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Supersymmetry Theory Dealt a Blow
Dupple writes in with some news from the team at the Large Hadron Collider. "Researchers at the Large Hadron Collider have detected one of the rarest particle decays seen in Nature. The finding deals a significant blow to the theory of physics known as supersymmetry. Many researchers had hoped the LHC would have confirmed this by now. Supersymmetry, or SUSY, has gained popularity as a way to explain some of the inconsistencies in the traditional theory of subatomic physics known as the Standard Model. The new observation, reported at the Hadron Collider Physics conference in Kyoto, is not consistent with many of the most likely models of SUSY. Prof Chris Parke, who is the spokesperson for the UK Participation in the LHCb experiment, told BBC News: 'Supersymmetry may not be dead but these latest results have certainly put it into hospital.'"
Does this have to do with the decaying B Ray's they found?
First it was the Novell acquisition, then the Microsoft licensing... when will it end?
Can anyone explain some of the implications of this finding, for all the non-physicists on Slashdot?
The summary, like the article, jumps straight into "OMG CONFLICT" without bothering to tell us what's going on. From later in the article:
Researchers at the LHCb detector have dealt a serious blow to [supersymmetry]. They have measured the decay between a particle known as a Bs Meson into two particles known as muons. It is the first time that this decay has been observed and the team has calculated that for every billion times that the Bs Meson decays it only decays in this way three times. If superparticles were to exist the decay would happen far more often. This test is one of the "golden" tests for supersymmetry and it is one that on the face of it this hugely popular theory among physicists has failed. ...
The results are in fact completely in line with what one would expect from the Standard Model. There is already concern that the LHCb's sister detectors might have expected to have detected superparticles by now, yet none have been found so far.
But it sounds like this is only a problem for some variants of supersymmetry:
"If new physics exists, then it is hiding very well behind the Standard Model," commented Cambridge physicist Dr Marc-Olivier Bettler, a member of the analysis team. The result does not rule out the possibility that super particles exist. But according to Prof Parkes, "they are running out of places to hide". Supporters of supersymmetry, however, such as Prof John Ellis of King's College London said that the observation is "quite consistent with supersymmetry". "In fact," he said "(it) was actually expected in (some) supersymmetric models. I certainly won't lose any sleep over the result."
Visit the
Not to be confused with PUSY, which is still a mystery to most people here...
From TFA:
It's just a flesh wound!
Between this and the (possible) discovery of the Higgs Boson, we may be about to launch into a new era of particle physics theory and research.
Sheesh, evil *and* a jerk. -- Jade
The next big step is for them to 'prove' that what they found has more than just the mass they were expecting for the Higgs Boson. Just because something has the proper mass +/- some orders of magnitude, that was in a *very* wide ball park of their proposed Higgs, doesn't mean that it does what the Higgs is supposed to do. How they are going to actually prove that it gives all the other particles their mass, given they only know of its existence due to its decay mode (as in its already gone), is going to be one rather tough problem. We better get started...
See? Your science doesn't have all the answers.
Have gnu, will travel.
Here is the paper: https://cdsweb.cern.ch/record/1493302/files/PAPER-2012-043.pdf
Some blogs discussing the significance of the result:
http://www.science20.com/quantum_diaries_survivor/lhcb_evidence_rare_decay_bs_dimuons-96311
http://motls.blogspot.com/2012/11/superstringy-compactifications.html#more
http://profmattstrassler.com/
Particle physics isn't my field, but neither the paper nor the blog posts seem to be interpreting it, as the BBC does, as evidence against supersymmetry.
Find free books.
But i don't think it calls for a general breast beating about the standard model in general. We've certainly had to re-evaluate a lot since the 70s.
Between this and the (possible) discovery of the Higgs Boson, we may be about to launch into a new era of particle physics theory and research.
Actually, I think it's the reverse. Between this and the (possible) discovery of the Higgs Boson, we have simply just confirmed the parts of the standard model that we think we already understand. No new physics.
