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Ten years after the Higgs, physicists face the nightmare of finding nothing else

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Re: Ten years after the Higgs, physicists face the nightmare of finding nothing else

#161

There is an existential angst amongst particle physicists because they all understand that they are the thoroughbred pets of the scientific world. Even if they find something, it doesn't matter, because they are working in energy regimes that are not reachable in the ordinary physics of the universe as it exists today. Even the discovery that the Higgs Boson as a lighter mass than predicted, while intellectually intr…

>because they are working in energy regimes that are not reachable in the ordinary physics of the universe as it exists today.

This isn't accurate. Actually because of the higher energies (> 10 orders of magnitude) naturally found throughout the universe one could argue to concentrate more on collecting data of those relatively ubiquitous events in the observable universe instead of going through the route in obtaining some little fractions of that energy on earth.

Current "records" [0]

>Fastest Fermilab proton: 980 GeV; 99.999954% the speed of light; 299,792,320 m/s.

Fastest LHC proton: 7 TeV; 99.999990% the speed of light; 299,792,455 m/s.

Fastest LEP electron (fastest terrestrial accelerator particle): 105 GeV; 99.9999999988% the speed of light; 299,792,457.9964 m/s.

Fastest cosmic ray proton: 5 × 10^10 GeV [!!!]; 99.999999999999999999973% the speed of light; 299,792,457.99999999999992 m/s.

[0]https://www.forbes.com/sites/startswithabang/2019/08/23/cosm...

Re: Ten years after the Higgs, physicists face the nightmare of finding nothing else

#162

Earlier quoted context omitted.

They haven't found nothing. They've found something, which is nothing. They've looked, been able to rule out some hypotheses of what they might find, and have established some evidence against others. Progress achieved, and the search continues.

The problem IS that they have found nothing. We know the Standard Model, as good as it is, is either incomplete or incorrect and without new physics somewhere we have no indication of how to fix it.

This "nothing" is valueable information nonetheless.

Science is just as much (often more) about ruling out hypotheses as it is about confirming them. Sometimes that means ruling out all existing hypotheses, meaning new ones have to be formulated to be tested in turn.

Re: Ten years after the Higgs, physicists face the nightmare of finding nothing else

#164
post #127

Earlier quoted context omitted.

> Have you had a good look? It's difficult to explain, but they[1] tried very hard. For example the electron has an electric charge but it's also like a small magnet. In an ideal elementary particle, the value of the magnet is 2 * something. In a real elementary particle the value is almost-2 * something, so they are measuring the almost-2, and it's call g [2]. For an electron, the measured value of g is 2.0023193043…

gus_massa: Since you are likely an expert, could you recommend a resource that explains how you use the Lagrangian equation for the standard model [1] to actually compute a predicted value for the electron's g ? An elementary resource that goes through basic steps for a computer scientist (non expert in QFT) would be a great. A simpler particle than electron is also ok, but I'd love to understand how you mess with th…

Sadly not an expert in that area. I only took a course of Nuclear Physics for a Major in Physics [1]. So I can read and understand that stuff, but the fine details pass over my head.

Looking at a recent page of that course, the recomended books are

* F. Halzen, A. Martin, “Quarks and Leptons: An introductory course in modern particle physics” (Wiley 1984)

* D. Griffiths, “Introduction to elementary particles” (Wiley 1987)

(and a few more)

The calculation for g=2 is quite easy (for an advanced Physics student). I remember the general idea, but not the details. I think I can reconstruct the details if necessary. It may be explainable in a blog post skipping some details.

The first correction g=2+1/137.036 is also humanly compresible, and can also be explained with some graphics. It would be very hard for me, but if I have a week to seach and rehearsal it is possible.

As the sibling comment says, the following corrections g=2+1/137.036+g=2+?/137.036^2 get harder and harder. And there are too many technical details and problems. I can only see the graphics and get a shallow understanding, but how they are transformed to integral and how to calculate all of them efficiently is too much for my knowledge.

[1] I never finished my Major in Physics, but I finished the one in Math.

Re: Ten years after the Higgs, physicists face the nightmare of finding nothing else

#165
post #120

"Science" doesn't care about individual careers or generations (in that case of physicists) who are left with "nothing else" to discover (fundamentally) and are simply "condemned" to pass the torch (determining values and uncertainties as best as possible). It's a brutal selection process if viewed from an individual lens which can consciously participate for say at best only 3 generations. The institutionalized syst…

There are more fundamental considerations to be made. For example, the small scale structures of the universe might just be too small to be observable by experimental means. As in, not just practically too small (too difficult to build experiments for it), but fundamentally not possible to observe due to their mathematical structure.

There are already a lot of things in quantum physics particularly that we can't observe directly. For example, there's no such thing as observing separate quarks - if you separate two quarks too much the binding energy between them pops another set of quarks into existence. But you can infer their existence indirectly "via math" basically.

However it's easily possible that the more fundamental structures of the universe are bound in such a way that you can't even observe them indirectly, even if you had access to machines that could produce the energies required.

Re: Ten years after the Higgs, physicists face the nightmare of finding nothing else

#166
post #46

Stagnation of scientific fields is normal and can last many years. In that time, little anomalies pile up, are swept under the rug, and largely forgotten. To admit anomalies can ruin careers, after all. Eventually someone (often very young/inexperienced) comes along and upends the field by proposing a different model or doing the experiment whose weight breaks the camels back. What's new here is the scale of the work…

How does finding an anomaly ruin a career? Any examples from particle physics?

Re: Ten years after the Higgs, physicists face the nightmare of finding nothing else

#168

Earlier quoted context omitted.

Space won't work for the kind of physics the LHC does. The fundamental problem is that collider physics relies on being able to create collisions of exactly known quantity as your input (eg in the LHC's case, proton-proton collisions at a 14TeV centre of mass energy). If you don't control the input, you can't extract any information about the output you detect, in the same way that you can't create a simulation of sn…

> Space won't work for the kind of physics the LHC does. https://home.cern/science/engineering/cryogenics-low-tempera... > The LHC's cryogenic system requires 40,000 leak-tight pipe seals, 40 MW of electricity – 10 times more than is needed to power a locomotive – and 120 tonnes of helium to keep the magnets at 1.9 K. Launch cost per kg aside for the detectors and basic framework, space is the best place for pushing…

All that stuff you're describing would still need to be sent to space, for no upside. That includes the 27km+ long collider ring. I haven't even mentioned the fact that this stuff is built 100 metres underground precisely to avoid noise from cosmic radiation.
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