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Re:CERN experiment discovers five new particles by teddythetwig on Tuesday March 21, 2017 @08:16AM (#13921479)
I assume these particles were already predicted as part of the Standard Model?
Re:CERN experiment discovers five new particles by sidlls on Tuesday March 21, 2017 @10:04AM (#13922258)
Yes, but these experiments serve at least three purposes.

One, to verify the Model (after all, if its predictions fail in some part it will have to be revised).

Another, to verify the characteristics of the predicted particles (there might be some differences from the prediction that are important, but not hypothesis-breaking).

Finally, however unlikely and yet most excitingly (to me at least), to open new avenues of questioning and hypothesis up by really throwing into question some things.

Re:CERN experiment discovers five new particles by M_Grey on Tuesday March 21, 2017 @11:20AM (#13922952)
It's worth remembering that the Higgs particle was also predicted by the standard model, and no one underestimates the importance of that confirmation.
Re:CERN experiment discovers five new particles by whyever on Tuesday March 21, 2017 @01:06PM (#13924098)
The Higgs is an elementary particle, so its discovery was much more exciting. There are a lot of particles made up of quarks, like the five mentioned in the article:

http://pdg.lbl.gov/2016/tables/rpp2016-qtab-mesons.pdf http://pdg.lbl.gov/2016/tables/rpp2016-qtab-baryons.pdf

Re:CERN experiment discovers five new particles by lngnmn on Tuesday March 21, 2017 @02:31PM (#13924840)
What is at least one single scientific (replicated) evidence that these tables does not contain merely a socially constructed crap, modern day alchemy deduced from flawed models and/or instruments?
Re:CERN experiment discovers five new particles by whyever on Tuesday March 21, 2017 @04:23PM (#13925879)
These tables are editorialized by the Particle Data Group, they summarize and distill the empirical evidence of thousands of high-energy physics experiments. Not every experiment is replicated, but some are, hence the different ratings of how sure the editors are the particles exist.

From their website:

"In the 2014 Review, the listings include 3,283 new measurements from 899 papers, in addition to 32,000 measurements from 9,000 papers that appeared in earlier editions. Evaluations of these properties are abstracted in summary tables."

http://pdg.lbl.gov/2016/html/what_is_pdg.html

Re:CERN experiment discovers five new particles by lngnmn on Tuesday March 21, 2017 @04:31PM (#13925947)
> probability, statistics, accelerators and detectors

Surely, there could not be any error here. Nothing socially constructed.

Isn't it already borders nonsense that in the universe which is sustained by a couple of fundamental conservation laws there supposed to be hundreds of elementary (presumably fundamental) particles which emerge and disintegrate in time, which is not even an intrinsic property of "more real" things like photons.

Re:CERN experiment discovers five new particles by whyever on Tuesday March 21, 2017 @07:28PM (#13927241)
> Surely, there could not be any error here. Nothing socially constructed.

There could be. Physicists have been trying very hard for the last 40 years to find something the standard model cannot explain, without success. Some experimentalists are actually disappointed about this.

> Isn't it already borders nonsense that in the universe which is sustained by a couple of fundamental conservation laws there supposed to be hundreds of elementary (presumably fundamental) particles which emerge and disintegrate in time, which is not even an intrinsic property of "more real" things like photons.

You are confused. The standard model has 17 elementary particles (+ anti particles). There are a lot of composite particles, like the ones the article talks about. Not sure what you mean about decays, but photons are a special case, because they move at the speed of light. Other elementary particles, like the heavier quarks, can and do decay.

Re:CERN experiment discovers five new particles by krastanov on Tuesday March 21, 2017 @03:36PM (#13925454)
Given that science is done with models and instruments I am confused what answer you expect. Those models and instruments are validated in thousands of different experiments, at different energy and length scales, from astronomical observations to man-made particle accelerators. Each of the experiments and observations testing slightly different part of the theory, all of them mostly in agreement. It is the rare disagreements that are actually most exciting, because they pave the way forward to pieces of the theory we do not understand yet.

Here are two independent examples that agree in their results: experimental measurements at the LHC; theoretical​ predictions from QFT.

