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Modeling Acts of God, Part 2 - Earthquakes

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This is #2 in a series. (Click here for #1 on modeling hurricanes)

Earthquake modeling seems to generate a wide range of emotions, vitriol, successes, and failures - so wide as to need a logarithmic scale, a la Richter.

The Parkfield Earthquake Experiment, now running for over 22 years, has been the development test bed and experimental "lab" for US Geological Survey/State of California efforts to develop physical models of earthquakes that will lead to viable predictions. The USGS site contains a wealth of information on the experiment, and good background on the history of earthquake prediction, which is still highly hit or miss. An interesting excerpt from the site neatly illuminates the need for prediction based on an understanding of physical causes as opposed to one based on statistical correlation only:

Early scientific efforts toward earthquake prediction in the U.S. were directed primarily toward the measurement of physical parameters in areas where earthquakes occur, including seismicity, crustal structure, heat flow, geomagnetism, electrical potential and conductivity, gas chemistry. Central to these efforts was the concept that a precursor might be observed in one or more of these measurements. However, the connection between a commonly accepted precursor and the earthquake was often speculative and uncertain. A coherent physical model was lacking. A model on which a scientific prediction could be based began to be developed in the late 1970's and early 1980's, and is described in three seminal papers. Allan Lindh of the USGS, proposed a multi-year, integrated observation program at Parkfield, combining seismic, geodetic, creep, strain, tilt and magnetic measurements with theoretical models of fault mechanics in 1978

This site will be an essential resource for the next version of the chaos course. There are two others that will serve as complementary resources…

A debate in Nature titled Is the reliable prediction of individual earthquakes a realistic scientific goal? Moderated by Ian Main, the site is a fascinating give and take on the topic by a number of scientists. For the debate, earthquake prediction is considered in light of one of four scenarios:

  1. Time-independent hazard… in which past occurrences of earthquakes are associated with specific land areas
  2. Time-dependent hazard …in which prediction is based on simple correlative models, including clustering in space and time
  3. Earthquake forecasting … in which forecasts are made based on a precursory signal - say some unexpected plate movement or low-level fore-shock
  4. Deterministic prediction …in which earthquakes are assumed to be inherently predictable.

Main provides a provocative call to arms at the beginning of the debate:

Time-independent hazard has now been standard practice for three decades, although new information from geological and satellite data is increasingly being used as a constraint. In contrast, few seismologists would argue that deterministic prediction as defined above is a reasonable goal in the medium term, if not for ever. In the USA, the emphasis has long been shifted to a better fundamental understanding of the earthquake process, and on an improved calculation of the seismic hazard, apart from an unsuccessful attempt to monitor precursors to an earthquake near Parkfield, California, which failed to materialize on time. In Japan, particularly in the aftermath of the Kobe earthquake in 1995, there is a growing realization that successful earthquake prediction might not be realistic. In China, thirty false alarms have brought power lines and business operations to a standstill in the past three years, leading to recent government plans to clamp down on unofficial 'predictions'. So, if we cannot predict individual earthquakes reliably and accurately with current knowledge, how far should we go in investigating the degree of predictability that might exist?

One person who believes that quakes can be predicted but that current accepted models are hopelessly wrong is geologist Jim Berkland, who claims that his Seismic Window Theory - based on tidal forces associated with Sun/Moon alignment and "abnormal animal behavior" - is a much better predictor. Berkland’s web site - Syzygy Job - is fascinating reading because it not only presents up-to-date earthquake news, but also contains Berkland’s description of his ostracization by main-stream earthquake scientist. In his words:

Despite my successes in earthquake prediction (using tides and abnormal animal behavior), I found it almost impossible to publish on the subject in scientific journals... Mainstream scientists generally try to debunk various aspects of my earthquake predictions or to ridicule me personally, with epithets such as crackpot or clown. My response is to question their own records in earthquake prediction, and to point out that the main action of a stream is not near the center, but closer to the edge. Near the fringes, with eddies and cross-currents, erosion and deposition are more effective, sometimes leading to changes in the course of the stream... The experts of High Science state that earthquake prediction is currently a scientific impossibility. I maintain that the topic is too important to leave to the experts and I continue to do the impossible with a better than 75% battering average , which is more than 300% greater than chance.

