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Particle Physicists Continue to Make Empty Promises

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Re: Particle Physicists Continue to Make Empty Promises

#111

Post by mnl »

sgt101 wrote: post #100
mnl wrote: post #73

Earlier quoted context omitted.

That's the Hossenfelder take on the scientific method for you: whereby you make the experiments to confirm the theory. Which is fantastic because if science had ever worked that way you would be done with all experiments as the sensible ones would give known results, so what's the point.

The point is that you can spend a lump of money to check things out in that way, and fine - especially when you have the Higgs to confirm as well. But if you want to double down you need to have better evidence and a better argument. This is the logic that applies in any lab; sure take a punt look at x or y, if you're right then you'll get a grant and your career will thrive. If you're wrong you're out. That's happen…

The thing is we didn't know whether the mechanism of electroweak symmetry breaking involved the Higgs or something else. But we knew that there would be particles associated to electroweak symmetry breaking at TeV scale because of a unitarity bound, among other reasons (as happens with this particular kind of dark matter at 100 TeV that Sabine dishonestly calls "weasel words").

Something had to happen at that scale, the Higgs wasn't guaranteed. Sabine gets experimental physics backwards because no one planned the LHC to confirm the Higgs, but to know whether the Higgs existed and if it didn't what did instead. My money was mostly on it not showing up; many physicists were convinced it wouldn't, then it was there but we couldn't know beforehand.

There's a scientific case for making precision measurements of it, as was done with the electroweak bosons for very good reasons that she dismisses without showing any kind of understanding about the research she wants to shut off.

Re: Particle Physicists Continue to Make Empty Promises

#112

Post by SiempreViernes »

TheOtherHobbes wrote: post #91
Joker_vD wrote: post #80

Earlier quoted context omitted.

> ROI = (the potential advance) / (invested money) is too small That's unknown in advance. To take example from maths, the conic sections, braid theory, number theory—they all used to be very abstract and un-applicable parts maths, until one day.

If it's unknown in advance surely it's more rational to spread the research out instead of putting most of the available eggs in a single basket. CERN found Higgs - which was proposed decades before CERN was built. There is nothing like the Higgs proposal around today. That's the real problem. Spend $20bn on some new models, and then you can spend $20bn chasing the most interesting prospects. That's far more likely t…

> Spend $20bn on some new models, and then you can spend $20bn chasing the most interesting prospects.

This is a very incorrect description of the problem. The situation in basic particle physics is that models are super plentiful; Six months in 2016 saw 500 different papers written to explain a novel signal that ended up not being real, so it's not models that are missing.

Re: Particle Physicists Continue to Make Empty Promises

#113

Post by SiempreViernes »

sgt101 wrote: post #95
orbifold wrote: post #29

Earlier quoted context omitted.

Building a high energy collider is like building a larger telescope. The only things you can be sure of is that you will be able to understand whatever you have seen better than before. There is scientific consensus that we should be able to understand dark matter better by building one aswell. This is supported by technical arguments which are hard to communicate to the general public. Attacking this communication t…

>>There is scientific consensus Really - I thought that we were debating an article by a scientist, who along with many other scientists disagrees with that position. >>This is supported by technical arguments which are hard to communicate to the general public. And yet the general public is being asked to pay for it. Perhaps sorting out that gap and explaining how understanding dark matter will be as important as (f…

Well, it's a scientist in a different field. More importantly, it's by a scientists that doesn't engage with the technical arguments made by those actually in the field, so it's unclear what exactly the label "scientist" brings.

If a physicist criticises recommendations by epidemiologist without reference to the theory of how diseases spread, should you count that as disagreement from the consensus of how to fight infectious diseases?

Re: Particle Physicists Continue to Make Empty Promises

#114

Post by iainmerrick »

matthewdgreen wrote: post #98
iainmerrick wrote: post #31

Earlier quoted context omitted.

I think you’re setting up a bit of a straw man there. I agree that people coming up with creative ideas and making bold predictions is good in general. But surely we’re allowed to point out when a) predictions have not in fact worked out, and b) nothing particularly useful was learned from the failure. That’s not the same as trying to discourage new ideas. For the LHC specifically, it was widely expected that it woul…

This appears to value the negative findings of the LHC at zero. I’m no physicist, but my understanding is that some variants and parameters of the theory have been excluded as a result of LHC experiments. More to the point, what is the alternative strategy that’s more likely to produce useful data? “Don’t do experiments to validate or invalidate theory” doesn’t obviously seem like it’s going to produce better results…

I’m no physicist, but my understanding is that some variants and parameters of the theory have been excluded as a result of LHC experiments.

