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Albert N. Schellekens wrote a popular 87-page preprint,

The emperor's last clothes?

It is clearly a popular text but yes, indeed, it is way more technical than some books that are considered by their authors to be more-than-popular. ;-)



Wordle...

Schellekens, together with Dieter Lüst and Wolfgang Lerche, wrote a paper or two in the 1980s that argued that the number of vacua in string theory was huge, comparable to 10^{1500}. So if this insight is a discovery or a "paradigm shift", they should surely be included among the fathers of this idea. Well, I am not among those who would think that these "fathers" should be excessively proud about something or even fight for priority! :-) They just wrote a high number (an upper bound) whose derivation was not quite correct and whose philosophical consequences seem irrational to me (and at any rate, they were proposed centuries ago).

At the beginning, Schellekens criticizes the people who now say that they always knew that the number was huge but they didn't find it important enough to talk about it. ;-) Well, I think that his criticism is legitimate and I am not among the people criticized by Schellekens because I never thought that the number was that huge - even though now I think it is probably true - and I do think that this question is somewhat important: those who "knew" it shouldn't have been silent. But I also think that the large number of the vacua itself doesn't imply the anthropic reasoning.

So while there is a sense in which the anthropic principle is a very old story and no contemporary scientist should sell it as his discovery, it is also true that only the stringy flux compactifications that were found in this decade have made the possible anthropic picture of physics "complete". Even though string theory doesn't really imply that the anthropic reasoning is correct, it is also the only framework we know where the numerous vacua may be classified and co-exist in a huge multiverse. String theory offers the only satisfactory incarnation of the anthropic reasoning. As many other important keys, string theory is able to open the gates to the Heaven as well as the Hell.

Is uniqueness the same thing as anthropocentrism?

But as you can guess, I disagree with Schellekens' main theses. The anthropic principle is neither something we should be happy about (Schellekens views it as a victory of string theory and related breakthroughs) nor something we should feel certain about. However, this debate is not just about one-sentence "opinions" and even in his popular text, he has written 87 pages of somewhat insightful arguments. I won't offer you 87 pages but we will look at many of them, anyway.

First, there exist two full propaganda machines justifying the anthropic principle or, on the contrary, the possibility to find the full, unique, and complete laws governing the Universe (monovacuism, if you wish). Schellekens also dedicates a few pages to this propaganda - and various funny and subtle kinds of criticism invented by the physicists in both groups.

The anthropic people including Schellekens and Susskind claim that the "landscape revolution" is analogous to the Copernican revolution and other revolutions in science: stupid people used to think that they were terribly important (they believed in anthropocentrism) but brave scientists have shown that the humans were not so special, after all. The Earth is not a center of the Universe, and neither is our Sun or the Milky Way. The human DNA is not qualitatively different from the DNA of other animals. And perhaps, our Universe is just one among zillions of universes in the multiverse. The properties of elementary particles can't possibly be unique, can they? The Universe is a mess and it has always been one. :-)

Well, that's one story. But I also see a completely different story involving more recent breakthroughs in theoretical physics that are arguably more relevant for the question of predictability of the particle masses than Copernicus' adventures. During the last century or so, we have seen an incredible unification of concepts and observations that eventually allowed us to describe all of chemistry, engineering, and biology (thousands of materials, objects, and their diverse interactions) in terms of a single theory (QED) with one dimensionless parameter, the fine structure constant (and perhaps the proton-electron mass ratio), and even if you're interested in the other physical effects that are pretty much irrelevant for life (such as nuclear physics), we can describe everything by a similar theory with 28 parameters (the Standard Model; plus add General Relativity in a sloppy way to separately describe the gravitational phenomena). It is natural to expect that the missing step to complete the picture is analogous e.g. to the electroweak unification and it will make the remaining parameters calculable, much like the spectral frequencies of all atoms became calculable 80 years ago, and we seem to be damn close to completing this step. The Universe is elegant and it has been elegant even before the first moment when people noticed. ;-)

These are stories about two scientific "trends". These trends seem to have the opposite "signs". They are "derived" from our experience at different time scales. They are "derived" by selectively focusing on some stories while neglecting and humiliating others. I think that every rational person realizes that the answer to the question whether the anthropic explanation of the Standard Model or its unique derivation from a fundamental theory is the right approach doesn't necessarily have to mimic the answers to "similar" questions answered by Copernicus. It doesn't have to "reproduce" the uniqueness of QED, either. We are simply asking different questions than the previous generations and different questions sometimes have the same answers but they often have different answers. For example, the world has been increasing in size in Copernicus' and Hubble's time but so far it has never increased behind the boundaries where we can actually see anything. Many quantities - such as temperature - were shown to depend on the environment (distance from the Sun etc.) but it still seems that the particle masses and couplings we want to calculate are universal across those 14 billion light years of the visible Cosmos.

And the uniqueness has worked in fundamental physics but there are many stories close to fundamental physics where it didn't work and where we believe that historical coincidences played a critical role in determining some parameters.

I say that all sane people must be aware of the fact that we can't "derive" the answer to this completely new question by extrapolating the previous experience. But at the same moment, it seems that many people try to pretend that they believe that such an extrapolation is possible. Sorry but as long as you focus on rational arguments, such an extrapolation is impossible. There's no way to be sure. The "uniqueness" answer hasn't been proven; it is probably necessary to actually find the correct unique answer before we will know that the answer is unique. ;-) And the "anthropic principle" hasn't been proven, either. Whoever thinks that he has a simple philosophical proof of his attitude is sloppy. And whoever thinks that his answer must be correct because all other answers can be defined "not to be science" is an imbecile. And Nature doesn't give a damn how imbeciles define science: Not Even Woit.

When we discuss these anthropic questions, there exist various technical differences between field theory and string theory: string theory actually allows us to define the measure on moduli spaces, count the discrete vacua, and connect them to a unified cosmology via the eternal inflation and tunneling. Because the stringy realistic vacua are discrete, they are more specific and, in principle, completely localizable (even though one of the points of the anthropic approach is that you shouldn't even try to do it). Nevertheless, the deep essence of the anthropic argument seems to be identical in field theory and string theory. So we can ask:

Can the Standard Model parameters be derived from a fundamental theory?

We don't know the answer. Once people actually derive them, the answer will clearly be "Yes". The anthropic people say that the answer is almost certainly "No" and the rest of us says that their conclusion is premature.