"Battering average"? A chance typo, or revealing slip of the tongue, in a field where slippage of tectonic plates is a sign that it is too late to predict - the quake is already here.

Categories Modeling Physics Understanding & Prediction

Constructal Theory of Everything?

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A very interesting text that describes what appears to be a bold new approach to modeling many possible systems - even human ones - is about to be released. Titled Constructal Theory of Social Dynamics and edited by Adrian Bejan and Gilbert W. Merkx, the text "brings together for the first time social scientists and engineers to develop a predictive theory of social organization, as a conglomerate of mating flows that morph in time to flow more easily (people, goods, money, energy, information). These flows have objectives (e.g., minimization of effort, travel time, cost), and the objectives clash with global constraints (space, time, resources). The result is organization (flow architecture) derived from one principle of configuration evolution in time (the constructal law): "for a flow system to persist in time, its configuration must morph such that it provides easier access to its streams."

Begin and Merkx are from Duke. The Duke press release is very enticing - this is certainly a text that will serve as a reference for the chaos and fractals course, or perhaps a primary source.

Some tantalizing tidbits:

Why does a railway network look like a river? Why do the streets of old Rome look like a leaf? Because whether their shape is determined by the interactions of molecules or the choices made by individual humans, all of these systems of flow are governed by a relatively simple new principle of thermodynamics. "Society, with all its layers and features of organization, is a flow system," say co-editors Adrian Bejan and Gilbert Merkx of Duke University. Consequently, these repeating patterns are no accident. "Coincidences that occur in the billions are loud hints that a universal phenomenon is in play." First described a decade ago by Bejan, a professor of mechanical engineering at Duke, the constructal theory is a deceptively simple explanation for why these branching patterns occur so frequently: for a flow system to persist in time, its configuration must change such that it provides easier access to its currents. Simply put, if something is flowing, it will branch in a fairly predictable pattern to reduce imperfections like friction, or in this case, bumping into pedestrians coming the other way. "Natural systems will always move toward faster access or easier flow," Bejan said .... Constructal theory fits well with network theory in sociology and helps explain why the large patterns persist even where there's free will and consciousness.

I had not heard of constructal theory until recently, when Bill Weaver of La Salle’s ISBT program alerted me of the Bejan/Merkx text. Reading more on Bejan’s web site sure makes it sound as if it is the NEXT BIG thing. For further proof, consider the Constructal Theory Web Portal, which lists an amazing range of applications, such as

  • Constructal theory of sociodynamic forms
  • Constructal pattern formation in stony corals
  • Constructal theory of generation of configuration in nature and engineering
  • Constructal theory of droplet impact geometry
  • Constructal theory of particle agglomeration and design of air-cleaning devices

If it sounds as if Constructal Theory can be used for anything at all, you’re not far off the mark. Read Bejan’s The design of every thing that flows and moves for an impressive - (even if there is a bit too-good-to-be-true-ness about it all) projection of a Theory of Everything - that moves, at least.

Most audacious abut the projections, though, is that the 2nd Law need not apply:

The word entropy does not appear in constructal theory. Entropy is the word and concept of the second law of thermodynamics, which it serves very well. The physics covered by the second law is the phenomenon of irreversibility: every thing flows from high to low ... The occurrence of organization (configuration, macroscopic complexity) in nature is an entirely different phenomenon. This phenomenon calls for its own principle and concepts. The constructal law answered this need. The words that appear in the constructal law are the generation of flow configuration, in time.

I am looking forward to more on Constructal Theory - to see whether it can deliver on the exuberant projections. It may be that CT does a great job of predicting - with or without understanding. Meanwhile, I applaud any effort that attempt to find unifying laws of organization, which by definition, will make the modeling of many more situations conceivable in principal.

