Archive for the ‘Science & Technology’ Category

Untangling the Search for Social Status from the Search for Truth

November 16, 2008

Euler and Diderot image
Euler on the left and Diderot on the right.

False Stories With True Lessons
It has been pointed out to me that the story about Pythagoras and Hippasus that I wrote about in my previous post was probably not historically accurate. I certainly hope so for Hippasus… Though the events might never have happened, the moral of the story is true, and you should be careful to keep “truth” as your ultimate goal instead of “being right”.

Leonhard Euler vs. Denis Diderot
There is another fictional anecdote that teachers us a similar lesson: The apocryphal encounter between Leonhard Euler and Denis Diderot.

The French philosopher Denis Diderot was visiting Russia on Catherine the Great’s invitation. However, the Empress was alarmed that the philosopher’s arguments for atheism were influencing members of her court, and so Euler was asked to confront the Frenchman. Diderot was later informed that a learned mathematician had produced a proof of the existence of God: he agreed to view the proof as it was presented in court. Euler appeared, advanced toward Diderot, and in a tone of perfect conviction announced, “Sir, (a+b^n)/n = x, hence God exists—reply!”. Diderot, to whom (says the story) all mathematics was gibberish, stood dumbstruck as peals of laughter erupted from the court. Embarrassed, he asked to leave Russia, a request that was graciously granted by the Empress.

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Just be Glad You Aren’t Pythagoras’s Student…

November 15, 2008

Raffaello Sanzio - Pythagoras photo

If anyone who reads this is part of academia and is frustrated by how conservative his chosen field is (”Science advances one funeral at a time”), this story should make you appreciate more the current scientific climate.

From Fermat’s Last Theorem by Simon Singh:

One story claims that a young student by the name of Hippasus was idly toying with the number √2, attempting to find the equivalent fraction. Eventually he came to realize that no such fraction existed, i.e. that √2 is an irrational number. Hippasus must have been overjoyed by his discovery, but his master was not. Pythagoras had defined the universe in terms of rational numbers, and the existence of irrational numbers brought his ideal into question. The consequence of Hippasus’ insight should have been a period of discussion and contemplation during which Pythagoras ought to have come to terms with this new source of numbers. However, Pythagoras was unwilling to accept that he was wrong, but at the same time he was unable to destroy Hippasus’ argument by the power of logic. To his eternal shame he sentenced Hippasus to death by drowning.

The ability to change our minds when presented with evidence that disproves our beliefs - even our most entrenched ones - is a hard habit to acquire, but it is extremely valuable. When you start doubting, don’t turn away. Look into the light until your eyes adjust, and see if there is something there.

As P. C. Hodgell said: “That which can be destroyed by the truth should be.” See the Twelve Virtues of Rationality by Eliezer Yudkowsky.

See also: Untangling the Search for Social Status from the Search for Truth

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Humans are Tone Deaf to Probabilistic Reasoning

October 30, 2008

In his book The Blank Slate, Steven Pinker makes an interesting point about the fact that our brains haven’t evolved to intuitively grasp probabilities. It is an acquired skill like reading, not something innate like walking.

This can lead to scenarios like this:

Some experts are describing the risks of accident at some nuclear waste storage site. They describe various conceivable sequences of events that could lead to failure. For example, accidental drilling in the wrong place, erosion, undetected cracks in the rocks, which could lead to groundwater contamination. Then natural water movement, or volcanic activity, or a large meteorite impact could damage the site and release radioactive materials in the biosphere. The experts will estimate the probability of each event, or each chain of event, and numbers like 1 in X millions will come up.

To the experts, this is reassuring. They are basically saying: “This is pretty damn safe.” But they are speaking a different language from most people.

As Pinker says:

“When people hear these analyses, however, they are not reassured but become more fearful than ever — they hadn’t realized there are so, many ways for something to go wrong! They mentally tabulate the number of disaster scenarios, rather than mentally aggregating the probabilities of the disaster scenarios.”

How to make it better
How can we improve the situation in the hope that more rational decision-taking will take place? The only short-term realistic solution seems to be education. Just like we have no innate cognitive organs for abstract mathematics or reading but still can learn to use our brains to acquire these skills, we should try to make the understanding of probabilistic thinking more widespread.

