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>Tesla and SpaceX are great but I'm not aware of fundamental engineering principles they have overthrown. No, but it is a pretty good claim to show an understa

>Tesla and SpaceX are great but I'm not aware of fundamental engineering principles they have overthrown. No, but it is a pretty good claim to show an understanding of the basics that they supposedly haven't learned.

potatolicious 13y ago
How so? The point being made in the blog post is that Musk has a severe misunderstanding of the fundamentals of civil engineering. That Musk runs a company that has successfully engineered cars and spacecraft in no way makes him qualified to construct the Hyperloop. Civil engineering isn't mechanical engineering isn't chemical engineering isn't aerospace engineering. These are different disciplines. Being a talented industrialist in one (or more) of these do not imply capability in any of the others.
- lutusp 13y ago
  > Civil engineering isn't mechanical engineering isn't chemical engineering isn't aerospace engineering. That's true, but all of them derive from the same set of first principles, those defined by physics. > Being a talented industrialist in one (or more) of these do not imply capability in any of the others. Not true -- expertise is not implied, but capability certainly is. In this specific case, to predict the behavior of an evacuated transport tube, and given that the project doesn't resemble any existing projects, one could hardly do better than have a background in spacecraft booster design.
  - zorpner 13y ago
    > That's true, but all of them derive from the same set of first principles, those defined by physics. More is different (PDF link: http://robotics.cs.tamu.edu/dshell/cs689/papers/anderson72more_is_different.pdf http://robotics.cs.tamu.edu/dshell/cs689/papers/anderson72mo... ). Much like a knowledge of physics is insufficient to draw conclusions about biochemistry, knowledge of basic physical laws tells you very little about the fundamentals of a practical engineering field. The theory and laws of e.g. civil engineering are typically traceable back to abstract physical principles, but are not strictly derivable from them.
    - lutusp 13y ago
      > More is different (PDF link: http://robotics.cs.tamu.edu/dshell/cs689/papers/anderson72mo.. http://robotics.cs.tamu.edu/dshell/cs689/papers/anderson72mo.... ). What? A link to a paywalled article with no abstract? That was constructive. Here's a real link: https://www.tkm.kit.edu/downloads/TKM1_2011_more_is_different_PWA.pdf https://www.tkm.kit.edu/downloads/TKM1_2011_more_is_differen... As to the article's content, it's philosophy without supporting evidence (meaning it's philosophy), and its conclusions are regularly refuted by the many examples that connect physical fundamentals with everyday reality. Example? Quantum theory and computers -- as separate as the two may seem, we can't have the second without a detailed knowledge of the first. > Much like a knowledge of physics is insufficient to draw conclusions about biochemistry ... In the final analysis, all of biochemistry derives from biology and chemistry, each of which derives from physics. Relevant in that regard is the fact that chemistry turns out to be applied quantum physics, to a shocking number of decimal places. > The theory and laws of e.g. civil engineering are typically traceable back to abstract physical principles, but are not strictly derivable from them. Not true. Either civil engineering is "strictly derivable" from physics, or it's not part of reality. The behavior of concrete over time, as just one example -- we know what will become of it in the long term, and modern quantum theory tells us why. Philosophical articles like "More Is Different" represent nothing more or less than physics envy. They're interesting and deserve to be heard, but in the reality footrace, events annoy the authors by reliably overtaking their philosophical positions.
      - eli_gottlieb 13y ago
        There is a difference between reality and academic physics. It is trivial to say engineering knowledge is derived from reality, and it's wrong to say it's derived/derivable from purely theoretical/academic knowledge of physics -- especially because good engineering requires knowledge of man-made safety standards and such. Engineering is a corpus of knowledge that has been slowly and with great difficulty hewed from the raw rock of real experience over hundreds of years. It is not just a branch of math derivable from axioms. Show some respect.
