www.overcomingbias.com/2008/05/faster-than-ein.html
That Alien Message
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Imagine a world much like this one, in which, thanks to gene-selection technologies, the average IQ is 140 (on our scale). Potential Einsteins are one-in-a-thousand, not one-in-a-million; and they grow up in a school system suited, if not to them personally, then at least to bright kids. Calculus is routinely taught in sixth grade. Albert Einstein, himself, still lived and still made approximately the same discoveries, but his work no longer seems exceptional. Several modern top-flight physicists have made equivalent breakthroughs, and are still around to talk. (No, this is not the world Brennan lives in.)
One day, the stars in the night sky begin to change. Some grow brighter. Some grow dimmer. Most remain the same. Astronomical telescopes capture it all, moment by moment. The stars that change, change their luminosity one at a time, distinctly so; the luminosity change occurs over the course of a microsecond, but a whole second separates each change. It is clear, from the first instant anyone realizes that more than one star is changing, that the process seems to center around Earth particularly.
The arrival of the light from the events, at many stars scattered around the galaxy, has been precisely timed to Earth in its orbit. Soon, confirmation comes in from high-orbiting telescopes (they have those) that the astronomical miracles do not seem as synchronized from outside Earth. Only Earth's telescopes see one star changing every second (1005 milliseconds, actually). Almost the entire combined brainpower of Earth turns to analysis. It quickly becomes clear that the stars that jump in luminosity, all jump by a factor of exactly 256; those that diminish in luminosity, diminish by a factor of exactly 256. There is no apparent pattern in the stellar coordinates. This leaves, simply, a pattern of BRIGHT-dim-BRIGHT-BRIGHT...
"A binary message!" is everyone's first thought. But in this world there are careful thinkers, of great prestige as well, and they are not so sure. "There are easier ways to send a message," they post to their blogs, "if you can make stars flicker, and if you want to communicate. Something is happening. It appears, prima facie, to focus on Earth in particular.
To call it a 'message' presumes a great deal more about the cause behind it. There might be some kind of evolutionary process among, um, things that can make stars flicker, that ends up sensitive to intelligence somehow... Yeah, there's probably something like 'intelligence' behind it, but try to appreciate how wide a range of possibilities that really implies.
We don't know this is a message, or that it was sent from the same kind of motivations that might move us. I mean, we would just signal using a big flashlight, we wouldn't mess up a whole galaxy." By this time, someone has started to collate the astronomical data and post it to the Internet. Early suggestions that the data might be harmful, have been... not ignored, but not obeyed, either. If anything this powerful wants to hurt you, you're pretty much dead (people reason).
Multiple research groups are looking for patterns in the stellar coordinates - or fractional arrival times of the changes, relative to the center of the Earth - or exact durations of the luminosity shift - or any tiny variance in the magnitude shift - or any other fact that might be known about the stars before they changed. But most people are turning their attention to the pattern of BRIGHTS and dims. It becomes clear almost instantly that the pattern sent is highly redundant. Of the first 16 bits, 12 are BRIGHTS and 4 are dims.
The first 32 bits received align with the second 32 bits received, with only 7 out of 32 bits different, and then the next 32 bits received have only 9 out of 32 bits different from the second (and 4 of them are bits that changed before). From the first 96 bits, then, it becomes clear that this pattern is not an optimal, compressed encoding of anything.
The obvious thought is that the sequence is meant to convey instructions for decoding a compressed message to follow..."But," say the careful thinkers, "anyone who cared about efficiency, with enough power to mess with stars, could maybe have just signaled us with a big flashlight, and sent us a DVD?" There also seems to be structure within the 32-bit groups; some 8-bit subgroups occur with higher frequency than others, and this structure only appears along the natural alignments (32 = 8 + 8 + 8 + 8).
After the first five hours at one bit per second, an additional redundancy becomes clear: The message has started approximately repeating itself at the 16,385th bit. Breaking up the message into groups of 32, there are 7 bits of difference between the 1st group and the 2nd group, and 6 bits of difference between the 1st group and the 513th group. "A 2D picture!" everyone thinks. "And the four 8-bit groups are colors; they're tetrachromats!"
But it soon becomes clear that there is a horizontal/vertical asymmetry: Fewer bits change, on average, between (N, N+1) versus (N, N+512). Which you wouldn't expect if the message was a 2D picture projected onto a symmetrical grid. Then you would expect the average bitwise distance between two 32-bit groups to go as the 2-norm of the grid separation: √(h2 + v2).
There also forms a general consensus that a certain binary encoding from 8-groups onto integers between -64 and 191 - not the binary encoding that seems obvious to us, but still highly regular - minimizes the average distance between neighboring cells.
This continues to be borne out by incoming bits. The statisticians and cryptographers and physicists and computer scientists go to work. There is structure here; it needs only to be unraveled. The masters of causality search for conditional independence, screening-off and Markov neighborhoods, among bits and groups of bits.
The so-called "color" appears to play a role in neighborhoods and screening, so it's not just the equivalent of surface reflectivity. People search for simple equations, simple cellular automata, simple decision trees, that can predict or compress the message. Physicists invent entire new theories of physics that might describe universes projected onto the grid - for it seems quite plausible that a message such as this is being sent from beyond the Matrix.
After receiving 32 * 512 * 256 = 4,194,304 bits, around one and a half months, the stars stop flickering. Theoretical work continues. Physicists and cryptographers roll up their sleeves and seriously go to work. They have cracked problems with far less data than this. Physicists have tested entire theory-edifices with small differences of particle mass; cryptographers have unraveled shorter messages deliberately obscured.
Years pass. Two dominant models have survived, in academia, in the scrutiny of the public eye, and in the scrutiny of those scientists who once did Einstein-like work. There is a theory that the grid is a projection from objects in a 5-dimensional space, with an asymmetry between 3 and 2 of the spatial dimensions.
There is also a theory that the grid is meant to encode a cellular automaton - arguably, the grid has several fortunate properties for such. Codes have been devised that give interesting behaviors; but so far, running the corresponding automata on the largest available computers, has failed to produce any decodable result. The run continues.
Every now and then, someone takes a group of especially brilliant young students who've never looked at the detailed binary sequence. These students are then shown only the first 32 rows (of 512 columns each), to see if they can form new models, and how well those new models do at predicting the next 224. Both the 3+2 dimensional model, and the cellular-automaton model, have been well duplicated by such students; they have yet to do better. There are complex models finely fit to the whole sequence - but those, everyone knows, are probably worthless.
Ten years later, the stars begin flickering again. Within the reception of the first 128 bits, it becomes clear that the Second Grid can fit to small motions in the inferred 3+2 dimensional space, but does not look anything like the successor state of any of the dominant cellular automaton theories. Much rejoicing follows, and the physicists go to work on inducing what kind of dynamical physics might govern the objects seen in the 3+2 dimensional space.
Much work along these lines has already been done, just by speculating on what type of balanced forces might give rise to the objects in the First Grid, if those objects were static - but now it seems not all the objects are static. As most physicists guessed - statically balanced theories seemed contrived. Many neat equations are formulated to describe the dynamical objects in the 3+2 dimensional space being projected onto the First and Second Grids.
Some equations are more elegant than others; some are more precisely predictive (in retrospect, alas) of the Second Grid. One group of brilliant physicists, who carefully isolated themselves and looked only at the first 32 rows of the Second Grid, produces equations that seem elegant to them - and the equations also do well on predicting the next 224 rows. This becomes the dominant guess. But these equations are underspecified; they don't seem to be enough to make a universe.
