HN Theater @HNTheaterMonth

The carbon in plants comes from the air, not the soil.

Source: Richard Feynman: https://www.youtube.com/watch?v=N1pIYI5JQLE

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

⬐ qiskit

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.

⬐ jdkee

Thanks for that link, it was tremendously insightful.

⬐ mhh__

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.

⬐ philipfweiss

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?

⬐ fennecs

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.

⬐ jbay808

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...

⬐ ThePowerOfFuet

> This is the glorious lime-light

Well holy heck. TIL.

⬐ h2odragon

See also bone fires (bonfires)

⬐ Maursault

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

⬐ greenyoda

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

⬐ mortenjorck

Sometimes tangential HN comments are a gift. Thank you for this one.

⬐ throwaway0a5e

That's a great explanation of fire by itself does you no favors if you are trying to differentiate fire from normal oxidation.

⬐ Graffur

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!

⬐ kamaal

>>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.

⬐ ravi-delia

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.

> Wax is made of hydrogen and carbon.

Too bad he doesn't explain where the energy in the wax came from like Feynman does when explaining fire:

https://youtu.be/N1pIYI5JQLE

Paraffin wax is derived from petroleum, so like the wood in Feynman's explanation, the energy is from the sun via ancient photosynthesis.

⬐ throwawaysea

All fossil fuels are solar power in that sense?

⬐ hyperman1

Most of them. There are also the nuclear reactions in the earth's core.

⬐ kgwgk

I know that there are organisms that thrive in geotermally heated environments, but do they really produce fossil fuels?

⬐ 542458

Only in the most pendantic of senses - a bit like arguing that my car is fusion powered because it runs on gas that was originally given energy from the sun. I suppose in a sense everything in the universe is powered by whatever triggered the Big Bang.

⬐ purple_ferret

Or more recent photosynthesis. You can make candle wax out of soy, beeswax, crisco, etc.

⬐ kgwgk

Also from animal fat.

I first learned the idea of fire as breaking molecular bonds formed during photosynthesis from a video snippet of Richard Feynman [1].

1. https://www.youtube.com/watch?v=N1pIYI5JQLE

Related, one of my favourite videos: Richard Feynmann explains fire:

https://www.youtube.com/watch?v=N1pIYI5JQLE

https://youtu.be/N1pIYI5JQLE

Feynman explains fire. I’m a big fan and believe his crude straight to the point style, coupled with an incredible ability to storytell is what made him special. I think it’s pure, genuine, curiosity and the intellectual capacity to understand the complexities.

⬐ eliotpeper

This is extremely good.

⬐ jcims

What a gift. I love how he just squirms with enthusiasm.

We have a couple large fields by our home that alternate yearly between soybeans and corn. The amount of biomass that accumulated in a corn field between mid June and mid July is remarkable. Knowing that nearly all of that mass is from the atmosphere and not the ground is quite a prospective shifter.

Related Explanation/Discovery : "But if you ask, where the substance comes from... the trees come out of the air?!" -Richard Feynman https://www.youtube.com/watch?v=N1pIYI5JQLE&feature=youtu.be...

Feynmann had some really nice description of this:

https://www.youtube.com/watch?v=N1pIYI5JQLE

I thought this would be a link to a Richard Feynman video where he 'explains' fire. But it isn't, so here you go: https://www.youtube.com/watch?v=N1pIYI5JQLE

⬐ JoachimS

Dang you beat me to it.

> but solar panels don't grow out of dirt

Neither do leaves, they grow out of the air ;)

https://www.youtube.com/watch?v=N1pIYI5JQLE

⬐ sidcypher

Good, the video shows Feynman talking about fire and not Feynman burning. I was a bit worried there.

⬐ toothbrush

I'm going to go ahead and paste the top comment from YouTube here:

“They say simplicity is genius. School teachers should watch and learn from this man. Imagine the kid's imaginations being stoked by this approach.”

Indeed.

Checkout this explanation of fire by Richard Feynman - its a really eye opening perspective

https://www.youtube.com/watch?v=N1pIYI5JQLE

He explains the light of a fire is just the light of the Sun, it's just been stored in the wood

Let Feynman explain it to them - https://www.youtube.com/watch?v=N1pIYI5JQLE

Obligatory link to Feynman's explanation:

http://youtu.be/N1pIYI5JQLE

tldr - By going vegetarian at first, the Mars colony accumulates usable biomass faster.

(Also, the "Up on the Farm" chapter of this book is a good background read for this discussion: http://www.nss.org/settlement/ColoniesInSpace/colonies_chap0... )

The thing to remember here, is that, as Feynmann says, plants make themselves out of air! < http://www.youtube.com/watch?v=N1pIYI5JQLE > Go back to your basic biology education and remember the formula for photosynthesis. < http://en.wikipedia.org/wiki/Photosynthesis >

So a Mars colony's farms are basically chemical solar collectors doing two things: 1) providing chemical energy to the colonists (food) and 2) Converting Martian CO2 and water into biomass. If you introduce too many warm blooded animals into the system, a lot of your energy input gets wasted as livestock body heat. So by going vegetarian at first, the Mars colony accumulates usable biomass faster. The faster you accumulate biomass, the faster you can make more biomass.

