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"Perfect" Electron Roundness Bruises Supersymmetry
astroengine writes "New measurements of the electron have confirmed, to the smallest precision attainable, that it has a perfect roundness. This may sounds nice for the little electron, but to one of the big physics theories beyond the standard model, it's very bad news. 'We know the Standard Model does not encompass everything,' said physicist David DeMille, of Yale University and the ACME collaboration, in a press release. 'Like our LHC colleagues, we're trying to see something in the lab that's different from what the Standard Model predicts.' Should supersymmetrical particles exist, they should have a measurable effect on the electron's dipole moment. But as ACME's precise measurements show, the electron still has zero dipole moment (as predicted by the standard model) and is likely very close to being perfectly round. Unfortunately for the theory of supersymmetry, this is yet another blow."
"ACME collaboration"?
Then just bang the electron on the head with an ACME anvil, and it will grow lumps.
Table-ized A.I.
Because since protons prefer round, smooth booties, they won't date neutrons, which then fly off into space to shop. Didn't you learn anything in science class?
Table-ized A.I.
If you measure it, an electron is perfectly round. The rest of the time it's kind of oval.
http://www.youtube.com/watch?v=hhbqIJZ8wCM
I have been on the edge of my seat waiting for something genuinely new. Something like when people were discovering that atoms were made up of even tinier bits. Or that quantum was not just a mathematical nicety but way cooler. Each of these fairly "academic" discoveries then opened up whole new trains of thought that led to lasers, solid state electronics, nuclear reactors, etc.
So what wonderful physics is hiding out there waiting to be discovered and open up a whole new world to us?
Personally my biggest recent letdown were the FTL neutrinos that turned out to be bogus. I was genuinely hoping that something cool revealing itself. But alas. My favorite today is that entanglement and wormholes might have some relationship. Minimally that will result in some cool sci-fi if not actual science.
Personally I don't mind if ultraspherical electrons shut down a bunch of pet theories. They didn't seem to be making much progress and thus the door has been opened to explore something new. Maybe there is some guy trying to get his doctorate showing that supersymmetry is a load of rubbish but hasn't been able to get much traction because the entire panel got their doctorates in supersymmetrical related ideas and in order to defend his thesis he has to first set fire to theirs.
Science is going to be really screwed when they discover frictionless planes also exist.
Because string theory isn't science!
If it's spherical what's the size of that sphere?
Every time I see a news item about supersymmetry, it always seems to be disproving it. Seems like the only thing the hypothesis has going for it is the universe would make a lot more elegantly designed if it was true. It seems like mostly wishful thinking to me.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
The Wikipedia article on supersymmetry did not really seem to help within the context of the electron smoothness issue.
... of models involving perfectly spherical atoms, nanoparticles, cows, planets, stars, etc, there is something ironic about an electron being too round.
From TFA
The standard model predicts that the electron has exactly zero dipole moment, meaning it is perfectly symmetrical. However, should supersymmetry exist, the dipole moment of the electron should be greater than zero, pushing the negatively-charged particle into a a more and more elongated shape.
The deviations they are talking about aren't things like mountains or bumps, but a systematic non-spherical bias.
For example, the earth isn't spherical either, it's basically a bit fatter around the equator pretty close to an oblate spheroid (e.g., an M&M is a more exaggerated oblate spheroid). Like a baseball, if the electron isn't totally spherical, you can detect a systematic bias as it's being thrown around (you can think of the LHC as throwing an electron spit-ball or a knuckle-ball).
Although even in the standard model, the electron at some energy level probably has a detectable dipole moment (e.g., the charge wouldn't be uniformly spherically distributed in the electron), it is my understanding that it is predicted to be too small to be validated by current experiments. However, some versions of super-symmetry apparently would predict that the electron at some energy levels would have a larger detectable dipole moment . I guess these super-symmetry predictions didn't pan out.
I thought that, since it wasn't made up of sub-particles, an electron was a point particle. Since when does it have a defined size, let alone shape?