Re:CERN experiment discovers five new particles by lngnmn on Tuesday March 21, 2017 @03:54PM (#13925607)
Why, there are way too many well-documented instances of socially constructed and socially accepted bullshit in the history of mankind. Actually, it is much difficult task to find instances of accurate approximations to the truth.

There has been times when Hegelian "logic" has been accepted, published by Oxford University press, peer-reviewed, highly praised and successfully taught to students. I have read parts of Encyclopedia of the Philosophical Sciences. I have read it after The Principles of Mathematics and things like Haskell Prelude.

I have read peer-reviewed commentaries to The Highest Yoga Tantra and such crap like commentaries to Hatha Yoga Pradipika by some Australian lady with some funny Hindu nickname.

I have read even beautiful sufi texts in which they freely mix and match anthropomorphic qualities to produce a beautiful carpet of linguistic patterns which describe nothing that exist. Peer-reviewed and highly praised, of course.

Socially constructed nonsense is not something rare and uncommon. To the contrary, most of publicly available information is bullshit, or at least highly inaccurate, full of meaningless generalizations, flawed logic and amounts to nothing but mere compilation of current memes.

So, I am more or less familiar with how such things could emerge. My question is - what is a single falsifiable experiment which proves that this is not socially constructed, highly sophisticated sectarian set of beliefs supported by complex (but meaningless) simulations (instead of mere a book of dogma).

Re:CERN experiment discovers five new particles by sqeaky on Tuesday March 21, 2017 @08:09PM (#13927486)
You are barking up the wrong tree.

There is plenty of stuff in science that is imperfect and deeply flawed. Look at all the poorly reproduced studies on various nutrition and health products, for example. The Standard model is not part of that weak set.

The way to oppose social construction is increased rigor and experimentation. The Standard Model has some of the highest rigor and largest amount of experiments backing it.

Re:CERN experiment discovers five new particles by macintux on Tuesday March 21, 2017 @07:54PM (#13927407)
Skimming through your comment history it's obvious you have a bone to pick with modern physics. Is there some discrete point in history where you think we started diverging from falsifiable experiments so we can perhaps compare before and after?
Re:CERN experiment discovers five new particles by dogecoinbase on Tuesday March 21, 2017 @08:19PM (#13927530)
My question is - what is a single falsifiable experiment...

Can you describe how such an experiment might be constructed?

Re:CERN experiment discovers five new particles by cynicalkane on Tuesday March 21, 2017 @11:53AM (#13923320)
Not in the same way. There was no experimental evidence for the Higgs field before the Higgs was observed. These new particles arise naturally out of parts of the Standard Model that are already experimentally tested.
Re:CERN experiment discovers five new particles by M_Grey on Tuesday March 21, 2017 @11:56AM (#13923358)
You're not wrong, but you'd have been really hard-pressed to find someone of significance who didn't already believe the Higgs mechanism was there. In the sense that mass exists, there was a high degree of expectation there too. It's actually quite amazing to have so many of these recent discoveries, also be confirmations. It's been over a century of this, starting with Relativity.
Re:CERN experiment discovers five new particles by brutuscat on Tuesday March 21, 2017 @08:33AM (#13921578)
Professor Tim Gershon, Professor of Physics at University of Warwick and UK spokesperson for the LHCb experiment: “After the LHCb experiment is upgraded in the next long shutdown of the LHC (during 2019-20), it will be able to move to the next stage in the search for new particles: namely, doubly heavy baryons. These states – which contain two charm quarks or two beauty quarks or one of each – have long been predicted, but never yet observed. Their discovery will help to address important unsolved questions about how hadrons are bound together by the strong interaction.”

So I would assume that yes they have been predicted and is opening the doors for further confirmations?

Re:CERN experiment discovers five new particles by jessaustin on Tuesday March 21, 2017 @08:50AM (#13921680)
Please take more care in quoting. What you've quoted does not describe the current work, but rather something they haven't demonstrated yet called "doubly heavy baryons". That sentence was immediately preceded by this one:

Professor Tim Gershon, Professor of Physics at University of Warwick and UK spokesperson for the LHCb experiment, explained what will come next for the LHCb experiment: “After the LHCb experiment is upgraded in the next long shutdown of the LHC (during 2019-20), it will be able to move to the next stage in the search for new particles: namely, doubly heavy baryons.