This is also the principle behind the tactic of mostly making construction vehicles at first in Starcraft, or concentrating early on customer acquisition in a startup.

> I suspect it's not about transportation costs so much as ecology. The amount of biomass available to animals at the top of the food pyramid is inversely proportional to the height of the pyramid.

Right on. The thing to remember here, is that, as Feynmann says, plants make themselves out of air! < http://www.youtube.com/watch?v=N1pIYI5JQLE > (If you doubt, go back to your basic biology education and remember the formula for photosynthesis.)

So a Mars colony's farms are basically chemical solar collectors doing two things: 1) providing chemical energy to the colonists (food) and 2) Converting Martian CO2 and water into biomass. If you introduce too many warm blooded animals into the system, a lot of your energy input gets wasted as livestock body heat.

tldr - By going vegetarian at first, the Mars colony accumulates usable biomass faster.

If anyone wants to know the answer to that question, Richard Feynman explains it wonderfully: (He starts talking about trees at 2:00, but his explanation of fire is equally elegant!) http://www.youtube.com/watch?v=N1pIYI5JQLE

My first instinct was to say that a tree's mass comes from dead stars. Imagining how it got from those stars to the air that eventually becomes the tree would keep you busy for a while :D

I'd really like to hear Richard Feynman's answer. I'm sure if an 11 year old had asked the question, instead of a journalist, it would be the perfect answer. (I'm referring to an interview series with him: http://www.youtube.com/watch?v=N1pIYI5JQLE)

Makes me sad to think I will never meet this man, nor ever be as awesome.

Richard Feynman explains why fire happens in layman's terms of Quantum Electrodynamics.

I don't want to offend anyone but that article was extremely boring (I did end up reading it). I suppose I'd seen the Richard Feynman video on fire and trees quite recently beforehand and was in an intolerant mood. But it's impossible to stay in any kind of negative mood if you watch Feynman, his love of knowledge is just infectious.

http://www.youtube.com/watch?v=N1pIYI5JQLE

Feynman knows:

http://www.youtube.com/watch?v=N1pIYI5JQLE

⬐ heycarsten

Turns out he has a rant about this very issue: http://www.youtube.com/watch?v=MO0r930Sn_8

⬐ BrandonM

Well there went a couple hours...

⬐ dtf

Found this great comment in underneath that particular YouTube video:

"He was just a curious kid in a grown up's body."

You've only got to watch Feynman's face as he's telling the story, or any story for that matter. His excitement and enthusiasm for the curiosities of life is infectious.

⬐ None

None

⬐ ckuehne

Can't upvote you enough for this. By the way, Feynman also knows the difference "between knowing the name of something and knowing something": http://www.youtube.com/watch?v=05WS0WN7zMQ

⬐ ostso

More Feynman on the same topic ("Energy makes it go"): http://physics.gu.se/~f3aamp/teaching/wakalix.html

⬐ joubert

The difference between knowing the name for something and knowing something, is probably most clearly elucidated when you ask someone who believes in a deity, what it is. The answer is invariably contains contradictory, unreconcilable aspects.

⬐ scrod

While we're talking about Feynman, I think most people here could relate to his perspective on uninterrupted time, and the avoidance of administrative work: http://www.youtube.com/watch?v=Y08g3OXAA14&NR=1

⬐ jules

This. He really articulates clearly the difference between two ways of thinking. Thinking by really understanding then translating the thoughts into words and thinking by manipulating words.

⬐ johnohara

One of my favorites:

Dick acted as a consultant for a company in Switzerland, which took him there every summer. About 1982 or so, I had business in Europe, and I met Dick in Geneva. We decided to kick around for several days. We did the shops and the countryside on the first day, and on the second day, he asked what I'd like to do. I said, "Well, if it isn't too much like a postman's holiday, I'd like to go over to CERN," which is the European particle accellerator, where so much particle physics is done, and where Dick used to work a number of years before. He said, "Sure." So we went over there, and Dick couldn't find his way around because the buildings had changed. We finally found our way in, and looked into a room where there were some physicists doing work on the blackboard. One of them spotted Feynman, and pretty soon there was a crowd gathered, and the director came in. He decided they'd take us on a tour. We went into a 007, James Bond cave underneath the ground, with all this wonderful high-technology equipment. There was a giant machine that was going to be rolled into the line of the particle accelerator. The machine was maybe the size of a two-story building, on tracks, with lights and bulbs and dials and scaffolds all around, with men climbing all over it.

Feynman said, "What experiment is this?"

The director said, "Why this is an experiment to test the change-change something-or-other under such-and-such circumstances." But he stopped suddenly, and he said, "I forgot! This is your theory of change-change, Dr. Feynman! This is an experiment to demonstrate, if we can, your theory of fifteen years ago, called so-and-so." He was a little embarrassed at having forgotten it.

Feynman looked at this big machine, and he said, "How much does this cost?" The man said, "Thirty-seven million dollars," or whatever it was.

And Feynman said, "You don't trust me?"

