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Richard Feynman and the Connection Machine

Danny Hillis is best known for his Connection Machine, a massively parallel supercomputer that led to breakthroughs in computational science and parallel computing. (It also was the subject of Hillis's book The Connection Machine, which was a highly technical but fascinating version of his thesis paper on parallel computing. If you want the only halfway mind-blowing version, check out The Pattern on the Stone.) Hillis later led R&D at Walt Disney Imagineering, but in my book the Connection Machine was his awesomest project.

The Connection Machine was actually a series of supercomputers, labeled CM-1, CM-2, and so on. A CM-5 (codenamed FROSTBURG) is pictured above left -- originally installed at the National Security Agency, it was used to break codes and is now on display at the National Cryptologic Museum. Looking surprisingly like a classic "movie computer" (one did appear in Jurassic Park), the CM-5 was covered in blinky lights that communicated the status of various processing nodes, and could be used in diagnostics. (So they're useful for something after all....)

Anyway, the point of this blog is that Hillis wrote an essay for Physics Today about physicist Richard Feynman's involvement in the Connection Machine's development -- and now the article is available online via The Long Now Foundation. Hillis's article reveals how Feynman was instrumental in designing the Connection Machine's router, which was key in distributing communications within the massive machine. From the article:

Richard's interest in computing went back to his days at Los Alamos, where he supervised the "computers," that is, the people who operated the mechanical calculators. There he was instrumental in setting up some of the first plug-programmable tabulating machines for physical simulation....

The router of the Connection Machine was the part of the hardware that allowed the processors to communicate. It was a complicated device; by comparison, the processors themselves were simple. Connecting a separate communication wire between each pair of processors was impractical since a million processors would require $10^{12]$ wires. Instead, we planned to connect the processors in a 20-dimensional hypercube so that each processor would only need to talk to 20 others directly. Because many processors had to communicate simultaneously, many messages would contend for the same wires. The router's job was to find a free path through this 20-dimensional traffic jam or, if it couldn't, to hold onto the message in a buffer until a path became free. Our question to Richard Feynman was whether we had allowed enough buffers for the router to operate efficiently.

Read the rest if you're interested in Feynman, math, blinky lights, or just crazy engineering projects. See also: more on the Connection Machine, more on Danny Hillis.

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The Prehistoric Bacteria That Helped Create Our Cells Billions of Years Ago
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We owe the existence of our cells—the very building blocks of life—to a chance relationship between bacteria that occurred more than 2 billion years ago. Flash back to Bio 101, and you might remember that humans, plants, and animals have complex eukaryotic cells, with nucleus-bound DNA, instead of single-celled prokaryotic cells. These contain specialized organelles such as the mitochondria—the cell’s powerhouse—and the chloroplast, which converts sunlight into sugar in plants.

Mitochondria and chloroplasts both look and behave a lot like bacteria, and they also share similar genes. This isn’t a coincidence: Scientists believe these specialized cell subunits are descendants of free-living prehistoric bacteria that somehow merged together to form one. Over time, they became part of our basic biological units—and you can learn how by watching PBS Eons’s latest video below.

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Stones, Bones, and Wrecks
Buckingham Palace Was Built With Jurassic Fossils, Scientists Find
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The UK's Buckingham Palace is a vestige from another era, and not just because it was built in the early 18th century. According to a new study, the limestone used to construct it is filled with the fossilized remains of microbes from the Jurassic period of 200 million years ago, as The Telegraph reports.

The palace is made of oolitic limestone, which consists of individual balls of carbonate sediment called ooids. The material is strong but lightweight, and is found worldwide. Jurassic oolite has been used to construct numerous famous buildings, from those in the British city of Bath to the Empire State Building and the Pentagon.

A new study from Australian National University published in Scientific Reports found that the spherical ooids in Buckingham Palace's walls are made up of layers and layers of mineralized microbes. Inspired by a mathematical model from the 1970s for predicting the growth of brain tumors, the researchers created a model that explains how ooids are created and predicts the factors that limit their ultimate size.

A hand holding a chunk of oolite limestone
Australian National University

They found that the mineralization of the microbes forms the central core of the ooid, and the layers of sediment that gather around that core feed those microbes until the nutrients can no longer reach the core from the outermost layer.

This contrasts with previous research on how ooids form, which hypothesized that they are the result of sediment gathered from rolling on the ocean floor. It also reshapes how we think about the buildings made out of oolitic limestone from this period. Next time you look up at the Empire State Building or Buckingham Palace, thank the ancient microbes.

[h/t The Telegraph]

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