5 ms·

I'm not much of a particles guy but isn't the lack of "expected" discoveries itself a discovery?

refulgentis 1y ago
You nailed it. In addition, they're absolutely correct, some subset of particle researchers were wish-casting for SUSY stuff. In addition, there's a significant substantive difference between "$X was defined and built for discovering $Y" and "some subset of $X hoped for proof of their theory $Y via $Z being discovered" -- there was also some subset that hoped for proof of string theory, or innumerable other things. In general they're right and know their stuff if they're able to have this detailed of a take, but the actual claim "The word "expected" is doing a lot of work.", is doing a lot of work. And I was there. In a graduate physics lab with multiple faculty members on the LHC before it opened, including a big SUSY fan who thought that'd be a bank shot on a bank shot outcome, maybe. Hoped for by some? Yes. Expected by a majority? Absolutely not.
- MadnessASAP 1y ago
  Neat! Thanks for sharing your insight and fancy words :)
- T-A 1y ago
  Experimenters always were more skeptical; I hypothesized asking phenomenologists for a reason. I like Adam Falkowski's description of what it was like in [1] (about the end of dedicated SUSY working groups at CERN): the existence of SUSY was almost a fact for a bulk of researchers working on the topic. This certainly was reflected in hiring practices, and you had a large group of top researchers whose entire publication list was tied to supersymmetry [1] https://www.scientificamerican.com/article/supersymmetrys-long-fall-from-grace/ https://www.scientificamerican.com/article/supersymmetrys-lo...
  - refulgentis 1y ago
    I don't disagree but you choosing contrarianism to show you're clever and know a lot here (which worked!) made it sound like CERN was expecting a SUSY particle or whatever (which it wasn't)
    - T-A 1y ago
      > you choosing contrarianism ? > to show you're clever and know a lot ?!? I contribute to discussions when I have the time and think I have something relevant to say. HN is hardly the right place to show off about physics, and trying to do so anonymously would be particularly pointless. > made it sound like CERN was expecting a SUSY particle That's not what I wrote. My point was explicitly about expectations on the theory side. Perplexed.
Ygg2 1y ago
It invalidated some flavors of string theory, but my understanding is that you have almost infinite numbers of free params you can tweak. In other words super symmetry wasn't excluded, just excluded for XeV where X is what LHC is able to produce.
jerf 1y ago
Yes, but it's a weak one. One of the problems we have is that we are generally inculcated by our educational system to just think "science is good", without asking how good. But when we're talking about things like massive supercolliders, which cost things that start looking less like "a grant from the National Science Foundation" and more like "the entire economic output of a small country for a couple of decades", we need to ask whether we're getting enough science bang for our science buck, because not even science is actually immune to that question. The LHC is honestly pretty questionable on that front. One can debate what was expected, but what is perhaps easier to wrap your mind around is certainly the LHC would have been immensely more valuable if it had found all sorts of supersymmetric particles, right? Personally I think the most potent criticism of building yet another, even larger collider is just that such a collider requires essentially strangling the entire rest of the field for decades on end, and indeed, at this level of expense, strangling neighboring fields for decades on end, to fund something that doesn't have a terribly clear through-line on its value, on any dimension, practical or purely scientific. It's almost like "let's build a larger collider" is just a reflex at this point. There's a lot of interesting things bubbling on the fringe right now, and I don't mean the crazy fringe, I mean the scientific fringe. Maybe we should take a bit of a break from particle colliders for a bit and put some money into those things for a while. We don't have infinite money, and we don't have guaranteed money; pouring vast, vast quantities of money into a new collider could well inhibit future research monies. It is still important to think about not whether we "should" spend the money in this or that way, because that always produces more "yes" answers than we actually have money for. The question is, is this the best way to spend money? And given the staggering amount we're talking, it's a high bar for this to be "best". Personally I'd really rather see at least a decade or so of just spreading things around a bit more, rather than pouring all of that into what is essentially a single project.
- parineum 1y ago
  Additionally, while you're talking about budget in a practical manner, spending money on science to discover science isn't something that people outside of science generally love spending money on. I am nearly certain that part of the hope for people spending that kind of money on the LHC is not only might they discover something amazing but that it might also be practically useful to someone else. There are other scientific fields that produce much more tangible results that the finite funding could go to. Even something like materials science which could not only produce more useful discoveries but could also make the next collider cheaper.
tsimionescu 1y ago
Only if you have a finite set of theories. If you have infinitely many theories that could explain a phenomenon, eliminating some swath of them brings you 0 new information, in information theoretical terms. The problem with SUSY and String theory and other similar physical theories is that they have many free parameters that can have any value that hasn't yet been ruled out by experiment. So if you build a collider twice as large and find nothing, you'll find that your parameter that today has possible range [n, +Inf) will now be known to have range [2n, +Inf). That doesn't actually mean anything at all, though. That doesn't actually tell you anything: you'll need infinitely more experiments to know what's the value of that parameter.