        13y ago
  - potatolicious 13y ago
    I can't disagree more. I'm a mechanical engineering by schooling (what am I doing writing code?!) and it still routinely shocks me the sort of intriguing misconceptions I hear coming out of the mouths of very smart, very technical people. The fact that mechanical engineering and civil engineering and aerospace engineering all derive from basic physical laws is rather meaningless - engineering isn't about first principles, it's about the extremely complex task of putting these to use. To make an analogy to software, that's like saying "writing code for a Martian probe isn't very different from writing code for a website, it's all the same first principles". In this case, the author's thesis is that Musk is applying analysis methods that are wholly inapplicable to civil engineering, and fails to account to the scale of the structure, and makes faulty assumptions about the validity of simulating the structure in small segments. This is the sort of thing you see when you cross someone who is an expert in one field into another where they have no expertise - but they know just enough to get started. I write mobile apps for a living. I can probably hold a decent conversation with a kernel hacker, but I am in no way qualified to design the next uber-kernel of the future. Traditional engineering is no different.
    - lutusp 13y ago
      > I'm a mechanical engineering by schooling (what am I doing writing code?!) and it still routinely shocks me the sort of intriguing misconceptions I hear coming out of the mouths of very smart, very technical people. That's true, and I've had similar experiences, but it doesn't argue against my saying that these engineering disciplines have many basics in common. My only reason for posting was to argue against the idea that different engineering fields have no common base. They either do, or they're not based in science, which is the common base for all engineering fields. As to a new project that has little in common with existing projects or established engineering fields, the obvious solution is to depend on basic science rather than nonexistent engineering projects, which would be the best approach to a project like this one. All new engineering projects teach us one thing -- no matter how many advance expectations and predictions, by the time the project is operational, all of us will be educated in new principles that no one anticipated.
      - threeseed 13y ago
  - mikeash 13y ago
    How, then, do you account for the very basic and substantial errors described in the article?
    - lutusp 13y ago
      > How, then, do you account for the very basic and substantial errors described in the article? Surely you don't think a single counterexample -- or a dozen counterexamples -- refute well-established principles? The argument was that various engineering disciples are independent of each other and of physics. That's very clearly false and smacks of post-modernism (i.e. that everything is a matter of opinion, not evidence), and it's hardly supported by an example -- or a dozen examples -- where someone gets the engineering wrong.
      - mikeash 13y ago
        I was addressing your claim about this specific case: "In this specific case, to predict the behavior of an evacuated transport tube, and given that the project doesn't resemble any existing projects, one could hardly do better than have a background in spacecraft booster design." Seems to me that one could do a lot better than having a background in spacecraft booster design, as the fairly trivial errors pointed out in this article illustrate.
      - dragonwriter 13y ago
        > The argument was that various engineering disciples are independent of each other and of physics. No, actually, they were argued to be different than each other, but no one in this thread argued that they were independent of each other or that any of them was independent of physics. Inasmuch as that's the position you are arguing against, it is a strawman.
        lutusp 13y ago
        >> The argument was that various engineering disciples are independent of each other and of physics. > No, actually, they were argued to be different than each other, but no one in this thread argued that they were independent of each other or that any of them was independent of physics. False. Read this quote: "The fact that mechanical engineering and civil engineering and aerospace engineering all derive from basic physical laws is rather meaningless - engineering isn't about first principles ..." To say, as this correspondent did, that "engineering isn't about first principles", is to argue that it has nothing to do with science, because science establishes first principles. > Inasmuch as that's the position you are arguing against, it is a strawman. Well, since you can't be bothered to read the thread and find out what positions people have taken and that I'm arguing against, there's no point to this.
  - moogleii 13y ago
    No offense, but I think you are seriously underestimating several domains of knowledge.
    - lutusp 13y ago
      > No offense, but I think you are seriously underestimating several domains of knowledge. How so? By insisting on their connection with established scientific principles? Astrologers would love for me to do that, as would psychologists.
- stonemetal 13y ago
  His primary argument is about thermal expansion. Are you claiming aerospace and automotive engineers make no study of thermal expansion? I could see your point if the proposal was about a dirt retaining wall or aqueduct where the other two disciplines wouldn't be well versed in the material's properties, but I am not seeing something CE specific in the thermal expansion of steel. Yes, “stringer” is also a common word in structural engineering, especially in bridge design, but something that reinforces a tube wall is a stiffener, not a stringer. Update: I am reminded by Matthew Hunt on Twitter that “stringer” is commonly used in aircraft design. I should have remembered that. Given this quote how do we know they aren't in violent agreement but talking past each other because they are using terms from different disciplines?