A small cottage industry arises in trying to guess what kind of laws might complete the ones thus guessed. When the Third Grid arrives, ten years after the Second Grid, it provides information about second derivatives, forcing a major modification of the "incomplete but good" theory. But the theory doesn't do too badly out of it, all things considered. The Fourth Grid doesn't add much to the picture. Third derivatives don't seem important to the 3+2 physics inferred from the Grids.
The Fifth Grid looks almost exactly like it is expected to look. And the Sixth Grid, and the Seventh Grid. (Oh, and every time someone in this world tries to build a really powerful AI, the computing hardware spontaneously melts. This isn't really important to the story, but I need to postulate this in order to have human people sticking around, in the flesh, for seventy years.)
My moral? That even Einstein did not come within a million light-years of making efficient use of sensory data. Riemann invented his geometries before Einstein had a use for them; the physics of our universe is not that complicated in an absolute sense. A Bayesian superintelligence, hooked up to a webcam, would invent General Relativity as a hypothesis - perhaps not the dominant hypothesis, compared to Newtonian mechanics, but still a hypothesis under direct consideration - by the time it had seen the third frame of a falling apple.
It might guess it from the first frame, if it saw the statics of a bent blade of grass. We would think of it. Our civilization, that is, given ten years to analyze each frame. Certainly if the average IQ was 140 and Einsteins were common, we would. Even if we were human-level intelligences in a different sort of physics - minds who had never seen a 3D space projected onto a 2D grid - we would still think of the 3D->2D hypothesis.
Our mathematicians would still have invented vector spaces, and projections. Even if we'd never seen an accelerating billiard ball, our mathematicians would have invented calculus (e.g. for optimization problems). Heck, think of some of the crazy math that's been invented here on our Earth. I occasionally run into people who say something like, "There's a theoretical limit on how much you can deduce about the outside world, given a finite amount of sensory data."
Yes. There is. The theoretical limit is that every time you see 1 additional bit, it cannot be expected to eliminate more than half of the remaining hypotheses (half the remaining probability mass, rather). And that a redundant message, cannot convey more information than the compressed version of itself. Nor can a bit convey any information about a quantity, with which it has correlation exactly zero, across the probable worlds you imagine.
But nothing I've depicted this human civilization doing, even begins to approach the theoretical limits set by the formalism of Solomonoff induction. It doesn't approach the picture you could get if you could search through every single computable hypothesis, weighted by their simplicity, and do Bayesian updates on all of them.
To see the theoretical limit on extractable information, imagine that you have infinite computing power, and you simulate all possible universes with simple physics, looking for universes that contain Earths embedded in them - perhaps inside a simulation - where some process makes the stars flicker in the order observed.
Any bit in the message - or any order of selection of stars, for that matter - that contains the tiniest correlation (across all possible computable universes, weighted by simplicity) to any element of the environment, gives you information about the environment. Solomonoff induction, taken literally, would create countably infinitely many sentient beings, trapped inside the computations. All possible computable sentient beings, in fact. Which scarcely seems ethical. So let us be glad this is only a formalism.
But my point is that the "theoretical limit on how much information you can extract from sensory data" is far above what I have depicted as the triumph of a civilization of physicists and cryptographers. It certainly is not anything like a human looking at an apple falling down, and thinking, "Dur, I wonder why that happened?"
People seem to make a leap from "This is 'bounded'" to "The bound must be a reasonable-looking quantity on the scale I'm used to." The power output of a supernova is 'bounded', but I wouldn't advise trying to shield yourself from one with a flame-retardant Nomex jumpsuit.
No one - not even a Bayesian superintelligence - will ever come remotely close to making efficient use of their sensory information......is what I would like to say, but I don't trust my ability to set limits on the abilities of Bayesian superintelligences. (Though I'd bet money on it, if there were some way to judge the bet. Just not at very extreme odds.) The story continues: Millennia later, frame after frame, it has become clear that some of the objects in the depiction are extending tentacles to move around other objects, and carefully configuring other tentacles to make particular signs.
They're trying to teach us to say "rock". It seems the senders of the message have vastly underestimated our intelligence. From which we might guess that the aliens themselves are not all that bright. And these awkward children can shift the luminosity of our stars? That much power and that much stupidity seems like a dangerous combination.
Our evolutionary psychologists begin extrapolating possible courses of evolution that could produce such aliens. A strong case is made for them having evolved asexually, with occasional exchanges of genetic material and brain content; this seems like the most plausible route whereby creatures that stupid could still manage to build a technological civilization. Their Einsteins may be our undergrads, but they could still collect enough scientific data to get the job done eventually, in tens of their millennia perhaps.
The inferred physics of the 3+2 universe is not fully known, at this point; but it seems sure to allow for computers far more powerful than our quantum ones. We are reasonably certain that our own universe is running as a simulation on such a computer. Humanity decides not to probe for bugs in the simulation; we wouldn't want to shut ourselves down accidentally.
Our evolutionary psychologists begin to guess at the aliens' psychology, and plan out how we could persuade them to let us out of the box. It's not difficult in an absolute sense - they aren't very bright - but we've got to be very careful...We've got to pretend to be stupid, too; we don't want them to catch on to their mistake. It's not until a million years later, though, that they get around to telling us how to signal back. At this point, most of the human species is in cryonic suspension, at liquid helium temperatures, beneath radiation shielding. Every time we try to build an AI, or a nanotechnological device, it melts down.
So humanity waits, and sleeps. Earth is run by a skeleton crew of nine supergeniuses. Clones, known to work well together, under the supervision of certain computer safeguards. An additional hundred million human beings are born into that skeleton crew, and age, and enter cryonic suspension, before they get a chance to slowly begin to implement plans made eons ago...
From the aliens' perspective, it took us thirty of their minute-equivalents to oh-so-innocently learn about their psychology, oh-so-carefully persuade them to give us Internet access, followed by five minutes to innocently discover their network protocols, then some trivial cracking whose only difficulty was an innocent-looking disguise.
We read a tiny handful of physics papers (bit by slow bit) from their equivalent of arXiv, learning far more from their experiments than they had. (Earth's skeleton team spawned an extra twenty Einsteins, that generation.) Then we cracked their equivalent of the protein folding problem over a century or so, and did some simulated engineering in their simulated physics. We sent messages (steganographically encoded until our cracked servers decoded it) to labs that did their equivalent of DNA sequencing and protein synthesis.
We found some unsuspecting schmuck, and gave it a plausible story and the equivalent of a million dollars of cracked computational monopoly money, and told it to mix together some vials it got in the mail. Protein-equivalents that self-assembled into the first-stage nanomachines, that built the second-stage nanomachines, that built the third-stage nanomachines... and then we could finally begin to do things at a reasonable speed.
Three of their days, all told, since they began speaking to us. Half a billion years, for us. They never suspected a thing. They weren't very smart, you see, even before taking into account their slower rate of time. Their primitive equivalents of rationalists went around saying things like, "There's a bound to how much information you can extract from sensory data." And they never quite realized what it meant, that we were smarter than them, and thought faster.
Posted by Eliezer Yudkowsky at 01:55 AM in Arts, Bayesian, Future, Philosophy, Science
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http://research.ua.edu/archive2007/crayfish.htm
Caving for Creatures
By Chris Bryant - cbryant@ur.ua.edu
Scientists Focus On Blind Crayfish
In Search For Cave Ecology Answers
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Born eyeless, these small, white, almost transparent animals spend their lives underground and have diets that, seemingly, are mud-centered. Their very existence appears tenuous. Ok, so you might not score cave crayfish high on a human-based quality-of-life meter, but you’re not apt to beat them in a quantity of days’ contest, either. In fact, some have contended a species of cave crayfish is among the Earth’s longest living organisms, with a possible life span of well over 150 years.