Of course, this may mean that chaos theory itself has to take a back seat to constructal theory. If Bejan had his way, chaos would be left off the bus, as can be seen from his interview in Seed magazine:

"What I'm telling you is totally, let's say, the upside-down of what the proponents of chance and non-determinism have been promoting for more than a hundred years." Bejan said. "This is—how should I say—the end of the story. The end of the argument. A law of physics that says it all, and it takes less space in a future physics book than all this debate that currently has led to things such as chaos and chance and fluctuations and turbulence and other buzz words that mean 'I don't know.'"

Them’s fightin’ words…

Categories Chaos Evolution Modeling Physics Science Understanding & Prediction

In Search of the Fastest Rubik's Quark in the World

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Magnetic/Acrylic Rubik by NTronicsThere’s a great scene in the Pursuit of Happyness in which Christopher, the protagonist played by Will Smith, becomes infatuated with his son’s Rubik’s Cube, and ultimately goes on to be a Cube Solver. In a chance encounter with a stockbroker he is trying to impress, Chris/Will solves the cube - a feat that blows away the broker, and which leads to an interview, and then…I won’t go on here - rent the movie, it is a good one, and based on a true story.

Back to the Cube. Jessica Fridrich of SUNY Binghamton, who completed a Ph.D. in non-linear dynamics (Removing observational uncertainty from orbits of nonlinear dynamical systems) is something of a cube speed freak. Consider that she won the First Czechoslovak Championship in Rubik’s Cube in 1982. At the top of her game she " routinely solved the cube in an average time of 17 seconds…actively using more than 100 algorithms." You’ll find some of her solution techniques and algorithms here. You’ll also find links to other speeders, including sage advice on how to grease your cube.

Click here for the official list of cube speed record holders. The current fastest is 10.48 seconds by Toby Mao of the US who solved the cube in 10.48 seconds at the 2006 US National Championships in San Francisco. (The 10-second cube must be the analogue of the 4-minute mile.) A more fun list is of unofficial records, which includes the fastest times for cube solving in such exotic categories as blindfolded using one-hand, feet only, and underwater.

Shortly after the cube became popular, I remember reading a Scientific American article that described a deep connection between possible cube configurations/operations and particle physics - specifically quarks and quark confinement. This was based on the work of Solomon Golomb of USC (he may have been the author of the article - I have not been able to find it by searching).

As recounted by William Bader:

Solomon Golomb of the University of Southern California relates twists on corner pieces to elementary particles made from quarks...Quarks have fractional electric charges of 1/3 and 2/3 the same way that corner pieces on a cube can have twists of 1/3 and 2/3. Positive charges correspond to clockwise twists, while negative charges correspond to counter-clockwise twists. Quarks always combine into particles with an integral charge; a quark and anti-quark pair form a meson, while three quarks form a baryon. For example, a proton is a baryon with two up quarks and a down quark, while a neutron is a baryon with one up quark and two down quarks. In the same fashion, unless you take a cube apart, the twists on the corners always add up to an integral value. You can twist one corner clockwise and another counter-clockwise, or you can twist three corners in the same direction, but you can not twist a single corner alone, and you can not twist only two corners in the same direction. This is the Rubik's Cube analog to quark confinement. It is possible that someone living in a higher dimensional space could reach into our universe, extract a lone quark, and return it in a different state, the same way that you can remove a corner from a cube, twist it, and then put it back. A person (or, in the case of some of my cubes, a dust bunny) living in the world of a cube could calculate the patterns that could be made from a cube with a twisted corner without ever having the means to construct a cube with a twisted corner.

The reality of quarks has always been a bit iffy - do they exist, or do quarks merely provide a model that allows for some understanding/prediction? Which is why the use of the cube as a model for understanding quarks is quite ironic - the cube as model of a model.

With speed to burn.

Visit Ntronics to purchase your own magnetic/acrylic cube.