We don’t expect people who have never studied physics at all to be any good at it, so why do we expect that decision-makers (and the voters/shareholders that supports them) will be able to understand probabilities - especially in complex situations - when they weigh the pros and cons of some proposal.

Automatically Duplicating Keys from Photos

October 29, 2008

Duplicating Keys

This is one of those ideas that once you see you wonder why it hasn’t been done before. Well, it certainly was done often, but probably by expert locksmiths doing it manually… This software could simplify the whole procedure by an order of magnitude, making it accessible to any amateur.

UC San Diego computer scientists have built a software program that can perform key duplication without having the key. Instead, the computer scientists only need a photograph of the key. [...]

In one demonstration of the new software system, the computer scientists took pictures of common residential house keys with a cell phone camera, fed the image into their software which then produced the information needed to create identical copies. In another example, they used a five inch telephoto lens to capture images from the roof of a campus building and duplicate keys sitting on a café table more than 200 feet away. [...]

“If you go onto a photo-sharing site such as Flickr, you will find many photos of people’s keys that can be used to easily make duplicates. While people generally blur out the numbers on their credit cards and driver’s licenses before putting those photos on-line, they don’t realize that they should take the same precautions with their keys” said Savage.

It will take a little while before this technology is used by the common thief, but it’s only a matter of time before the software is freely available online and key-making machines that can take digital input are available, making duplicating keys easier (and safer) than other ways of breaking into houses.

Source: Physorg

Using Patterns in Space Dust to Detect Earth-Like Extrasolar Planets

October 11, 2008

NASA Dust Rings Exoplanets image

Interplanetary Space Dust Fingerprints
NASA’s Goddard Space Flight Center has been running supercomputer simulations of the impact of extrasolar planets on the dust that surrounds stars with orbiting bodies. The results seem to show that we could use patterns in that dust to detect planets smaller than what even advanced telescopes could detect. They mention the possibility of detecting planets as small as Mars (which is about 15% of Earth’s volume and 11% of the mass)!

Working with Marc Kuchner at NASA’s Goddard Space Flight Center in Greenbelt, Md., Stark modeled how 25,000 dust particles responded to the presence of a single planet — ranging from the mass of Mars to five times Earth’s — orbiting a sunlike star. Using NASA’s Thunderhead supercomputer at Goddard, the scientists ran 120 different simulations that varied the size of the dust particles and the planet’s mass and orbital distance.

“Our models use ten times as many particles as previous simulations. This allows us to study the contrast and shapes of ring structures,” Kuchner adds. From this data, the researchers mapped the density, brightness, and heat signature resulting from each set of parameters.

NASA Dust Rings Exoplanets image

You can actually check out the 120 simulation models by yourself in the Exozodi Simulation Catalog.

What This Means for the Future?
It’s less than certain that if humans colonize space, they’ll do it in their current biological form, so we won’t necessarily need Earth-like planets that can be terraformed. But it’s still a good idea to look, if only to have a more accurate map of the universe.

Last April I wrote about the discovery of the First Potentially Habitable Planet Outside the Solar System, but it had a radius 50% bigger than Earth and gravity about twice as strong. Now the race is on to discover smaller and more Earth-like exoplanets.

Source: NASA

See also:

New Study: “Deficiency of vitamin D can impact 36 organs”

October 9, 2008

I’ve been convinced for a while that taking vitamin D supplements is worth it, and study after study seems to confirm my choice.

Here’s what the most recent one from the University of California Riverside has to say:

In a paper published in the August issue of the American Journal of Clinical Nutrition, [Anthony Norman, an international expert on vitamin D,] identifies vitamin D’s potential for contributions to good health in the adaptive and innate immune systems, the secretion and regulation of insulin by the pancreas, the heart and blood pressure regulation, muscle strength and brain activity. In addition, access to adequate amounts of vitamin D is believed to be beneficial towards reducing the risk of cancer.

Norman also lists 36 organ tissues in the body whose cells respond biologically to vitamin D. The list includes bone marrow, breast, colon, intestine, kidney, lung, prostate, retina, skin, stomach and the uterus.

According to Norman, deficiency of vitamin D can impact all 36 organs. Already, vitamin D deficiency is associated with muscle strength decrease, high risk for falls, and increased risk for colorectal, prostate and breast and other major cancers.