What people are actually looking for (and have found some hints/clues about like unexpected non-uniform decay paths in other experiments) are things that might suggests new physics that we don't understand at all which would launch a new era of particle physics theory and research. Some physists posit that some new physics exists (like SUSY) that might help us understand these hints/clues better, but so far the evidence has been lacking in support of a specific direction for new physics outside the standard model.
For example, the standard model doesn't seem to have a much of a say on the hierarchy problems (e.g., how come the higgs is so light), the observed electroweak symmetry breaking (e.g, why the higgs field yields mass), or give us much of a clue about dark matter (e.g., are there super heavy, neutral particles). As I understand it, as a straw man, SUSY might have something to help explain some of these deficiencies of the Standard Model, if there was evidence to support it.
If we keep running experiments and just find predictions that are supported/predicted by the Standard Model, we've only eliminated potential new physics, we need to find something that we can't predict to launch a new era of particle physic theory and research.
Good because I hated that fucking theory. Stupid piece of shit it was.
Choosing to miss your point completely, what if, for photons the spatial array is 1/2-spin particles, at least within their own system, for they don't exist in between fermions, in their own system .. then we might correspondingly expect that for fermions the spatial particle would be far more energetic yet again, but extremely short lived. Looking, then. At what happens as a neutron falls down a black hole, we see that one quark [say, a red] is closer to the event horizon than the others, and so is accelerated away from the others until the energy of separation causes pair production. Those pairs also string out similarly, so quark/antiquark strings are produced. The momentum in the direction of motion is huge, so the cross section in that dimension is tiny;but the momentum in the transverse directions decreases to zero, causing the waveform to expand out in that direction. Therefore the next stable structure that is formed will be that of extremely high energy, short-lived particles. By conservation of energy, they cannot gain energy forevere. By Heisenberg uncertainty, they will grow in transverse gross-section until they tunnel out of the black hole. At that point, they will interact with other relativistic quark/antiquark strings that are travelling in nonparallel directions, as well as with nonrelativistic fermions. This will then work to form a warped but generally thre-dimensiunal structure of short-lived, super-energetic particles that then function as a spatial matrix for the communication of electric, colored, weak andother forces. The gravity, then, is just a byproduct of tke spatial warping.
The summary isn't detailed enough to bring this up, but TFA tries to equate supersymmetry with dark matter, which is emphatically wrong. The existence of dark matter is strongly supported by astronomical evidence including galaxy rotation velocities and observations of gravitational lensing, regardless of the nature of the particles that make it up. Even if this result provides evidence against supersymmetry (which doesn't seem to be the conclusion of other articles I've read, although I'm not really qualified to say), it tells us absolutely nothing about dark matter.
So, one breast is bigger than the other?
Table-ized A.I.
Wrong. If it is evidence against supersymmetry, it tells us that dark matter is likely not composed of supersymmetric particles. Given that supersymmetric particles are one of the main hypotheses about what dark matter is composed of, I'd say it tells us very much about dark matter.
What you probably wanted to say is that evidence against supersymmetry is not evidence against dark matter.
The Tao of math: The numbers you can count are not the real numbers.
Science was wrong, therefore the Bible is proven completely inerrant.
I thought Nature wasn't that rare, it has plenty of subscribers. On what page was the particle?
Einstein's revolution was sparked by a moment of insight.
Wrong, it was the result of long hard work by several people.
It all started when Maxwell's equations gave results that did not agree with newtonian physics. In an attempt to get at the root of things, Michelson and Morley created an experimental setup to measure the speed of light in different directions in a very precise way. To everyone's astonishment, these experiments indicated that the speed of light is a universal constant, which does not depend on either the movement of the light emitter nor the movement of the detector.
Which was exactly what Maxwell's equations had predicted to begin with! If there was a true intellectual giant here, it was Maxwell.
Several scientists started creating equations that made the results of the Michelson-Morley experiment compatible with classical mechanics. Einstein was just the most successful one, because his equations were more elegant and simpler than those of the others.
However, this does not mean Einstein was absolutely right, his theory was only the best one for that particular period. Today we know things he didn't know, just as Newton didn't know that the speed of light is constant.
