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Lepton Universality In Question, a Standard Model Assumption
Charliemopps writes: "Over the past few years, more and more experiments have started to question one of the core assumptions of the standard model: Lepton Universality. Simply put, the weak nuclear force is assumed to work equally on all Leptons (electron, muon and tau). Two years ago The Babar experimental collaboration reported that measurements indicated this may not have been the case. But the measurements were not accurate enough to be definitive.
Now, a report from The LHC shows that they have analyzed their entire dataset of proton-proton collisions and found a rather large discrepancy. These measurements are still not all that accurate. These decays happen so rarely that even with this huge data set there is still about a 1% change they are incorrect. One explanation for such measurements is an as-yet-undiscovered, charged Higgs particle. It would have to be extremely heavy: greater than 109GeV possibly even as high as 150GeV. This is predicted by some models outside of the Standard Model, like Supersymmetry."
Now, a report from The LHC shows that they have analyzed their entire dataset of proton-proton collisions and found a rather large discrepancy. These measurements are still not all that accurate. These decays happen so rarely that even with this huge data set there is still about a 1% change they are incorrect. One explanation for such measurements is an as-yet-undiscovered, charged Higgs particle. It would have to be extremely heavy: greater than 109GeV possibly even as high as 150GeV. This is predicted by some models outside of the Standard Model, like Supersymmetry."
To "fix" it, just add one or more of the following to the model:
* More turtles
* More nested epicycles
* More dimensions
* Invent dark [something] to plug it
* Say God did it
Profit!
Table-ized A.I.
Except that that LHC's ongoing failure to find any SUSY particles is making it increasingly unlikely Supersymmetry is right either:
http://scienceblogs.com/starts...
Change you can believe in!
"chance", you idiots!!!
Gosh science is so expensive. Let's shut it down so we can remain ignorant fucktards forever!
The world's burning. Moped Jesus spotted on I50. Details at 11.
A new theory that will require an even more massive supercollider to prove or disprove!
Fine by me. Beats the hell out of another fruitless military adventure in the middle of nowhere or more pork barrel appropriations.
I could not find the 109-150GeV range in the original article, but the Higgs that has been found already has a mass around 126GeV. It seems like an additional Higgs in that range should already have been found by the LHC.
Finally! A year of moderation! Ready for 2019?
The Standard Model is an excellent computational tool - and little else.
With regards to Supersymmetry I have the feeling the LHC is going to end up being this century's version of Michelson-Morley.
However, given what happened after Michelson-Morley, we may be in for some very exciting new physics in the years to come if we can disprove Supersymmetry.
(At least I hope we are... :-))
Consider how long it took to gather enough of the right events to be reasonably certain about the Higgs, the various false alarms that vanished as more data was collected, etc. Another version just a bit rarer could easily be lost in the noise. Or the two could be similar enough that their signals aren't distinguishable from each other yet.
Wan't the confirmation just slightly different from what they expected.
The deviation might actually be traces of this unknown 2nd Higgs particle.
---- Sig. gone.
Um, what? Insane pseudoscience at its finest.
depends on what you consider properties of particles. after all, the position of the particle indicates its potential energy, thus two particles in different places are "different" in at least that respect. then there's also particle's speed, mass, etc., all of which could vary with energy, etc., on the other hand, ignoring those properties, all "electrons are the same" is likely a mostly valid statement.
We know this to be true because nothing can be perfectly split
Says what theory? This seems arbitrary and runs contrary to a large amount of particle physics, including some rather basic predictions of things of quantum mechanics and quantum field theory that would be covered in intro level courses on the topic. If the particles leaving an interaction were distinguishable and not "perfectly split," the results of the calculations would be off by a factor of two from measurements because of the way states work out, but they are not.
If a single particle cannot be split into two equal particles, then no two combination of particles can produce the same unique item again.
Even if the previous statement was true, this doesn't follow.
Therefore, all particles must be truly and absolutely unique in some fashion.
This seems to amount to circular reasoning in the end, and regardless disagrees with large number of experiments. This includes precision experiments that aren't about the basic assumptions of current theories, but checking that things like energy levels and things like charge of electron are constant and don't change because it is important to some work on redefining SI units.
And that's the problem with applying pop logic to a fuzzy understanding of a vastly simplified description.
Modern quantum theory suggests not only that two examples of the same type of particle are not only completely identical except for certain features like position, but that even talking about particles as if they had individual existence doesn't really make sense.
It is not just about the energy reachable, but the luminosity, which expresses how many particles it has interacting at relevant energy. Fermilab could have reached those energies, but the LHC has twenty times the luminosity, and at higher energy levels you can increase the chances of some reactions too even though they are at lower energy than the beam energy. This is why the next upgrade at CERN in ~2020 might not involve increasing the particle energy, but instead an increase of 5-10 times in luminosity which could be as important in answering some current questions.
When I grow up I'm going to Lepton University!
No wait...
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
Actually, you're entirely wrong. Subatomic particles of the same type are fundamentally indistinguishable from each other.