One species of cave crayfish, Orconectes a. australis – a relative of the above ground crustaceans sometimes called crawdads or mudbugs – is the focus of a project University of Alabama researchers hope to expand into a broad-based look into the relationships between caves and the organisms that live within them. A state wildlife grant is providing UA researchers funding to search for these long-antennaed creatures within 10 Alabama caves.
The project involves the capturing, measuring, tagging, releasing and, subsequent re-capturing of hundreds of cave crayfish over a 3-year period. It is designed to reveal more about the crayfish’s population size, individual growth rates and longevity. The search is not an easy one. "Crayfish can go a lot of places we can’t," says Dr. Alex Huryn, a UA freshwater ecologist leading the project. And their homes are places few biologists have explored. "It’s the final frontier," says Dr. Bernard Kuhajda of caves. "It’s the great unknown."
In some ways, caves are the near perfect settings in which to study organisms, says Michael Venarsky, a doctoral student in the University’s biological sciences department.
"They are these nice, little, perfectly replicated laboratory systems all over the world that have similar environmental characteristics. That opens the door for unbelievable comparison studies." In other ways, they’re not so ideal. "Working in surface streams is difficult enough," Venarsky says, "but working in cave streams is exacerbated by space. There are a lot of caves you have to swim through, that you have to pull your equipment through."
Many cave species are imperiled, so non-lethal means must be developed for sampling efforts. Some cave passages are so cramped explorers must crawl along the caves’ floors, while others require rappelling into 60-foot sink holes. "It’s facing these challenges and difficulties that most people have avoided," says the College of Arts and Sciences’ doctoral student.
And there’s that small matter of looking for a 2-4 inch creature in the complete absence of all natural light. On a recent sampling effort in Hering Cave, southeast of Huntsville, the three UA researchers – insulated with wet suits, boots, and gloves, blanketed by coveralls and topped with helmet lights – gave two visitors a glimpse into their field work.
Entering the cave’s mouth while wading through shin-deep, slowly moving waters, the researchers plod down the boulder-littered stream. With helmet lights illuminating the darkness, they plunge deeper into the cave which lies beneath a mountain.
The stream’s mud-covered floor becomes smooth, and the researchers begin scanning the waters for the near invisible. "Ahhh," groans Venarsky as, equipment in hand, he thrashes at a cave fish. It’s gone as quickly as it appeared. "You’d think a blind fish would be easier to catch," he quips, poking fun at his miss.
As the waters rise, nearly 6-feet deep in stretches before receding to knee deep levels again, so too do the researchers’ successes.
Using small nets for scooping and orange plastic buckets for temporary storage, some 22 cave crayfish are located on this day, including 12 of the primary target species and 10 of a significantly larger species with eyes and more closely resembling small lobsters, in color and body types. Sitting on a sandy bank beside the stream deep within the cave’s heart, Venarsky later uses calipers to individually measure the dozens of temporarily captured animals.
He carefully inserts tiny identification tags, which are luminescent, on the crayfish’s bellies, just underneath their clear skins." Venarsky calls out tag numbers and dimensions which Huryn records in a field journal, while Kuhajda continues the search. For crayfish later recaptured, the tags enable the researchers to determine how much an individual has grown over a set time, before it’s again released.
Later, in Huryn’s office, he and Venarsky discuss the project. "What we’re starting to realize," Venarsky says, "is that these populations appear to be much bigger than initially anticipated."
Seven of Alabama’s 89 known species of crayfish are cave dwellers. "This is a real hotspot for crayfish diversity, worldwide," Venarsky said. "These cave crayfish are an important, unique part of that diversity." Six of the cave species are considered imperiled, and the seventh is believed to be extinct. "From a conservation point of view," Kuhajda said, "we always talk a lot about the rain forests – half a world away – and how many species are going extinct. And, we have the same thing happening right here in Alabama."
Caves have much less variation than most environments, so animals that inhabit them are particularly susceptible to change, says Kuhajda, who recently discovered a previously unknown species of cave shrimp. Cave temperatures, for example, fluctuate little regardless of the season. "As we continue to grow as a population, all creatures are going to have a more difficult time finding an acceptable place to live," says Kuhajda. "We’ve got a lot of diversity here, but we’ve got a lot to lose.
I realize that growth has to occur, but we can do it in an intelligent way." While a frequently referenced, but never formally published, study from the 1970s indicates some cave crayfish were living more than 150 years in its dark habitats, Huryn says he’s skeptical of those conclusions. "When I found that out I was pretty amazed," he says. "One of the things I wanted to do was to get in there and use my own modeling methods to see if I could verify that." Kuhajda offers an easy-to-understand fictitious example to illustrate how growth rates can provide insight into longevity. "If they are 8-inches long, and they grow two inches in three years, they are not a hundred-year-old crayfish.
If they get to six inches long, and they grow a sixteenth of an inch in two or three years, they are very old crayfish." The scientists must also account for the molting of skin the crayfish regularly undergoes and for the possibility that crayfish growth rates are not necessarily constant throughout their lives. Venarsky says he is also intrigued by crayfish diets, which, based on stomach contents, are known to contain sediment. "We don’t know what they are eating and, more importantly, we don’t know the proportion of their diets.
So, how much is coming from sediments, and how much is coming from other animal matter? That’s one of the questions I hope to explore for my dissertation." It’s an exploration that’s taking the UA scientists deep underneath Alabama’s soils. Eventually, it will take them beyond these fascinating animals. "We are using this as a portal to burst into bigger questions about cave ecology," Huryn says. "We’re focusing on crayfish. We think it’s an important element in the food webs, but we’re interested in taking this beyond the crayfish. We want to look at the whole cave food webs and look at energy sources in the different groups of caves."
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www.nasa.gov/mission_pages/ibex/IBEXDidYouKnow_prt.htm
Did You Know...
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What Defines the Boundary of the Solar System?
What do we mean when we say something has an edge, or a boundary? Some things, like a table or a soccer field have clear edges and boundaries. Other objects, like cities and towns, have boundaries that aren’t as easy to see. It is hard to say where they end and something else begins. The solar system is more like a city than a table or soccer field.
You could say that the solar system extends as far as the influence of the Sun. That could mean the influence of the Sun’s light, or the influence of the Sun’s gravity, or the influence of the Sun's magnetic field and solar wind. Could the reach of the Sun’s light be a good way to decide how far the solar system extends? The light from the Sun gets fainter as you move farther away, but there is no boundary where the light stops or where it suddenly gets weaker. How about gravity? Just like light, the influence of the Sun’s gravity extends without limit, although it gets weaker farther away from the Sun.
There is not a boundary at which it stops. Astronomers are still discovering objects in the outer solar system beyond Pluto. The solar wind is different from light or gravity. As it streams away from the Sun it races out toward the space between the stars. We think of this space as "empty" but it contains traces of gas and dust. The solar wind blows against this material and clears out a bubble-like region in this gas.
This bubble that surrounds the Sun and the solar system is called the heliosphere. This is not a bubble like a soap bubble, but more like a cloud of foggy breath that you breathe into chilly winter air. Scientists believe that the closest parts of the heliosphere are 90 times farther away than the distance between the Earth and Sun. That’s three times as far as Pluto. The heliosphere defines one type of boundary of the solar system.
What Happens When the Solar Wind and the Interstellar Medium Collide?
Even though the interstellar medium has a low density, it still has a pressure (similar to air pressure). The solar wind also has a pressure. Close to the Sun, the solar wind has a large pressure and can easily push the interstellar medium away from the Sun. Further away from the Sun, the pressure from the interstellar medium is strong enough to slow down and eventually stop the flow of solar wind from traveling into its surroundings.