The study’s recommendation for all adults is to have an average daily intake of at least 2000 IU. Levels under 10,000 IU/day are considered safe (more about toxicity here).

If you think you’re getting enough vitamin D just from the sun, the only way to know is to get a blood test for 25(OH) levels. A study showed that over half of residents of Miami, Florida, were deficient in vitamin D, and it gets worse as you go Northward. According to Dr. William Davis, a cardiologist who strongly recommends vitamin D supplements, even a tan doesn’t necessarily mean that you’re not vit D deficient, especially if you’re older (the skin loses its ability to generate vitamin D as you age).

Personally, I currently take 4,000 IU per day (in gelcaps like these, not dry tablets, because vitamin D is fat-soluble). If you decide to buy some, make sure to get D3 (cholecalciferol) and not the more expensive but less effective D2 (ergocalciferol).

About cost: 4,000 IU per day of Vitamin D costs me about $25.20 per year. There’s really no reason not to do it. And while you’re at it, also get a good multi-vitamin and some Omega 3 (I take around 1200 EPA + 600 DHA per day).

Update: Vitamin D deficiency might be linked to Parkinson’s disease.

Update: Monthly vitamin D supplement safe and effective.

Source: EurekAlert

SpaceX Update on Falcon 1 Flight 4

October 8, 2008

SpaceX Falcon 1 Launch Pad photo

After a Week Reviewing the Data…
Elon Musk wrote a short post on SpaceX’s website about Falcon 1’s fourth launch, which was successful with a final orbit, confirmed by US Space Command, of 621 km by 643 km.

Orbit was achieved with the first burn terminating at 330.5 km altitude and 8.99 degree inclination. The goal for initial insertion was a 330 km altitude and a 9.0 degree inclination, so this was right on target! Accuracy far exceeded our expectations, particularly given that this was the first time Falcon 1 reached orbit.

According to SpaceX’s video, when the stage 2 engine was cut off, Falcon 1 was moving at a relative velocity of 26,327 kph (16,358 mph). It took it about one and a half hours to circle the Earth!

The next flight of Falcon 1 is tentatively scheduled for March next year and will carry a Malaysian primary satellite, as well as US government secondary satellites, to near equatorial orbit. Flight 6 will probably be a Defense Department satellite in the summer and Flight 7 a commercial satellite mission in the fall. In 2010, I expect the launch cadence for Falcon 1 to step up to a mission every two to three months.

Check out the very cool highlight reel of the Falcon 1 flight.

SpaceX Falcon 1 Flight 4 Launch photo

Source: SpaceX

See also:

Seminar on Global Catastrophic Risks

October 8, 2008

November 14, 2008
Computer History Museum, Mountain View, CA

Organized by: Institute for Ethics and Emerging Technologies, the Center for Responsible Nanotechnology and the Lifeboat Foundation

A day-long seminar on threats to the future of humanity, natural and man-made, and the pro-active steps we can take to reduce these risks and build a more resilient civilization. Seminar participants are strongly encouraged to pre-order and review the Global Catastrophic Risks volume edited by Nick Bostrom and Milan Cirkovic, and contributed to by some of the faculty for this seminar.

This seminar will precede the futurist mega-gathering Convergence 08, November 15-16 at the same venue, which is co-sponsored by the IEET, Humanity Plus (World Transhumanist Association), the Singularity Institute for Artificial Intelligence, the Immortality Institute, the Foresight Institute, the Long Now Foundation, the Methuselah Foundation, the Millenium Project, Reason Foundation and the Accelerating Studies Foundation.

SEMINAR FACULTY

  • Nick Bostrom Ph.D., Director, Future of Humanity Institute, Oxford University
  • Jamais Cascio, research affiliate, Institute for the Future
  • James J. Hughes Ph.D., Exec. Director, Institute for Ethics and Emerging Technologies
  • Mike Treder, Executive Director, Center for Responsible Nanotechnology
  • Eliezer Yudkowsky, Research Associate. Singularity Institute for Artificial Intelligence
  • William Potter Ph.D., Director, James Martin Center for Nonproliferation Studies

Register here

CERN Unveils the Worldwide LHC Computing Grid

October 3, 2008

CERN LHC Grid Computing Data Center photo

15 Petabytes of Data Each Year
When in operation, the Large Hadron Collider (LHC) is expected to produce 15 million gigabytes of data per year. That a lot, to say the least. Enough information to create a 21-kilometre-high stack of CDs annually.

