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Whenever I see headlines like this, I'm reminded that physics has a communication problem where the public thinks that high energy physics is the only type (or

• AnimalMuppet 6y ago
  Heh. Tell them that their field should be moved to the theology department.
• ganzuul 6y ago
  It's almost as if they are saying that their 'real physics' isn't science, because in real science observation is first and foremost. I'm really looking forward to what XFEL can do for material science. Perhaps we can finally replace plastics with something like eutectic systems, bulk metallic glass, or the classic transparent aluminum.
  • akvadrako 6y ago
    Actually in real science theory is first, observation comes later as a way to judge competing theories. This is because all observations are theory-laden. They don’t tell you anything without a framework to interpret them in.
    • Learning2-2 6y ago
      Isn't this an idealization myth of the scientific method? I'm pretty sure some kind of observation prior to forming the theory will account for many theories.
      • __Joker 6y ago
        True that. It is like cat and mouse. You present a theory and validation and usefulness will come from experimental verification. And some theory comes from unexplainable observations. Michelson–Morley experiment and special theory of relativity will be taking the second path.
    • BlueTemplar 6y ago
      In a lot of situations, the observation is that the current favorite theory doesn't work for some observation, but the new theory explaining it only comes much later.
    • ganzuul 6y ago
      I disagree because we don't entertain theories which make no testable predictions. It seems logical that this rule makes observation the ultimate qualifier.
  • BlueTemplar 6y ago
    Yeah, as long as there's no experimental confirmation, it's metaphysics, which is a sub-branch of philosophy, not science. (And it doesn't matter how refined their mathematics are...)
• jiggawatts 6y ago
  I feel like modern high-energy physics as exemplified by CERN is a bit like NASA's Space Shuttle program: its main job is to hoover up all available money to fund the bureaucracy. Science outcomes aren't even a secondary goal, or a tertiary goal. They're waaaaaay down the list. Similarly, ITER is going to suck up a hundred billion in science funding that could have gone into a hundred $1B programs intsead of one giant one.
  • djaque 6y ago
    Yes, I have a friend who left plasma physics and is still salty about the situation with ITER. She also said that by the time they're done, the technology is going to be outdated since it all began in the 80's. I'd disagree that they are there to pump money into administrators. Some of these problems are just really hard and requires monstrously large organizations to make headway. At worst, I'd say that they are misguided/focusing on the wrong scientific questions or in the case of ITER stuck on a path that should have been abandoned a while ago.
    • willis936 6y ago
      If you have the chance, ask her what a better vision of the use of funding would be. Keep in mind that the physics goals are to test high neutron flux divertors, tokamak scaling laws, and burning plasma regime stability.
      • pantalaimon 6y ago
        AFAIK you can’t operate a tokamak continuously, only pulsed. A stellarator like Wendelstein 7-X looks like a much more promising design.
        • willis936 6y ago
          I know. I work at the first MHD optimized stellarator :) That doesn’t mean backing out of ITER 15 years ago would have been a good idea. It would be an even worse idea to back out of it now.
• Koshkin 6y ago
  So... why is the XFEL not “just” an achievement in engineering? Is there a (new) physics somewhere in it? (Genuinely curious.)
