# Tag: MIT

## Quantum Dollars use Uncertainty to Create Certainty

By Eric Wolff | December 13, 2010 4:29 am

Without getting into the ethics of WikiLeak’s activities, I’m disturbed that Visa, MasterCard and PayPal have all seen fit to police the organization by refusing to act as a middleman for donations.  The whole affair drives home how dependent we are on a few corporations to make e-commerce function, and how little those corporations guarantee us anything in the way of rights.

In the short term, we may be stuck, but in the longer term, quantum money could help solve the problems by providing a secure currency that can be used without resort to a broker.

Physicist Steve Wiesner first proposed the concept of quantum money in 1969. He realized that since quantum states can’t be copied, their existence opens the door to unforgeable money.

Here’s how MIT computer scientist Scott Aaronson explained the principles:

Heisenberg’s famous Uncertainty Principle says you can either measure the position of a particle or its momentum, but not both to unlimited accuracy. One consequence of the Uncertainty Principle is the so-called No-Cloning Theorem: there can be no “subatomic Xerox machine” that takes an unknown particle, and spits out two particles with exactly the same position and momentum as the original one (except, say, that one particle is two inches to the left). For if such a machine existed, then we could determine both the position and momentum of the original particle—by measuring the position of one “Xerox copy” and the momentum of the other copy. But that would violate the Uncertainty Principle.

…Besides an ordinary serial number, each dollar bill would contain (say) a few hundred photons, which the central bank “polarized” in random directions when it issued the bill. (Let’s leave the engineering details to later!) The bank, in a massive database, remembers the polarization of every photon on every bill ever issued. If you ever want to verify that a bill is genuine, you just take it to the bank”

CATEGORIZED UNDER: Computers, Electronics

## It's a Bird! It's a Plane! It's…Yeah, It's a Plane.

By Eric Wolff | November 22, 2010 4:00 am

Rarely in our visions of the future do people have to make long landings, or fly on commercial jet liners. Seems like they’ve always advanced past that.

Here in the present, we don’t seem to be making much headway in really crazy transportation breakthroughs — not much sign of beaming or stargates — but some scientists are considering some novel ways to improve air travel by copying our friends the birds.

OK, maybe “friends” is a little strong for describing our relationship to the last living dinosaurs, but nonetheless, with the ability to hover, stop on a dime, and fly with impressive energy efficiency, birds offer researchers a great deal of inspiration for improving aircraft.

At the 63rd Annual Meeting of the APS Division of Fluid Dynamics in Long Beach, Calif. Last weekend, Geoffrey Spedding of the University of Southern California and Joachim Huyssen of Northwestern University in South Africa presented research offering a more birdlike wing and tail design that could reduce drag and therefore improve efficiency.

CATEGORIZED UNDER: Transportation

## If the Cylons made solar panels, the panels would assemble themselves

By Eric Wolff | September 10, 2010 9:00 am

In the fifth season of Battlestar Galactica, the Cylons gave the Galactica a kind of spray-on bacteria that could make the walls self-healing. Any race of beings that cold make that work out would surely have commercialized something like the work of MIT researcher Michael Strano who have devised tiny solar-electric generators that can break apart and reassemble. The team published their efforts in Nature Chemistry.

The research solves a significant problem in the shift toward solar power, that of degradation. Even silicon solar panels lose efficiency over time as solar radiation breaks down its components. Yet plants don’t have this problem: they use sugar and minerals to constantly refresh their photosynthetic cells, e.g. leaves. Strano and his colleagues looked at how leaves work to develop their tiny solar generators. Using seven different chemicals the generators will self assemble, even after they’ve broken down, and with no loss of efficiency.

The basic unit requires a synthetic phospholipids, which itself is just a plate to hold the chemicals that react to light. These chemicals release electrons when photons hit them. The phospholipid plates are themselves attracted to carbon nanotoubes. The tubes, which are highly conductive, are lined up in long rows forming a wire to carry the electrons to their destination.

But even through the reaction is 40 percent efficient —- more efficient than standard thin film photovoltaic cells, which capture about 28 percent of sunlight —— that’s not even the impressive part. When the system is damaged, as sunlight is wont to do to solar panels, it will reassemble itself. Strano and his team broke down the system again and again over a 14-hour period and the system consistently put itself back together again with no loss of efficiency.

Take that Cylon Model 6. The humans will have self-assembly without your help.

(picture courtesy of PR Web)

CATEGORIZED UNDER: Energy, Nanotech

## Stargate Atlantis Gets Biomechanical

By Stephen Cass | July 22, 2008 5:18 pm

On the last episode of Stargate Atlantis, several of the characters were accidentally infected with an unusual pathogen: one that reprograms their bodies to begin the first stage of the process used to construct a Wraith starship. Wraith starships are biomechanical, that is they are made from organic, semi-alive materials rather than built out of metal, rubber and other more familiar materials. In fact Wraith ships aren’t really built at all — as the episode demonstrates, they’re grown.

In the real world, we’re actually making progress on what could be the distant ancestor of this technology. At places like Brown University, MIT, and Berkeley researchers are working on synthetic biology: the goal is to reprogram the DNA of microbes so that they can be used to construct minature machines, or act as tiny computers to process information. (A special shout out to DISCOVER’s 2006 Scientist of the Year, Jay Keasling.) There is even a contest — The International Genetically Engineered Machine competition — hosted by MIT. Teams of students use a library of standard “parts” (genetic sequences that perform specific fuctions) known as BioBricks to make their creations. Winners of this year’s competition will be announced in November.

CATEGORIZED UNDER: Apocalypse, Biotech, TV
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