The entire area or bubble inside the boundary of the solar system is called the heliosphere. The place where the solar wind slows down and begins to interact with the interstellar medium is called the heliosheath. The heliosheath has a few parts: the termination shock (the innermost part of the boundary), the heliopause (the outermost part of the boundary) and the part in between the inner and outer boundary. Since the Sun is moving relative to the interstellar medium around it, the heliosphere forms a wave or shock in the interstellar medium like a boat in the ocean. This is called the bow shock or wave.
What is the Interstellar Medium?
Outer space is not empty space. The interstellar medium (ISM) is the name for the stuff that is in space between stars in our Milky Way Galaxy. The ISM is mostly made of clouds of hydrogen and helium. The rest of the ISM mostly consists of heavier elements like carbon. About one percent of the ISM is in the form of dust. In some places in space the ISM is not dense at all, but it is much more dense in other regions. However, even the densest parts of the ISM are 1014 (100,000,000,000,000 or 100 trillion) times less dense than the Earth's atmosphere.
The density of the ISM ranges from 0.003 molecules per cubic centimeter in regions of hot ionized gases, or plasma, to more than 100,000 molecules per cubic centimeter in regions where stars form. On average, there are only 1,000 grains of dust in each cubic kilometer of space! Stars form in regions of the ISM that are dense enough for gravity to pull the gas and dust together to make compact, hot spheres.
These protostars eventually become so dense and hot that nuclear fusion begins, and they become stars. Although they are not alive, stars have life-cycles. They are born from the ISM, grow, and die. Some stars die in an explosion called a supernova. After it explodes, a supernova's material is recycled into the ISM. Exploding stars continually replenish the ISM with their material. In turn, gravity pulls the ISM material together to form more stars.
What is the Bow Shock or Bow Wave?
A bow shock or wave will form in front of the heliosphere, as the Sun moves through the interstellar medium. A bow wave is similar to what happens at the prow of a boat, while a bow shock is similar to the shockwave that forms in front of a supersonic jet. If the Sun is moving faster than the speed of sound in the interstellar medium, a bow shock will form. Otherwise, if the Sun is not traveling that fast a bow wave will form.
What is the Heliopause?
The heliopause is the boundary between the Sun's solar wind and the interstellar medium. The solar wind blows a "bubble" known as the heliosphere into the interstellar medium. The outer border of this "bubble" is where the solar wind's strength is no longer great enough to push back the interstellar medium. This is known as the heliopause, and is often considered to be the outer border of the solar system. The zone between the termination shock and the heliopause is known as the heliosheath.
What is the Termination Shock?
The termination shock is the boundary marking one of the outer limits of the Sun's influence, and is one boundary of the solar system. It is where the bubble of solar wind particles slows down so that the particles are traveling slower than the speed of sound. The solar wind particles slow down when they begin to press into the interstellar medium.
The solar wind is made of plasma, and when it slows in this way, it goes through many changes. The solar wind plasma gets smooshed together, or compressed like people crowded together in a tiny room. When it is compressed, it also becomes much hotter, in the same way as a bicycle pump heats up in your hand when you vigorously inflate a tire.
Also, the solar wind carries outward some of the Sun's magnetic field, which now gets stronger at the termination shock and twists around. We have only two direct measurements of the distance to the Termination Shock. These measurements were made by Voyager 1 and Voyager 2. Voyager 1 crossed the termination shock at 94 astronomical units (AU) and Voyager 2 crossed at 84 AU. Even though the Interstellar Medium has a low density, it still has a pressure (think of air pressure.)
The solar wind flow also represents a strong outward pressure. Close to the Sun, the solar wind has a high pressure and can easily push the interstellar medium away from the Sun. Further away from the Sun, the pressure from the Interstellar Medium is strong enough to slow down and eventually stop the flow solar wind from traveling into space.
The place where the speed of the solar wind becomes slower than the speed of sound is called the termination shock. A similar shock is formed when you run water from a faucet into a sink. When the stream of water hits the sink basin, the flowing water spreads out at a relatively fast speed, forming a disk of shallow water that quickly moves outward, like the solar wind inside the termination shock.
Around the edge of the disk, a shock front or wall of water forms; outside the shock front, the water moves relatively slower, like outside the termination shock. Remember, the water shock is only 2-dimensional or flat. The Boundary of our solar system is 3-dimensional like a sphere.
How Does the Solar System Boundary Affect Me?
This graph depicts the fraction of high energy cosmic rays (greater than 100 MeV) that pass through the boundary of the solar system. 100% of them are present outside of the Bow Shock. There is a small drop off in the number that make it through to the heliopause.
More than 50% are stopped between the heliopause and termination shock, which is at approximately 100 AU. This leaves a fraction less than 25% to permeate to the inner solar system. The solar system boundary may be defined as the region where the solar wind slows down and interacts with the Interstellar Medium. If the solar system did not have a boundary, or if the boundary changed size so that it was inside the orbit of the Earth, then there would be at least 4 times the amount of cosmic rays in the solar system.
Luckily the Earth's magnetosphere protects us from some of the cosmic rays that come from outside our solar system. However, if there were a dramatic increase in the number of cosmic rays entering the solar system, it could change the amount of high energy cosmic rays that would be able to reach Earth's surface. Damage to the Earth's ozone layer could occur and cosmic rays may cause damage and mutation to DNA.
What Are Cosmic Rays?
'Cosmic ray' is the (confusing) name given to any kind of energetic particle that comes from outside the Earth. These particles could be single protons, nuclei of different atoms or electrons. Cosmic rays are neither light nor beams of particles, so maybe they should be renamed energetic cosmic particles. Cosmic rays are often made when a star explodes.
This is called a supernova. Some cosmic rays can be produced by the Sun and some can even come from as far away as other galaxies. These particles are very energetic, but also very small. They rarely directly hit anything as they travel through space, but if they do it can cause nuclear reactions with atoms. These reactions are similar to the activities in particle accelerators. The Sun's heliosphere protects the planets and other objects in the solar system from some of these dangerous particles.
The Earth's magnetosphere and atmosphere protect life on Earth from cosmic rays that make it through the heliosphere. Studying the heliosphere will help us to prepare adequate shielding during future space travel
How Do Cosmic Rays Affect DNA?
Cosmic rays can seriously damage DNA. If DNA damage cannot be repaired by the cell, the cell could die. If the damage is copied into more cells, then a mutation could occur. Exposure to large amounts of cosmic rays could increase the risks for cancer, cataracts and neurological disorders. Long term exposure to cosmic rays, or short intense bursts, could affect the evolution of life on Earth.
What Are Energetic Neutral Atoms?
Energetic Neutral Atoms (ENAs) are particles with no charge that move relatively fast. ENAs are formed from particles that are ionized, meaning they have lost electrons. Sometimes, these ions interact with neutral atoms taking the electrons from those neutral atoms and becoming neutral themselves.
Since the particle is no longer charged (it has equal numbers of protons and electrons) it no longer reacts to the magnetic fields, and travels in a straight line from the spot where the interaction occurred. This interaction is called charge exchange. Charge exchange can happen between solar wind ions and neutral atoms from the Interstellar Medium.
Some of these ENAs happen to travel in just the right way so that they enter the IBEX spacecraft for collection. There are so many energetic particles that interact with interstellar neutrals, that even though they could travel in any direction, the IBEX sensors are able to pick up between 1 per hour and a few per minute.