Schellekens describes the reactions of the anthropic infidels as disgust (or even religion!) :-), denial, and derision but he also mentions that Burton Richter considers the anthropic people to be creationists. By the way, it is actually very subtle which group is closer to creationism: it depends on your optics.

Schellekens recalls some of the anthropic coincidences that seem to be necessary for life and offers us an anthropic checklist - four steps that help a careless reader to wash his brain and become an anthropic person, too. ;-) The checklist is rather clever, so let us look at it:

1. The Standard Model may not be the unique mathematical solution of any fundamental theory.
2. Not all alternative solutions allow observers.
3. The total number of solutions should be sufficiently large to make the existence of a solution with observers plausible.
4. We live in the most probable Universe which allows observers.

Why is it clever? Because he is "gradually" making the propositions "more anthropic" and the last one is nothing else than the hardcore anthropic assumption that people like myself clearly want to reject. However, I kind of accept the first statement. So where should I say "No" for the first time? It is actually hard to find the place. But I will find it in the middle of the point (3), anyway. ;-)

First, I tend to agree with (1). I find it unlikely that a fundamental theory - or even string theory with a selection mechanism - would make the rather messy Standard Model (with its parameters) a completely unique solution. After all, we know many other solutions to string theory and I am convinced that many (or most) of them will survive the test of time.

The statement (2) is almost clearly correct, too. For example, some stringy vacua with unbroken supersymmetry can be almost proven not to have any observers or intelligent observers. We don't have a full proof of it - because we can't really define observers and classify all conceivable "types of life" - but it is plausible that we could construct such an argument. One of Schellekens' powerful tools is to emphasize that we don't have to prove that "our island" in the parameter space is the only place that admits life (which seems extremely hard to argue because there can be discretely many "types of life"). It is enough to show that there are many generic places outside that almost certainly don't admit life.

Now, because I have accepted the points (1) and (2), Schellekens says that I have already adopted "some kind of anthropic reasoning" because there are places (different universes) where we don't live. Well, fair enough. It is "some kind" but I still haven't accepted (4), have I? :-) Just the fact that I don't live in the middle of ocean doesn't mean that I can't exactly calculate the the number of protons in the atoms dominating our atmosphere (nitrogen).

I kind of agree with the binary content of the point (3), too, but the precise explanation why I agree could be highly disappointing for Schellekens. If we make an estimate of the probability (or plausibility) that life is born somewhere in the multiverse allowed by the fundamental theory, the probability shouldn't be much smaller than one. The life shouldn't be a completely unexpected accident according to science.

However, one must be very careful how this probability of having life somewhere is calculated. Schellekens is now slowly trying to convert the readers to the irrational anthropic reasoning, in order for them to accept (4), too. Why? Because he wants you to believe that the probability that the life exists somewhere - among N universes - is essentially equal to N times P where P is the probability that the life is created in one "typical" universe (the formula gets corrected if N times P would be close to one or greater than one).

This could be a good order-of-magnitude estimate in an "egalitarian" multiverse where all universes have the same chance to host observers. But I think that this "egalitarianism" is simply incorrect and it is very important for this whole anthropic debate that this principle is incorrect. In fact, I can make the accurate calculation of the probability that a correct fundamental theory allows for observers somewhere on its landscape: the probability is not N times P but rather 100%. It's that simple.

We know that life exists, so if the theory is correct, it must predict life inside one of its solutions. The only problem could occur if no fundamental theory existed at all, but I choose to discard this possibility. If we only want to know whether it predicts life or not, it doesn't matter how many classical solutions it has and what is the distribution of the probabilities that each of them allows intelligent observers. What matters is that it contains at least one universe - ours - that admits life.

This "N times P" calculation is sloppy, ideological, and this ideology - the egalitarianism between vacua that are clearly different, non-equal, and hierarchical in many respects - is the essence of the anthropic fallacy. In my calculation, I didn't even have to multiply two numbers: you might think that it makes my calculation less mathematical. However, my result is actually exact, unlike the results of Schellekens' implicit formula.

It is interesting to look at Schellekens' calculation of the probability in (3) from one more viewpoint. He seems to require that the density of the stringy vacua in the vicinity of our region of the Standard Model parameter space should be huge, otherwise it is awkward to believe that any vacuum of string theory matches reality. I fundamentally disagree with this proposition. Here is my checklist to see why this proposition is irrational:

• The density of the stringy vacua near our locus in the SM parameter space is not infinite because the number of semirealistic stringy vacua is finite: so Schellekens can never be "completely satisfied".
• When you try to find out a "natural lower bound" for the density, you won't find an acceptable answer. For example, you might require that the small region that describes our Standard Model with the error margins of parameters as extracted from the 2008 measurements should contain at least one stringy vacuum, if calculated by the densities. But this "falsification" would clearly be irrational because such major decisions about the validity of a theory cannot depend on the number "2008" or some random coincidences about our present world.
• Moreover (and the following argument is related to the previous one), sometimes in the future, the measurements of the SM parameters will be more accurate, the error margins (and therefore the relevant region) will be smaller, and the number of vacua calculated in the "ball" around our point through the densities could drop well below one. In the future, the "test of sufficient density" is likely to fail even if it passes today. Sometimes in the future, this "density" test will fail. If you know so, shouldn't you agree that the test is failing already today?
  
• Once you agree that there exists no "sensible" lower bound on the density of stringy vacua near our locus, you will realize that it should have been completely expected that this criterion was nonsensical from the very beginning. When the density of stringy vacua near our point is (much) lower, it simply means that string theory will be (much) more predictive when it comes to the Standard Model parameters. There is nothing wrong with a theory that is more predictive. We have always believed that we were looking for predictive theories and if the supposed "paradigm shift" is that we must require the theories to be unpredictive, I simply disagree. Schellekens seems to believe otherwise: he thinks that every theory that is predictive is excluded and only theories that can be adjusted in any way to match the observations by chance are allowed. I beg to differ.
• To summarize, the only sensible "phenomenological" way to falsify string theory (or another hypothetical theory with many vacua) is to show that the number of vacua in the vicinity of our locus in the SM parameter space, plus minus the known error margins, is strictly equal zero. Any other "falsification" claiming that the density seems "too low" is a fallacy based on the (ludicrous) assumption that theories are never allowed to predict anything.
  

While in (3) this fallacy was incorporated "silently" - the point (3) was written so that you make the "N times P" error yourself - it is written explicitly in point (4) which is nothing else than a logically and scientifically unjustifiable left-wing propaganda.