Categories Chaos Mathematics Modeling

Bad News Polar Bears with Business Intelligence

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Bad News: Walter Matthau and BearModeling can’t exist as an urgent, necessary, and successful activity without some agreement about the data that is used to verify the model. Monitoring the loss of Arctic sea ice is a relatively unambiguous measurement: take some pictures and measure what you see over a stretch of time, looking for a trend.

For anyone not themselves lost in the Arctic for the past year or so, the sight of polar bears hopelessly afloat on shrinking bergs is an iconic image that is a powerful image of the immediate consequences of global warming.

A natural question needs to be asked - if the arctic ice is shrinking, does that mean that each polar bear has less ice as the arctic approaches the population density of New Jersey, or does the number of polar bears decrease to match the decrease in ice?

Counting bears is much more ambiguous - and dangerous - than measuring photos of ice. What’s needed is a protocol that doesn’t miss any old bears, and new bears, and especially the lack of bears that brings bad news.

A really interesting approach is provided by Wildtrack - an environmentally conscious group that puts its methodology where its mouth is, having developed a patented technique of non-invasive wildlife monitoring. The technique uses business intelligence software (basically enterprise software such as SAS) and "ancient tracking techniques of the Inuit people to study polar bear footprints." Click here for more on this story.

Now the question is whether the data provided by the Wildtrack system will be considered valid by those who automatically assume any environmental group will always overstate the effects of humankind on animals and the environment.

No one needs a sophisticated software approach to count these skeptics/cynics. Election results and make-up of the bodies of Congress are usually a good predictor of who will agree that the data is valid, and who won’t. Actually, the congressional make-up is also a good predictor of the percentage of the population that won’t accept any science-based conclusions at all.

Just count the footprints of those fighting global warming solutions and stem-cell research…

Categories Modeling Politics

Cosmic Legos

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Escher Legos. Click to enlarge.In his book God’s Universe, Harvard astronomer Owen Gingerich attempts to reconcile intelligent-design and evolution. This seems to be an almost impossible task, so I was curious as to how Gingerich would approach this division.

Unfortunately, the reviews and descriptions I have read leave me bewildered because Gingerich’s argument seem to be of an anticipated form, namely that God created the laws and then let everything develop on their own.

Gingerich does riff on the idea that the physical constants and various energy levels of appropriate atoms are so fine-tuned as to allow life - (shades of the anthropic principle!) that there is some "higher purpose." So what then is different in his argument from intelligent-design? God created the building blocks and the physical laws and just stood back and watched. This is not so different from the views of many scientists, so I’m not sure where Gingerich is headed that adds anything to the debate. Unfortunately, in the quotes I have read, he does seem to rely on an unsubstantiated claim of an underlying imperative for the existence of our universe, and, by extension, all of us:

"There may be no architect with a plan for the final product, but there is the designer of the set of little interlocking parts. And the existence of the set itself cries out for something to be built with it," he writes, "like having a giant and very complex Lego set supplied without a blueprint."

Sorry - this argument is a shade too teleological for me. It seems unlikely that a strict I-D supporter would include Darwinian evolution as a God-willed/designed process. Similarly, would a strict Darwinian soften in terms of allowing a little bit of design to creep in - even if just to jump start the whole evolutionary process?

I doubt it, although the latter may be more probable. Some Darwinians would probably go along with this idea because it is basically unverifiable, and hence not in the realm of science. As long as God doesn’t reach in and tinker with the cosmic Legos, they’ll most likely concede the point in order to proceed with their own research from a slightly higher ground.

At the very least, the Lego reference is always sure to fire up the imagination of anyone who had a set when they were young. It sure seemed then that anything - from houses to trucks to people - could be built out of the same Lego-stuff. The Lego diorama of Escher’s Relativity appearing at the top of this post shows that Lego-stuff can be used to model non-existent worlds also. Created by Andrew Lipson, Relativity is only one of his amazing Lego renditions of some of Escher’s most famous works.

