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This is the classic theorist talking who apparently knows nothing about the real world. It takes a lot of expertise to build a particle accelerator. This expert

by sprash 8y ago

This is the classic theorist talking who apparently knows nothing about the real world. It takes a lot of expertise to build a particle accelerator. This expertise will literally die off, if we stop building accelerators for say the next 50 years. The next generation will have to start at zero again and it will take 80+ years to build the following one instead of 20. In my phd thesis I had to partly rebuild an experiment that was done 35 years ago. (We were not able to improve the systematical errors. The statistics was vastly improved due to modern electronics though). All people who were involved in the old experiment were either retired or dead. The practical problems we encountered were "theoretical trivial" but plenty and time consuming (e.g. finding the right glue with has the right optical density and which does not dissolve the radiation hardened wavelength shifters). If we had just one person to talk to who had done the old experiment we could have done it in 1/4th time or better.

TheOtherHobbes 8y ago
I think people underestimate how incredibly hands-on experimental physics is. It's not just about bolting, gluing, and connecting things you can buy to a few things you have to make. It's cutting-edge applied engineering with some of the closest tolerances you'll find anywhere, supported with post-doc math and often with similarly cutting-edge software development. It gets a lot less attention than theoretical physics, which is a shame because there wouldn't any theoretical physics without it.
- Anon84 8y ago
  I'm all for investing in cutting edge engineering to build something new. I just want the new thing that we're building to actually be useful in itself. A quantum computer, room temperature super conductors, (closer to) human level AI, etc... are all useful things in and of themselves. A particular accelerator a lot less so.
  - sprash 8y ago
    Trust me, "quantum computer, room temperature super conductors, (closer to) human level AI" get plenty of funding to the point where people don't even know where to put money. > I'm all for investing in cutting edge engineering to build something new. If you asked oven engineers 70 years ago to build the most efficient oven they can they probably would have build something that is 2 or 3 percent better than what was currently on the market. But nobody of those oven engineers would have build a microwave. Hence, in order to solve the engineering problems of tomorrow we have to do blue shot fundamental research today because the solution to many problems is not always obvious.
  - Anon84 8y ago
    Yes, you do have to support blue skies research. I just don't think building a bigger hole in Switzerland next to the current is blue skies enough.
arcticfox 8y ago
> This is the classic theorist talking who apparently knows nothing about the real world. This expertise will literally die off, if we stop building accelerators for say the next 50 years. If we're talking about that being the best argument in the real world for building accelerators at the moment, let's spend $200 million on a project to archive every conceivable piece of information related to building an accelerator and save 99% of our budget.
- sprash 8y ago
  In my case the problem was indeed that things that were "obvious" were not documented. Some of those "obvious" things were in fact the result of decades of trail and error. In the end the student did it in that particular way because it has always been done that way and for that reason found not necessary to document it. But even if you document everything many essential things will be gone. Especially knowledge about things that have been tried but don't work because failures are usually not published or documented. It is a little bit like having a document with runes of an ancient language where you may be can find out the meaning of the words and sentences. But you will never find out how the language actually sounded like.
tivert 8y ago
> This is the classic theorist talking who apparently knows nothing about the real world. It takes a lot of expertise to build a particle accelerator. This expertise will literally die off, if we stop building accelerators for say the next 50 years. The next generation will have to start at zero again and it will take 80+ years to build the following one instead of 20. That expertise can be preserved to a large degree. I'm reminded of a story I read about the F-22. Lockheed shut down the production line, but as they did so, they extensively documented every procedure -- to the point of making DVDs of someone performing each production step -- in case they ever needed to restart it again. https://www.reuters.com/article/us-fighter-usa-lockheed-idUSTRE7BC09T20111213 https://www.reuters.com/article/us-fighter-usa-lockheed-idUS... I'd rather attempt something like that than fund even more massive make work programs just to keep the engineering knowledge alive.
- eslaught 8y ago
  I think you're greatly underestimating how difficult it is to preserve this sort of knowledge. A particle accelerator is not a case where you're going to build exactly the same thing again, like you might do with an F-22. Any new accelerator is going to inevitably try to do something new. Therefore, the most important kind of knowledge is the knowledge of the planning and development process, and of all the things that went wrong (or could have gone wrong, but didn't), and how the design was changed to accommodate those. I think this sort of knowledge is incredibly difficult to capture, in large part because people usually don't think about it explicitly; it's almost a reflex as much as anything else. There was a paper a while back about Google's software engineering practices, and one of the interesting points that I didn't see discussed much was that "most software at Google gets rewritten every few years" [1]. The paper includes some justifications, but I think one of the biggest reasons is that it's very hard to institutionalize the sort of knowledge that you get by building something yourself. For the same reasons, I think Lockheed's documentation effort might be sufficient to build an F-22 identical to what they do now, but wouldn't be sufficient to design a new plane inspired by the F-22; and similarly knowing exactly how to build an LHC wouldn't be sufficient to build the next big accelerator. [1]: https://arxiv.org/ftp/arxiv/papers/1702/1702.01715.pdf https://arxiv.org/ftp/arxiv/papers/1702/1702.01715.pdf (see section 2.11)

