Category Archives: Blog

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Silicon mindslice: artificial brains (still) “ten years away”

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There’s been a rash of coverage on Dr Markram and the IBM-supported Blue Brain project, one of the experiments designed to move us closer to creating a silicon simulation of the animal brain. Blue Brain is currently based on a silicon recreation of a slice of rat cortex, and Markram’s team have observed spontaneous emergent interaction between their artificial neurons which suggest to them that they’re on the right track… though not everyone is quite so sure.

“We’re building the brain from the bottom up, but in silicon,” says Dr. Markram, the leader of Blue Brain, which is powered by a supercomputer provided by International Business Machines Corp. “We want to understand how the brain learns, how it perceives things, how intelligence emerges.”

Blue Brain is controversial, and its success is far from assured. Christof Koch of the California Institute of Technology, a scientist who studies consciousness, says the Swiss project provides vital data about how part of the brain works. But he says that Dr. Markram’s approach is still missing algorithms, the biological programming that yields higher-level functions.

“You need to have a theory about how a particular circuit in the brain” can trigger complex, higher-order properties, Dr. Koch argues. “You can’t assemble ever larger data fields and shake it and say, ‘Ah, that’s how consciousness emerges.'”

The possibility of simulating consciousness by building a model of the brain is one of those frustrating quandaries that will seemingly only ever be answered by someone succeeding at doing it; the proof is quite literally in the pudding. Still, Markram is pretty convinced he’s on the right track, going so far as to announce in his TED talk that he’ll have built a model human brain within the next decade… which is something that AI researchers have been saying since the sixties, I believe. I’d love to see it happen, but you’ll forgive me if I don’t hold my breath or place any bets just yet.

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The half-life of data: bug or feature?

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privacyThe great paradox of electronic data must surely be that while the stuff we want to keep is considered frangible and at risk (think of the old programmer’s adage – “if your data doesn’t exist in three separate locations, it might as well not exist at all), the stuff we’d rather have disappear (that inebriated email to your ex-partner or lawyer, or that Facebook picture of you smoking crack on the steps of the town hall) has a tendency of hanging around out in “the cloud” long enough to embarass or incriminate. [image by rpongsaj]

The answer to the first problem is obviously to take multiple geographically-separated back-ups (and make a yearly sacrifice to Cthulhu for peace of mind); the latter is a bit more tricky, but a team at the University of Washington think they may have cracked it with a system named Vanish, which is designed to “give users control over the lifetime of personal data stored on the web or in the cloud. Specifically, all copies of Vanish encrypted data — even archived or cached copies — will become permanently unreadable at a specific time, without any action on the part of the user or any third party or centralized service.”

Sounds intriguing – so how does it work?

We created self-destructing data to try to address this problem. Our prototype system, called Vanish, shares some properties with existing encryption systems like PGP, but there are also some major differences. First, someone using Vanish to “encrypt/encapsulate” information, like an email, never learns the encryption key. Second, there is a pre-specified timeout associated with each encrypted/encapsulated messages. Prior to the timeout, anyone can read the encrypted/encapsulated message. After the timeout, no one can read that message, because the encryption key is lost due to a set of both natural and programmed processes. It is therefore impossible for anyone to decrypt/decapsulate that email after the timer expires.

[…]

… we leverage an unusual storage media in a novel way: namely, global-scale peer-to-peer networks. Vanish creates a secret key to encrypt a user’s data item (such as an email), breaks the key into many pieces and then sprinkles the pieces across the P2P network. As machines constantly join and leave the P2P network, the pieces of the key gradually disappear. By the time the hacker or someone with a subpoena actually tries to obtain access to the message, the pieces of the key will have permanently disappeared.

It’s a clever idea, that’s for certain, and its application to sensitive emails makes a great deal of sense (though I’d want the low-down from Bruce Schneier before deploying it on anything that mattered). As far as Facebook messages are concerned, though, anyone stupid enough to post incriminating material about themselves or others on the biggest social network on the planet can be assumed to lack the gumption to avail themselves of encryption technologies like Vanish. Maybe it’s just because I spend a lot more time on the internet than is really healthy, but I can’t understand how it isn’t more widely acknowledged that the best way to keep something secret is to avoid talking about it in public spaces… [via BoingBoing]

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How to dismantle a nuclear bomb (before it dismantles you)

old Russian nuclear bombNo, it’s not a U2 reference; in the wake of the proposed nuclear reduction initiatives between the US and Russia, those helpful folk at the BBC have an article on how nuclear weapons are decommissioned – only the procedure they witnessed was a simulation. [image by mikelopoulos]

The dismantlement experiment is a joint exercise between the UK and Norway – the first of its kind – and was held a few miles from Oslo.