Categories Evolution Religion

Relative Time and Swiss Clocks

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The recent books on Einstein by Isaacson and Neffe (see reviews) cover the development of special relativity in great depth, with special attention to the development of an operational definition of time duration that vanquishes the prior notion of simultaneity. Indeed, simultaneity is now accepted as observer-dependent, thanks to Einstein’s Special Theory.

Both books do refer to the role played by Poincaré- although "role" is not necessarily the operative term here. No doubt Poincaré was thinking deeply about time, but did not make Einstein’s leap to codify the relative nature of time duration.

An excellent book on the Einstein/Poincare connection is Einstein’s Clocks, Poincaré’s Maps: Empires of Time, by Peter Galison. Here Galison tries to relate Einstein’s experience as patent clerk who most likely saw patent proposals for clock synchronization between different Swiss cities to his ongoing thought -experiments in the foundations of physics. ( In a generally very favorable review by R. Wald for Physics Today, this idea is called into question.)

But the Poincaré connection is fascinating because it is not clear to what extent, if any, Poincaré’s writings on time were even seen by Einstein. (And the title of the book is itself a play on words, because a Poincaré Map is a fundamental analysis/visualization tool of chaos and fractals.)

The new Einstein bios have really opened up new avenues of thought on how Einstein came to be Einstein. The Poincare connection is fascinating, and a potentially important piece of the answer.

Most amazing of all is the pictures these books paint of the intellectual ferment taking place in Europe at the end of the 19th and beginning of the 20th century. It is hard to imagine a similarly exhilarating time of new, earth-shattering theories that can possibly duplicate these years for excitement and creative brilliance.

Categories Chaos Philosophy Physics Visualization

Newtonian Determinism and Pathological Aloneness

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Newton’s Alchemical manuscript. Click to enlarge.Newton’s Laws applied to physical situations describe a Universe that is totally deterministic. For scientist-modelers, the canonical methodology for predicting future events is based on Newton’s process: stuff the initial conditions of a system into the appropriate "laws", and let time increase in the resulting equations of motion. Here’s your prediction as a time series extending as far out into the future as you need. Next problem!

Chaos theory does not violate this Newtonian modeling process. Instead, chaos demonstrates that the equations of motion are so non-linear that small inaccuracies in the initial conditions lead to wildly varying future predictions - the so-called sensitive dependence on initial conditions that is the foundation of the butterfly effect. In effect prediction becomes limited in many situations, with weather one of the chief systems where predictability is desperately needed, but often leaves all of us wondering where the TV weather people ever got their degrees…So prediction is diminished, even though determinism is as strong as ever.

I was thinking about Newton’s legacy of determinism as I read a piece on Newton written several years ago by James Gleick for Slate, titled Isaac Newton’s Gravity. Gleick, the author of the text that brought Chaos to the masses (Chaos - The making of a new Science) is also the author of a well-received 2003 bio of Sir Isaac.

Gleick argues convincingly for the need to display Newton’s achievements in the context of his rather bizarre life (of which the pathological aloneness in the title of this post is one of Gleick’s signature descriptions). In this his approach reminds me very much of the recent biographies of Einstein.

Was Newton as methodical as the way physics is now presented seems to suggest? Were his life, beliefs, etc., a product of immutable beliefs and processes?

It may be that superstitions were more apt. With his "obsession with alchemy and theological heresies" Gleick writes that "we misunderstand Newton if we imagine him as a paragon of rationality and public science in the modern style."

This contradiction between the clockwork universe of laws, initial conditions, and deterministic futures, and the swirling passions of Newton’s studies suggests that there is some truth to the often-found "madness & genius" mix.

For me, reading about Newton and trying to imagine what physics would be like without him is simply impossible. Would our ideas of determinism be as strongly fixed if calculus and differential equations had not arrived until much later? (assuming the Leibniz did not produce the physics breakthroughs with his flavor of calculus.) Would Chaos Theory be as significant? Would we even need it? Maybe not - perhaps some of the linearizations that appeared along the way as Newton’s Laws were applied to certain intractable non-linear situations would not have occurred. Maybe we would learn non-linear equations on an equal footing with linear equations.