To crunch all that data, CERN will use a grid computing system that has been unveiled today: The Worldwide LHC Computing Grid (WLCG - physicists love acronyms).

CERN LHC Grid Computing Data Center photo

A Few Facts About the Worldwide LHC Computing Grid

  • 100,000 processors (at least) in 32 countries
  • Tier-0 is one site: the CERN Computing Centre. All data passes through this central hub but it provides less than 20% of the total compute capacity.
  • Tier-1 comprises eleven sites, located in Canada, France, Germany, Italy, the Netherlands, the Nordic countries, Spain, Taipei, and the UK, with two sites in the USA.
  • Tier-2 comprises over 140 sites, grouped into 38 federations covering Australia, Belgium, Canada, China, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Italy, India, Israel, Japan, Republic of Korea, the Netherlands, Norway, Pakistan, Poland, Portugal, Romania, Russia, Slovenia, Spain, Sweden, Switzerland, Taipei, Turkey, the U.K, Ukraine, and the U.S. Tier-2 sites will provide around 50% of the capacity needed to process the LHC data.
  • Tier-2 sites then feed their data to PC clusters in physics institutes around the world, such that groups of scientists and individuals can analyze LHC data from their own desks.
  • Access to experimental data needs to be provided for the 5000 scientists in some 500 research institutes and universities worldwide.
  • In order to distribute this data, CERN relies on dedicated 10Gbit/s fiber-optic lines that connect CERN with the 11 Tier-1 data centers on the grid. The Tier-2 centers are connected to the grid via regular Internet connections.
  • All data need to be available over the 15 year estimated lifetime of the LHC

This is only anecdotal, but a photo from CERN shows a computer booting, and on the screen we can see that it has 2 Intel Xeons E5345 Quads at 2.33 Ghz. The amount of RAM is hard to see, but I think it’s 16 gigabytes.

CERN Large Hadron Collider LHC photo

LHC@home
Some work might also be done by volunteers who donate their idle CPU cycles via a distributed computing program called LHC@home (which is one the BOINC platform).

So far LHC@home has been running a simulation of “particles traveling around the LHC to study the stability of their orbits” (more details here), but CERN is looking for ways to use volunteer CPUs for more. Because of the enormous amounts of data that would need to be transfered, LHC@home volunteers won’t be able to do the same kind of crunching that the WLCG sites do, but with a little luck something interesting to do will be found for them (though I still think that crunching for Rosetta@home is the best way to donate your idle CPU cycles).

Sources:

See also:

Elon Musk on SpaceX’s Goal

October 2, 2008

Elon Musk founder of SpaceX photo

Somehow we have to solve these problems and reduce the cost of human spaceflight by a factor of 100. That’s why I started SpaceX. By no means did I think victory was certain. On the contrary, I thought the chances of success were tiny, but that the goal was important enough to try anyway.

We’re making progress. If we succeed in recovery and reflight of our Falcon 9 rocket, which carries 11 tons of payload into orbit, it will be the first fully reusable orbital rocket and one of the most significant developments since the dawn of rocketry. At $35 million to manufacture, it’s already four times cheaper than comparable single-use vehicles from Boeing or Lockheed. However, since Falcon 9 costs only $200,000 to refuel (and reoxidize), an efficient refurbishment and launch operation would allow the production costs to be amortized over many flights. This has the potential to bring the per-launch price down to about $1 million, a hundredfold improvement over current costs. And if that happens, life will become sustainably multiplanetary in less than a century.

Update: There’s another interest piece about Elon Musk at the Mercury News.

Source: Esquire

See also: SpaceX Falcon 1 Rocket Reaches Orbit on 4th Try

SpaceX Falcon 1 Rocket Reaches Orbit on 4th Try

September 30, 2008

SpaceX Falcon 1 Rocket Launch photo

Stars My Destination
After the third try, Elon Musk, the founder of SpaceX, co-founder of Paypal, chairman of SolarCity and chairman of Tesla Motors (beat that resumé!) was interviewed by WIRED about the difficulties of making his space rockets reach orbit:

Wired.com: How do you maintain your optimism?