-- excerpted from "No Ordinary Genius" by Christopher Sykes

⬐ GuyC

Why? http://www.youtube.com/watch?v=MO0r930Sn_8&NR=1

⬐ dazzawazza

You can see better quality feynman here in the BBC archives: http://www.bbc.co.uk/archive/feynman/

It maybe for brits only though... I'm sure there are ways around that.

⬐ boredguy8

"I've got to stop somewhere, and leave you something to imagine <giggle>."

A humbling exhortation, if ever there was one.

I loved reading his lectures (as opposed to the classes I was in) because he was interested in getting to the 'what's going on', not the 'here's the equation to know.' One of his autobiographies talks about his frustration in this area when he was talking about polarized light at a university outside the US. They had spent all day talking about polarized light in the classroom, but nobody could predict or explain what was going on when he took two polarized filters and stacked & rotated them.

http://www.youtube.com/watch?v=MO0r930Sn_8

That's a phenomenal video of him explaining how to ask questions. And does a great job explaining that, "Why?" questions aren't very good questions, without a context. And goes from there to 'everyday QED' with elegance and grace.

⬐ BobbyH

Feynman's explanation of where a tree gets its mass starts here: http://www.youtube.com/watch?v=N1pIYI5JQLE#t=2m12s

⬐ joubert

Without detracting from Feynman's genius, it is striking how simple physics is in comparison to biology.

⬐ SMrF

Biology is just a layer of abstraction on top of physics. It's turtles all the way down...

⬐ joubert

what do you mean?

⬐ jleard

Turtles all the way down: http://en.wikipedia.org/wiki/Turtles_all_the_way_down

Fields arranged by purity: http://xkcd.com/435/

⬐ joubert

Where does evolution by natural selection fit into that xkcd:Purity sketch?

⬐ vermontdevil

Wish these videos were captioned.

⬐ mkramlich

Thankfully since we've captured parts of Feynman in the form of writing, audio and video, even though he has died he will in all likelihood be teaching people for centuries more into the future. How awesome is that.

⬐ zackattack

The sound is too low for me to hear. Anyone know a cool trick to make things louder? I'm using Leopard.

⬐ kleevr

Uh, I wouldn't know about Leopard; but Ubuntu can apparently go to "11". (http://i.imgur.com/8E7Wx.jpg)

⬐ dnsworks

They go to tree church on Sunday, duh.

⬐ drawkbox

I have seen this many times but it never gets old. I wish the Feynman style of teaching and explaining our amazing world were more available. His physics lectures are now available but kids would be extremely anxious to learn if teachers made basic science as fun as Feynman did. He was smart to tune his way of talking so his audience would understand no matter their level of knowledge (i.e. "jiggly motion" describing heated atoms).

I am hoping that the internet and such things as OpenCourseware will allow college professors, teachers and more to become stars of teaching because they know how to communicate and make it fun.

These people should be compensated much more and be seen by many more people such as MIT's Walter Lewin, Feynman and many many others hidden in the fold of our current traditional education systems.

⬐ blaix

I loved how he explained the strange attracting/repelling nature of carbon and oxygen as a ball rolling uphill to get to a hole. So simple yet so brilliant.

⬐ zargon

anxious, adj., 1. Uneasy and apprehensive about an uncertain event or matter; worried

You probably meant 'eager.'

⬐ thaumaturgy

3. Ardently or earnestly wishing. e.g., "anxious to learn more".

Also, please don't do that here. :-)

⬐ sliverstorm

It's not just his style, but how animated and excited he gets when he's talking about these things!

⬐ patrickk

That's because he's so passionate about the subject matter.

I gave up studying physics in secondary school because my teacher was a disaster. Instead of trying to impart a deeper understanding of the subject matter in question, he would focus on getting student to learn off scientific definitions word for word (i.e. having all the "ands", "ats", "is'", "the's" in the correct place). So you would have a textbook answer memorized for the test (perhaps), but sweet fuck all actual knowledge of physics.

To see this kind of passion is refreshing, and the way things should be. (If you've ever seen 'The Wire', seasons 4 & 5 have 'Mr. Prezbo' teaching maths. He struggles to connect with his student until he teaches them how to apply probability theory to dice games, allowing them to gamble more effectively. Unfortunately for him, he also has to 'teach to the test' so that the school can say standardised test scores are going up).

⬐ dantheman

Agreed, Enthusiasm and Passion are contagious -- when someone cares deeply about something it's hard not be interested.

⬐ dkersten

When I was studying for my degree, my favourite course was "Digital Signal Processing" and I'm pretty sure it was because the lecturer was genuinely interested and enthusiastic about the subject. Enthusiasm is very contagious and hard to resist. I think everyone in that course liked it and found it easy to learn, just because we had a teacher who was really enthusiastic about what he was teaching. If only everyone was like this...

⬐ Tiktaalik

I agree it's the passion. I had a chemistry teacher in highschool that was equally as passionate about chemistry as Feynman is here and it really helped me learn the subject.

⬐ blaix

You can really tell how much he loves the subject matter. Get the feeling he could just keep talking about it all day if you let him.

I'd let him.