Let me say one more comment. The anthropic selection could be "partially correct" etc. but even if it is so, the interesting observations are the aspects in which the anthropic reasoning is incorrect. This is where the new patterns and new scientific insights are located. So it would be highly counterproductive to assume that the anthropic assumptions of genericity are "nearly universal".

And one more observation about the point (3). I calculated the probability that a viable universe is somewhere in the landscape of the fundamental theory. That was equal to 100%. But if I give you a Hartle-Hawking-like cosmological selection criterion, it secretly assumes that only one universe gets materialized, not all of them simultaneously, and the formula can produce a different probability for the realization of a (any) universe - and a different formula for the probability that life emerges. The result could be much smaller than 100%. That's true. But what is not true is the implicit assumption of the anthropic people that if I require the probability to be calculated in this way and if I want the result to be close to 100%, I must allow (almost) all vacua on the landscape to contribute. The final section of this essay describes a very dramatic scenario how the probability could be high even if the vast majority of the landscape had a highly suppressed weight in the probabilistic measure. But even if you find the scenario unlikely, there exist less dramatic possibilities where only a tiny fraction of the landscape contributes.

So the answers are

1. Yes.
2. Yes.
3. Yes, but the answer is trivial and the very question tries to make you accept a wrong formula.
4. No.

The proponents of the anthropic fallacy, including Schellekens, are just not ready or not willing to admit that various calculations they make are just order-of-magnitude estimates that incorrectly assume that certain functions are constants in vast sets of vacua (or in cubed or hypercubed miles of the multiverse). But these quantities and densities of life etc. are not constant. The more we know about the theory, the more we know about the non-constancy and the more accurate calculations we can make. The more we know, the further we are from the fuzzy anthropic ideas about the location of our vacuum in the landscape. It is the very goal of scientific progress to get as far from these fuzzy pictures as we can.

In order to show how political, vague, and socially dependent the anthropic methods are, let me consider the following gedanken experiment. Imagine that you establish a new country and you invite 100 million settlers. Now, the question is: What is the expected number of Fields medal winners? The anthropic people would divide the population by the world population, multiply it by the total number of the Fields medal winners who are alive, and they would get something like 1 Fields medal winner.

But what if I tell you that 99 million settlers are female? Now, it will be an inconvenient question for the left-wing anthropic people. Some of them will say that the probability hasn't changed at all because the sex doesn't matter. The more reasonable ones will make a new calculation and their estimate will decrease by a factor of 100 because there are no female Fields medal winners which is why only the male ones contribute to the expectation value: their total expected number of Fields medal winners will be smaller than one, essentially zero.

Eventually, someone manages to look at the people and among the 1 million of the male settlers, they find Witten, Tao, and Connes. So the correct answer is 3, after all. But the previous estimates turn out to be useless.

The procedures to quantify the phenomenological viability of the multiverse and its subsets are completely analogous. The more we know, the more irrelevant the initial estimates become. And they often turn out to be completely wrong. The anthropic people usually assume that certain quantities, densities, and probabilities are constant for all members of vast sets. But it matters how finely you divide the set into subsets: will you allow your grad students to count the F-theoretical flux vacua and heterotic vacua (or males and females) separately? If you want to get the accurate result, you should divide it to the individual members and do the exact calculation.

Let me mention another, more physical example explaining why we often need to know the exact (or almost exact) answers. The fusion in the Sun is important for our lives but it can only work well if the mass of the helium nucleus is slightly lower than the mass of two protons and two neutrons in the two deuterium nuclei (apologies for oversimplifications, this example is easy to talk about). But you might think that these nuclei are generic states of QCD and by dimensional analysis, the difference of their masses is comparable to the QCD scale. That would generate too high temperatures and maybe other problems. However, the argument is wrong. The energy generated by fusion is comparable to 1% of E=mc^2 only.

And I don't need to assume life to find the 1% figure: a better calculation rooted in QCD or nuclear physics is enough. Some "deeper" patterns that go beyond order-of-magnitude estimates are often damn important for figuring out whether a physical system allows life, among other things. Assuming that all vacua in the landscape have the same probability to host life is analogous to the assumption above that all energy differences in nuclear physics are comparable to the QCD scale. They're not and in many cases, there is a very good scientific reason (not just chance or the requirement of life) why some of them are much smaller.

The very program of the anthropic approach is to forget and deny all deeper patterns and all more accurate and more detailed calculations, to replace our sharp picture of the world by a permanent colorless uniform fog of ignorance. The very goal of this ideology is to convince physicists not to improve their understanding of Nature and to replace exact calculations by low-brow order-of-magnitude estimates. The anthropic reasoning hasn't worked in previous scientific revolutions because more specific explanations were always found and the idea that it is exactly around 2008 when the sharp answers disappear and the anthropic fog becomes relevant for all open questions is a form of fine-tuning. There is no reason for the number 2008 to play such a special role in the scheme of the Universe. ;-)

The assumption that all vacua in the landscape have the same probabilities etc. and we must live in a vacuum in the class that dominates the "total number", whatever the artificial boundaries of the class should be, seems obviously false to me. There exist all kinds of hierarchies, including hierarchies that have neither an anthropic explanation nor a universally acceptable scientific explanation (such as the QCD theta-angle), that show that our vacuum is not completely generic. We kind of know that we have three generations (or the Euler character of a Calabi-Yau) and with further high-energy experiments, it is plausible that we will be able to "measure" other invariants describing the correct compactification, its topology, the numerical values of fluxes, the number of branes, and the shape of the throats. The idea that there can't ever be progress in science is also ludicrous and it's been falsified zillions of times. The only question is how fast the progress will be. We're not guaranteed anything.

The idea that we must live in the "gray" zone of the "most generic" and "uninteresting" vacua could be a great theory for insect in China because it may be the most numerous group of living objects, classified by their country and their class in the Linnaean taxonomy. But this theory simply doesn't look good enough for certain mammals in the Czech Republic.

Schellekens and other anthropic people say that they would be worried if some feature of our world were not "generic" in the stringy vacua - a point analogous to their requirement of a "high density" near our locus. I would not be worried because there exists no law that we would have to be generic. After all, the exact properties of our life and our nationality require the exact vacuum we live in, despite the low density of vacua around (or despite the low population of the nation). But even if someone convinced me that our vacuum should be generic (in "most aspects"), I don't think that anyone knows what the right measure to determine the genericity should be: the "each vacuum has the same vote" measure is surely not good enough because of many reasons, for example because the total number of all vacua (including the AdS5 x S5 vacua) is infinite and the uniform probability measure can't be normalized. It is even wrong to use the counting based on volumes of the Standard Model parameter space because the Standard Model is clearly neither the first nor the last effective field theory that can be written down: it only corresponds to the state of our experimental knowledge of particle physics as of 1973-2008. The QED used to have a smaller parameter space and the MSSM or other future effective theories will require different, possibly larger parameter spaces.