Musk: Do I sound optimistic?

Wired.com: Yeah, you always do.

Musk: Optimism, pessimism, fuck that; we’re going to make it happen. As God is my bloody witness, I’m hell-bent on making it work.

Falcon 1: The First Privately Developed Rocket to Orbit the Earth
Well kids, perseverance pays off. On the 4th try, the 70-foot Falcon 1 rocket reached orbit wit a 364-pound dummy payload: “The data shows we achieved a super precise orbit insertion — middle of the bullseye — and then went on to coast and restart the second stage, which was icing on the cake.” Check out the video of the highlights of the launch.

“This really means a lot,” Musk told a crowd of whooping employees. “There’s only a handful of countries on Earth that have done this. It’s usually a country thing, not a company thing. We did it.”

Musk pledged to continue getting rockets into orbit, saying the company has resolved design issues that plagued previous attempts.

Last month, SpaceX lost three government satellites and human ashes including the remains of astronaut Gordon Cooper and “Star Trek” actor James Doohan after its third rocket was lost en route to space. The company blamed a timing error for the failure that caused the rocket’s first stage to bump into the second stage after separation.

SpaceX’s maiden launch in 2006 failed because of a fuel line leak. Last year, another rocket reached about 180 miles above Earth, but its second stage prematurely shut off.

The Falcon 1, at $7.9 million each, is what you could call the budget model. In fact, $7.9 million is basically pocket changed compared to what government agencies like NASA are used to paying to contractors like Lockheed Martin & co.

SpaceX is also working on the Falcon 9 (12,500 kg to low Earth orbit, and over 4,640 kg to geosynchronous transfer orbit) and Falcon 9 Heavy (28,000 kg to low Earth orbit, and over 12,000 kg to geosynchronous transfer orbit) to help NASA reach the International Space Station, among other things. These should cost between $36.75 million and $104 million each depending on the model and mission, and the first launch is scheduled for the first quarter of 2009.

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Humans Have Not Evolved to Intuitively Understand Complexity

September 19, 2008

Often while looking at random flora and fauna (including humans), I marvel at evolution’s work. To think that all these intricate living systems have evolved without conscious design. The more I learn about biology, the more amazing it seems!

But then, I have to remember that I am an evolved creature myself, and my species has not evolved to be able to easily grasp the levels of complexity involved with the evolution of biological lifeforms (long time scales, interactions of complex systems, etc).

The primeval savanna where selection pressure formed my brain had no need for this; it’s just a lucky side-effect that I’m now able to think about it at all, and in the grand scheme of things, my understanding is superficial and forced. I can’t simply hold all the elements in my head and run simulations in the way that I can effortlessly know where a falling baseball is going to hit the ground. To my limited mind, on some level, it all seems almost impossibly complex, even if I know more abstractly how it happened. It’s like trying to visualize large numbers. You know what a trillion is in the abstract, but you don’t really grasp it.

But that fact says as much about me, about us, as about the phenomenon itself. A higher intelligence (an AI that could hold a whole planet’s worth of quarks in its mind, for example) might not find life (or other complex phenomena) so special. Its reaction might be more like “duh”.

Cognitive Bias: Kids Likely to Misperceived Own Weight if Surrounded by Obese Friends & Family

September 17, 2008

Montreal, September 17, 2008 – Kids and teens surrounded by overweight peers or parents are more likely to be oblivious to their own extra pounds than kids from thin entourages, according to a new study by researchers from the Université de Montréal, McGill University, Concordia University and the Ste. Justine Hospital Research Centre.

“When children’s parents and schoolmates are overweight or obese, their own overweight status may seem normal by comparison. The higher the BMI of their friends and family, the more kids are likely to underestimate their weight – a trend consistent for both sexes, regardless of the socioeconomic levels of their school or family,” said lead author Katerina Maximova, a PhD student in the Department of Epidemiology, Biostatistics, and Occupational Health at McGill University.

This seems to make intuitive sense, though I wonder how much it also applies to other things. Physical attractiveness? Intelligence? Language skills? Physical dexterity? Empathy and altruism? Perseverance? Honesty?

