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Comment by jiggawatts | Hacker News Reader

Compare a bunch of chemical formulas and equations in this blog with Richard Feynman's explanation of fire: https://www.youtube.com/watch?v=N1pIYI5JQLE

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Wow. I read the initial blog post (well I read the start, and skimmed the rest) and I thought it was interesting but I am just not motivated to dive into something so complex. I learned nothing.

Then I watched Richard Feynman's explanation and feel like I learned something! And was motivated about it!

Feynman's explanation is obviously great, but it and the blog have different goals. There is really no sense in which fire is best explained by Planck's Law. Obviously the goal of the blog post is to explore how physics is nested, with complex phenomena the result of simpler laws which are the result of even simpler laws. I mean, the part that's about chemistry specifically, which most would call the part that's about fire, is only the first 1/5 or so. It is easier to learn and feel motivated to learn less physics rather than more, and Feynman's gift was imparting the most essential information with the least physics possible, a sort of distillation of physicist-intuition for the layman.

>>I watched Richard Feynman's explanation and feel like I learned something!

I don't know the link to the video on YouTube, but there was one interview where they were discussing why Math appears hard to so many people. Basically people look at solving Math problem like an elaborate heuristic needed to be memorised to solve the problem.

He proceeds to explain that's for people who don't understand what they are doing.

To understand anything at all, is to start with basic assumptions/axioms and logical rules of manipulating them and moving forward from there.

Here is feynman on AI: https://www.youtube.com/watch?v=ipRvjS7q1DI

Feynman turned his focus to computing ( AI, heuristics, quantum computing ) later on his life.

Thanks for that link, it was tremendously insightful.

His lectures on computation is a good book.

I hear the gravitation one is also good but it relies on a good knowledge of quantum field theory which I do not really possess so cannot judge.

What if... the author wasn't aiming this post for a completely lay audience, but rather someone with a undergraduate/graduate level of mathematics/physics background who was interested in learning more about some phenomenon?

Nope everything needs to be completely intuitive, explaining in detail is completely wrong /s

I think both can complement each other, but it is definitely nice to go into the details. Watch the Feynman explanation then try to use that as you go through the actual details. The initial more hand wavy, but morally correct explanation, gives you something to latch onto, and then you can use that to guide your reasoning in the more complicated steps.

Honestly the idea or expectation that things need to be read linearly is also wrong, you should include some reasonable level of detail and elaboration in your writing, but organise it so it can be picked over. You can switch betweeen levels too.

Or Michael Faraday's masterpiece "the chemical history of a candle", which deep-dives not only into what every part of the fire is, but also how we know what it is.

https://www.gutenberg.org/cache/epub/14474/pg14474.txt

The whole book is a delight to read, but I really like this part:

> And now I want you to follow me in this explanation. You would hardly think that all those substances which fly about London, in the form of soots and blacks, are the very beauty and life of the flame, and which are burned in it as those iron filings were burned here...

> I want you now to follow me in this point,--that whenever a substance burns, as the iron filings burnt in the flame of gunpowder, without assuming the vaporous state (whether it becomes liquid or remains solid), it becomes exceedingly luminous. I have here taken three or four examples apart from the candle, on purpose to illustrate this point to you; because what I have to say is applicable to all substances, whether they burn or whether they do not burn,--that they are exceedingly bright if they retain their solid state, and that it is to this presence of solid particles in the candle-flame that it owes its brilliancy.

>... This flame has carbon in it; but I will take one that has no carbon in it. There is a material, a kind of fuel--a vapour, or gas, whichever you like to call it--in that vessel, and it has no solid particles in it; so I take that because it is an example of flame itself burning without any solid matter whatever; and if I now put this solid substance in it, you see what an intense heat it has, and how brightly it causes the solid body to glow. This is the pipe through which we convey this particular gas, which we call hydrogen, and which you shall know all about next time we meet. And here is a substance called oxygen, by means of which this hydrogen can burn; and although we produce, by their mixture, far greater heat[8] than you can obtain from the candle, yet there is very little light. If, however, I take a solid substance, and put that into it, we produce an intense light If I take a piece of lime, a substance which will not burn, and which will not vaporise by the heat (and because it does not vaporise, remains solid, and remains heated), you will soon observe what happens as to its glowing. I have here a most intense heat, produced by the burning of hydrogen in contact with the oxygen; but there is as yet very little light--not for want of heat, but for want of particles which can retain their solid state; but when I hold this piece of lime in the flame of the hydrogen as it burns in the oxygen, see how it glows! This is the glorious lime-light, which rivals the voltaic-light, and which is almost equal to sunlight. I have here a piece of carbon or charcoal, which will burn and give us light exactly in the same manner as if it were burnt as part of a candle. The heat that is in the flame of a candle decomposes the vapour of the wax, and sets free the carbon particles--they rise up heated and glowing as this now glows, and then enter into the air. But the particles when burnt never pass off from a candle in the form of carbon. They go off into the air as a perfectly invisible substance, about which we shall know hereafter.

> Is it not beautiful to think that such a process is going on, and that such a dirty thing as charcoal can become so incandescent? You see it comes to this--that all bright flames contain these solid particles; all things that burn and produce solid particles, either during the time they are burning, as in the candle, or immediately after being burnt, as in the case of the gunpowder and iron-filings,--all these things give us this glorious and beautiful light.

>... That, however, is not the only thing I wish to mention. If I take a flame sufficiently large, it does not keep that homogeneous, that uniform condition of shape, but it breaks out with a power of life which is quite wonderful. I am about to use another kind of fuel, but one which is truly and fairly a representative of the wax or tallow of a candle. I have here a large ball of cotton, which will serve as a wick. And, now that I have immersed it in spirit and applied a light to it, in what way does it differ from an ordinary candle? Why, it differs very much in one respect, that we have a vivacity and power about it, a beauty and a life entirely different from the light presented by a candle. You see those fine tongues of flame rising up. You have the same general disposition of the mass of the flame from below upwards; but, in addition to that, you have this remarkable breaking out into tongues which you do not perceive in the case of a candle. Now, why is this? I must explain it to you...

I also really enjoyed Bill Hammack's series of videos based on Faraday's lectures: http://www.engineerguy.com/faraday

> This is the glorious lime-light

Well holy heck. TIL.

James Burke's Connections episode 9: Countdown [1], covers the invention of limelight, gives a history of the technology and places it in context. The entire series is intertwined (thus the title, Connections), but if you start watching Ep. 9 at 18:30 it gives plenty of preamble for the need for the invention before introducing it and covering its adoption.

[1] https://archive.org/details/james-burke-connections_s01e09