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Comment by crocowhile | Hacker News Reader

Yes, I haven't read the other comments but that is a terrible terrible explanation. OP had a genuine question about the nature of things and the person answered bringing up paper and arrows. This is the stuff that made Feynmann mad when they asked him about magnets.

The only reasonable answer to the original question is: we don't know. The whole schizofrenic theory of something that can be waves and particles doesn't make sense right now but that's the best we can come up with. Nothing can go faster than light because our equations tell us so but we don't know the mechanisms, exactly as we don't know what is creating gravity, for instance. Physics is full of deep mysteries still.

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Have you ever read the book QED? It's Feynman's best effort to explain Quantum Electrodynamics to a layman. In the book, he takes a genuine question about the nature of things (how does light work?) and answers it by "bringing up paper and arrows!" (I encourage you to read the book to see what I mean). Feynman disliked "explaining" nature with inaccurate and irresponsible metaphors. But arrows are the way it really is!

I haven't read that particular book. I pointed out Feynman's magnets because they were a bit of a recurring joke on reddit (I refuse to use the word meme) and found ironic redditors fell in the same trap.

On a margin note, the best book I've read about explaining modern physics to the layman is this: http://www.amazon.com/Evolution-Physics-Albert-Einstein/dp/0...

What's wrong with the word meme? It wasn't invented by reddit, you know (or 4chan either).

For anyone unaware, "meme" was coined by Richard Dawkins in The Selfish Gene in 1976.

Yeah, I believe he proved a correspondence between the arrows and the Schroedinger equation (not in that book) at some point (and it's not hard to come up with a character of the proof). The grandparent is referring to something like this video, though, which you mentioned at the end: http://www.youtube.com/watch?v=wMFPe-DwULM

Bringing in arrows where they don't belong, or in the magnet case "rubber bands", is cheating the asker. I'm not familiar enough with GR to know if arrows are a useful representation like they are with complex amplitudes.

There's also this video of him telling his students that there's no simple, philosophically pleasing way to explain the world. It just is how it is.

http://www.youtube.com/watch?v=iMDTcMD6pOw

It's often more helpful to explain why things work in terms of the physics we understand right now that not at all. Sure, it's dissatisfying to hear "the arrows can't stretch because that's the way it is", but it's a useful metaphor that can help explain time dilation and why we can't go faster than light. Physics answers often end up with "because that's the way it is", but that doesn't mean that the things you've learned up until then are useless.

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