How can anything have a shape that turns into an electromagnetic wave when you're not watching...
bickerdyke
A perfect sphere IS super-symmetrical so long as the cut goes through the center. Good thing I'm here to help out these scientist.
http://en.wikipedia.org/wiki/Supersymmetry
A whole lot of PhD dissertations, physics publications, and academic careers are on the line over this. String theory is the current favorite and loop quantum gravity the underdog. The direction of theoretical particle physics could be radically altered if the LHC doesn't find evidence of supersymmetry.
Why is Snark Required?
The Standard Model doesn't predict that the electron EDM is zero.
if it had bumps that didn't really effect the charge distribution...
... and this is exactly where the headline implies it wrong. If you actually read beyond the headline (merely the slashdot summary is already enough), you'd notice that this is indeed about non-roundness that does affect charge distribution. Non-uniform charge distribution would result in a dipole moment, whose absent has been noticed.
smallest precision attainable does not mean what you think it does. You meant highest precision attainable
Because string theory isn't science!
Sure it is. It's abstract mathematics.
Yeah, but the summary nor the article explain why supersymmetry is a question or an issue in the first place, just that the evidence doesn't support the theory. What does the theory it disproves mean/change?
I do not fail; I succeed at finding out what does not work.
Perfectly round. Isn't that the definition of super symmetry?
Depends. Is the inside the same as the outside?
Because since protons prefer round, smooth booties, they won't date neutrons, which then fly off into space to shop. Didn't you learn anything in science class?
Neutrons just don't want to get involved.
So basically.... evidence supports the standard model and someone's pet theory that they are hoping will make them the next Einstein has evidence that is contrary to it?
"Lack of speed can be overcome. In the worst case by patience." --Znork
you forgot Polan... ahem, the axis of evil. The related article cites coincidence as a possible interpretation, which seems a "Galileo" moment to me.
---- MISSING MISCELLANEOUS DATA SEGMENT --- [sigdash] trolololol
An aspect of science is applied math as the AC below mentioned. More particularly, we should be somewhat cautious in treating math as physics. Physics is describable in math, but it isn't math. And the mathematics of a physical situation functions more like an analogy. It says "that works like this"...and usually it does that to some epsilon because we can only measure up to a certain energy. One can think of a physical theory described in mathematics as an idealization. The math is very precise, the real world is not necessarily.
Electrons are point particles - modelled as zero-volume and massless. They might have no physical form. I am not surprised that our measures of them indicate perfect symmetry.
What I'm not interested in is smug assholes claiming "it's in the summary" when it's not.
I do not fail; I succeed at finding out what does not work.
Perfectly round. Isn't that the definition of super symmetry?
Depends. Is the inside the same as the outside?
Frat boys on college campuses, near bars on Friday nights.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
This is a good question. There are a number of theoretical and empirical motivations for supersymmetry, including the existence of dark matter, the matter-antimatter asymmetry in the universe, and the hierarchy problem in particle physics. I don't fully understand all of these myself. However, this short video released by my collaboration tries to explain some of them at a basic level: http://www.youtube.com/watch?v=UIflReRmynk.
You seem to be implying that somehow mathematics are not sufficient for describing the "real" world, and that is simply not the case.
Mathematics are the language of the universe, as far as we can tell.
It says that supersymmertry predicts a larger dipole moment, that's why it would be in question.
If you want to know why supersymmetry makes that prediction then you aren't going to get that in a new article or a slashdot post. There are lots of resources available for learning SUSY, or jump in the deep end with something random like http://www.springer.com/physics/particle+and+nuclear+physics/book/978-4-431-54543-9
You seem to be implying that somehow mathematics are not sufficient for describing the "real" world, and that is simply not the case.
Mathematics are the language of the universe, as far as we can tell.
I agree. A better statement might be that our understanding of mathematics is not sufficient for describing the "real" world. The problem is not math itself.
The trouble is that Mathematics can describe ANY universe, not just the one we happen to be able to perceive.
Math is great at describing perfect theories that fail to pan out in real life, but that are perfectly self consistent in the theory and equations. Just look at all of the great, and completely wrong, models offered in super-symmetry, string, and all the other Grand Unified Theories that mathematically are perfectly sound, but are disproved by actual experiment.
This is why Physics, e.g. "science" > Math.