You nailed it. In addition, they're absolutely correct, some subset of particle researchers were wish-casting for SUSY stuff. In addition, there's a significant substantive difference between "$X was defined and built for discovering $Y" and "some subset of $X hoped for proof of their theory $Y via $Z being discovered" -- there was also some subset that hoped for proof of string theory, or innumerable other things. In general they're right and know their stuff if they're able to have this detailed of a take, but the actual claim "The word "expected" is doing a lot of work.", is doing a lot of work. And I was there. In a graduate physics lab with multiple faculty members on the LHC before it opened, including a big SUSY fan who thought that'd be a bank shot on a bank shot outcome, maybe. Hoped for by some? Yes. Expected by a majority? Absolutely not.

MadnessASAP 1y ago
Neat! Thanks for sharing your insight and fancy words :)
T-A 1y ago
Experimenters always were more skeptical; I hypothesized asking phenomenologists for a reason. I like Adam Falkowski's description of what it was like in [1] (about the end of dedicated SUSY working groups at CERN): the existence of SUSY was almost a fact for a bulk of researchers working on the topic. This certainly was reflected in hiring practices, and you had a large group of top researchers whose entire publication list was tied to supersymmetry [1] https://www.scientificamerican.com/article/supersymmetrys-long-fall-from-grace/ https://www.scientificamerican.com/article/supersymmetrys-lo...
- refulgentis 1y ago
  I don't disagree but you choosing contrarianism to show you're clever and know a lot here (which worked!) made it sound like CERN was expecting a SUSY particle or whatever (which it wasn't)
  - T-A 1y ago
    > you choosing contrarianism ? > to show you're clever and know a lot ?!? I contribute to discussions when I have the time and think I have something relevant to say. HN is hardly the right place to show off about physics, and trying to do so anonymously would be particularly pointless. > made it sound like CERN was expecting a SUSY particle That's not what I wrote. My point was explicitly about expectations on the theory side. Perplexed.

Ygg2 1y ago

It invalidated some flavors of string theory, but my understanding is that you have almost infinite numbers of free params you can tweak. In other words super symmetry wasn't excluded, just excluded for XeV where X is what LHC is able to produce.

jerf 1y ago

Yes, but it's a weak one. One of the problems we have is that we are generally inculcated by our educational system to just think "science is good", without asking how good. But when we're talking about things like massive supercolliders, which cost things that start looking less like "a grant from the National Science Foundation" and more like "the entire economic output of a small country for a couple of decades", we need to ask whether we're getting enough science bang for our science buck, because not even science is actually immune to that question. The LHC is honestly pretty questionable on that front. One can debate what was expected, but what is perhaps easier to wrap your mind around is certainly the LHC would have been immensely more valuable if it had found all sorts of supersymmetric particles, right? Personally I think the most potent criticism of building yet another, even larger collider is just that such a collider requires essentially strangling the entire rest of the field for decades on end, and indeed, at this level of expense, strangling neighboring fields for decades on end, to fund something that doesn't have a terribly clear through-line on its value, on any dimension, practical or purely scientific. It's almost like "let's build a larger collider" is just a reflex at this point. There's a lot of interesting things bubbling on the fringe right now, and I don't mean the crazy fringe, I mean the scientific fringe. Maybe we should take a bit of a break from particle colliders for a bit and put some money into those things for a while. We don't have infinite money, and we don't have guaranteed money; pouring vast, vast quantities of money into a new collider could well inhibit future research monies. It is still important to think about not whether we "should" spend the money in this or that way, because that always produces more "yes" answers than we actually have money for. The question is, is this the best way to spend money? And given the staggering amount we're talking, it's a high bar for this to be "best". Personally I'd really rather see at least a decade or so of just spreading things around a bit more, rather than pouring all of that into what is essentially a single project.

parineum 1y ago
Additionally, while you're talking about budget in a practical manner, spending money on science to discover science isn't something that people outside of science generally love spending money on. I am nearly certain that part of the hope for people spending that kind of money on the LHC is not only might they discover something amazing but that it might also be practically useful to someone else. There are other scientific fields that produce much more tangible results that the finite funding could go to. Even something like materials science which could not only produce more useful discoveries but could also make the next collider cheaper.

tsimionescu 1y ago

Only if you have a finite set of theories. If you have infinitely many theories that could explain a phenomenon, eliminating some swath of them brings you 0 new information, in information theoretical terms. The problem with SUSY and String theory and other similar physical theories is that they have many free parameters that can have any value that hasn't yet been ruled out by experiment. So if you build a collider twice as large and find nothing, you'll find that your parameter that today has possible range [n, +Inf) will now be known to have range [2n, +Inf). That doesn't actually mean anything at all, though. That doesn't actually tell you anything: you'll need infinitely more experiments to know what's the value of that parameter.