Find this article at: www.nasa.gov/mission_pages/ibex/IBEXDidYouKnow.html
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www.nytimes.com/2005/09/30/opinion/30greene.html?pagewanted=2&_r=2
Joel Holland
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An object's mass is its resistance to being accelerated (to having its speed increased). According to E = mc2, an object's mass depends on its energy. This means that the faster an object goes, the harder one must push to increase its speed. (If an object's "rest mass" - called m0 - is the resistance it has to being sped up from a resting position, then Einstein's result can be written more explicitly as E = m0c2/ (1-v2/c2)½, so m = m0(1-v2/c2)-½, where v2 is the square of the object's speed. As the formula shows, when the object's speed approaches that of light, its mass grows infinitely large, which explains why, regardless of how hard it is pushed, it won't exceed light speed.)
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www.nytimes.com/2005/09/30/opinion/30greene.html?pagewanted=2&_r=2
Published: September 30, 2005
Correction Appended, Op-Ed Contributor
That Famous Equation and You
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DURING the summer of 1905, while fulfilling his duties in the patent office in Bern, Switzerland, Albert Einstein was fiddling with a tantalizing outcome of the special theory of relativity he'd published in June. His new insight, at once simple and startling, led him to wonder whether "the Lord might be laughing ... and leading me around by the nose." But by September, confident in the result, Einstein wrote a three-page supplement to the June paper, publishing perhaps the most profound afterthought in the history of science.
A hundred years ago this month, the final equation of his short article gave the world E = mc². In the century since, E = mc² has become the most recognized icon of the modern scientific era. Yet for all its symbolic worth, the equation's intimate presence in everyday life goes largely unnoticed. There is nothing you can do, not a move you can make, not a thought you can have, that doesn't tap directly into E = mc².
Einstein's equation is constantly at work, providing an unseen hand that shapes the world into its familiar form. It's an equation that tells of matter, energy and a remarkable bridge between them. Before E = mc², scientists described matter using two distinct attributes: how much the matter weighed (its mass) and how much change the matter could exert on its environment (its energy). A 19th century physicist would say that a baseball resting on the ground has the same mass as a baseball speeding along at 100 miles per hour.
The key difference between the two balls, the physicist would emphasize, is that the fast-moving baseball has more energy: if sent ricocheting through a china shop, for example, it would surely break more dishes than the ball at rest. And once the moving ball has done its damage and stopped, the 19th-century physicist would say that it has exhausted its capacity for exerting change and hence contains no energy.
After E = mc², scientists realized that this reasoning, however sensible it once seemed, was deeply flawed. Mass and energy are not distinct. They are the same basic stuff packaged in forms that make them appear different. Just as solid ice can melt into liquid water, Einstein showed, mass is a frozen form of energy that can be converted into the more familiar energy of motion.
The amount of energy (E) produced by the conversion is given by his formula: multiply the amount of mass converted (m) by the speed of light squared (c²). Since the speed of light is a few hundred million meters per second (fast enough to travel around the earth seven times in a single second), c² , in these familiar units, is a huge number, about 100,000,000,000,000,000. A little bit of mass can thus yield enormous energy. The destruction of Hiroshima and Nagasaki was fueled by converting less than an ounce of matter into energy; the energy consumed by New York City in a month is less than that contained in the newspaper you're holding.
Far from having no energy, the baseball that has come to rest on the china shop's floor contains enough energy to keep an average car running continuously at 65 m.p.h. for about 5,000 years. Before 1905, the common view of energy and matter thus resembled a man carrying around his money in a box of solid gold. After the man spends his last dollar, he thinks he's broke. But then someone alerts him to his miscalculation; a substantial part of his wealth is not what's in the box, but the box itself. Similarly, until Einstein's insight, everyone was aware that matter, by virtue of its motion or position, could possess energy.
What everyone missed is the enormous energetic wealth contained in mass itself. The standard illustrations of Einstein's equation - bombs and power stations - have perpetuated a belief that E = mc² has a special association with nuclear reactions and is thus removed from ordinary activity. This isn't true. When you drive your car, E = mc² is at work.
As the engine burns gasoline to produce energy in the form of motion, it does so by converting some of the gasoline's mass into energy, in accord with Einstein's formula. When you use your MP3 player, E = mc² is at work. As the player drains the battery to produce energy in the form of sound waves, it does so by converting some of the battery's mass into energy, as dictated by Einstein's formula.
As you read this text, E = mc² is at work. The processes in the eye and brain, underlying perception and thought, rely on chemical reactions that interchange mass and energy, once again in accord with Einstein's formula.
The point is that although E=mc² expresses the interchangeability of mass and energy, it doesn't single out any particular reaction for executing the conversion.
The distinguishing feature of nuclear reactions, compared with the chemical reactions involved in burning gasoline or running a battery, is that they generate less waste and thus produce more energy - by a factor of roughly a million. And when it comes to energy, a factor of a million justifiably commands attention. But don't let the spectacle of E=mc² in nuclear reactions inure you to its calmer but thoroughly pervasive incarnations in everyday life.
That's the content of Einstein's discovery. Why is it true? Einstein's derivation of E = mc² was wholly mathematical. I know his derivation, as does just about anyone who has taken a course in modern physics. Nevertheless, I consider my understanding of a result incomplete if I rely solely on the math. Instead, I've found that thorough understanding requires a mental image - an analogy or a story - that may sacrifice some precision but captures the essence of the result. Here's a story for E = mc².
Two equally strong and skilled jousters, riding identical horses and gripping identical (blunt) lances, head toward each other at an identical speed. As they pass, each thrusts his lance across his breastplate toward his opponent, slamming blunt end into blunt end. Because they're equally matched, neither lance pushes farther than the other, and so the referee calls it a draw. This story contains the essence of Einstein's discovery.
Let me explain. Einstein's first relativity paper, the one in June 1905, shattered the idea that time elapses identically for everyone. Instead, Einstein showed that if from your perspective someone is moving, you will see time elapsing slower for him than it does for you. Everything he does - sipping his coffee, turning his head, blinking his eyes - will appear in slow motion. This is hard to grasp because at everyday speeds the slowing is less than one part in a trillion and is thus imperceptibly small.
Even so, using extraordinarily precise atomic clocks, scientists have repeatedly confirmed that it happens just as Einstein predicted. If we lived in a world where things routinely traveled near the speed of light, the slowing of time would be obvious. Let's see what the slowing of time means for the joust. To do so, think about the story not from the perspective of the referee, but instead imagine you are one of the jousters.
From your perspective, it is your opponent - getting ever closer - who is moving. Imagine that he is approaching at nearly the speed of light so the slowing of all his movements - readying his joust, tightening his face - is obvious. When he shoves his lance toward you in slow motion, you naturally think he's no match for your swifter thrust; you expect to win. Yet we already know the outcome.
The referee calls it a draw and no matter how strange relativity is, it can't change a draw into a win. After the match, you naturally wonder how your opponent's slowly thrusted lance hit with the same force as your own. There's only one answer. The force with which something hits depends not only on its speed but also on its mass. That's why you don't fear getting hit by a fast-moving Ping-Pong ball (tiny mass) but you do fear getting hit by a fast-moving Mack truck (big mass). Thus, the only explanation for how the slowly thrust lance hit with the same force as your own is that it's more massive.
This is astonishing. The lances are identically constructed. Yet you conclude that one of them - the one that from your point of view is in motion, being carried toward you by your opponent on his galloping horse - is more massive than the other. That's the essence of Einstein's discovery. Energy of motion contributes to an object's mass. AS with the slowing of time, this is unfamiliar because at everyday speeds the effect is imperceptibly tiny.
But if, from your viewpoint, your opponent were to approach at 99.99999999 percent of the speed of light, his lance would be about 70,000 times more massive than yours. Luckily, his thrusting speed would be 70,000 times slower than yours, and so the resulting force would equal your own.