It is no secret that we are influenced by our peers, but how much of it is because of what we are taught, and how much of it is simply because we use the people who surround us as a measuring stick to compare ourselves to? This kind of calibration seems obvious, and I’d really be surprised if there wasn’t a significant correlation between our traits and those of people around us, but I’d love to see real studies on it. It would be especially useful to find out what types of factors can make people not resemble their peers and hold themselves to different standards.

Source: EurekAlert

See also: Rationality

Nanotube-Based Chemical Sensors to Defend Against Chemical Attacks

September 16, 2008

Chemical Sensor based on Nanotubes photo

I’ve written a fair bit about detection mechanisms (see links at the end of this post) because, as the old saying goes, an ounce of prevention is worth a pound of cure. Making our society more robust is the best way to reliably improve outcomes.

Nanotube-Based Chemical Sensors
Nanotubes strike again (what can’t we do with them?):

What is needed is a cheap way of detecting such gases and, having raised the alarm, of identifying which gas is involved so that anyone who has inhaled it can be treated. And that is what a team of chemical engineers at the Massachusetts Institute of Technology, led by Michael Strano, think they have created. Not only can their new sensor distinguish between chemical agents, it can detect them at previously unattainable concentrations—as low as 25 parts in a trillion.

The core of Dr Strano’s invention, which he recently described in the journal Angewandte Chemie, is an array of treated carbon nanotubes [and a micro gas chromatograph].

Gases are identified by the way they change the electrical signature of the nanotubes, and because of the way they are made, gas molecules don’t ’stick’ very long to the nanotubes (less than a minute) and so the sensor has a long useful life.

Part of a Technological Immune System
At first, these sensors will probably be used in relatively enclosed public places, where gas attacks are more probably, and to track the movements of pollutants. But as the cost of these sensors go down, they could be integrated into a large distributed “technological immune system” (I previously wrote about putting radiation sensors in cellphones).

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One Step Closer to Space-Based Solar Power

September 15, 2008

Wireless Power Transmission Over a Long Distance
If space-based solar power is ever to be feasible, wireless transmission of power needs to be achieved. We are one step closer to that goal because of a successful experiment that recently took place.

A solid-state phased array transmitter located on the U.S. island of Maui (on Haleakala) and receivers located on the island of Hawai’i (Mauna Loa) and airborne.

The demonstration, achieved by Managed Energy Technologies LLC of the U.S. and sponsored by Discovery Communications, Inc., involved the transmission of RF energy over a distance of up to 148 kilometers (about 90 miles): almost 100-times further than a major 1970s power transmission performed by NASA in the Mojave Desert in California.

The 2008 project (which lasted only 5 months and cost less than $1M) proved that real progress toward Space Solar Power can be made quickly, affordably and internationally, including key participants from the U.S. and Japan.

A number of key technologies were integrated and tested together for the first time in this project, including solar power modules, solid-state FET amplifiers, and a novel “retrodirective” phase control system. In addition, the project developed the first ever “field-deployable” system-developing new information regarding the prospective economics of space solar power / wireless power transmission systems.

There is little doubt in my mind that with sufficiently advanced technology, space-based solar power is the most elegant way to produce lots of always-on clean power relatively cheaply. We might need more advanced nanotechnology before getting there (to create a space elevator to bring down the $/KG of getting materials into orbit), but it’s nothing that can’t be done in theory. Who knows how long it will take to happen, though. Large scale Enhanced Geothermal Systems could happen first, but the oil industry will probably get first dibs on drilling equipment and engineers for a good while longer and it’s not as sexy as a new “Moonshot” to politicians, so funding could be a problem.

Source:

See also:

MIT Study: Human Memory Capacity Much Bigger Than Previously Thought

September 13, 2008

Human Brain photo

a new study from MIT cognitive neuroscientists [has] shown that given the right setting, the human brain can record an amazing amount of information.

In the study, the results of which could have implications for artificial intelligence and for understanding memory disorders, people viewed thousands of objects over five hours. Remarkably, afterward they were able to remember each object in great detail. [...]

The new results suggest that visual capacity is several orders of magnitude higher than the older study implied. “If you encode a lot of detail for each object, you need a lot more space,” Alvarez said.