I'm no physicist either, so take my hot take with the appropriate pinch of salt. :) My understanding is that some variants and parameters should have been excluded, if you hold theorists to their ~2005 predictions, but in practice most theorists are essentially burying their heads in the sand, or ignoring their past predictions and just making new ones. Both Hossenfelder and Peter Woit (of the "Not Even Wrong" book and blog) have documented many such cases. Many theorists are still assuming supersymmetry as a basis for their work and essentially ignoring the fact that it didn't show up where expected.

More to the point, what is the alternative strategy that’s more likely to produce useful data?

I think it's "remove the focus from high-energy physics and particle colliders, bring more attention to less fashionable areas that might benefit more from huge big-budget experiments." I don't know of any specific proposals to do something completely different with the budget that might otherwise go to e.g. CERN's Future Circular Collider proposal. Hossenfelder has pointed to other big science projects that could produce more scientific bang-for-the-buck than the LHC, such as LIGO and the James Webb space telescope.

Re: Particle Physicists Continue to Make Empty Promises

#115

Post by beezle »

pmontra wrote: post #33
aroberge wrote: post #5

Dr. Sabine Hossenfelder is an opiniated physicist who gets a lot of flak for constantly commenting on this issue. Yet, I believe she does society a service in doing so. I have yet to see anyone contradict her basic premise with factual information. I wish she were wrong, as I would love to see a breakthrough towards an experimentally verified Grand Unified Theory, including an explanation for what we currently identi…

It's hard to be loved when one wants to take money away from other people and their projects. A more promising line of action would be building another community of particle physicists with different goals than building a bigger collider, possibly aligned with Hossenfelder's suggestions. In this way they'll have something to gain and will fight for the budget that otherwise would go into the collider.

You mean like RHIC and JLAB? They had to compete mightily over comparative trump change for an upgrade to an electron-ion collider? (RHIC won but JLAB will contribute)

There are plenty of other areas of real research that are still nominally 'particle' physics that are actually able to put to paper real goals for what they expect to achieve.

There are also facilities like NSLS II that are heavily subscribed and doing research that is both very real world and pie in the sky.

Keep this in mind too - the Tevatron at FNAL would have had the Higgs discovery if they could have run another 3-5 years - they already had data order 3 sigma IIRC. Likewise, they would have had a lot more data on the top, something LHC has been gathering since the confirmation of the Higgs. This would have come at a fraction of the cost of the Higgs. Beyond that, has Higgs done anything more than add to the already known to be narrow avenues left for SUSY?

She is absolutely correct that the particle physics community needs their feet held to the fire to justify such an enormous single outlay and being a jobs program for a few thousand physicists is not one of them.

Re: Particle Physicists Continue to Make Empty Promises

#116

Post by aaron695 »

nxpnsv wrote: post #45

I don't agree with her initial gripe. Discovery or serious exclusion - it is not weasel words, it is the truth. The correct question to ask is if the exclusion would be enough to warrant the cost. And of course this is far from the only result one would expect from such a machine. So these are not empty promises and while she clearly is not stupid, Hossenfelder sure loves telling people their research is useless... E…

> "Discovery or serious exclusion - it is not weasel words, it is the truth."

This misrepresents what she says about weasel words.

Also she specifically addresses the "Discovery or serious exclusion"

I didn't downvote but I would guess you've only skimmed the written article, try watching the video.

Re: Particle Physicists Continue to Make Empty Promises

#117

Post by SiempreViernes »

tsimionescu wrote: post #101
Joker_vD wrote: post #80

Earlier quoted context omitted.

> ROI = (the potential advance) / (invested money) is too small That's unknown in advance. To take example from maths, the conic sections, braid theory, number theory—they all used to be very abstract and un-applicable parts maths, until one day.

Professor Hossenfelder and others have written long books about why the probability of finding new physics based on not liking the aesthetics of the current maths (naturalness, supersimetry, grand unification) is extremely likely to fail, and has been constantly failing for ~50 years. If our way of generating new theories has given bad predictions for 50 years, at what time should we stop and try out other ways of ex…

They make qualitative arguments, nobody has any realistic prediction of what the probabilities are.