Once Einstein realized that mass and energy were convertible, getting the exact formula relating them - E = mc² - was a fairly basic exercise, requiring nothing more than high school algebra. His genius was not in the math; it was in his ability to see beyond centuries of misunderstanding and recognize that there was a connection between mass and energy at all.
A little known fact about Einstein's September 1905 paper is that he didn't actually write E = mc²; he wrote the mathematically equivalent (though less euphonious) m = E/c², placing greater emphasis on creating mass from energy (as in the joust) than on creating energy from mass (as in nuclear weapons and power stations).
Over the last couple of decades, this less familiar reading of Einstein's equation has helped physicists explain why everything ever encountered has the mass that it does. Experiments have shown that the subatomic particles making up matter have almost no mass of their own. But because of their motions and interactions inside of atoms, these particles contain substantial energy - and it's this energy that gives matter its heft.
Take away Einstein's equation, and matter loses its mass. You can't get much more pervasive than that. Its singular fame notwithstanding, E = mc² fits into the pattern of work and discovery that Einstein pursued with relentless passion throughout his entire life.
Einstein believed that deep truths about the workings of the universe would always be "as simple as possible, but no simpler." And in his view, simplicity was epitomized by unifying concepts - like matter and energy - previously deemed separate. In 1916, Einstein simplified our understanding even further by combining gravity with space, time, matter and energy in his General Theory of Relativity. For my money, this is the most beautiful scientific synthesis ever achieved.
With these successes, Einstein's belief in unification grew ever stronger. But the sword of his success was double-edged. It allowed him to dream of a single theory encompassing all of nature's laws, but led him to expect that the methods that had worked so well for him in the past would continue to work for him in the future. It wasn't to be.
For the better part of his last 30 years, Einstein pursued the "unified theory," but it stubbornly remained beyond his grasp. As the years passed, he became increasingly isolated; mainstream physics was concerned with prying apart the atom and paid little attention to Einstein's grandiose quest. In a 1942 letter, Einstein described himself as having become a "a lonely old man who is displayed now and then as a curiosity because he doesn't wear socks."
Today, Einstein's quest for unification is no curiosity - it is the driving force for many physicists of my generation. No one knows how close we've gotten. Maybe the unified theory will elude us just as it dodged Einstein last century. Or maybe the new approaches being developed by contemporary physics will finally prevail, giving us the ultimate explanation of the cosmos.
Without a unified theory it's hard to imagine we will ever resolve the deepest of all mysteries - how the universe began- so the stakes are high and the motivation strong. But even if our science proves unable to determine the origin of the universe, recent progress has already established beyond any doubt that a fraction of a second after creation (however that happened), the universe was filled with tremendous energy in the form of wildly moving exotic particles and radiation.
Within a few minutes, this energy employed E = mc² to transform itself into more familiar matter - the simplest atoms - which, in the course of about a billion years, clumped into planets and stars. During the 13 billion years that have followed, stars have used E = mc² to transform their mass back into energy in the form of heat and light; about five billion years ago, our closest star - the sun - began to shine, and the heat and light generated was essential to the formation of life on our planet.
If prevailing theory and observations are correct, the conversion of matter to energy throughout the cosmos, mediated by stars, black holes and various forms of radioactive decay, will continue unabated. In the far, far future, essentially all matter will have returned to energy.
But because of the enormous expansion of space, this energy will be spread so thinly that it will hardly ever convert back to even the lightest particles of matter. Instead, a faint mist of light will fall for eternity through an ever colder and quieter cosmos. The guiding hand of Einstein's E = mc² will have finally come to rest.
Brian Greene, a professor of physics and mathematics at Columbia, is the author of "The Elegant Universe" and "The Fabric of the Cosmos."Correction: Oct. 2, 2005, Sunday:An Op-Ed article on Friday about Einstein included an errant minus sign in an equation. E = m0c²/(1-v²/c²)½.
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www.newyorker.com/arts/critics/books/2007/12/17/071217crbo_books_gladwell
If What I.Q. Tests Measure is Immutable and Innate, What Explains the Flynn Effect—the Steady Rise in Scores Across Generations?
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One Saturday in November of 1984, James Flynn, a social scientist at the University of Otago, in New Zealand, received a large package in the mail. It was from a colleague in Utrecht, and it contained the results of I.Q. tests given to two generations of Dutch eighteen-year-olds. When Flynn looked through the data, he found something puzzling. The Dutch eighteen-year-olds from the nineteen-eighties scored better than those who took the same tests in the nineteen-fifties—and not just slightly better, much better.
Curious, Flynn sent out some letters. He collected intelligence-test results from Europe, from North America, from Asia, and from the developing world, until he had data for almost thirty countries. In every case, the story was pretty much the same. I.Q.s around the world appeared to be rising by 0.3 points per year, or three points per decade, for as far back as the tests had been administered. For some reason, human beings seemed to be getting smarter.
Flynn has been writing about the implications of his findings—now known as the Flynn effect—for almost twenty-five years. His books consist of a series of plainly stated statistical observations, in support of deceptively modest conclusions, and the evidence in support of his original observation is now so overwhelming that the Flynn effect has moved from theory to fact.
What remains uncertain is how to make sense of the Flynn effect. If an American born in the nineteen-thirties has an I.Q. of 100, the Flynn effect says that his children will have I.Q.s of 108, and his grandchildren I.Q.s of close to 120—more than a standard deviation higher.
If we work in the opposite direction, the typical teen-ager of today, with an I.Q. of 100, would have had grandparents with average I.Q.s of 82—seemingly below the threshold necessary to graduate from high school. And, if we go back even farther, the Flynn effect puts the average I.Q.s of the schoolchildren of 1900 at around 70, which is to suggest, bizarrely, that a century ago the United States was populated largely by people who today would be considered mentally retarded.
For almost as long as there have been I.Q. tests, there have been I.Q. fundamentalists. H. H. Goddard, in the early years of the past century, established the idea that intelligence could be measured along a single, linear scale. One of his particular contributions was to coin the word "moron." "The people who are doing the drudgery are, as a rule, in their proper places," he wrote. Goddard was followed by Lewis Terman, in the nineteen-twenties, who rounded up the California children with the highest I.Q.s, and confidently predicted that they would sit at the top of every profession.
In 1969, the psychometrician Arthur Jensen argued that programs like Head Start, which tried to boost the academic performance of minority children, were doomed to failure, because I.Q. was so heavily genetic; and in 1994 Richard Herrnstein and Charles Murray, in "The Bell Curve," notoriously proposed that Americans with the lowest I.Q.s be sequestered in a "high-tech" version of an Indian reservation, "while the rest of America tries to go about its business."
To the I.Q. fundamentalist, two things are beyond dispute: first, that I.Q. tests measure some hard and identifiable trait that predicts the quality of our thinking; and, second, that this trait is stable—that is, it is determined by our genes and largely impervious to environmental influences.
This is what James Watson, the co-discoverer of DNA, meant when he told an English newspaper recently that he was "inherently gloomy" about the prospects for Africa. From the perspective of an I.Q. fundamentalist, the fact that Africans score lower than Europeans on I.Q. tests suggests an ineradicable cognitive disability.
In the controversy that followed, Watson was defended by the journalist William Saletan, in a three-part series for the online magazine Slate. Drawing heavily on the work of J. Philippe Rushton—a psychologist who specializes in comparing the circumference of what he calls the Negroid brain with the length of the Negroid penis—Saletan took the fundamentalist position to its logical conclusion.
To erase the difference between blacks and whites, Saletan wrote, would probably require vigorous interbreeding between the races, or some kind of corrective genetic engineering aimed at upgrading African stock. "Economic and cultural theories have failed to explain most of the pattern," Saletan declared, claiming to have been "soaking [his] head in each side’s computations and arguments." One argument that Saletan never soaked his head in, however, was Flynn’s, because what Flynn discovered in his mailbox upsets the certainties upon which I.Q. fundamentalism rests.