Because the anthropic people rely on so many concepts that are only relevant in 2008, what they're doing is a statistical interpretation of the history of physics, with a focus on the present era, not physics itself. Note that I am in no way saying the "same thing" as Peter Woit. I am actually finding particular material flaws in various arguments while the obnoxious repetitive crackpot only says (731 times) that none of these things is science and he doesn't even have to think about any of the arguments - which is just an arrogant propagandistic nonsense and surely not a contribution to the scientific debate.

We may not be the most special creatures (and universe) in the multiverse (even though Leibniz used to say that our world/life is the best possible world/life) but we are not the most generic (or messy) ones, either. Both of these assumptions are irrational philosophical prejudices and unjustified extrapolations from cases where they happened to work. Now, we can pretty much sit at a reasonably generic point of a statistical distribution but you can't ever be sure how close to the central or most likely values you are. For different quantities, the distance from the "genericity" may be very different. There is clearly no universal answer.

Sometimes you are very generic, and then the insight about your genericity is not too interesting because it carries low information. Sometimes you are special. The information clarifying why you are so special is higher (if a theory predicts a very special feature, it is very predictive) but such cases are less likely. There is a trade-off going on here and whoever thinks that the very anthropic assumptions can lead to a high-information conclusion that is nevertheless very likely to be true, without finding non-anthropic arguments and mechanisms, is clearly making a logical error.

There is no rational reason to think that individual vacua should carry the same "weight" in the anthropic distribution. And if you use the very existence of life to deduce something about the low-energy parameters, you won't get too much interesting information because we know much more than the fact that life exists in our Universe. We also know the values of all low-energy parameters that make this life (and many other things) possible. Anything that can be derived about our compactification from the existence of life can clearly be derived from the known values of the parameters, too (because the life itself can be derived from them). Physicists should finally appreciate that it is legal for them to use all the known experimental data (including those found in the near future) in their search for the correct theory (and its vacuum). It used to be legal in the past, too. ;-)

Why would you ever use the incomplete information about the existence of life only rather than the full information you can have? It looks like a children's game where a kid has to determine something without looking somewhere. But scientists are allowed to look, aren't they? Note that it is still the same complaint against the "selection fallacy" that I have already raised many times. When the anthropic people calculated a probability as "N times P" (Schellekens in his point (3)), they were also using an incomplete information, representing every vacuum by a "generic representative" for some class even though more accurate calculations are clearly possible as long as people keep on improving and sharpening their knowledge about particular vacua and abilities to deal with them.

Laws that maximize life naturally

Finally, I want to say that the ultimate laws governing the vacuum selection can be "naturally" compatible with the existence of life in the preferred Universes.

A universe that admits life has to satisfy all kinds of features and many of them have a quantitative character: various parameters and ratios have to be small. You have to have a lot of hierarchies of scales (a small cosmological constant, an electroweak-Planck gap, fermionic mass hierarchies), a lot of different long-lived states (nuclei, molecules) in the spectrum that have sufficiently different geometries, and so on. Imagine that you create a similar "index of life magic" I_{LM} as a function of various "healthy gaps" in such a way that the vacua with a higher value of the index can reasonably be expected to admit life "more easily" than the vacua with a low value of the index.

This index is an artificial human invention but it is completely plausible that there exists a natural formula - e.g. one derivable from a generalization of a Hartle-Hawking wave function - that has similar consequences and that naturally makes it more likely for life to appear in the universe that is also predicted to be more likely by a cosmological HH-like selection formula.

Do you think that such a hypothesis is a form of a conspiracy theory? Feel free to believe it is. But the objects that make life extremely unlikely in certain environments are just continuous numbers: discrete conditions only reduce the number of viable vacua by a factor comparable to one (such as two). And continuous numbers often like to enter formulae. When you have a Hartle-Hawking formula dictating the probability of different vacua (or low-energy parameters) after an early era of cosmology, it usually depends on these numbers: recall the dependence on the cosmological constant (with the problematic sign). The dependence can be strong, it is almost guaranteed that there is a bias, and the probability that the bias is in the direction that favors the "viable" vacua is significant, maybe even higher than 50% (a priori). When you actually fill in the details of this theory, you will be able to say that the probability is 100%. ;-)

If this picture is correct, there can exist an old-fashioned scientific, non-anthropic explanation why we live in a universe where life looks a priori easy. I find this picture speculative but from the viewpoint of eternity, it is very plausible. Viability can be imprinted to our world through the basic laws of early cosmology. Every "theorem" that tried to prove that similar calculations must be impossible has been circular so far: all of them had to assume that our Universe belongs to the gray zone and it has no theoretical or phenomenological "fingerprints" or special features that could identify it - and they proudly proved that one can't ever identify such a vacuum by its fingerprints in a polynomial time (sorry, Frederik and Michael, but that's what you're doing).

I wouldn't make a bet that someone will actually find such a non-anthropic explanation of the viability of our Universe in a few years but many key events in the history of science have been unexpected. Moreover, the belief that the anthropic fog won't be falsified in a near future (a belief I share) is something different than a belief that it is the correct answer (which I don't share). People naturally focus on research directions where they can make progress, so I am certainly not afraid that every talented physicist is going to work on a hopeless project. But even if some project loses man-hours, it doesn't mean that there can't ever be a new breakthrough in this project. But even if you don't believe that such new insights about the vacuum selection problem will be found in the future, it is probably more fruitful for the physicists to focus on attempts to find new patterns and laws rather than self-fulfilling attempts to prove that science is over. ;-)

Because the arguments that our Universe must be generic (and there is no extra information we can ever learn about it) seem to be circular and seem to contradict the whole history of science which has always seen some additional progress, I think it is reasonable for a physicist to expect that every "generic" description of a system we don't understand is a temporary state of affairs. The more we will know, the more the fuzzy anthropic fog is going to be replaced by a sharper picture full of fascinating insights, important patterns, illuminating relationships, exact numbers, and specific links to previous theories as well as observations, insights that are similar to hundreds of those that have already been found.

And that's the memo.

Funny stuff from McSweeney's:

General relativity is your high-school girlfriend all grown up. Man, she is amazing. You sort of regret not keeping in touch. She hates quantum mechanics for obscure reasons.