Re:CERN experiment discovers five new particles by brutuscat on Tuesday March 21, 2017 @08:58AM (#13921743)
Yes, you are right, I miss read those paragraphs...
Re:CERN experiment discovers five new particles by greglindahl on Tuesday March 21, 2017 @03:16PM (#13925284)
Please mark when you make a significant edit of a comment that had a problem. Right now it looks like jessaustin's complaint is nonsensical.
Re:CERN experiment discovers five new particles by jessaustin on Tuesday March 21, 2017 @03:48PM (#13925540)
Haha like most of my complaints I think...
Re:CERN experiment discovers five new particles by wolfgke on Tuesday March 21, 2017 @08:42AM (#13921624)
> Their discovery will help to address important unsolved questions about how hadrons are bound together by the strong interaction.

If the particles were already predicted by the standard model, what kind of unsolved questions are to address here, besides validating the predictions of the standard model even further? (serious question)

Re:CERN experiment discovers five new particles by inlineint on Tuesday March 21, 2017 @09:50AM (#13922141)
The standard model provides a set of postulates that could be used for prediction of possible composite particles, their masses, and decay times.

However it is computationally infeasible to calculate them directly, without using various approximations. Physicists try to solve these problems numerically (see for example about the field called lattice QCD), but it is not always possible and leads to introducing various approximations that produce errors and other artifacts in the numerical predictions.

So the particles were allowed by the standard model, but we didn't know for sure their properties. So this provides way to verify already done numerical predictions (I don't really know were they be done for this exact particles or not) and give us data about exact properties of these particles.

One could possibly draw an analogy with (quantum) chemistry here.

Re:CERN experiment discovers five new particles by gus_massa on Tuesday March 21, 2017 @11:42AM (#13923202)
I'm not sure about this particular one, but a general idea is that the properties you are measuring in a particle depends on a lot of virtual particles.

It's difficult to find an easy example. After some searches in Google I found this unrelated example: http://www.strings.ph.qmul.ac.uk/~bigdraw/feynman/slide3.htm...

It has 9 Feynman diagrams. If you look at the top left diagram, there is an electron that enters from the bottom right corner, then it emits a photon that go out thought the top left corner, then the electron goes out through the top left corner.

The following two diagrams show the case were the electron emits a second (and third) photon and reabsorbs it, so the second (and third) photons are not visible for the experimenter, they are virtual photons. These additional photons are only important because the change slight the properties of the electron.

In the next three diagrams the photon is so strong that it can spontaneously split in another electron and a positron. It looks like a loop/circle, because positrons are like electrons traveling backward in time. They are virtual electrons, and again they are not visible in the lab, they are only important to make a tiny correction to the result of the experiment.

The other three diagrams have two virtual electrons, than makes even smaller corrections.

And in addition of the virtual electrons, there can be virtual muons and tauons. They are like electrons but with more mass. So the probability of having one of them is smaller, so the correction is smaller. In this case, I think that the correction is so small that it's impossible to measure it.

And you can have another virtual particles, like virtual quarks and virtual W, anything that has a charge. Moreover you can have virtual unknown particles (with charge) because nature doesn't care if we know the particle yet or not. But they are heavier, so the correction is negligible.

If you change the experiment, and for example make a electron collide with a positron, then the calculations are very similar, but there is more energy laying around, and the corrections from heavy particles are more important, so this variation is more useful to discover new particles.

Back to your question ...

The new particles are composed by three quarks, but actually they are composed by a lot of gluons and virtual quarks and antiquarks. To do any calculations you have to include a lot of diagrams like in the figure linked above, and a lot more, many many more.

IIRC the calculation is so complex that it's not possible to compare the experimental results with theoretical calculations. Perhaps they have some heuristic to compare the results with the results of similar particles.