If whatever the thing is that I.Q. tests measure can jump so much in a generation, it can’t be all that immutable and it doesn’t look all that innate. The very fact that average I.Q.s shift over time ought to create a "crisis of confidence," Flynn writes in "What Is Intelligence?" (Cambridge; $22), his latest attempt to puzzle through the implications of his discovery. "How could such huge gains be intelligence gains? Either the children of today were far brighter than their parents or, at least in some circumstances, I.Q. tests were not good measures of intelligence."
The best way to understand why I.Q.s rise, Flynn argues, is to look at one of the most widely used I.Q. tests, the so-called WISC (for Wechsler Intelligence Scale for Children). The WISC is composed of ten subtests, each of which measures a different aspect of I.Q. Flynn points out that scores in some of the categories—those measuring general knowledge, say, or vocabulary or the ability to do basic arithmetic—have risen only modestly over time.
The big gains on the WISC are largely in the category known as "similarities," where you get questions such as "In what way are ‘dogs’ and ‘rabbits’ alike?" Today, we tend to give what, for the purposes of I.Q. tests, is the right answer: dogs and rabbits are both mammals.
A nineteenth-century American would have said that "you use dogs to hunt rabbits." "If the everyday world is your cognitive home, it is not natural to detach abstractions and logic and the hypothetical from their concrete referents," Flynn writes. Our great-grandparents may have been perfectly intelligent.
But they would have done poorly on I.Q. tests because they did not participate in the twentieth century’s great cognitive revolution, in which we learned to sort experience according to a new set of abstract categories. In Flynn’s phrase, we have now had to put on "scientific spectacles," which enable us to make sense of the WISC questions about similarities. To say that Dutch I.Q. scores rose substantially between 1952 and 1982 was another way of saying that the Netherlands in 1982 was, in at least certain respects, much more cognitively demanding than the Netherlands in 1952.
An I.Q., in other words, measures not so much how smart we are as how modern we are. This is a critical distinction.
When the children of Southern Italian immigrants were given I.Q. tests in the early part of the past century, for example, they recorded median scores in the high seventies and low eighties, a full standard deviation below their American and Western European counterparts.
Southern Italians did as poorly on I.Q. tests as Hispanics and blacks did. As you can imagine, there was much concerned talk at the time about the genetic inferiority of Italian stock, of the inadvisability of letting so many second-class immigrants into the United States, and of the squalor that seemed endemic to Italian urban neighborhoods.
Sound familiar? These days, when talk turns to the supposed genetic differences in the intelligence of certain races, Southern Italians have disappeared from the discussion. "Did their genes begin to mutate somewhere in the 1930s?" the psychologists Seymour Sarason and John Doris ask, in their account of the Italian experience. "Or is it possible that somewhere in the 1920s, if not earlier, the sociocultural history of Italo-Americans took a turn from the blacks and the Spanish Americans which permitted their assimilation into the general undifferentiated mass of Americans?"
The psychologist Michael Cole and some colleagues once gave members of the Kpelle tribe, in Liberia, a version of the WISC similarities test: they took a basket of food, tools, containers, and clothing and asked the tribesmen to sort them into appropriate categories. To the frustration of the researchers, the Kpelle chose functional pairings. They put a potato and a knife together because a knife is used to cut a potato. "A wise man could only do such-and-such," they explained. Finally, the researchers asked, "How would a fool do it?" The tribesmen immediately re-sorted the items into the "right" categories.
It can be argued that taxonomical categories are a developmental improvement—that is, that the Kpelle would be more likely to advance, technologically and scientifically, if they started to see the world that way. But to label them less intelligent than Westerners, on the basis of their performance on that test, is merely to state that they have different cognitive preferences and habits.
And if I.Q. varies with habits of mind, which can be adopted or discarded in a generation, what, exactly, is all the fuss about? When I was growing up, my family would sometimes play Twenty Questions on long car trips. My father was one of those people who insist that the standard categories of animal, vegetable, and mineral be supplemented with a fourth category: "abstract." Abstract could mean something like "whatever it was that was going through my mind when we drove past the water tower fifty miles back."
That abstract category sounds absurdly difficult, but it wasn’t: it merely required that we ask a slightly different set of questions and grasp a slightly different set of conventions, and, after two or three rounds of practice, guessing the contents of someone’s mind fifty miles ago becomes as easy as guessing Winston Churchill. (There is one exception.
That was the trip on which my old roommate Tom Connell chose, as an abstraction, "the Unknown Soldier"—which allowed him legitimately and gleefully to answer "I have no idea" to almost every question. There were four of us playing. We gave up after an hour.) Flynn would say that my father was teaching his three sons how to put on scientific spectacles, and that extra practice probably bumped up all of our I.Q.s a few notches.
But let’s be clear about what this means.
There’s a world of difference between an I.Q. advantage that’s genetic and one that depends on extended car time with Graham Gladwell. Flynn is a cautious and careful writer. Unlike many others in the I.Q. debates, he resists grand philosophizing. He comes back again and again to the fact that I.Q. scores are generated by paper-and-pencil tests—and making sense of those scores, he tells us, is a messy and complicated business that requires something closer to the skills of an accountant than to those of a philosopher.
For instance, Flynn shows what happens when we recognize that I.Q. is not a freestanding number but a value attached to a specific time and a specific test. When an I.Q. test is created, he reminds us, it is calibrated or "normed" so that the test-takers in the fiftieth percentile—those exactly at the median—are assigned a score of 100. But since I.Q.s are always rising, the only way to keep that hundred-point benchmark is periodically to make the tests more difficult—to "renorm" them.
The original WISC was normed in the late nineteen-forties. It was then renormed in the early nineteen-seventies, as the WISC-R; renormed a third time in the late eighties, as the WISC III; and renormed again a few years ago, as the WISC IV—with each version just a little harder than its predecessor.
The notion that anyone "has" an I.Q. of a certain number, then, is meaningless unless you know which WISC he took, and when he took it, since there’s a substantial difference between getting a 130 on the WISC IV and getting a 130 on the much easier WISC. This is not a trivial issue. I.Q. tests are used to diagnose people as mentally retarded, with a score of 70 generally taken to be the cutoff.
You can imagine how the Flynn effect plays havoc with that system. In the nineteen-seventies and eighties, most states used the WISC-R to make their mental-retardation diagnoses. But since kids—even kids with disabilities—score a little higher every year, the number of children whose scores fell below 70 declined steadily through the end of the eighties.
Then, in 1991, the WISC III was introduced, and suddenly the percentage of kids labelled retarded went up. The psychologists Tomoe Kanaya, Matthew Scullin, and Stephen Ceci estimated that, if every state had switched to the WISC III right away, the number of Americans labelled mentally retarded should have doubled.
That is an extraordinary number. The diagnosis of mental disability is one of the most stigmatizing of all educational and occupational classifications—and yet, apparently, the chances of being burdened with that label are in no small degree a function of the point, in the life cycle of the WISC, at which a child happens to sit for his evaluation. "
As far as I can determine, no clinical or school psychologists using the WISC over the relevant 25 years noticed that its criterion of mental retardation became more lenient over time," Flynn wrote, in a 2000 paper. "Yet no one drew the obvious moral about psychologists in the field: They simply were not making any systematic assessment of the I.Q. criterion for mental retardation."