potatolicious 13y ago

How so? The point being made in the blog post is that Musk has a severe misunderstanding of the fundamentals of civil engineering. That Musk runs a company that has successfully engineered cars and spacecraft in no way makes him qualified to construct the Hyperloop. Civil engineering isn't mechanical engineering isn't chemical engineering isn't aerospace engineering. These are different disciplines. Being a talented industrialist in one (or more) of these do not imply capability in any of the others.

lutusp 13y ago
> Civil engineering isn't mechanical engineering isn't chemical engineering isn't aerospace engineering. That's true, but all of them derive from the same set of first principles, those defined by physics. > Being a talented industrialist in one (or more) of these do not imply capability in any of the others. Not true -- expertise is not implied, but capability certainly is. In this specific case, to predict the behavior of an evacuated transport tube, and given that the project doesn't resemble any existing projects, one could hardly do better than have a background in spacecraft booster design.
- zorpner 13y ago
  > That's true, but all of them derive from the same set of first principles, those defined by physics. More is different (PDF link: http://robotics.cs.tamu.edu/dshell/cs689/papers/anderson72more_is_different.pdf http://robotics.cs.tamu.edu/dshell/cs689/papers/anderson72mo... ). Much like a knowledge of physics is insufficient to draw conclusions about biochemistry, knowledge of basic physical laws tells you very little about the fundamentals of a practical engineering field. The theory and laws of e.g. civil engineering are typically traceable back to abstract physical principles, but are not strictly derivable from them.
  - lutusp 13y ago
    > More is different (PDF link: http://robotics.cs.tamu.edu/dshell/cs689/papers/anderson72mo.. http://robotics.cs.tamu.edu/dshell/cs689/papers/anderson72mo.... ). What? A link to a paywalled article with no abstract? That was constructive. Here's a real link: https://www.tkm.kit.edu/downloads/TKM1_2011_more_is_different_PWA.pdf https://www.tkm.kit.edu/downloads/TKM1_2011_more_is_differen... As to the article's content, it's philosophy without supporting evidence (meaning it's philosophy), and its conclusions are regularly refuted by the many examples that connect physical fundamentals with everyday reality. Example? Quantum theory and computers -- as separate as the two may seem, we can't have the second without a detailed knowledge of the first. > Much like a knowledge of physics is insufficient to draw conclusions about biochemistry ... In the final analysis, all of biochemistry derives from biology and chemistry, each of which derives from physics. Relevant in that regard is the fact that chemistry turns out to be applied quantum physics, to a shocking number of decimal places. > The theory and laws of e.g. civil engineering are typically traceable back to abstract physical principles, but are not strictly derivable from them. Not true. Either civil engineering is "strictly derivable" from physics, or it's not part of reality. The behavior of concrete over time, as just one example -- we know what will become of it in the long term, and modern quantum theory tells us why. Philosophical articles like "More Is Different" represent nothing more or less than physics envy. They're interesting and deserve to be heard, but in the reality footrace, events annoy the authors by reliably overtaking their philosophical positions.
    - eli_gottlieb 13y ago
      There is a difference between reality and academic physics. It is trivial to say engineering knowledge is derived from reality, and it's wrong to say it's derived/derivable from purely theoretical/academic knowledge of physics -- especially because good engineering requires knowledge of man-made safety standards and such. Engineering is a corpus of knowledge that has been slowly and with great difficulty hewed from the raw rock of real experience over hundreds of years. It is not just a branch of math derivable from axioms. Show some respect.
