kottke.org posts about computing
Google and NASA recently bought a D-Wave quantum computer. But according to a piece by Sophie Bushwick published on the Physics Buzz Blog, there isn't scientific consensus on whether the computer is actually using quantum effects to calculate.
In theory, quantum computers can perform calculations far faster than their classical counterparts to solve incredibly complex problems. They do this by storing information in quantum bits, or qubits.
At any given moment, each of a classical computer's bits can only be in an "on" or an "off" state. They exist inside conventional electronic circuits, which follow the 19th-century rules of classical physics. A qubit, on the other hand, can be created with an electron, or inside a superconducting loop. Obeying the counterintuitive logic of quantum mechanics, a qubit can act as if it's "on" and "off" simultaneously. It can also become tightly linked to the state of its fellow qubits, a situation called entanglement. These are two of the unusual properties that enable quantum computers to test multiple solutions at the same time.
But in practice, a physical quantum computer is incredibly difficult to run. Entanglement is delicate, and very easily disrupted by outside influences. Add more qubits to increase the device's calculating power, and it becomes more difficult to maintain entanglement.
(via fine structure)
Google's got themselves a quantum computer (they're sharing it with NASA) and they made a little video about it:
I'm sure that Hartmut is a smart guy and all, but he's got a promising career as an Arnold Schwarzenegger impersonator hanging out there if the whole Google thing doesn't work out.
A 30-minute documentary from the 60s on the Apollo Guidance Computer.
I will read stories about Richard Feynman all day long and this one is no exception. Danny Hillis remembers his friend and colleague in this piece originally written for Physics Today (original here).
Richard arrived in Boston the day after the company was incorporated. We had been busy raising the money, finding a place to rent, issuing stock, etc. We set up in an old mansion just outside of the city, and when Richard showed up we were still recovering from the shock of having the first few million dollars in the bank. No one had thought about anything technical for several months. We were arguing about what the name of the company should be when Richard walked in, saluted, and said, "Richard Feynman reporting for duty. OK, boss, what's my assignment?" The assembled group of not-quite-graduated MIT students was astounded.
After a hurried private discussion ("I don't know, you hired him..."), we informed Richard that his assignment would be to advise on the application of parallel processing to scientific problems.
"That sounds like a bunch of baloney," he said. "Give me something real to do."
So we sent him out to buy some office supplies. While he was gone, we decided that the part of the machine that we were most worried about was the router that delivered messages from one processor to another. We were not sure that our design was going to work. When Richard returned from buying pencils, we gave him the assignment of analyzing the router.
For more Hillis, I recommend Pattern on the Stone and for more Feynman, you can't go wrong with Gleick's Genius.
As recently as last year, a liquid filtration company in Texas was still using a computer built in 1948 to run all of its accounting work.
Sparkler's IBM 402 is not a traditional computer, but an automated electromechanical tabulator that can be programmed (or more accurately, wired) to print out certain results based on values encoded into stacks of 80-column Hollerith-type punched cards.
Companies traditionally used the 402 for accounting, since the machine could take a long list of numbers, add them up, and print a detailed written report. In a sense, you could consider it a 3000-pound spreadsheet machine. That's exactly how Sparkler Filters uses its IBM 402, which could very well be the last fully operational 402 on the planet. As it has for over half a century, the firm still runs all of its accounting work (payroll, sales, and inventory) through the IBM 402. The machine prints out reports on wide, tractor-fed paper.
Here's what one of the computer's apps look like:
Objects in motion tends to stay in motion.
In 2003, British philosopher Nick Bostrom suggested that we might live in a computer simulation. From the abstract of Bostrom's paper:
This paper argues that at least one of the following propositions is true: (1) the human species is very likely to go extinct before reaching a "posthuman" stage; (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof); (3) we are almost certainly living in a computer simulation. It follows that the belief that there is a significant chance that we will one day become posthumans who run ancestor-simulations is false, unless we are currently living in a simulation. A number of other consequences of this result are also discussed.
The gist appears to be that if The Matrix is possible, someone has probably already invented it and we're in it. Which, you know, whoa.
But researchers believe they have devised a test to check if we're living in a computer simulation.
However, Savage said, there are signatures of resource constraints in present-day simulations that are likely to exist as well in simulations in the distant future, including the imprint of an underlying lattice if one is used to model the space-time continuum.