Cosmology is the girl that doesn't really date, but has lots of hot friends. Some people date cosmology just to hang out with her friends.

Can we come up with a similar list for the brain sciences? I think you could replace quantum mechanics with brain imaging and perhaps substitute electrophysiology for general relativity.

Via kottke

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We can't joke around too much about this Hurricane Dolly, I'm afraid. The weather is not terrible here in Corpus, but conditions are rapidly deteriorating in Brownsville. We now have reports of tornado warnings in nearby counties, and confirmed power outages for more than 9000 people.

News reports are forecasting an incredible amount of rain (up to 15 inches). If i remember right, that would be the equivalent of a 5 foot snowstorm in the Northeast.

From the Associated Press:

Dolly, upgraded from a tropical storm Tuesday, had sustained winds of 95 mph, just short of becoming a Category 2 storm. At 9 a.m. EDT Wednesday, the storm's center was about 40 miles east of Brownsville, moving northwest at about 8 mph.

A hurricane warning was in effect for the coast of Texas from Brownsville to Corpus Christi and in Mexico from Rio San Fernando northward.

Utility company AEP Texas reported power outages to more than 9,200 customers in Cameron County.

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Physicists love spontaneous symmetry breaking. It’s a great way to reconcile the messiness of reality with our belief in simple and beautiful underlying mechanisms. We posit that the true fundamental dynamics of the world has some symmetry — X can be exchanged with Y, and all relevant processes are unchanged — but the actual state of the world does not respect that symmetry, which leaves it hidden (or “nonlinearly realized,” if you want to sound all sciencey). Deep down, a (left-handed) electron is completely interchangeable with an electron neutrino; but in the world as we find it, this symmetry is broken, and we end up with an electron that is charged and massive, a neutrino that is neutral and nearly massless. The Higgs boson that the Large Hadron Collider is looking for would be the telltale sign of the mechanism behind this symmetry breaking.

For reasons which escape me, this concept has not been borrowed (as far as I can tell) by social scientists and pundits more generally.* Which is too bad, as it explains a great deal. For example, appealing to the concept of spontaneous symmetry breaking would have been really helpful to Whoopi Goldberg on The View recently, as she patiently tried to explain to a distraught Elisabeth Hasselbeck why it’s just not the same when black people use the word “nigger” as when white people do. (From Sociological Images, via The Edge of the American West.)

Which is not to say that it’s always okay, or that there is no thoughtful critique of the re-appropriation of derogatory language by targeted groups, etc. Just that “If it’s wrong when white people say it, it should be wrong when black people say it too! It’s just not fair!” is far too simple-minded to carry any water.

Let’s imagine that, in our view of a happy future utopia, all races find themselves in situations of perfect equality of opportunity and dignity. Everyone enters society with equal status, and people are judged not by the color of their skin but by the content of their character. (The “symmetric vacuum.”) In such a world, arguments like “If you can do it, why shouldn’t I be able to?” would carry some weight. But even if we want that to be the world — even if we believe that the grand unified theory of social ethics involves a symmetry of rights and obligations under the interchange of various racial categories — it’s not the world in which we live. In the real world, different races don’t go through life with the same masses and charges (if you will). There really is such a thing as discrimination, legacies of poverty and exclusion, and so on. We can argue about the best way to deal with those features of reality, but pretending that they don’t exist isn’t a very useful strategy.

As Whoopi explains, many blacks have chosen to re-appropriate the n-word as part of a conscious strategy of fighting back against a power dynamic that uses language to keep them at the bottom. Again, one can argue about the effectiveness of that strategy, and the circumstances under which it is appropriate, and whether Jesse Jackson should really have used that term in referring to Barack Obama. But it doesn’t follow that “if it’s fair for you, it should be fair for me.” Here is a guy who sadly doesn’t get it; a white high-school teacher who is genuinely puzzled about why he got in trouble for calling one of his black students “nigga.”

I was contemplating writing this post for a long time, with the relevant symmetry being men/women and the social milieu being the scientific community. Too many physicists reason along the following lines: “Men and women should be treated equally. Therefore, any time we privilege one over the other, as in making a special effort to encourage women in science, we are making a mistake.” That would be a reasonable argument, if the symmetry weren’t dramatically broken by the state in which we find ourselves. Which happily is not a stable vacuum! (Note that the underlying assumption is not that different genders or races are necessarily equivalent when it comes to innate abilities; that is largely beside the point, and obsession about those questions gets to be a little creepy. But they should certainly have equal opportunities — and right now, they don’t.) Treating one group differently than the other isn’t what we ultimately want to be doing — it’s not part of the happy utopia — but it might be the best response to the current state of unequal treatment overall.

But Whoopi’s little teaching moment was too good to pass up. If the discussion of race and gender in the rest of the MSM rose to that level of sophistication, we’d all be better off.

———-

*I’ve been searching for an excuse to mention Kieran Healy’s Standard Model of Sociophysics. I’m not sure if this is it, but I’ll take it.

In "week267" see the tilings of the Alhambra and learn about wallpaper groups, 17 wallpaper groups, their corresponding 2d orbifolds, the role of 2-groups as symmetries of orbifolds, the work of Carrasco and Cegarra on hypercrossed complexes, and the work of João Faria Martins on the fundamental 2-group of a 2-knot. john http://math.ucr.edu/home/baez/ baez@math.ucr.edu

(See also Anthony Watts' comments.)

I think his testimony was extremely good. You can see the anonymous faces around who don't want to hear any rational things about the climate, its sensitivity, the natural effects, and the sensible strategies to organize the scientific research in order to find the correct and important insights about the climate.

When Spencer was finished, the only thing that Barbara Boxer was able to say was to congratulate that Spencer was jokingly named Rush Limbaugh's official climatologist. She just wanted to "point it out for people to understand". She apparently thinks that this comment should settle the debate. Well, among the idiots who vote for her, it probably does.



I have great news for you, Ms Boxer. You have been named the official clown of Rush Limbaugh's show which is a higher rank than the official climatologist. Congratulations! I hope that the next time, you won't be hiding your own title, either.

150 minutes of video

A more complete video from the hearings is here. At the beginning, Boxer enumerates millions of catastrophes that are caused by warming, an effect that hasn't existed at least for ten years. As her following comments reveal, her support for this fashionable nonsense is clearly motivated by her desire to spit on Bush's administration. Mr Lautenberg blames global warming and George Bush for a disease of his grandkid: quite incredible. Testimonies and questions follow. You may also go to 1:01:40 where Frank Trautenberg or Lautenberg or what is the name of the old man (D - New Jersey) asks some questions to Spencer.