      - 13y ago
- potatolicious 13y ago
  I can't disagree more. I'm a mechanical engineering by schooling (what am I doing writing code?!) and it still routinely shocks me the sort of intriguing misconceptions I hear coming out of the mouths of very smart, very technical people. The fact that mechanical engineering and civil engineering and aerospace engineering all derive from basic physical laws is rather meaningless - engineering isn't about first principles, it's about the extremely complex task of putting these to use. To make an analogy to software, that's like saying "writing code for a Martian probe isn't very different from writing code for a website, it's all the same first principles". In this case, the author's thesis is that Musk is applying analysis methods that are wholly inapplicable to civil engineering, and fails to account to the scale of the structure, and makes faulty assumptions about the validity of simulating the structure in small segments. This is the sort of thing you see when you cross someone who is an expert in one field into another where they have no expertise - but they know just enough to get started. I write mobile apps for a living. I can probably hold a decent conversation with a kernel hacker, but I am in no way qualified to design the next uber-kernel of the future. Traditional engineering is no different.
  - lutusp 13y ago
    > I'm a mechanical engineering by schooling (what am I doing writing code?!) and it still routinely shocks me the sort of intriguing misconceptions I hear coming out of the mouths of very smart, very technical people. That's true, and I've had similar experiences, but it doesn't argue against my saying that these engineering disciplines have many basics in common. My only reason for posting was to argue against the idea that different engineering fields have no common base. They either do, or they're not based in science, which is the common base for all engineering fields. As to a new project that has little in common with existing projects or established engineering fields, the obvious solution is to depend on basic science rather than nonexistent engineering projects, which would be the best approach to a project like this one. All new engineering projects teach us one thing -- no matter how many advance expectations and predictions, by the time the project is operational, all of us will be educated in new principles that no one anticipated.
    - threeseed 13y ago
- mikeash 13y ago
  How, then, do you account for the very basic and substantial errors described in the article?
  - lutusp 13y ago
    > How, then, do you account for the very basic and substantial errors described in the article? Surely you don't think a single counterexample -- or a dozen counterexamples -- refute well-established principles? The argument was that various engineering disciples are independent of each other and of physics. That's very clearly false and smacks of post-modernism (i.e. that everything is a matter of opinion, not evidence), and it's hardly supported by an example -- or a dozen examples -- where someone gets the engineering wrong.
    - mikeash 13y ago
      I was addressing your claim about this specific case: "In this specific case, to predict the behavior of an evacuated transport tube, and given that the project doesn't resemble any existing projects, one could hardly do better than have a background in spacecraft booster design." Seems to me that one could do a lot better than having a background in spacecraft booster design, as the fairly trivial errors pointed out in this article illustrate.
    - dragonwriter 13y ago
      > The argument was that various engineering disciples are independent of each other and of physics. No, actually, they were argued to be different than each other, but no one in this thread argued that they were independent of each other or that any of them was independent of physics. Inasmuch as that's the position you are arguing against, it is a strawman.
      - lutusp 13y ago
        >> The argument was that various engineering disciples are independent of each other and of physics. > No, actually, they were argued to be different than each other, but no one in this thread argued that they were independent of each other or that any of them was independent of physics. False. Read this quote: "The fact that mechanical engineering and civil engineering and aerospace engineering all derive from basic physical laws is rather meaningless - engineering isn't about first principles ..." To say, as this correspondent did, that "engineering isn't about first principles", is to argue that it has nothing to do with science, because science establishes first principles. > Inasmuch as that's the position you are arguing against, it is a strawman. Well, since you can't be bothered to read the thread and find out what positions people have taken and that I'm arguing against, there's no point to this.
- moogleii 13y ago
  No offense, but I think you are seriously underestimating several domains of knowledge.
  - lutusp 13y ago
    > No offense, but I think you are seriously underestimating several domains of knowledge. How so? By insisting on their connection with established scientific principles? Astrologers would love for me to do that, as would psychologists.
stonemetal 13y ago
His primary argument is about thermal expansion. Are you claiming aerospace and automotive engineers make no study of thermal expansion? I could see your point if the proposal was about a dirt retaining wall or aqueduct where the other two disciplines wouldn't be well versed in the material's properties, but I am not seeing something CE specific in the thermal expansion of steel. Yes, “stringer” is also a common word in structural engineering, especially in bridge design, but something that reinforces a tube wall is a stiffener, not a stringer. Update: I am reminded by Matthew Hunt on Twitter that “stringer” is commonly used in aircraft design. I should have remembered that. Given this quote how do we know they aren't in violent agreement but talking past each other because they are using terms from different disciplines?