Don't just stand there, get that other dog!
Sounds like the simulation we are living in uses some de-duplication in the file system.to save space.
And a multiverse dos make sense?
As I could not find it on the arXiv (http://xxx.lanl.gov/), nor inspire (http://inspirehep.net) nor any official statement from CERN I assume this is just a preliminary result so far. Even as such I would expect some kind of estimate on the systematic uncertainties which go with this measurement. Without that it is not particularly relevant yet as those uncertainties could be substantial. So at the moment it is premature to talk about a discrepancy with the standard model (nor the previous measurements).
Is there really a 1% probability that they are incorrect or is there a 1% to get such data if they were wrong?
So, the idea that contrary leptons can be symmetric is absurd.
Not at all. Because, while your considerations are valid in a sense, you fail to take into account the fact that a 'particle' is an abstract entity - a theoretical construct that attempts to sum up a set of measurable characteristics in the data. Whenever we construct a theory, we are looking for things that are looking symmetrical and harmonic in some sense, so the elements in our theory will almost unavoidably be objects with this sort of universal properties.
Of course, being a only model means that any theory must fail at some point, when our observations become sophisticated enough, and that is probably what all true scientists are hoping for. The frustrating problem we have had for a long time is that we have observations that are not covered by our theory, but none of the predictions we have been able to produce with the help of our models turn out to be false. IOW, we know that our understanding of the universe is fundamentally flawed, but we can't see how or where. Things like the apparent problem with lepton universality may show us a way forward, so it is in fact very good news.
I applied to Lepton University and I just received a letter in the mail so I put it inside a box.
It is both a thick acceptance letter and a thin rejection letter. I'm not really sure where I'm going this fall semester.
Oh well, there's always Quark Community College, I guess.
Honestly.. a 2.6 sigma result? History is littered with 3 sigma results that vanish as more data is taken and detectors and other experimental hardware/software become better understood and modeled.
Gosh science is so expensive. Let's shut it down so we can remain ignorant [] forever!
Science in cheap, Big Science is expensive. So, yes, let's shut down some of the expensive Big Science experiments and fund hundreds of other smaller experiments in a range of different fields. No so flashy, but much better value.
Modern quantum theory suggests not only that two examples of the same type of particle are not only completely identical except for certain features like position,
Position is a property. If the information of 2 things are identical they are the same thing not 2 things.
but that even talking about particles as if they had individual existence doesn't really make sense.
However you divide the universe (or entagled existance at least) up this could be said to be true. It would take something as complex as the universe to model it fully though so to be able to make useful predictions we have to split it somehow.
If they have the same information they are the same particle. If they don't they are distinguishable.
Two hydrogen atoms are completely unique to one another...
That statement is false. Quantum mechanics deals explicitly with "identical particles", which are particles that are literally indistinguishable from each other, but are not the same particle. This is an empirically demonstrable violation of the principle of "identity of indiscernibles", which states that if two things are indiscernible any means whatsoever, even in principle, they are the same thing. Even though we have known this principle to be false for almost a century, philosophers still take it seriously for some reason.
There is a relatively simple proof that atoms of the same kind are indiscernible. The heat capacity of solids is a measure of how much the temperature goes up as you add energy to a block of material. The temperature is just the average energy per vibrational mode of the crystal lattice. The number of vibrational modes is intimately linked to the number of distinguisable particles in the crystal. N distinguishable particles have a different number of modes than N indistinguishable particles, so crystals will have a different heat capacity depending on which situation actually obtains.
This can be seen by considering a pair of distinguishable coiins vs a pair of indistinguishable coins. If we have two coins that are distinguished by the labels A and B, we have four ways of arranging them by which face is showing (H for heads, T for tails): AH/BH, AT/BH, AH/BH, AT/BT. If they are not distinguishable we only have three states: H/H, H/T, T/T because there is no way to distinguish AT/BH from AH/BT when we remove the labels.
So by a simple macroscopic measurements like the heat capacity of crystalline solids we can prove positively and directly by experiment that atoms of the same kind are in fact indistinguishable, and that the principle of the identity of indiscernibles is false. It is not false "for quantum particles" but false, absolutely--it just happens that quantum particles are the only case we know of where different particles are genuinely indiscernible from each other. But there is no limited domain of application to this result, and philosopher's attempts to treat it as somehow restrictive to the quantum domain are simply misguided (it turns out that the identity of indiscernibles being false makes nonsense of a bunch of other things philosophers want badly to believe, not least of which is how utterly useless the human imagination is in deciding what is and is not true of the world.)
Blasphemy is a human right. Blasphemophobia kills.
If they are "literally indistinguishable" the universe wouldn't be able to distinguish between them and so would be the same particle. If you can tell there are 2 particles they are distinguishable.
I read the headline as "Lepton University"
(1.21 gigawatts) / (88 miles per hour) = 30 757 874 newtons
That's correct: there were discrepancies that might-could-possibly have been caused by a Higgs+.
Or by any of a zillion other things, but it was a hypothesis that merited further experimentation.