I must say that these arrogant political fools drive me up the wall and I must pause the video every 10 seconds to avoid overdosing. They don't know 1% of Spencer's knowledge about the climate but they still indicate that they don't have to listen.

Spencer says a lot of key things, for example that the humans obviously have some impact on the climate - for example, they influence the area of forests - which doesn't mean that they can stop using fossil fuels. Whether the carbon technologies can be replaced by something else in the future will depend on technological breakthroughs and you can't legislate new technologies into the existence. In fact, billions have already been spent and nothing that could be called a breakthrough has emerged.

But those political faces simply don't want to hear anything that makes sense. Instead, they want to tell Spencer and real scientists in general that they are putting children at risk. And they want to listen to bought scientists such as Kevin Trenberth to say things that the politicians pay them for saying. In his speech, Spencer recalls that Robert Watson, the 1997-2002 chairman of the IPCC, told Spencer 20 years ago that CO2 should be regulated (much like freons), years before a scientific "justification" was on the table.

It's a very sad tragicomedy - a great example how the active morons such as Boxer and Lautenberg "naturally" get to the top of political affairs in every country that suddenly allows its government to decide about things that should only be decided by the free individuals. At this point, science is completely irrelevant. Science was only good in its manipulated, corrupt form to help the morons to get to their chairs and gain the power.

Frankly speaking, I found even comments by some Republicans, such as Larry Craig (around 56:00), who is a semi-skeptic, insulting, e.g. when he called Spencer "outsider" in the climate science. What the [intercourse] does it mean? By all objective criteria, Spencer is an achieved scientist at the center of his discipline.

Incidentally, Antarctica was about 17 °C warmer 14 million years ago than it is today: ostracods have spoken.

Gina Trapani, having found herself marinated in studies about productivity and the internet, muses (in Lifehacker) on what it all means:

Every time a new research study around personal productivity and office culture appears, we dutifully post the “proof” that information overload, email distractions, and multitasking are keeping you from getting work done—but are they? Sure, many of these findings seem very feasible, but it’s hard not to think they’re published only as a crutch for a larger commercial or media message—either “the internet is destroying your life!” or “you need to buy this product.” …

Even though we’re very much a cog in this giant machine, I have my doubts.

The longer I do this, the more I suspect that a good part of the “information overload” story is a myth cooked up by folks who don’t know how to use the internet well in order to demonize something they don’t understand. I get more done via email and surfing the web than my parents ever did using phones and libraries, even when I’m having a bad day and switch to my email application the moment I see a new message notification.

There's a classic paper on the Quantum Zeno Effect that I discuss in Chapter 5 of the book. The paper does two tests of the effect, and presents the results in two bar graphs. They also provide the data in tabular form.

My question is this:

If I copy the data from the table, and make my own version of the graph, am I obliged to contact them and ask permission to duplicate their results in my book?

If I were copying their graphs directly, I would definitely contact them and ask permission, but I'm not as certain about using their data to make my own version of their graphs.

Complicating matters, when I asked Kate about this, she replied "Why would you need to ask permission to reproduce figures? Isn't that fair use?" I have no idea why it is, I just know that it's What Is Done in these cases (having been contacted a few times for permission to reproduce stuff from papers I wrote).

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Followup to:  Should We Ban Physics?

It may come as a surprise to some readers of this blog, that I do not always advocate using probabilities.

Or rather, I don't always advocate that human beings, trying to solve their problems, should try to make up probabilities, and then apply the laws of probability theory or decision theory to whatever they just made up, and then use the result as their final belief or decision.

The laws of probability are laws, not suggestions, but often the true Law is too difficult for us humans to compute.  If P != NP and the universe has no source of exponential computing power, then there are evidential updates too difficult for even a superintelligence to compute - even though the probabilities would be quite well-defined, if we could afford to calculate them.

So sometimes you don't apply probability theory.  Especially if you're human, and your brain has evolved with all sorts of useful algorithms for uncertain reasoning, that don't involve verbal probability assignments.

Not sure where a flying ball will land?  I don't advise trying to formulate a probability distribution over its landing spots, performing deliberate Bayesian updates on your glances at the ball, and calculating the expected utility of all possible strings of motor instructions to your muscles.

Trying to catch a flying ball, you're probably better off with your brain's built-in mechanisms, then using deliberative verbal reasoning to invent or manipulate probabilities.

But this doesn't mean you're going beyond probability theory or above probability theory.

The Dutch Book arguments still apply.  If I offer you a choice of gambles ($10,000 if the ball lands in this square, versus $10,000 if I roll a die and it comes up 6), and you answer in a way that does not allow consistent probabilities to be assigned, then you will accept combinations of gambles that are certain losses, or reject gambles that are certain gains...

Which still doesn't mean that you should try to use deliberative verbal reasoning.  I would expect that for professional baseball players, at least, it's more important to catch the ball than to assign consistent probabilities.  Indeed, if you tried to make up probabilities, the verbal probabilities might not even be very good ones, compared to some gut-level feeling - some wordless representation of uncertainty in the back of your mind.

There is nothing privileged about uncertainty that is expressed in words, unless the verbal parts of your brain do, in fact, happen to work better on the problem.

And while accurate maps of the same territory will necessarily be consistent among themselves, not all consistent maps are accurate.  It is more important to be accurate than to be consistent, and more important to catch the ball than to be consistent.

In fact, I generally advise against making up probabilities, unless it seems like you have some decent basis for them.  This only fools you into believing that you are more Bayesian than you actually are.

To be specific, I would advise, in most cases, against using non-numerical procedures to create what appear to be numerical probabilities.  Numbers should come from numbers.

Now there are benefits from trying to translate your gut feelings of uncertainty into verbal probabilities.  It may help you spot problems like the conjunction fallacy.  It may help you spot internal inconsistencies - though it may not show you any way to remedy them.

But you shouldn't go around thinking that, if you translate your gut feeling into "one in a thousand", then, on occasions when you emit these verbal words, the corresponding event will happen around one in a thousand times.  Your brain is not so well-calibrated.  If instead you do something nonverbal with your gut feeling of uncertainty, you may be better off, because at least you'll be using the gut feeling the way it was meant to be used.