The supercomputers performing lattice quantum chromodynamics calculations essentially divide space-time into a four-dimensional grid. That allows researchers to examine what is called the strong force, one of the four fundamental forces of nature and the one that binds subatomic particles called quarks and gluons together into neutrons and protons at the core of atoms.
"If you make the simulations big enough, something like our universe should emerge," Savage said. Then it would be a matter of looking for a "signature" in our universe that has an analog in the current small-scale simulations.
If it turns out we're all really living in an episode of St. Elsewhere, I'm going to be really bummed. (via @CharlesCMann)
I'm going to link again to Errol Morris' piece on his brother's role in the invention of email...the final part was posted a few hours ago...the entire piece is well worth a read. As is the case with many of his movies, Morris uses the story of a key or unique individual to paint a broader picture; in this instance, as the story of his brother's involvement with an early email system unfolds, we also learn about the beginnings of social computing.
Fernando Corbato: Back in the early '60s, computers were getting bigger. And were expensive. So people resorted to a scheme called batch processing. It was like taking your clothes to the laundromat. You'd take your job in, and leave it in the input bins. The staff people would prerecord it onto these magnetic tapes. The magnetic tapes would be run by the computer. And then, the output would be printed. This cycle would take at best, several hours, or at worst, 24 hours. And it was maddening, because when you're working on a complicated program, you can make a trivial slip-up - you left out a comma or something - and the program would crash. It was maddening. People are not perfect. You would try very hard to be careful, but you didn't always make it. You'd design a program. You'd program it. And then you'd have to debug it and get it to work right. A process that could take, literally, a week, weeks, months -
People began to advocate a different tactic, which came to be called time-sharing. Take advantage of the speed of the computer and have people at typewriter-like terminals. In principle, it seemed like a good idea. It certainly seemed feasible. But no manufacturer knew how to do it. And the vendors were not terribly interested, because it was like suggesting to an automobile manufacturer that they go into the airplane business. It just was a new game. A group of us began to create experimental versions of time-sharing, to see if it was feasible. I was lucky enough to be in a position to try to do this at MIT. And we basically created the "Compatible Time Sharing System," nicknamed CTSS from the initials, that worked on the large mainframes that IBM was producing. First it was going to be just a demo. And then, it kept escalating. Time-sharing caught the attention of a few visionary people, like Licklider, then at BBN, who picked up the mantle. He went to Washington to become part of one of the funding agencies, namely ARPA. ARPA has changed names back and forth from DARPA to ARPA. But it's always the same thing.
And it was this shift from batch processing to time-sharing that accidentally kickstarted people using computers in a social way...programming together, sending notes to each other, etc.
Robert Fano: Yes, the computer was connected through telephone lines to terminals. We had terminals all over the MIT campus. People could also use CTSS from other locations through the teletype network. CTSS was capable of serving about 20 people at a time without their being aware of one another. But they could also communicate with each other. A whole different view of computers was generated.
Before CTSS, people wrote programs for themselves. The idea of writing programs for somebody else to use was totally alien. With CTSS, programs and data stored could be stored in the common memory segment and they were available to the whole community. And that really took off. At a certain point, I started seeing the whole thing as a system that included the knowledge of the community. It was a completely new view. It was a remarkable event. In retrospect, I wish I had gotten a very smart social psychologist on the premises to look at and interpret what was happening to the community, because it was just unbelievable.
There was a community of people using the computer. They got to know each other through it. You could send an e-mail to somebody through the system. It was a completely new phenomenon.
It seems completely nutty to me that people using computers together -- which is probably 100% of what people use computers for today (email, Twitter, Facebook, IM, etc.) -- was an accidental byproduct of a system designed to let a lot of people use the same computer separately. Just goes to show, technology and invention works in unexpected ways sometimes...and just as "nature finds a way" in Jurassic Park, "social finds a way" with technology.
This James Fallows article from the July 1982 issue of The Atlantic Monthly is a wonderful technological time capsule. Fallows purchased a PC early in the 80s for use as a word processor.
For a while, I was a little worried about what they would come up with, especially after my father-in-law called to ask how important it was that I be able to use both upper- and lower-case letters. But finally, for a total of about $4,000, Optek gave me the machinery I have used happily to this day.
In the early days of personal computing, there were many competing machines, processors, operating systems manufactured by a number of companies. The PC Fallows bought was a crazy-quilt of a machine -- the monitor was made by Ball Corporation (the canning supplies company) and the printer was a converted IBM Selectric typewriter -- and was soon obsolete.