All of this is an interesting thought-experiment. But Newton did live,and create magic with his laws and mathematics - even though he may not have been ready for the universe he himself created. Gleick recounts a remarkable view of Newton by John Maynard Keynes:

"Newton was not the first of the age of reason," Keynes said. "He was the last of the magicians, the last of the Babylonians and Sumerians, the last great mind which looked out on the visible and intellectual world with the same eyes as those who began to build our intellectual inheritance rather less than 10,000 years ago." Newton opened a door to our world, sure. But he belonged to the world we have left behind."

Again, there are similarities to Einstein, only he just had the 200-plus years of Newtonian physics to overthrow. With his quixotic attempts to argue against the probabilistic realty described by quantum mechanics, his fundamental belief in determinism and causality, he too belonged to the older world - of Newton.

Categories Chaos Determinism Modeling Physics Understanding & Prediction

Empirical Prayers & Logical Fallacies

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In Prayer: A Neurological Inquiry Skeptical Inquirer author David Haas asks "Are silent prayers transmissible to, or readable by, a supernatural being?" He then attempts to answer this question using "modern information about the brain."

Haas makes a distinction between thoughts and prayers and the underlying brain activity, stressing the non-naturalness of the prayer processes:

"The brain, an electrochemical organ, consists of matter and energy, but the mental states that are the epiphenomena of its physiological processes are neither material substances nor forms of energy …If thoughts—including silent prayers—are not a form of energy, then there is no known natural means by which they could be transmitted beyond ourselves or read within us. "

Haas then gets to his main question - "Though thoughts and prayers are neither transmissible nor readable by any natural means, could they be known to a supernatural being?"

This is a provocative, $64,000 Question, one which cannot be answered to anyone’s satisfaction, but one that leads to all sorts of meta-issues involving all-knowing and all-powerful deities.

Unfortunately, Haas trips up immediately. Here’s how he wishes to answer the question of whether prayers can be known to a supernatural being:"Evidence for or against this can be obtained by determining whether prayers are followed by what was solicited by them."

That is, Haas wishes to base his conclusions on whether or not the prayers were answered. He goes on to cite a number of studies that have failed to find a therapeutic effect of intercessory prayer. (In a previous post I noted that The Templeton Foundation had funded one such study. )

The fallacy of Haas argument is stunning - just because a prayer is not answered does not mean that it was not sent, and/or that it was not received. Note that the reasoning would cut both ways: if there had been some therapeutic effect found, it would still not verify that a supernatural being had received the prayers and acted on them.

Haas makes some interesting points about actual brain activity, but again ends with a totally unsupported conclusion:

"Whether they can be known to a supernatural being hinges on the effects of the prayers’ solicitations as judged by proper scientific studies. To date, such studies of intercessory prayer have not shown it to improve health-care outcomes. In contrast to thoughts themselves, the brain activity from which thoughts arise does consist of energy—electrochemical energy within neural circuitry. Reading this teeming energy in millions of circuit neurons and translating it into the thought or prayer arising from it seems theoretically impossible for even a supernatural being."

Unfortunately, Haas’ article just muddies the Religion/Science debate. Neither side benefits from illogical arguments.

Categories Religion Science

Strange Bedfellows in the Climate Change Debate

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Chaos Theory by Chromasia.com. click to enlargeAn excellent web site titled The Discovery of Global Warming is provided by the Center for History of Physics of the American Institute of Physics.

Created by Spencer Weart, the Director of the Center, this is the best site I have seen on climate modeling and climate change by far. Fully hypertextual, you’ll find everything from the first mention of greenhouse gases to political ramifications and chicanery, to a very detailed description of General circulation models.