  • djaque 6y ago
    I forget who said it, but there is a quote in physics along the lines of "we already have a theory of practically everything, but it is so complicated that we can use it to predict almost nothing." All of basic principles that underlie our everyday experiences don't need quarks and gluons. They're governed by standard quantum mechanics which was fleshed out in the 20's. However, just because we have Newton's laws of the subatomic world doesn't mean we can answer interesting scientific questions with them. I'd even say that people that call something like the standard model a "theory of everything" are a little naive since you can never use to it make predictions outside of the most simple systems. That area (pushing ahead away from model systems) is the complexity frontier of physics and is where I'm most excited for advancements. It's where we can write out the equation that describes high-TC superconductors, but it has so many dimensions that we can't solve it and make one that works at room temperature. Is that engineering or physics? I'd call the scientific problem of figuring out the laws that emerge from quantum mechanics for these complicated systems physics. In a similar vein, Maxwell "discovered" the free electron laser in the 1800s. He wrote down the laws of E&M and then everything in the world was solved. That's clearly a dumb way to think of it though, and the new physics that was discovered were the emergent laws that fall out of it when you apply those laws to a system of relativistic particles. In particular, the emergent phenomena that had to be discovered for the free electron laser (FEL) was the micro-bunching instability. It's a subtle interaction between relativistic particles and a field of photons that will feedback and cause them to bunch together while dumping their energy into the field of light producing the coherent laser radiation. It was that phenomena and the realization that it could be used to create a powerful laser that are the new physics here. On the other side, the advancement of the FEL to the point that it could make x-rays requires a lot of other new physics to create the machine. This is where there is a bit of a blurred line between physics and engineering. However, I'd still call what we're doing (developing new laws of physics that govern complex systems) physics. Just because we use them to build a machine doesn't make them engineering any more than a solid state physicist discovering a new phenomena in semiconductors and then Intel taking advantage of it in their next generation of processors. In order to REALLY understand our physical world, we can't write down reductionist laws and say that we're done. It's also notable that the two developers of the free electron laser are rumored to be in the running for the Nobel prize in physics, so it's not just me who thinks that they are physicists, not engineers. Edit: BTW, here is a great paper that reviews the physics that makes a free electron laser work if anyone is interested. Huang, Z., & Kim, K.-J. (2007). Review of x-ray free-electron laser theory. Physical Review Special Topics - Accelerators and Beams, 10(3), 034801. https://doi.org/10.1103/PhysRevSTAB.10.034801 https://doi.org/10.1103/PhysRevSTAB.10.034801
• COGlory 6y ago
  My understanding as an x-ray crystallographer and electron microscopist is that XFEL has been nothing short of a massive disappointment. Yes, it works in theory, but in practice it's entirely inefficient and doesn't address the current bottlenecks of structural biology at all. I'm not saying this to downplay the project (I know very little about it) but the reception among those in the field it's supposedly applicable for has been underwhelming.
  • djaque 6y ago
    I'm not really sure about crystallography (not my field), but I think it's maybe an issue with expectation management. Everyone is trying to sell the new technology as fix for every field. In reality XFEL experiments do have a lot of overhead associated with them and stuff like synchrotron light sources are probably better suited for "everyday" type measurements. The real breakthroughs that I was talking about are for time resolved and "diffract before destroy" experiments for delicate samples. Those ones can't really be done at a synchrotron with long bunches. I'm especially excited for femtosecond time resolved measurements of chemical reactions. It's going to be so cool to watch chemical reactions occur at an atomic scale. I guess the other cool application is that there is so much light that you can perform diffraction off of single molecules when you want your sample in solution/gas phase or can't form crystals. Correct me if I'm wrong, but my impression was that the intensity of XFELs also enabled that.
    • COGlory 6y ago
      I didn't know about the time resolved stuff, and thats the type of thing that big expensive projects seem much more economical for. Presumably we will learn foundational (previously theoretical) information which will have wide, lasting effects. The project is so staggeringly complicated that when I've talked to people involved, they knew very little outside of their own minor field (for instance, microfluidics to time droplets with pulses). The way that the project is being sold from the structural side is that you won't need a crystal, which is obviously huge. However, there's the issue of scale, and also the classic issue of... We can't refocus diffracted X rays so we're still limited by protein we can express in a selenium doped media, since you need the selenium signal to determine phase data from the diffractions. The list of proteins that are soluble but won't crystallize/can't be resolved by Cryo-EM is pretty small, and so it's an incremental upgrade no one will have access to, at best. At least, from the structural side.
• konjin 6y ago
  > I feel that this also gets at a sort of toxic notion that I've noticed some high energy physicists in my own department have (not all, but you probably know the people that I'm talking about). The notion is that if you aren't working on 12 dimensional quantum theories of gravity or the holographic principle and black hole physics, then you aren't a real physicist. Somehow they think that if your work has a real world impact, then it's tainted in some way. I'm not sure how it's gotten this way, but I've actually been told as much by another grad student that my field should be moved to the engineering department because we aren't doing real physics. I got told that by a professor when I was looking at PhD options, I ended up in the maths department physics group because it was much nicer. It's an odd kind of self selection. People who aren't there to feel smart don't sign up for the course so high energy theoretical physics gets ever more filled with insufferable assholes. Not to say that the whole group was, but while every other group had the one token dickhead everyone avoided it seemed that the high energy theoretical group was run by them and the non-dickheads in the group were barely tolerated and mainly there to boost citations.
