interconnect.
for i in `facebook friends "=bday" 2>/dev/null | cut -d " " -f 3-`; do facebook wallpost $i "Happy birthday!"; done
The phrase "a solution looking for a problem" was originally coined for the newly invented laser - everyone could tell that it was wicked cool, but nobody could come up with a good use for it besides maybe pumping a ton of power into it and setting fire to something far away.