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 Post Posted: Fri Apr 21, 2017 9:09 am 
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New (p)article … and the view of an advocate vs a realist:

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A few weeks ago, famed physicist (and supersymmetry-advocate) John Ellis asked the question, "Where is Particle Physics going?" Unless experiments can generate new, unexpected results, the answer is likely to be "nowhere new; nowhere good" for the indefinite future. - https://www.forbes.com/sites/startswithabang/2017/04/20/new-lhc-results-hint-at-new-physics-but-are-we-crying-wolf/#6b5883984273

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 Post Posted: Sat Apr 22, 2017 1:24 am 
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Ethan Siegel completely misses the point. No one would care about the most recent measurement if it would be on its own. But we have something like 10 measurements of b->s mu mu coupling, and they all show a deviation in the same direction. A lower number of muons than expected in the low q range, and with a different than expected angular distribution. The combined significance is much larger than the significance of the individual measurements.

I summarized the more recent measurements here, but there are also older measurements from the B-factories showing a similar trend.

With the 2015 and 2016 data recorded already, we should know more in about a year.


A technical error in the article:
Quote:
But a closer inspection of the latest data shows that the statistical significance is only about 2.4 and 2.5 sigma, respectively, at the two energies measured. This is about a 1.5% chance of a fluke individually, or about 3.7-sigma significance (0.023% chance of a fluke) combined
I have no idea how he gets 3.7 sigma. Even with 100% uncorrelated systematics and with the theory predictions that give the largest discrepancies we only get sqrt(2.4^2 + 2.5^2) = 3.5 sigma. But the systematics are correlated, leading to a lower significance.


John Ellis answers his own question, by the way:
Quote:
Where is Particle Physics Going?

The answer to the question in the title is: in search of new physics beyond the Standard Model, for which there are many motivations, including the likely instability of the electroweak vacuum, dark matter, the origin of matter, the masses of neutrinos, the naturalness of the hierarchy of mass scales, cosmological inflation and the search for quantum gravity. So far, however, there are no clear indications about the theoretical solutions to these problems, nor the experimental strategies to resolve them. It makes sense now to prepare various projects for possible future accelerators, so as to be ready for decisions when the physics outlook becomes clearer. Paraphrasing George Harrison, "If you don't yet know where you're going, any road may take you there."


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 Post Posted: Sat Apr 22, 2017 7:41 am 
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The combined significance is much larger than the significance of the individual measurements.

The struggle to squeeze one last drop out of the experiment.

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 Post Posted: Fri Apr 28, 2017 10:13 am 
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No, the proper way to do science.


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 Post Posted: Fri Apr 28, 2017 11:41 am 
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mfb wrote:
No, the proper way to do science.

Oh man, you can buy at Amazon a Cloud Chamber kit for $38 that has more energy than the particle-collisions at the LHC: https://www.amazon.com/CL-Cloud-Chamber-Kit/dp/B0168SCCJO

The standard model was build with what we got out of those already in the 1960's, the Higgs boson was added as last particle in '67 … that's freaking 50 years ago … since than we made no progress with these kinds of experiments. But if you like to think that you are doing 'proper science' and not just collecting dust of an old experiment than go ahead … it is only yourself who you are fooling. :mrgreen:

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 Post Posted: Fri Apr 28, 2017 3:53 pm 
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mfb, why do you feed the troll? It's a lost cause.


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 Post Posted: Fri Apr 28, 2017 4:12 pm 
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dukwon wrote:
mfb, why do you feed the troll? It's a lost cause.

Oh, but I am not a troll, I am more like that little voice in your head asking the question is it actually meaningful what I am working on, or should I perhaps do something more useful with my precious time here on this wonderful planet Earth.

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 Post Posted: Sat Apr 29, 2017 3:03 pm 
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If you hear little voices in your head, you should seek professional help.

If you don't see the purpose of the LHC, just go to other forums?


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 Post Posted: Sat Apr 29, 2017 3:26 pm 
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mfb wrote:
If you hear little voices in your head, you should seek professional help.

No need to get help when you have a 'concience'.

conscience
ˈkɒnʃ(ə)ns/
noun
a person's moral sense of right and wrong, viewed as acting as a guide to one's behaviour.
"he had a guilty conscience about his desires"
synonyms: sense of right and wrong, sense of right, moral sense, still small voice, inner voice, voice within; …

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If you don't see the purpose of the LHC, just go to other forums?

I do see the purpose, but I don't see it in the same light as you do.

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 Post Posted: Mon May 08, 2017 7:22 pm 
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Everything good here guys? :thumbup:

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