  • Certhas 6y ago
    I like to ask the following question: What do we know about reality that we didn't know before the work of these HEP theorists? This is not rhetorical. There are some works for which there is a concrete positive answer (which might not be simple). But there is much more for which the answer is simply nothing. I left the field years ago because it was clear that most of the work being done is not physics.
    • jsmcgd 6y ago
      What work were they doing?
• bsder 6y ago
  > I'm not sure how it's gotten this way, but I've actually been told as much by another grad student that my field should be moved to the engineering department because we aren't doing real physics. That's a touch unkind of your friend ... but I think it hits the heart of the problem. "High-energy physics" is pretty much "uniquely" physics and so is easy to describe to laymen as "physics". Conversely, the line between something like "solid state physics" and "solid state engineering" can be really blurry (the solid state EE's and solid state physics folks at my alma mater took almost exactly the same classes at the graduate level). So it's a lot harder to describe the differences to laymen even if you point out that solid-state physics is what gave us semiconductors and computer chips.
• justapassenger 6y ago
  > The notion is that if you aren't working on 12 dimensional quantum theories of gravity or the holographic principle and black hole physics, then you aren't a real physicist. Somehow they think that if your work has a real world impact, then it's tainted in some way. I'm not sure how it's gotten this way, but I've actually been told as much by another grad student that my field should be moved to the engineering department because we aren't doing real physics Wow, so The Big Bang Theory is actually pretty good documentary about how modern physic departments operate?
  • hpcjoe 6y ago
    Been out of physics for 23 years, but, yes. Without the studio laugh track, and generally humor. Also add in lots of politics.
• sildur 6y ago
  I think what you do is real physics, as in “real world physics”. Their “real physics” seems to me like a bunch of nerds masturbating to a book of maths.
• BrandoElFollito 6y ago
  The advances in physics are minute compared to fields such as biology. The most minute and useless part is particle physics where the findings are completely unuseable in normal life. Solid state phishing sees some advances, but they are not earth shattering, compared to biology. The day where there will be a substance you put on a cavity of a tooth and it cleans the wound and settles will be something worth of news (that's just an example). At some point, with limited funding, one must make a choice on "fundamental studies" and study what has a chance of having a practical use. Just in case : I have a PhD in particle physics done at CERN and I regret not having taken a field which makes more sense than such impractical studies.
• blablabla123 6y ago
  There's a lot of interesting research (and progress) even going on with Classical Mechanics. E.g. in the 90s it has been shown that even classical Newtonian Physics can yield divergent results which even has a Philosophical impact. Also normal (1-2 particle) Quantum Theory theory is progressing, much more is known about the border between QT and Classical Physics. But of course most resources at Physics departments are dedicated to Solid Matter Physics and High Energy Physics. At least the theoretical flavours of both have a lot of overlap actually and Solid Matter Physics also has applications in the industry. But teaching really focusses on going to one of the 2 topics, at least where I studied. > physics has a communication problem It puzzles me how in 2020 it's still common to believe that the world is a fully deterministic place. That kind of proves that the results stay inside Universities despite a lot of popular science publications.
  • jiggawatts 6y ago
    I've heard about the Newtonian physics thing, but I forgot the specific reference. Could you provide a link to an article?
    • n4r9 6y ago
      They may be referring to Norton's Dome, a thought experiment involving a stationary ball ontop of a cone in which the ball can spontaneously begin moving at any time and still allegedly be obeying Newtonian dynamics: https://en.m.wikipedia.org/wiki/Norton%27s_dome https://en.m.wikipedia.org/wiki/Norton%27s_dome
    • zodiac 6y ago
      Perhaps this? https://en.m.wikipedia.org/wiki/Painlev%C3%A9_conjecture https://en.m.wikipedia.org/wiki/Painlev%C3%A9_conjecture
• hpcjoe 6y ago
  A buddy of mine in grad school (he was an HEP postdoc), once told me (computational condensed matter), that I was working in the dirt left over from the "real" physics. He was a nice guy, but enjoyed ribbing me a bit. That said, I do recollect mostly condescending attitudes from the HEP folks. After finishing my Ph.D., I moved on to a successful career with building, deploying, supporting supercomputers, and the codes that run on them. My friend meanwhile, wound up working in condensed matter physics, modeling semiconductors (which is what I wrote my thesis on) for a large chip company. It seems reality sometimes has a sense of humor.