Comment by credit_guy | Hacker News Reader

Comment by credit_guy | Hacker News Reader

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I'm not sure why this was posted. Presumable u/jameshart thinks it is relevant to some current events.

If these events have anything to do with nuclear fission, then I don't find Admiral Rickover's remarks relevant at all. Those remarks were right on the money back in 1953, but we are in 2023 now. Nobody is suggesting we can build reactors easily, or with "off-the-shelf" components, or that they'd be cheap, or can be built quickly, etc. We know reactors are complex, expensive, take a long time to build.

But reactors are not theoretical anymore. We've built hundreds of them. Of many types. Pressurized water reactors the most; they've turned out to be quite good from a number of points of view. But we've built boiling water reactors, Candu reactors, even sodium cooled reactors, reactors cooled with CO2, etc.

When people talk about building new reactors, it's not paper reactors we're talking about. It's reactors where the world has thousands of reactor-years experience. They are complex, they have to go through an arduous regulatory approval process, but they are definitely not vaporware.

So, how is Rickover's lament relevant today?

"An academic reactor or reactor plant almost always has the following basic characteristics:

It is simple. It is small. It is cheap. It is light. It can be built very quickly. It is very flexible in purpose (“omnibus reactor”) Very little development is required. It will use mostly “off-the-shelf” components. The reactor is in the study phase. It is not being built now. On the other hand, a practical reactor plant can be distinguished by the following characteristics:

It is being built now. It is behind schedule. It is requiring an immense amount of development on apparently trivial items. Corrosion, in particular, is a problem. It is very expensive. It takes a long time to build because of the engineering development problems. It is large. It is heavy. It is complicated. "

The above still seems to be relevant, it spells out the differences between paper exercises and the finished product. On paper the many thousands of subtleties of real things are rarely taken into account

i.e. frictionless, motionless, perfectly rigid, etc., spherical cows are the norm.

Precisely this. In theory, there will never be unexpected latency to the database, so you don't need to worry about overwhelming it and can just immediately retry. In theory, your instance's CPU won't throttle due to a shared tenant on the host running an AVX-512 instruction, so the profiling you did in staging is valid and can be trusted.

Nothing to do with current events. Nothing to do with (specifically) anything happening in nuclear engineering.

Just thought it captured a timeless truth of engineering - that there are two kinds of project: beautiful clever designs that will solve all your problems (but that haven’t yet been built); and messy, expensive, late designs that are actually working.

Related to the nirvana fallacy discussed here the other day, where user acidburnNSA mentioned it - I felt it deserved a discussion of its own: https://news.ycombinator.com/item?id=36078781

I think it’s been posted on HN because it’s relevant to the way software development can be performed in ignorance of production environments - or can be done in a production-aware (more SRE focused) way.

It is much more widely applicable than just to nuclear reactor design. There is a steady drumbeat of articles here (and elsewhere) of developments which (on paper) are allegedly game-changing. This is prevalent in medicine of course, but also (off the top of my head) space travel, batteries, solar cells, everything AI, programming languages and frameworks, self-driving cars, flying cars, even the perennial favorite but now-obsolescent internal-combustion car engine, and, yes, new nuclear reactor designs.

Companies are still trying to build "affordable" nuclear reactors. E.g.: https://www.rolls-royce.com/innovation/small-modular-reactor...

Rolls-Royce is the last company one can accuse of promising a "paper reactor": they build UK's naval nuclear reactors, exactly Rickover's specialty.

It has nothing to do with nuclear reactors. It's about all the systems we create. The difference between paper and real ones.

You could apply this to almost any engineering endeavor.

I took it as a metaphor for other types of engineering. With software engineering we teach people how to walk a tree, schedule threads, do matrix transformations, etc. in school, then throw them into a job where the big problems are more like "How do we make the web page fast enough for the vendors in Mumbai without violating GDPR?"

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