Monthly Archives: January 2013

Stories From New Guinea

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Tales From the World Before Yesterday: A Conversation with Jared Diamond

[A]s I got more experienced in New Guinea, I realized, every night I sleep out in New Guinea forest. At some time during the night, I hear the sound of a tree crashing down. And, you see tree falls in New Guinea forest, and I started to do the numbers. Suppose the chances of a dead tree crashing down on you the particular night that you sleep under it is only one in 1,000. But suppose you’re a New Guinean, who’s going to sleep every night in the forest, or spend 100 nights a year sleeping out in the forest. In the course of 10 years, you will have spent a thousand nights in the forest, and if you camp under dead trees, and each dead tree has a one in 1,000 chance of falling on you and killing you, you’re not going to die the first night, but in the course of 10 years, the odds are that you are going to die from sleeping under dead trees. If you’re going to do something repeatedly that each time has a very low chance of bringing disaster. But if you’re going to do it repeatedly, it will eventually catch up with you.

That incident affected me more than anything else, because I realized that in life, we encounter risks that each time the risk is very slight. But if you’re going to do it repeatedly, it will catch up with you.

He has a new book out, The World Until Yesterday: What Can We Learn from Traditional Societies? which, given his prior work, I will probably read at some point.

A Liter of Light

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An Innovative and Cheap ‘Solar Bottle Bulb’ Solution Lights Homes in Manila

This is a really neat solution to the problem of dwellings that could really use passive light; it’s not truly an alternative to something like the gravitylight , which is not passive, but for closely-spaced dwellings that don’t have much in the way of window real estate relative to the interior area, and lack (affordable) electricity, it’s just the ticket to light them up during the day.

This is a kind of light pipe (one version of which is a deck prism seen on some boats). I have to think something like this would have been useful for a playhouse when I was a kid. Some more detailed instructions exist, if you are inclined to employ on of these.

How Low Can You Go?

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Here’s a couple of posts on the negative-temperature experiment that was in the news last week:

Uncertain Principles: What Does “Negative Temperature” Mean, Anyway?

Built on Facts: Less Than Absolute Zero

The upshot of all this is that many of the stories were generally over-hyping the negative temperature aspect of the experiment, some to the point of simply getting it wrong that somehow this was a new and earth-shattering result. A spin system was put into a negative temperature state way back in the early 1950’s, and (as Matt points out) lasers have population inversions in them as well. One should note that you don’t get these negative temperatures via straightforward thermodynamic means — you have to rig the system to do so, meaning they don’t happen spontaneously.

Banished Balls

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Forbidden spheres

Imagine the scenario: you’re a security officer working at Los Alamos. You know that spheres are weapon parts. You walk into a technical area, and you see spheres all around! Is that an ashtray, or it is a model of a plutonium pit? Anxiety mounts — does the ashtray go into a safe at the end of the day, or does it stay out on the desk? (Has someone been tapping their cigarettes out into the pit model?)

All of this anxiety can be gone — gone! — by simply banning all non-nuclear spheres! That way you can effectively treat all spheres as sensitive shapes.

I find this to be an interesting problem — simplifying the task so that someone without the technical skills can make a determination about security. It’s frustrating from the vantage point of the scientist, especially because secrecy tends to run counter to our desire to share our work (an important step in advancing an idea) and also because of the observation about secrecy being contagious, like a disease.

I encountered this when I was in the navy. We had some relatively low-level classified material, from a technical standpoint, and all of it was stamped in red ink and stored in red folders. Security — comprised mostly of students-in-waiting, led by a few permanent staff, only had to have a “see red” mentality, rather than any training on whether a sheet of paper was a set of classified specs or a shopping list. I doubt at Los Alamos that the low-level guards worried about whether spheres were research parts — they had just been told that all spheres were a violation.

Look at the reverse, though. We try and classify things ourselves, and that can have a bad end when it comes to security. Take the incidents a few years ago in Boston involving flashy and/or colored lights. The “bomb” finders caused panic, simply because they had a mental image that objects with flashy lights are what bombs look like.

Pick a Peck of Pockets

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A Pickpocket’s Tale

He is probably best known for an encounter with Jimmy Carter’s Secret Service detail in 2001. While Carter was at dinner, Robbins struck up a conversation with several of his Secret Service men. Within a few minutes, he had emptied the agents’ pockets of pretty much everything but their guns. Robbins brandished a copy of Carter’s itinerary, and when an agent snatched it back he said, “You don’t have the authorization to see that!” When the agent felt for his badge, Robbins produced it and handed it back. Then he turned to the head of the detail and handed him his watch, his badge, and the keys to the Carter motorcade.