Earlier studies had shown that people could remember a lot, but it was assumed that we did it by remembering abstract descriptions without too much details. In this study, people not only remembered thousands of images (success rate of around 90% after seeing each image for 3 seconds), but also many details about them (a kitchen cabinet with the door ajar, a glass of water 2/3 full, etc) and could pick the one they had seen before when also shown a slightly altered version.

According to the researchers, two things helped people perform better: Telling them to actively try to remember details, and showing them familiar objects (a remote control, not abstract art).

The former probably just further confirms our intuition that we remember better when we make a conscious effort, and the latter probably means that we don’t make a completely new memory when we can reuse the invariable parts of already existing concepts. In other words, it seems like memory is modular, making it easier to put a pointer to an existing module for “chair” with extra information for “what type of chair”, “what color”, “seen from what angle”, etc, than to create a whole new memory from scratch (for an abstract painting).

It’s the same reason why it’s much easier to remember what someone said in a language that you understand than in a language that you don’t. In one instance, you just create modules pointing to already existing modules for words and concepts. This is further simplified because we have evolved brain-hardware to make processing language easier (the equivalent of a DSP chip in electronics?). In the case of a foreign language, you’d have to create many more modules to try to remember phonetically all the sounds you heard in the right order, a task for which we don’t seem to have dedicated brain-hardware.

I’m just speculating based on my limited knowledge of cognitive science. I’m sure a lot more is known about the above, and I’m looking forward to reading about it in the neuroscience books in my “to read” pile.

These results establish a new bound on the size of human memory, and give credence to artificial intelligence approaches that depend primarily on a large memory capacity.

This certainly has big implications for those who try to create AI by modeling the human brain. Probably not as much for those who are attempting to design AI from scratch because they have a much larger possible design-space.

Source: MIT News

Google Chrome

September 3, 2008

Google Chrome Browser Comic Book image

Google has launched a free and open source web browser, Google Chrome. I haven’t had a chance to try it yet (Mac version should be coming soon), but if it works as advertised, it should be pretty good. It has many interesting features that I hope other browsers will copy quickly.

But what I found most interesting about the launch is the 39-page comic book that was released simultaneously. The words are by the Google engineers that worked on Chrome, and the images are by Scott McCloud. It does a very good job of explaining the browser’s features and architecture to both a technical and non-technical public (though they’re obviously targeting early adopters and not grandmas).

This might actually be one of Google Chrome’s biggest innovations.

The comic book will no doubt be read by more people than standard product documentation, and those who read it have a lot more chances of understanding why Chrome’s new features are worth checking out (who else is getting non-programmers to read about the fine points of HTML rendering engines and memory allocation?). By grabbing more early adopters, Google will probably generate more buzz and increase adoption rate. Even the non-tech traditional media will probably have more accurate stories about the browser, with better narratives and less PR-speak. Very smart. It’s a bit like Apple’s product demos, except that you don’t even need to ask the media to gather in a big room. And more intangibly, it really helps the branding of this product by creating a good first impression.

Big Cruncher Redux

August 29, 2008

Rosetta@home top computers image

For some people, distributed computing is a competitive sport. To them, the credits they receive for work done are the main motivator, and some will even pick which project to contribute to just by looking at how much credits are given out compared to other projects.

Personally, I’m into it because of the scientific potential, and I pick projects based on how much good I think they can do. I only monitor credits to make sure that all my computers are crunching properly. Still, a few months ago I was pleased to discover that my Mac Pro was the 4th fastest computer on the Rosetta@home project.

Because I recently overclocked that Mac Pro using a tool from ZDnet Germany, I checked the “top computers” page again and found that it was now #2 despite a more competitive field, and fairly close to #1, but still not catching up to it.

It took me a few days to realize that the #1 computer was actually a 16-core machine (with 64 gigs of RAM!), while my Mac Pro only has 8 cores. No wonder it was hard to catch up to!

Idle CPUs are sad little unproductive things, wasting their potential. Give yours something interesting to work on.

See also: Graphics Processing Units (GPUs): The Future of Scientific Distributed Computing

Update: Guess I should have waited a bit before posting this. I now officially have the single-computer doing the most work for Rosetta@home!

Rosetta@home top computers image