And the problem has never been making new theories, the problem is always that we have a very good model, and no principled way for choosing between all the possible theories that gives rise to almost precisely that model.

So people tried to invent reasons and so far nobody has had any luck. And Hossenfelder is correct that in hindsight naturalness wasn't a very good rule.

But by the same hindsight, no theory that could be detected in previous experiments would have worked either. In this view, making the experiments at all was a complete waste, we should just have drawn the winning theory from a hat and stopped all further work.

Re: Particle Physicists Continue to Make Empty Promises

#118

Post by SiempreViernes »

nabla9 wrote: post #109
orbifold wrote: post #97

Earlier quoted context omitted.

BTW her examples of experiments that received insufficient funding is really curious: FAIR she just happens to work at a university that is pretty directly involved with it, the cost overruns were so bad that the original people lost management of the project . The James Webb Telescope was in part delayed because it shares the platform with the next gen of American spy sattelites. I happen to know someone that worked…

Her main point is that from physics perspective there are better ways to use money. Whatever success and failures in projects, we should keep throwing money into places that are more likely solve important physical questions. Any argument that sidesteps that is nonsense. If goal of investing in fundamental physics is not R&D it's just a side effect as I assume. If I read your argument correctly it's "We can't give ar…

The particle community has enumerated why new accelerators are the best way to answer particle physics questions, Hossenfelders position is however that those arguments aren't worth engaging with because particle physicists are slaves to "group think".

As for the argument that cosmology or astronomy are more promising ways of yielding new insights, that's not something she ever bothers to discuss in detail. There's no articles about how the extremely noisy and uncertain constrains from astronomy are more worth to gamble on that than the much cleaner direct detections from accelerators.

And there's certainly no arguments about how we should stop giving so much money to the exoplanet researchers and their instruments instead of making satellites to measure the cosmic radio background. (There's not even a little post about how SpaceX will hamper radio astronomy by making sure there's no radio quiet place left on earth).

Re: Particle Physicists Continue to Make Empty Promises

#119

Post by gus_massa »

sgt101 wrote: post #95
orbifold wrote: post #29

Earlier quoted context omitted.

Building a high energy collider is like building a larger telescope. The only things you can be sure of is that you will be able to understand whatever you have seen better than before. There is scientific consensus that we should be able to understand dark matter better by building one aswell. This is supported by technical arguments which are hard to communicate to the general public. Attacking this communication t…

>>There is scientific consensus Really - I thought that we were debating an article by a scientist, who along with many other scientists disagrees with that position. >>This is supported by technical arguments which are hard to communicate to the general public. And yet the general public is being asked to pay for it. Perhaps sorting out that gap and explaining how understanding dark matter will be as important as (f…

> Will understanding dark matter prevent the collapse of our planet and the deaths of our children?

It's difficult to know. General relativity is useful for GPS. Superconductivity is useful for NMR that actually sometimes saves children from cancer. Neither of the applications were clear at the discovery time.

(My favorite was Magnetoresistance. You start to explain it as a weird quantum boring effect of the spin of electrons in magnetic conductors, and when the other person is convinced that it totally unuseful you explain that it is used in hard disks. SSD are killing the fun.)

Re: Particle Physicists Continue to Make Empty Promises

#120

Post by SiempreViernes »

bnlpa wrote: post #34
orbifold wrote: post #9

Science shouldn’t be a zero sum game. As a physicist I love that we get a huge chunk of science funding for all kinds of stuff. Generally speaking developing a new accelerator leads to excellent technical advances at all levels of the stack. Web browsers and HTML were invented at CERN. Super conducting magnets at scale were pioneered for LHC. The detectors with custom radiation hard ASICs for particle detection and t…

I think it is wrong to cherry pick the HTML example. It would have been invented outside (wasn't SGML already a thing?). Compared to open source in general the CERN stacks are horrible, typical sloppy academic software of no use to the general public. Tons of stuff like the cling C++ interpreter that look interesting but are never polished to be generally useful.

Depends on who you ask I guess, present value of root has been estimated[1] at around 2.8 billion Euro.

[1]: https://www.youtube.com/watch?v=0Zpeh9wuzMs&feature=youtu.be...

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