Flynn brings a similar precision to the question of whether Asians have a genetic advantage in I.Q., a possibility that has led to great excitement among I.Q. fundamentalists in recent years. Data showing that the Japanese had higher I.Q.s than people of European descent, for example, prompted the British psychometrician and eugenicist Richard Lynn to concoct an elaborate evolutionary explanation involving the Himalayas, really cold weather, premodern hunting practices, brain size, and specialized vowel sounds.
The fact that the I.Q.s of Chinese-Americans also seemed to be elevated has led I.Q. fundamentalists to posit the existence of an international I.Q. pyramid, with Asians at the top, European whites next, and Hispanics and blacks at the bottom. Here was a question tailor-made for James Flynn’s accounting skills.
He looked first at Lynn’s data, and realized that the comparison was skewed. Lynn was comparing American I.Q. estimates based on a representative sample of schoolchildren with Japanese estimates based on an upper-income, heavily urban sample. Recalculated, the Japanese average came in not at 106.6 but at 99.2.
Then Flynn turned his attention to the Chinese-American estimates.
They turned out to be based on a 1975 study in San Francisco’s Chinatown using something called the Lorge-Thorndike Intelligence Test. But the Lorge-Thorndike test was normed in the nineteen-fifties. For children in the nineteen-seventies, it would have been a piece of cake.
When the Chinese-American scores were reassessed using up-to-date intelligence metrics, Flynn found, they came in at 97 verbal and 100 nonverbal. Chinese-Americans had slightly lower I.Q.s than white Americans. The Asian-American success story had suddenly been turned on its head. The numbers now suggested, Flynn said, that they had succeeded not because of their higher I.Q.s. .
Among whites, virtually everyone who joins the ranks of the mbut despite their lower I.Q.s. Asians were overachievers. In a nifty piece of statistical analysis, Flynn then worked out just how great that overachievement wasanagerial, professional, and technical occupations has an I.Q. of 97 or above. Among Chinese-Americans, that threshold is 90.
A Chinese-American with an I.Q. of 90, it would appear, does as much with it as a white American with an I.Q. of 97. There should be no great mystery about Asian achievement. It has to do with hard work and dedication to higher education, and belonging to a culture that stresses professional success. But Flynn makes one more observation.
The children of that first successful wave of Asian-Americans really did have I.Q.s that were higher than everyone else’s—coming in somewhere around 103. Having worked their way into the upper reaches of the occupational scale, and taken note of how much the professions value abstract thinking, Asian-American parents have evidently made sure that their own children wore scientific spectacles.
"Chinese Americans are an ethnic group for whom high achievement preceded high I.Q. rather than the reverse," Flynn concludes, reminding us that in our discussions of the relationship between I.Q. and success we often confuse causes and effects. "It is not easy to view the history of their achievements without emotion," he writes. That is exactly right. To ascribe Asian success to some abstract number is to trivialize it.
Two weeks ago, Flynn came to Manhattan to debate Charles Murray at a forum sponsored by the Manhattan Institute. Their subject was the black-white I.Q. gap in America. During the twenty-five years after the Second World War, that gap closed considerably.
The I.Q.s of white Americans rose, as part of the general worldwide Flynn effect, but the I.Q.s of black Americans rose faster. Then, for about a period of twenty-five years, that trend stalled—and the question was why. Murray showed a series of PowerPoint slides, each representing different statistical formulations of the I.Q. gap.
He appeared to be pessimistic that the racial difference would narrow in the future. "By the nineteen-seventies, you had gotten most of the juice out of the environment that you were going to get," he said. That gap, he seemed to think, reflected some inherent difference between the races. "Starting in the nineteen-seventies, to put it very crudely, you had a higher proportion of black kids being born to really dumb mothers," he said.
When the debate’s moderator, Jane Waldfogel, informed him that the most recent data showed that the race gap had begun to close again, Murray seemed unimpressed, as if the possibility that blacks could ever make further progress was inconceivable. Flynn took a different approach. The black-white gap, he pointed out, differs dramatically by age.
He noted that the tests we have for measuring the cognitive functioning of infants, though admittedly crude, show the races to be almost the same. By age four, the average black I.Q. is 95.4—only four and a half points behind the average white I.Q. Then the real gap emerges: from age four through twenty-four, blacks lose six-tenths of a point a year, until their scores settle at 83.4.
That steady decline, Flynn said, did not resemble the usual pattern of genetic influence. Instead, it was exactly what you would expect, given the disparate cognitive environments that whites and blacks encounter as they grow older. Black children are more likely to be raised in single-parent homes than are white children—and single-parent homes are less cognitively complex than two-parent homes. The average I.Q. of first-grade students in schools that blacks attend is 95, which means that "kids who want to be above average don’t have to aim as high."
There were possibly adverse differences between black teen-age culture and white teen-age culture, and an enormous number of young black men are in jail—which is hardly the kind of environment in which someone would learn to put on scientific spectacles. Flynn then talked about what we’ve learned from studies of adoption and mixed-race children—and that evidence didn’t fit a genetic model, either.
If I.Q. is innate, it shouldn’t make a difference whether it’s a mixed-race child’s mother or father who is black. But it does: children with a white mother and a black father have an eight-point I.Q. advantage over those with a black mother and a white father. And it shouldn’t make much of a difference where a mixed-race child is born.
But, again, it does: the children fathered by black American G.I.s in postwar Germany and brought up by their German mothers have the same I.Q.s as the children of white American G.I.s and German mothers. The difference, in that case, was not the fact of the children’s blackness, as a fundamentalist would say. It was the fact of their Germanness—of their being brought up in a different culture, under different circumstances. "The mind is much more like a muscle than we’ve ever realized," Flynn said. "It needs to get cognitive exercise.
It’s not some piece of clay on which you put an indelible mark." The lesson to be drawn from black and white differences was the same as the lesson from the Netherlands years ago: I.Q. measures not just the quality of a person’s mind but the quality of the world that person lives in.
By Malcolm Gladwell, December 17, 2007
CORRECTION: In his December 17th piece, "None of the Above," Malcolm Gladwell states that Richard Herrnstein and Charles Murray, in their 1994 book "The Bell Curve," proposed that Americans with low I.Q.s be "sequestered in a ‘high-tech’ version of an Indian reservation." In fact, Herrnstein and Murray deplored the prospect of such "custodialism" and recommended that steps be taken to avert it. We regret the error.
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2 Comments:
Anonymous said...
Genius is lonely. Wisdom is lonelier still. The combination is a killer. Of course it's easy to have a deep, satisfying emotional relationship with a dog or a rabbit, but living in a world where you have no peers or intellectual equals is horribly lonely. And working for a chimpanzee can be intensely frustrating. It's the inability to share more than a tiny fraction of who I am with others that's hardest for me. Feeling light years apart from others, because I can't bridge the gap between my consciousness and theirs. Most of the women that I date think I'm an idiot, or just plain crazy-- because they can't even begin to comprehend my thought processes, and there's no way that I can explain them. It's like trying to teach algebra to a sea urchin. But I love puppies and bunny rabbits. There's nothing whatsoever lacking in puppies and bunny rabbits. I just need something more sometimes. That's all. I need to share things that I can't share with puppies and bunny rabbits. Intelligence is only a part of my problem. I'm also vastly wiser than the average person, as a result of a unique constellation of life experiences, combined with a high existential intelligence aptitude. And, in this world, wisdom is much rarer than intelligence. This is the world I live in: http://www.youtube.com/watch?v=3efW4AziWCg
December 26, 2007 8:25 PM
. . . .Joycelyn80 said...
A happy solution to this problem could be to deny the problem! after all life itself is trivial with its 70 yr something span. One might as well look out for gratification rather than being constrained by a false sense of duty, but then gratification has got its own mode of choosing to station itself at ones heart *sigh*
December 26, 2007 8:35 PM
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