The five-day exercise has been keenly anticipated internationally as a way of building trust between nuclear weapons states and non-nuclear weapons states.

It is designed to see if one country can verify the disarmament of another country’s nuclear weapon, but without any sensitive information about national security and weapon design being compromised.

This is one of the things that has always baffled me about these sorts of agreements: everyone saying “oh yes, we should be mutually disarming!” but then tacitly acknowledging that “actually, we’d best be keeping the technology secret, because we don’t really trust you not to build more – and if you do we’ll want to have better ones”. So much for building trust, eh?

Still, the descriptions of the procedure are kind of interesting – not so much from a technical standpoint (you don’t get a list of the wrench sizes you’ll need) but as a physical manifestation of nation-state psychology:

From the start inspectors watch, photograph, seal and tag key items. They cover entry and exit points to the disarmament chamber, sweeping all those going in and out to ensure no radioactive material is smuggled away.

“It is a very choreographed process, almost like a ballet,” says Mr Persbo. “Timings are very precise.”

The amount of fissile material in a nuclear bomb is itself classified, so a number of techniques have to be employed by the inspectors to ensure nothing is diverted when they are not able to measure it in detail themselves.

Each country’s scientists have separately designed and built their own prototype devices known as “information barriers”, which can confirm that an agreed amount of radioactive material is present in any container.

If nothing else, you’ve got the switcheroo-loophole plot mechanics for a fissile re-run of The Italian Job right there. That should make for a cheery movie… but if you want some real nuclear angst to set you up for the weekend, you can read this (PDF) report from the International Commission on Nuclear Non-proliferation and Disarmament that looks at the possibility of the old and flaky nuclear command and control infrastructures of the superpowers being hacked by terrorists in order to kick off a modern-day Ragnarok. I can hear Dan Brown firing up his word processor as we speak… [via SlashDot]

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Over to Mars in 39 days

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marsA fascinating article at New Scientist on a new nuclear powered ion drive called VASIMR that could transport astronauts to Mars in as little as 39 days:

VASIMR works something like a steam engine, with the first stage performing a duty analogous to boiling water to create steam. The radio frequency generator heats a gas of argon atoms until electrons “boil” off, creating plasma. This stage was tested for the first time on 2 July at Ad Astra’s headquarters in Webster, Texas
…
Thanks to the radio frequency generator, VASIMR can reach power levels a hundred times as high as other engines, which simply accelerate their plasma by sending it through a series of metal grids with different voltages. In that setup, ions colliding with the grid tend to erode it, limiting the power and lifetime of the rocket. VASIMR’s radio frequency generator gets around that problem by never coming into contact with the ions.

Hitherto most plans to get to Mars involve lengthy journey times, during which exposure to cosmic rays and extended periods of weightlessness (ameliorated somewhat by centrifugal artificial gravity) could have a debilitating effect on the adventurers.

The creation of these powerful ion drives is an exciting and interesting development. Certainly I hope to see someone get to Mars within my lifetime. I wonder what technique will be used?

[from New Scientist][image from chipdatajeffb on flickr]

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More blogs about science and food: The neuroscience of obesity

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baconIn a post entitled “The Neuroscience of McGriddles,” Jonah Lehrer (How We Decide; Proust Was a Neuroscientist) samples the “eerily delicious” McDonald’s product and reaches some dark conclusions:

…The most pleasurable thing about the sandwich isn’t the pancake or the bacon: it’s the calories. According to a recent paper in Neuron, the brain also receives rewarding input from metabolic processes that have nothing to do with the tongue. When you eat at McDonald’s, a big part of the pleasure comes from the fact that the food is sustenance, fuel, energy. Even mediocre food is a little rewarding.

Indeed, even mice with an impaired sense of taste still prefer sugar water over both plain water and water with artificial sweetener. “What they enjoyed were the calories.” And humans’ desire for high-calorie food seems based on our evolutionary investment in a large cranium.

This is a troubling idea, since it reveals the very deep biological roots underlying the obesity epidemic. Let’s imagine, for instance, that some genius invented a reduced calorie bacon product that tasted exactly like bacon, except it had 50 percent fewer calories. It would obviously be a great day for civilization. But this research suggests that such a pseudo-bacon product, even though it tasted identical to real bacon, would actually give us much less pleasure. Why? Because it made us less fat. Because energy is inherently delicious. Because we are programmed to enjoy calories.

[Image: brian cors; thanks to Dinosaur Comics for the link: “Food’s neat, you guys!”]