by sprash 8y ago

TheOtherHobbes 8y ago

I think people underestimate how incredibly hands-on experimental physics is. It's not just about bolting, gluing, and connecting things you can buy to a few things you have to make. It's cutting-edge applied engineering with some of the closest tolerances you'll find anywhere, supported with post-doc math and often with similarly cutting-edge software development. It gets a lot less attention than theoretical physics, which is a shame because there wouldn't any theoretical physics without it.

Anon84 8y ago
I'm all for investing in cutting edge engineering to build something new. I just want the new thing that we're building to actually be useful in itself. A quantum computer, room temperature super conductors, (closer to) human level AI, etc... are all useful things in and of themselves. A particular accelerator a lot less so.
- sprash 8y ago
  Trust me, "quantum computer, room temperature super conductors, (closer to) human level AI" get plenty of funding to the point where people don't even know where to put money. > I'm all for investing in cutting edge engineering to build something new. If you asked oven engineers 70 years ago to build the most efficient oven they can they probably would have build something that is 2 or 3 percent better than what was currently on the market. But nobody of those oven engineers would have build a microwave. Hence, in order to solve the engineering problems of tomorrow we have to do blue shot fundamental research today because the solution to many problems is not always obvious.
- Anon84 8y ago
  Yes, you do have to support blue skies research. I just don't think building a bigger hole in Switzerland next to the current is blue skies enough.

arcticfox 8y ago

> This is the classic theorist talking who apparently knows nothing about the real world. This expertise will literally die off, if we stop building accelerators for say the next 50 years. If we're talking about that being the best argument in the real world for building accelerators at the moment, let's spend $200 million on a project to archive every conceivable piece of information related to building an accelerator and save 99% of our budget.

sprash 8y ago
In my case the problem was indeed that things that were "obvious" were not documented. Some of those "obvious" things were in fact the result of decades of trail and error. In the end the student did it in that particular way because it has always been done that way and for that reason found not necessary to document it. But even if you document everything many essential things will be gone. Especially knowledge about things that have been tried but don't work because failures are usually not published or documented. It is a little bit like having a document with runes of an ancient language where you may be can find out the meaning of the words and sentences. But you will never find out how the language actually sounded like.

tivert 8y ago

> This is the classic theorist talking who apparently knows nothing about the real world. It takes a lot of expertise to build a particle accelerator. This expertise will literally die off, if we stop building accelerators for say the next 50 years. The next generation will have to start at zero again and it will take 80+ years to build the following one instead of 20. That expertise can be preserved to a large degree. I'm reminded of a story I read about the F-22. Lockheed shut down the production line, but as they did so, they extensively documented every procedure -- to the point of making DVDs of someone performing each production step -- in case they ever needed to restart it again. https://www.reuters.com/article/us-fighter-usa-lockheed-idUSTRE7BC09T20111213 https://www.reuters.com/article/us-fighter-usa-lockheed-idUS... I'd rather attempt something like that than fund even more massive make work programs just to keep the engineering knowledge alive.

eslaught 8y ago
I think you're greatly underestimating how difficult it is to preserve this sort of knowledge. A particle accelerator is not a case where you're going to build exactly the same thing again, like you might do with an F-22. Any new accelerator is going to inevitably try to do something new. Therefore, the most important kind of knowledge is the knowledge of the planning and development process, and of all the things that went wrong (or could have gone wrong, but didn't), and how the design was changed to accommodate those. I think this sort of knowledge is incredibly difficult to capture, in large part because people usually don't think about it explicitly; it's almost a reflex as much as anything else. There was a paper a while back about Google's software engineering practices, and one of the interesting points that I didn't see discussed much was that "most software at Google gets rewritten every few years" [1]. The paper includes some justifications, but I think one of the biggest reasons is that it's very hard to institutionalize the sort of knowledge that you get by building something yourself. For the same reasons, I think Lockheed's documentation effort might be sufficient to build an F-22 identical to what they do now, but wouldn't be sufficient to design a new plane inspired by the F-22; and similarly knowing exactly how to build an LHC wouldn't be sufficient to build the next big accelerator. [1]: https://arxiv.org/ftp/arxiv/papers/1702/1702.01715.pdf https://arxiv.org/ftp/arxiv/papers/1702/1702.01715.pdf (see section 2.11)