But the best is the section on Chaos in the Atmosphere , which provides an enormous amount of detail on atmospheric modeling well before Lorenz, and well beyond. From the intro:

...in the 1950s, work with slightly more complex physical and computer models turned up hints that even quite simple systems could lurch in unexpected ways. During the 1960s, computer experts working on weather prediction realized that such surprises were common in systems with realistic feedbacks. The climate system in particular might wobble all on its own without any external push, in a "chaotic" fashion that by its very nature was unforeseeable.

Skeptics of global warming usually fixate on the idea behind the statement "the climate system in…might wobble all on its own without any external push, in a "chaotic" fashion that by its very nature was unforeseeable." They’ll use this to discount any effect of carbon emissions, i.e. human-produced climate change.

The situation is tricky. One can’t accuse climate-change deniers of not accepting a scientific model of climate change. Instead, they are using the results of accepted scientific modeling, which appears to show that chaotic variations in climate are to be expected without any human influence.

Weart does a great job of addressing this issue. I’ll try to summarize here, but there’s no substitute for reading the full article (which I will definitely include as a reading in my upcoming Fall 2007 version of Chaos and Fractals.

Until the future actually came, there would be no way to prove that the modelers understood all the essential forces. If an unlucky combination sent the real climate temporarily into one of the unusual states found in some model runs, that could confuse people about what was happening. But it was not likely to change the eventual outcome. What was no longer in doubt was the most important insight produced by the half-century of computer experiments. Under some circumstances a fairly small change in conditions, even something that seemed so slight as an increase of greenhouse gases, could nudge climate into a severely different state. The climate looked less like a simple predictable system than like a confused beast, which a dozen different forces were prodding in different directions. It responded sluggishly, but once it began to move it would be hard to stop.

The most important point Weart makes comes from one of the basic tenets of chaos theory: even a little bit of greenhouse gas emissions could be enough to put the climate system into a chaotic state. If the climate system is indeed chaos, it won’t take much to cause it to cycle wildly. there is no disagreement that the models themselves are chaotic. There is no disagreement that our climate is chaotic (and, as mentioned above, the climate-change deniers implicitly treat our climate as chaotic - prone to erratic behavior based on its internal dynamics alone. So why should anyone disagree that reducing greenhouse gases is a wise thing to do? Because they implicitly accept the fact that the climate is chaotic, they also must accept that small perturbations can make things much worse.

Only a cynic would point out that deniers often have a financial stake in the continued use of certain fossil fuels.

Categories Chaos

Cross-Species DNA and Accelerated Evolution

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Protein molecular evolution. From M. Deem.A recent article in the May 2007 APS News describes the use of a physics model to understand accelerations in evolution that occurred between the appearance of 1-celled organisms 3.5 billion years ago, multi-celled organisms 1 billion years ago, and everything other organism that has since appeared on earth in only the last billion years.

The modeling is by Michael Deem of Rice U. His model allows for "cross-species genetic exchange" - in effect DNA from one species is adopted by another which then realizes an evolutionary advantage. Successful DNA adoption is called HGT - Horizontal Gene Transfer. Deem’s approach is based on field-theoretic techniques. The net result: species can evolve much quicker because they contain fully-functioning "genetic modules" from another species. The implications for our own genome are startling, and it may be that a "significant portion of our DNA was donated by viruses and bacteria that infected our ancestors" over millennia.

In addition to evolution, Deem and his team are researching the immune response to viruses and vaccines, cystine-knot antimicrobials and the innate immune system, and the structure and nucleation of zeolites, using an assortment of models grafted from physics research. The physics of nuclear spin glass modeling is used in the virus work, e.g.

Deem’s research itself if a meta example of HGT - the use of physics models in biological systems.

The work on evolution is incredibly important. If not already, it will soon be attacked because of its controversial suggestions and, most important, success. I’m sure that creationists and intelligent design proponents are up in arms about anything showing that it is indeed possible for incredible complexity to develop in a Darwinian way in a relatively short period of time.

Not to mention sharing DNA modules with rather unsavory creatures and even lower forms of life.

For Deem and his research team, it’s just another example of physics as a way of life, and a way of understanding life.

Keep on modeling.

Categories Evolution Modeling Physics