"Unheard of means only it's undreamed of yet,
Impossible means not yet done." ~~ Julia Ecklar
You seem to be implying that somehow mathematics are not sufficient for describing the "real" world, and that is simply not the case.
Mathematics are the language of the universe, as far as we can tell.
Speaking as a person who does mathematical modeling for a living, I can tell you that a mathematical model is definitely only an approximation for the real world. There is no such thing as a perfect model due to the limitations of our knowledge and our inherent inability to model every single detail in the world. There are huge stochastic effects that we can only approximate statistically (a deterministic model would require a near infinite number of parameters, and even it would be an overfit because we cannot measure or determine the all underlying phenomena).
Mathematics cannot be the language of the universe as the vast majority of the universe does not communicate any ideas. The parts of it that do is an insignificant, tiny portion that includes us and whatever other self-aware/reasoning beings that may be out there.
What mathematics is are a set of insanely great tools that we use to create models helping us to describe the universe. One thing we've learned from math is that self-referential systems tend to have issues that can crop up in spots. And it's hard to get more self-referential than a subset of the universe trying to understand the whole thing.
Saying that mathematics is sufficient to describe the real world, no matter how successful it has been at it so far, is awfully presumptuous.
Happy people make bad consumers.
My point was that mathematics is a science. That it is a formal science instead of a natural science is a different matter all together.
It's a bit complex to squeeze into a slashdot summary. Here's what has to say about it. This article, written by Theoretical Physicist Matt Strassler, does a better job of explaining it in layman's terms, I found it to be an excellent article. I'd had only the vaguest idea what it was about before reading it.
Now I have a much less vague idea, but reading an article by a physicist doesn't magically turn you into one.
Free Martian Whores!
Supersymmetry solves an enormous number of problems in particle physics, except for experimental facts.
Unfortunately for the theory of supersymmetry, this is yet another blow.
Ok, but why? Anyone care to explain this for me?
In simple terms (that I hope are accurate), supersymmetry is one of the predictions made by string theory (although the concept of supersymmetry pre-dates string theory). I believe there are other theories that incorporate supersymmetry as well. So, if the predictions made by supersymmetry don't hold up, any theory that is based on it will need to be revised or abandoned.
To defend Mathematics a bit, it does tend to advance much more quickly than Physics since it isn't hampered by the restrictions of the real world.
Just think of General Relativity and non-Euclidean Geometry. Often times when a new scientific concept is created/discovered and a model is required to flesh it out, all you need to do is look around existing mathematics and, oh look, there's an app for that.
Happy people make bad consumers.
On a side note:
"The most incomprehensible thing about the universe is comprehensible" said Einstein.
I never fully got why it was a big deal, but I'm pretty sure "comprehensible" in this sentence is about describing it in math.
See also: http://en.wikipedia.org/wiki/The_Unreasonable_Effectiveness_of_Mathematics_in_the_Natural_Sciences
Because string theory isn't science!
A more accurate statement is that string theory is math not physics.
I'm a good cook. I'm a fantastic eater. - Steven Brust
Godel's Incompleteness Theorem basically proved otherwise.
This is why Physics, e.g. "science" > Math.
Your logic is wrong (as well as your use of e.g., which means "for example"). The only thing you've concluded is that physics != math. By your own words, math can describe any universe. In that case, only one math describes ours. We haven't quite worked out what that math is, but that's why all these competing physics theories exist.
There are no competing math theories, because mathematics isn't trying to describe reality.
"If a nation expects to be ignorant and free in a state of civilization, it expects what never was and never will be."
This is an EXCELLENT video. Thanks for the link.
http://www.youtube.com/watch?v=UIflReRmynk
More accurately, The Standard Model is the best theory we have right now but it's incomplete since it doesn't account for gravity and has a lot of parameters that are just there without a good explanation for them. Supersymmetry is an idea that is the basis for a lot of people's pet theories because it helps explain a lot of what the Standard Model does not by bringing in a lot of extra particles.
Those particles, if they exist, make other particles like the electron behave just a little differently than they do under the Standard Model. And this experiment provided evidence that supports the Standard Model and rules out a number of Supersymmetric pet theories. Whether or not it will rule them all out remains to be seen.
Does this