This was probably part of a bigger experiment that produces a lot of particles, and they are trying to classify them in families. And perhaps in the classifications they can spot some strange pattern that may provide a hit that there is a new elementary particle.

Re:CERN experiment discovers five new particles by dukwon on Tuesday March 21, 2017 @10:12AM (#13922316)
Since QCD can't be calculated perturbatively at low energy, there are unsolved problems with how to get those predictions in the first place.
Re:CERN experiment discovers five new particles by binarymax on Tuesday March 21, 2017 @08:52AM (#13921695)
Because a prediction is just an assumption (theory), and it can become a house of cards when basing future science on that assumption. Observation is proof, so future science can use that proof without worry.
Re:CERN experiment discovers five new particles by nonbel on Tuesday March 21, 2017 @09:30AM (#13921965)
Can you clarify? In my mind

  "prediction" != "assumption" != "theory" 
and

  "observation" != "proof"
Basically I seem to disagree with everything you wrote.
Re:CERN experiment discovers five new particles by herpdorplarp on Tuesday March 21, 2017 @11:56AM (#13923365)
By assuming validity of a theory you can make predictions. Observations provide evidence in support of this.
Re:CERN experiment discovers five new particles by iamconfused on Tuesday March 21, 2017 @08:52PM (#13927690)
A theory comes later. You start off with a hypothesis. You don't make any assumptions of validity.
Re:CERN experiment discovers five new particles by iamconfused on Tuesday March 21, 2017 @08:44PM (#13927656)
This is my understanding.

You start with a hypothesis with no assumption of truth. Using that hypothesis you make a prediction and then use observation to test your prediction. During your observation you may find proof that your prediction was correct, which in turn provides support for your hypothesis. Once sufficient evidence is found for a hypothesis, it becomes a theory.

Re:CERN experiment discovers five new particles by nonbel on Wednesday March 22, 2017 @09:16AM (#13930613)
I'd say you have a theory from which you deduce a model that consists of various assumptions plus a hypothesis. If this hypothesis has not yet been compared to a set of observations, then it is also a prediction about that set of observations.

Also, the distinction between assumption and hypothesis is subjective, it depends what aspect of the phenomenon you care about at that time. Another term for assumption could be "auxiliary hypothesis".

Proof refers to the set of logical deductions (from theory + assumptions) that lead to the model, it has nothing to do with the observations.

Re:CERN experiment discovers five new particles by iamconfused on Wednesday March 22, 2017 @07:48PM (#13936208)
It's important not to confuse theory with scientific theory. They have very different meanings. In everyday speech a theory is roughly equivalent to a guess. In science, a theory is a well tested explanation of some phenomenon.

It's always hypothesis then theory. Your hypothesis may be based on other theories, but it is itself not a theory.

From Wikipedia: "The scientific method involves the proposal and testing of hypotheses, by deriving predictions from the hypotheses about the results of future experiments, then performing those experiments to see whether the predictions are valid. This provides evidence either for or against the hypothesis. When enough experimental results have been gathered in a particular area of inquiry, scientists may propose an explanatory framework that accounts for as many of these as possible. This explanation is also tested, and if it fulfills the necessary criteria (see above), then the explanation becomes a theory. This can take many years, as it can be difficult or complicated to gather sufficient evidence."

Re:CERN experiment discovers five new particles by grabcocque on Tuesday March 21, 2017 @09:39AM (#13922051)
There are a lot of baryons fyi:

https://en.wikipedia.org/wiki/List_of_baryons

Re:CERN experiment discovers five new particles by quakeguy on Tuesday March 21, 2017 @10:46AM (#13922597)
Math tells me there must be 216, no? 3 quarks make a baryon, there are 6 types of quarks, so 6^3? Idk if up up up baryons are allowed though, or any other baryon made of 3 equal quarks.
Re:CERN experiment discovers five new particles by filmor on Tuesday March 21, 2017 @10:57AM (#13922713)
They are allowed (https://en.wikipedia.org/wiki/Delta_baryon). Also, you need to take into account the overall spin of the particle (may be either 1/2 or 3/2 depending on whether the quark spins all have the same direction or not) and the individual spins of the constituents. Check https://en.wikipedia.org/wiki/List_of_baryons for details.
Re:CERN experiment discovers five new particles by whyever on Tuesday March 21, 2017 @04:39PM (#13926018)
You can also have excited particles that have the same quark content. They are called "resonances", are unstable and can decay. For example, the five particles discovered here are excitations of the particle containing two strange and one charm quark.
Re:CERN experiment discovers five new particles by pavel_lishin on Tuesday March 21, 2017 @11:48AM (#13923260)
Pentaquarks are also theorized to exist: https://en.wikipedia.org/wiki/Pentaquark
Re:CERN experiment discovers five new particles by guitarbill on Tuesday March 21, 2017 @09:05AM (#13921793)
AFAIK, the experimentally determined rest masses of these excited states/particles (same thing, different was of looking at it) agree with the calculated ones well. So yes, they were predicted. No surprises sadly; of course it's still a huge achievement!
Re:CERN experiment discovers five new particles by dukwon on Tuesday March 21, 2017 @10:14AM (#13922332)
The theory uncertainties are large. Any measurements within a broad range would also agree with some calculated masses. That doesn't tell you much.

See e.g. https://arxiv.org/abs/1311.4806

Re:CERN experiment discovers five new particles by gpderetta on Tuesday March 21, 2017 @08:30AM (#13921562)
yes, and note that these are not fundamental particles (like the Higgs was for example), but composite particles of yet another combination of the fundamental quarks. The SM predicts the existence of hundreds (thousands?) of these.
Re:CERN experiment discovers five new particles by inlineint on Tuesday March 21, 2017 @09:33AM (#13921989)
Actually it is even a one new particle (Omega_c baryon), but they observed five different excited energy states of it (like observing different excited states of a Hydrogen atom), so called resonances [1]. But the discovery is still exciting because it should have been really hard to find something that we don't really know how looks like in such large amount of noise.

The problem is that it is hard for us to predict masses/energies of new composite particles because although Standard Model provides hypothetical way to do it, it is infeasible computationally.

[1] http://physics.stackexchange.com/questions/64862/resonances-...

Re:CERN experiment discovers five new particles by nonbel on Tuesday March 21, 2017 @09:38AM (#13922045)
>"it should have been really hard to find something that we don't really know how looks like in such large amount of noise."

But if there are thousands of different such "surprising-to find-particles" to possibly detect, is it actually surprising to observe one of them?

Edit:

Also, from the top answer at your link: "The first generation of elementary particles are by observation not composite and therefore not seen to decay...The Standard Model of elementary particles, with the three generations of matter, gauge bosons in the fourth column and the Higgs boson in the fifth."

From wikipedia: "In the Standard Model, the Higgs particle is a boson with no spin, electric charge, or colour charge. It is also very unstable, decaying into other particles almost immediately." https://en.wikipedia.org/wiki/Higgs_boson

So do elementary particles decay or not?

Re:CERN experiment discovers five new particles by inlineint on Tuesday March 21, 2017 @09:57AM (#13922204)
> But if there are thousands of different such "surprising-to find-particles" to possibly detect, is it actually surprising to observe one of them?

It is hard to correctly identify what exactly particles from those possible thousands are observed in given data. The are two main problems: the properties of those not yet observed particles are not well known (because it is computationally hard to predict them from the standard model) and because the number of useful events is much much smaller than the number of events that correspond to already known events.

> So do elementary particles decay or not?

I don't see a contradiction here: the first generation of elementary particles does not decay (or has not been observed to decay yet), Higgs boson is not from then because the author of the answer are talking about the first generation of fermions and Higgs boson is not one of them.

Re:CERN experiment discovers five new particles by nonbel on Tuesday March 21, 2017 @10:12AM (#13922310)
Thanks, I missed that "first generation" detail.
Re:CERN experiment discovers five new particles by ajross on Tuesday March 21, 2017 @01:04PM (#13924086)
Yes. They're baryons (three-quark states). This is analogous to the discovery/synthesis of new isotopes in the middle of the last century. Technically they were "predicted", but it's still important to take the measurements. Occasionally there are surprises.