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Reality has a surprising amount of detail (2017)

johnsalvatier.org

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Re: Reality has a surprising amount of detail (2017)

#171

Post by dkarl »

larrik wrote: post #98

I've actually built a few staircases, and it's a ton harder than it even sounds here. In fact, there's apparently carpentry competitions and building a stairway to code is the grand finale. The way he does it, with the angle brackets? That's the easiest way, and by far the weakest. The strongest way is to notch out 2x12's (ideally at least 3, with one in the middle). Oh, and no step can be more than 1/8" difference i…

A dirty secret (?) is that a lot of the stairways you encounter are not built to code, either because they were built before current codes were put into place or because they were modified after inspection. A common practice is for certain required elements to be included in a way that makes them easy to remove. My girlfriend pointed out an instance of that to me recently — if you looked closely you could see that a handrail (the round bar you can hold onto while you walk on the stairs) had been mounted to the guardrail (the panel that makes it impossible to fall off the stairs sideways) and then removed. She said it was probably added to pass inspection because the guardrail, which was a very beautiful metal design, did not technically qualify as a handrail. Either the stairs failed inspection and the contractor temporarily fixed it up by adding the handrail, or more likely, the designer anticipated the inspection issue and included a cheap handrail for the owner (or more likely the contractor) to remove after inspection. Some people welcome the challenge of designing to code, but some people just resent it and circumvent it whenever they can.

Re: Reality has a surprising amount of detail (2017)

#172

Post by gwbas1c »

I can't begin to count the number of times I've worked with an idea person who can't comprehend the details; or a product manager who can't work through high-level corner cases and expects that the computer can read his mind.

This is a good read for either of those kinds of people.

Re: Reality has a surprising amount of detail (2017)

#173

Post by beat »

jasode wrote: post #53

>Do you remember the insights that were crucial in learning to ride a bike or drive? The author mentioned bicycles and inadvertently missed an opportunity to show another "unknown reality" that beautifully illustrates his point. Consider typical adults (not physicists) with 20+ years of bicycle riding. If you ask them, "how does a bicycle turn?" , they'd respond that "you just lean into the direction of the turn and…

For guitar nerds, there's a whole online business by a guy named Troy Grady about fast picking techniques (he has a ton of extremely polished videos on YouTube - start with whatever "Cracking the Code" videos are up). He decoded the seemingly-magical techniques that allow players like Yngwie Malmsteen and Eric Johnson to play at what feel like impossible speeds, and illustrates them. (tl;dr the core trick is "pick slanting", striking the strings at an angle so the pick goes in and out of the plane of strings, rather than across it, and then switching strings only when the pick is "out". That, and "chunking", breaking into units of fixed length on a single string and using the fixed length to do a clock reset on the beats).

For a guitarist, it's almost impossible to explain the myriad tiny details that go into something as seemingly simple as picking a note. Troy's analysis of instructional videos by great players, where they obviously don't understand what they're doing, is kind of amazing. And a real eye-opener, for those of us who have played a long time.

Re: Reality has a surprising amount of detail (2017)

#174

Post by twothamendment »

larrik wrote: post #98

I've actually built a few staircases, and it's a ton harder than it even sounds here. In fact, there's apparently carpentry competitions and building a stairway to code is the grand finale. The way he does it, with the angle brackets? That's the easiest way, and by far the weakest. The strongest way is to notch out 2x12's (ideally at least 3, with one in the middle). Oh, and no step can be more than 1/8" difference i…

Don't forget stairs that land on surface that is sloped from one side of the stairs to the other. What height should that bottom step be? Will the inspector measure both sides? Do you shoot for the middle being right on and each side being a bit too high and a bit too low?

Watch the height on the first and last steps. The middle ones are the "easy" ones.

In bigger cities there are companies that only frame stairs. It is amazing to watch them - they can do it in their sleep. I watched one crew finish up some complex stairs in less time than our framing crew would have spent making a game plan.

There is detail in everything and until you've done that job you really don't notice it.

Re: Reality has a surprising amount of detail (2017)

#175

Post by Johnny555 »

le-mark wrote: post #127
sly010 wrote: post #117

A few years ago I co-founded a standing desk company without any experience in real world products in general. The plan was to source desks and sell them to companies. How complicated could it be? Well, the freight company requires a lot of information about the destination building. The destination building require a lot of paperwork in a very specific format just to deliver something. The paperwork is always a litt…

If you're like my old boss, just tell the employees to assemble their own desks, and then wonder why all these developers who requested a standing desk, are still using their old sit down desks.