This specific topic came up recently in the context of the Large Hadron Collider, and an argument given at the Global Catastrophic Risks conference:

That we couldn't be sure that there was no error in the papers which showed from multiple angles that the LHC couldn't possibly destroy the world.  And moreover, the theory used in the papers might be wrong.  And in either case, there was still a chance the LHC could destroy the world.  And therefore, it ought not to be turned on.

Now if the argument had been given in just this way, I would not have objected to its epistemology.

But the speaker actually purported to assign a probability of at least 1 in 1000 that the theory, model, or calculations in the LHC paper were wrong; and a probability of at least 1 in 1000 that, if the theory or model or calculations were wrong, the LHC would destroy the world.

After all, it's surely not so improbable that future generations will reject the theory used in the LHC paper, or reject the model, or maybe just find an error.  And if the LHC paper is wrong, then who knows what might happen as a result?

So that is an argument - but to assign numbers to it?

I object to the air of authority given these numbers pulled out of thin air.  I generally feel that if you can't use probabilistic tools to shape your feelings of uncertainty, you ought not to dignify them by calling them probabilities.

The alternative I would propose, in this particular case, is to debate the general rule of banning physics experiments because you cannot be absolutely certain of the arguments that say they are safe.

I hold that if you phrase it this way, then your mind, by considering frequencies of events, is likely to bring in more consequences of the decision, and remember more relevant historical cases.

If you debate just the one case of the LHC, and assign specific probabilities, it (1) gives very shaky reasoning an undue air of authority, (2) obscures the general consequences of applying similar rules, and even (3) creates the illusion that we might come to a different decision if someone else published a new physics paper that decreased the probabilities.

The authors at the Global Catastrophic Risk conference seemed to be suggesting that we could just do a bit more analysis of the LHC and then switch it on.  This struck me as the most disingenuous part of the argument.  Once you admit the argument "Maybe the analysis could be wrong, and who knows what happens then," there is no possible physics paper that can ever get rid of it.

No matter what other physics papers had been published previously, the authors would have used the same argument and made up the same numerical probabilities at the Global Catastrophic Risk conference.  I cannot be sure of this statement, of course, but it has a probability of 75%.

In general a rationalist tries to make their minds function at the best achievable power output; sometimes this involves talking about verbal probabilities, and sometimes it does not, but always the laws of probability theory govern.

If all you have is a gut feeling of uncertainty, then you should probably stick with those algorithms that make use of gut feelings of uncertainty, because your built-in algorithms may do better than your clumsy attempts to put things into words.

Now it may be that by reasoning thusly, I may find myself inconsistent.  For example, I would be substantially more alarmed about a lottery device with a well-defined chance of 1 in 1,000,000 of destroying the world, than I am about the Large Hadron Collider switched on.  If I could prevent only one of these events, I would prevent the lottery.

On the other hand, if you asked me whether I could make one million statements of authority equal to "The Large Hadron Collider will not destroy the world", and be wrong, on average, around once, then I would have to say no.

What should I do about this inconsistency?  I'm not sure, but I'm certainly not going to wave a magic wand to make it go away.  That's like finding an inconsistency in a pair of maps you own, and quickly scribbling some alterations to make sure they're consistent.

I would also, by the way, be substantially more worried about a lottery device with a 1 in 1,000,000,000 chance of destroying the world, than a device which destroyed the world if the Judeo-Christian God existed.  But I would not suppose that I could make one billion statements, one after the other, fully independent and equally fraught as "There is no God", and be wrong on average around once.

I can't say I'm happy with this state of epistemic affairs, but I'm not going to modify it until I can see myself moving in the direction of greater accuracy and real-world effectiveness, not just moving in the direction of greater self-consistency.  The goal is to win, after all.  If I make up a probability that is not shaped by probabilistic tools, if I make up a number that is not created by numerical methods, then maybe I am just defeating my built-in algorithms that would do better by reasoning in their native modes of uncertainty.

Of course this is not a license to ignore probabilities that are well-founded.  Any numerical founding at all is likely to be better than a vague feeling of uncertainty; humans are terrible statisticians.  But pulling a number entirely out of your butt, that is, using a non-numerical procedure to produce a number, is nearly no foundation at all; and in that case you probably are better off sticking with the vague feelings of uncertainty.

Which is why my Overcoming Bias posts generally use words like "maybe" and "probably" and "surely" instead of assigning made-up numerical probabilities like "40%" and "70%" and "95%".  Think of how silly that would look.  I think it actually would be silly; I think I would do worse thereby.

I am not the kind of straw Bayesian who says that you should make up probabilities to avoid being subject to Dutch Books.  I am the sort of Bayesian who says that in practice, humans end up subject to Dutch Books because they aren't powerful enough to avoid them; and moreover it's more important to catch the ball than to avoid Dutch Books.  The math is like underlying physics, inescapably governing, but too expensive to calculate.  Nor is there any point in a ritual of cognition which mimics the surface forms of the math, but fails to produce systematically better decision-making.  That would be a lost purpose; this is not the true art of living under the law.

Bad news often has self-fulfilling prophesy effects.  Tell a student his work is bad and he might give up.  Telling friends someone is unpopular makes her even less popular.  Tell a sport team they will lose and they might not try as hard.  Tell customers a product is bad and they might look at it more carefully for flaws or switch products, and with fewer customers the producer has fewer resources to improve the product.  Tell people a bank is in trouble and they withdraw their deposits, stressing the bank further.

But most of us think it crazy to therefore ban bad news.  Sure some might maliciously spread negative rumors to hurt a rival, but this hardly means we should forbid anyone from ever talking negatively about anything!  We should instead rely on listeners treating rumors skeptically and listening less to those they find to be unreliable sources.

Alas, all this common sense goes out the window when bad news comes via financial markets.  When we buy stock observers reasonably interpret that as our saying we have good news about that stock, while selling is reasonably interpreted as bad news.   And so the US SEC is doing more to ban bad news: 

An order from the Securities and Exchange Commission aimed at protecting some of the country's largest financial companies against a form of short selling took effect yesterday. .... In the current financial environment, short selling can be especially harmful to banks and brokerage firms because customers and investors may view sinking stock prices as a sign of trouble and react by withdrawing deposits.

The result of these sort of policies is sad and obvious:  it will take longer for us to find out about bad news, and so we will interpret silence and apparent good news more skeptically.  That is, we will just know less.  Note also that speculative markets actually do better at punishing malicious rival rumors -- those who spread false rumors via gossip are less reliably punished than those who sell short a stock they know to be valuable.

Coming soon after speculators were blamed for rising commodity prices, I fear this is bad news for hopes for legal prediction markets anytime soon. 