For instance, there IS a fixed frame for the whole universe, the one in which the cosmic background is symmetrical. This background was discovered only in 1965.
There's also the horizon problem, which was discovered only in the 1970s. If we look at the sky in opposite directions, we see the same characteristics. We are looking at different regions of the universe that never had contact with each other since the creation of the universe. They are so far apart that even light couldn't have reached one from the other during the universe's lifetime. To solve this problem in a way that's compatible with einsteinian relativity, cosmologists came up with cosmic inflation, a rather ugly and contrived kludge.
Besides, relativity does not give results that are compatible with quantum physics, this has been demonstrated experimentally.
It's rather unfortunate that Einstein's theory is so elegant and precise, because it's certainly wrong when your size scales too much up or down.
LHC energies are a minute fraction of what will be needed to find super partner particles. But admitting that is bad for business.
Futility? Really? The SM is incomplete, in that you have to plug and chug 17 constants that can only be determined via observation. This incompleteness may not be wrong, per se, but it certainly means that refining the SM is unlikely to be the optimal path towards truth. What is the optimal path? You tell me. But spending a lot of resources on a theory that is known to be incomplete and can never be made complete, when there exist other theories that don't have those issues, sounds like the very definition of futilty to me, ranking up there with rain dances.
just for the record, in order to warn any non-westerners:
"The cost [...] has been evaluated, taking into account realistic labor prices in different countries. The total cost is X (with a western equivalent value of Y) [where Y>X]
source: LHCb calorimeters : Technical Design Report
ISBN: 9290831693 http://cdsweb.cern.ch/record/494264
http://cdsweb.cern.ch/record/1127343?ln=en
From other places. Be proud for once, Occident invented it alone without prompting. Though someone may be forgetting time somewhere... Ditto.
Supersymmetry Theory would be a great name for a tech in Alpha Centurai 2 (if\when it gets made), so it'll be a shame if this gets disproven further.
I'm sure they can adjust some variables to make it fit back into their model. There is a consensus after all.
but the theory is in another castle.
Wave bye-bye to Lambda-now-falsified cosmology theory. :)
It was a conjecture! If you are going to define "Theory" as being supported by a preponderance of evidence, as we do when we say, "The theory of evolution." then we can't keep going around calling every damned conjecture a theory too.
What the hell is so wrong with the word "conjecture"?
Susy dealt a heavy blow at the Large Hadron Collider If you can't laugh at that statement then you are dead.
I haven't thought of anything clever to put here, but then again most of you haven't either.
TFA tries to equate supersymmetry with dark matter, which is emphatically wrong.
No it doesn't. It equates SUSY particles with Dark Matter candidates, which is completely true.
The enemies of Democracy are
A replacement which has approximately five times as many doesn't seem too desirable to me.
Actually I used to feel the same way - that ultimately we should have a theory with 0-1 free parameters until a colleague pointed out another possibility. Suppose you have a universe where there are many free parameters but, ultimately, the physics ends up being pretty similar regardless of their actual choice? Since then I've been a lot less hung up on the idea of free parameters despite the fact that neither scenario is applicable to SUSY!
SUSY was invented to explain why the Higgs mass is around 126 GeV/c2 (assuming it is the Higgs we have found) while gravity gets important around 10^18 GeV. If there is nothing else but the SM and Gravity then you have to have a truly amazing coincidence equivalent to winning the UK national lottery about 5 times in a row. While this is technically possible if someone won the lottery that many times in a row you would not be thinking "wow, what a coincidence" but "how did the manage to do that?". It's the same with physics: nobody believes that this is the result of random chance but that there has to be some mechanism by which the universe makes the Higgs mass so small compared to gravity.
Interestingly SUSY does not stop there. It also provides an excellent Dark Matter candidate, makes the weak, strong and EM forces unify at a single point and also turns out to the highest order symmetry possible in our space-time...but it was not conceived of to do any of this at all! When "coincidences" like this happen you really start to feel that you are onto something big so the hope is that some model of SUSY is out there in the universe despite the issue with the ~120 free parameters (which would very likely rapidly decrease from 120 if SUSY were found).