I'd be happy to assemble all of my office furniture if my company paid for it -- though paying $100+/hour engineers to do the work of a $15+ handyman seems like a bad deal for the company - especially when the guy that assembles desks all day will do it faster (and correctly).

Re: Reality has a surprising amount of detail (2017)

#176

Post by nlawalker »

This is such a good explanation of why I have a hard time working with folks who always approach technical problems with the attitude of "why don't we just do this?"

It's the just that gets me. They are too action-oriented to think about the details or ask someone who's done it before, so they start down the path of (to use the author's metaphor) buying cheap lumber and calculating the angles for cutting the stair boards. They follow through with that and finish the rest of the stairs with the same attitude.

Now the stairs are finished and installed (shipped) - they look terrible, they're wobbly and too steep and everyone who walks on them in either direction trips. Then begins the never-ending process of in-place improvements: using a sander to even out the angles, grinding down the too-long screws that stick up, pounding on warped boards to straighten them out. We can't fix the angle or the poor spacing of the steps though, because everyone's gotten perversely used to it.

When the whole house gets built this way, you live in a perpetual fixer-upper, where each component is either under revision or you've settled for it being "good enough" until enough work has been done to make everything else a little less broken.

Re: Reality has a surprising amount of detail (2017)

#177

Post by logfromblammo »

mojuba wrote: post #44

Two things that came to mind while reading this essay: - The effect of a surprise when facing unexpected complications/details is because our brains tend to simplify things, or rather simplify the model of the world that we maintain. When you first hear that water boils at 100º your brain really really wants to assume it's that simple, no more than that. Simplifications are crucial for optimising the brain's power co…

Pure water boils at 100 ºC, in an environment at standard temperature and pressure, with sufficient vapor bubble nucleation sites.

If you're a cook, you don't really need to know all that, because you either live up in the mountains (at lower pressure) or you don't. You either have hard water (with more dissolved ions) or you don't. And your pots are never scrubbed perfectly clean.

Suppose that in a few centuries, stairs will have to account for different numbers of legs, or wheels, or different foot types, or varying amounts of gravity, or track gauge, or crystal habit, or effect on convection and ventilation, or whether classical Earth-standard humans will ever be expected to use them.

Re: Reality has a surprising amount of detail (2017)

#178

Post by 24gttghh »

dingo_bat wrote: post #104
littlestymaar wrote: post #76

Earlier quoted context omitted.

> If one human is teaching another human, you can leave the "countersteering" detail out and it won't matter. The 200 years of people learning how to ride bicycles is evidence of that. This is actually a well-known fact about motorcycle, and it's taught in driving schools. It's just that their is no bicycle driving school and people just figure it by themselves. I'm pretty sure it takes more time though.

I don't think regular driving schools teach you to countersteer when you turn.

Perhaps they mean riding schools as any MSF endorsed riders course will teach you to counter-steer to initiate a turn [0] at higher speeds. It is especially important on a motorcycle due to the forces/speeds involved.

[0]http://www.msf-usa.org/downloads/BRCHandbook.pdf (sec.4, pg.8)

Re: Reality has a surprising amount of detail (2017)

#179

Post by dekhn »

appearsonline wrote: post #167
mikepalmer wrote: post #130

Earlier quoted context omitted.

And... what are the huge implications??

Come on dekhn, we want to know

OK, sure. One of the most interesting long-running issues in proteins is how they adopt their 3D structure and remain stable for such long periods.

Most people would say that covalent bonds hold the protein together and they dominate the overall structure- for example, you wouldn't ever see a strained covalent bond, so you can easily eliminate all structures with strained bonds. This was long an assumption. However, work I did at Google using Exacycle demonstrated that, in fact, large collections of hydrogen bonds can in fact work in concert to stabilize proteins with strained covalent bonds (http://onlinelibrary.wiley.com/doi/10.1002/pro.2389/full), which overturned the assumption, and made a modest contribution to the prediction of protein folds, and protein design.

Re: Reality has a surprising amount of detail (2017)

#180

Post by loco5niner »

le-mark wrote: post #127
sly010 wrote: post #117

A few years ago I co-founded a standing desk company without any experience in real world products in general. The plan was to source desks and sell them to companies. How complicated could it be? Well, the freight company requires a lot of information about the destination building. The destination building require a lot of paperwork in a very specific format just to deliver something. The paperwork is always a litt…

If you're like my old boss, just tell the employees to assemble their own desks, and then wonder why all these developers who requested a standing desk, are still using their old sit down desks.

I would love to do that.
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