Girard on categories david http://www.dcorfield.pwp.blueyonder.co.uk/ david.corfield@tuebingen.mpg.de

I am liveblogging Hurricane Dolly from Corpus Christi, Texas. It's raining here in the Coastal Bend. Not too much wind. Thanks to the storm we have a "snow day" at school. Plus, I don't have to water the lawn for a week. Things are looking up, but flooding is forecast for the region, so there could still be trouble.

My wife brought a camera to the supermarket last night to document the supermarket's reaction to the storm here in South Texas. We expected large pallets of drinking water, but there's no evidence of profiteering. Rather, it seems there was a run on sliced bread and tuna fish. Other people must have come to the same conclusion we did. Tuna fish sandwiches are good hurricane food.

So, now I'm wondering "what happens if global warming leads to more hurricanes, and therefore more tuna fish consumption". That could be troubling.

The idea worries me partly because Chris Mooney is worried. Storm pundits are under the impression that global warming stokes hurricanes. Where hurricanes make landfall, tuna disappears off the shelves. Here lies the problem, and its hypothesis.

In the cities where canned tuna is tested, mercury levels are above the recommended dose for daily consumption. Daily intake of canned tuna may result in what's been referred to as a "fish fog". Through inference I will hazard that most canned tuna is above recommended levels of mercury. Therefore, an upward trend in sea surface temperatures could elevate local mercury intake and subsequently "stupidize" our population.

Consider a positive feedback loop wherein the global warming comedy "Sizzle" comes to play in a theater in Corpus Christi and "people just don't get it" because folks have been eating too much tuna. The policy ramifications are enormous, like more seawalls in the face of rising seas. I should be worried. I know.

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A lot of reactions with nucleophiles' rates are determined by how good a leaving group you have. For leaving group reasons and others, DMAP is a great organocatalyst:

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Stephen Gisselbrecht has joined the Luxuriant Flowing Hair Club for Scientists. He says:

I am happy to have found a scientific society that will cater to more than one of my interests.

Stephen S. Gisselbrecht, MA, LFHCfS
Senior Technical Research Assistant
Division of Genetics, Department of Medicine
Brigham and Women’s Hospital
Boston, Massachusetts, USA

Newsflash! This just in from the Weather Channel:

Dolly has strengthened to become the second hurricane of the 2008 Atlantic hurricane season. It has maximum sustained winds of 75 mph; a category one hurricane.

Hurricane Dolly may continue to strengthen tonight and tomorrow morning before landfall. It is expected to make landfall along the northern Mexico or southern Texas Gulf Coast by Wednesday morning or during the midday hours.

Join me for a warm cup of coffee as I evaluate local conditions, and decide whether or not its safe for my family to leave the house tomorrow morning. To go puddle jumping, ... for example.

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Clouds can be a sailor's best friend. Given, you'd have to be an awfully lonely sailor, and probably have to scratch a half dozen unmentionables off the list before you ever got to "clouds", but, ... hey, some modern sailors keep a nice cloud book with them in the navigation room. OK? It helps to whiddle away the hours on a quiet sea spent waiting for the research submersible team to break the surface. Really. Ask anybody.

Anyways, in anticipation of the approaching Tropical Storm Dolly, I trekked down to Corpus Christi Bay around 2pm to see how the cloud cover had changed with the impending storm. When I moved here to Corpus Christi one of the things that impressed me most was the beautiful cloudy skies. That and a two bedroom home for less than 200k. I moved here from LA, where these prices are no longer possible.

The images above show a view of the Bay from a few blocks down my street, and another one downtown. White puffy cumulus clouds lie off to the east over Mustang Island in photos 1 and 2, above. The vertical development indicates warm (darn hot, actually) air rising towards cooler air, where it condenses. Cumulus clouds are associated with good weather. The clouds often associated with the bad weather are below the fold.

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BrianR at Clastic Detritus brought my attention to a new wonderful bathymetric map of the globe. Despite his questionable loyalty to volcanoes, Brian knows a good map when he sees one and I agree that this one is indeed beautiful. GEBCO (General Bathymetric Chart of the Oceans) is an initiative joining the Intergovernmental Oceanographic Commission and International Hydrographic Organization. You can get the high res version of the above here. Read the comments on this post...

This storm, heading for the Mexico-Texas border, is now a hurricane. Our second of the 2008 season, and it's not even August yet....

Eric Berger has some interesting discussion of just how busy this year is starting out. Only three years in recorded history have been busier so early, and two of them are the busiest two years in history: 2005 and 1933.

Did I mention I was worried?

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Where the Hell is Matt? (2008) from Matthew Harding on Vimeo.

Source

[Hat tip: Bunny]

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Maria over at Green Gabbro feels that I have printed a false and malicious post for the purpose of defaming volcanoes. I cannot be held liable if the accusations are true. Maria thinks that printing a list of "all the good things volcanoes do" will be more than sufficient to make up for their previous indiscretions. But perhaps we need a bit of perspective on the role of volcanoes in the history of life.

According toWignall's excellent review in 2001 on why and how volcanoes are evil, 6 of the 15 major extinctions in the history of life coincide with major episodes of volcanicity. In the last 300 Ma, all extinctions coincide with large igneous deposits.

How did volcanoes do it? Wignall provides this wonderful diagram (click for larger) based on the chain of events occurring in conjunction with the Siberian Traps (a large eruption event ~250Mya).

Of course some of Maria's list is also suspect.

1. Volcanoes also flux out CO2, which keeps us warm and cozy. Or they cause considerable global warming which leads to oceanic stagnation and marine anoxia that ultimately kills everything. But let's not dwell on the negatives.


2. Ditto other volatiles. Do you want to try life without volcanic sulfur? I don't either.Sure sulfur can come from volcanoes. But anaerobic bacteria can produce the same from sulfate minerals. These deposits are so large they are good enough for commercial sulfur production in US, Poland, Russia, Turkmenistan, and the Ukraine. I'm no geologist but I am also pretty sure that sulfate, the major form of sulfur in the oceans, can also come from the weathering of continental rocks.


3. Volcanoes created the continents (and islands). Without continents, there would be no primeval life-cradling tide pools. Also, we would be mermaids.With no volcanoes the whole world would be an ocean. Sounds good to me! What makes you think the primordial ooze was so close to land?


4. Submarine volcanoes provide a source of energy for all manner of exotic salty friends.Sure there a few hydrothermal vent organisms scatter along the ocean bottom. But there are far more who don't need the vents. Helping a few species will not mitigate killing off millions!

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