If I had guessed right, my brand, the Processor Technology SOL, would have caught on, and today I'd have the equivalent of a Mercedes-Benz instead of a Hupmobile. I'd be able to buy new programs at the computer store, and I'd be able to plug in to all the over-the-phone services. But I guessed wrong, and I'm left with a specimen of an extinct breed. When I need new programs, I try to write them myself, and when I have a breakdown, I call the neighborhood craftsman, Leland Mull, who lovingly tends the dwindling local population of SOL-20s.
One of the big bummers about quantum computing is the cold temperatures required (hundreds of degrees below zero). However, a number of researchers believe that certain algae and bacteria perform quantum calculations at room temperature.
The evidence comes from a study of how energy travels across the light-harvesting molecules involved in photosynthesis. The work has culminated this week in the extraordinary announcement that these molecules in a marine alga may exploit quantum processes at room temperature to transfer energy without loss. Physicists had previously ruled out quantum processes, arguing that they could not persist for long enough at such temperatures to achieve anything useful.
Scientists have created a really fast bacterial computer that can solve, among other things, a specialized case of the travelling salesman problem.
Programming such a computer is no easy task, however. The researchers coded a simplified version of the problem, using just three cities, by modifying the DNA of Escherichia coli bacteria. The cities were represented by a combination of genes causing the bacteria to glow red or green, and the possible routes between the cities were explored by the random shuffling of DNA. Bacteria producing the correct answer glowed both colours, turning them yellow.
But just as vacuum tube and silicon chip-based computers became capable of more abstract calculations, perhaps the bacteria computer will follow the same developmental trajectory.
In 1962, Arthur C. Clarke was touring Bell Labs when he heard a demonstration of a song sung by an IBM 704 computer programmed by physicist John L. Kelly. The song, the first ever performed by a computer, was called "Daisy Bell", more commonly known as "Bicycle Built for Two" or "Daisy, Daisy". When Clarke collaborated with Stanley Kubrick on 2001: A Space Odyssey, they had HAL sing it while Dave powered him down.
A clip of a 1963 synthesized computer speech demonstration by Bell Labs featuring "Daisy Bell" was included on an album for the First Philadelphia Computer Music Festival. You can listen to it (it's the last track) and the rest of the album at vintagecomputermusic.com. (via mark)
Update: A reader just reminded me that HAL may have been so named because each letter is off by one from IBM, although Arthur C. Clarke denies this. (thx, justin)
Boxes and Arrows has an interview with Adam Greenfield on his new book, Everyware. "Increasingly invisible but present everywhere in our lives, [computing] has moved off the desktop and out into everyday life -- affecting almost every one of us, whether we're entirely aware of it or not."
Khoi Vinh reports on computer technology in Vietnam. They're wired for broadband and Windows still dominates.
The $100 Laptop being designed by the MIT Media Lab was recently unveiled. It's a bright green, has a hand-crank for recharging the battery, flash memory, USB ports, networking, etc. The target audience is children in third-world countries.
George Dyson visits Google on the 60th anniversary of John von Neumann's proposal for a digital computer. A quote from a Googler -- "We are not scanning all those books to be read by people. We are scanning them to be read by an AI." -- highlights a quasi-philosophical question about Google Print...if a book is copied but nobody reads it, has it actually been copied? (Or something like that.)
Interesting rumination on the possibility of flash memory-based computers. "In two years I have a feeling that Jobs will announce an Intel-flash iBook that will be the thinest laptop ever made boasting the best battery life of any current machine".
Biologists are beginning to simulate living things by computer, molecule by molecule. They're starting with E. coli, but they've still got a long way to go.
As We May Think by Vannevar Bush. This influential essay that introduces Bush's Memex concept was published 60 years ago this month.
DataTiles project from Sony Computer Science Laboratories. Watch the movie for how it works...reminds me a bit of the computer systems in Minority Report.
Cringely on the future plans of Microsoft, Apple, and Google. MS is shipping their own PC, Apple is pushing into video on demand, and Google is building a massive supercomputer with the help of their customers.
A History of the GUI. From Vannevar Bush to OS X and XP.
Scientists at Princeton have made a crude computer out of bacteria. Earlier work showed "they could insert DNA into cells to make them behave like digital circuits [and] perform basic mathematical logic. The latest work expands this concept to vast numbers of bacteria responding in concert."