For my May 2007 diary, go here.

Diary - June 2007

John Baez

June 1, 2007

I've been fond of Andalusia for quite a while now, without ever having been there. So, I was really excited when Lisa finally showed me the pictures she took at the Alhambra when she visited Granada in May.

Here's one taken from a parapet looking down into the town, and one of a pool:

Here's a bath inside the Alhambra:

But the best part is all the tilework inside! A tiny taste:

June 7, 2007

It's the last day of class! Yay!

I learned a lot from teaching undergraduate number theory — for example, I learned how Gauss and Eisenstein proved quadratic reciprocity in a tour de force of elementary methods. I also made some progress in understanding how cohomology theory infiltrates physics and computation in my seminars on Quantization and Cohomology and Cohomology and Quantization. I didn't do a great job on my undergraduate differential equations course — I've taught that a bunch of times, and I was just too busy to do anything different this time.

The quarter was quite exhausting. My number theory class was at 8 am, directly followed by the differential equations class. I prepared for these classes while falling asleep the night before. Then I'd pop up at 6:30 am, make coffee, prepare some more, make breakfast, and charge out the door at 7:30.

In fact I tried to prepare for classes ahead of time, on Mondays. But, as the quarter ran on and I wore out, I'd sometimes slack off, leaving more work to the last minute.

It's interesting how much of what we accomplish in life is limited only by our "energy". This "energy" is a mysterious but crucial biological-spiritual commodity. It's not the same as the physicist's concept of energy.

It seems to come in different forms: joie de vivre, élan vital, gumption, zest, vigor, pep, spirit and chi. I wonder how scientifically it's been studied.

We can set up a plan of action and then, after carrying it out successfully for a month or two, simply "run out of energy" and let it collapse. Carrying out a plan takes energy. A spontaneous approach often helps us build up more energy. That's called "following the tao". But sometimes it seems there's a need to plan.

Perhaps you're wondering why I'm saying such obvious stuff! It's because people sometimes marvel at my inexaustible energy. It doesn't seem special to me... until I run out, like this spring.

June 11, 2007

Lisa went to Hong Kong today; we'll hook up again after I come back from visiting my parents in DC.

June 15, 2007

My grad students Derek and Jeff handed in their theses! We're all very glad this is done. They were working hard to the very last minute. Not very good planning — and indeed, this contributed to my burnout this spring. But they did a lot of interesting, substantial work.

I'm dying to tell the world about it! I'll give a talk about Derek's thesis at the Astroparticule et Cosmologie group in Paris Université 7 pretty soon. I'll find some other venue to talk about Jeff's.

June 16, 2007

Chris and Menakshee visited. Among many other things, they told me about this book: It's about voodoo and zombies in Haiti. Its conclusions are remarkable and controversial. Quoting a Wikipedia article:
Wade Davis, a Canadian ethnobotanist, presented a pharmacological case for zombies in two books, The Serpent and the Rainbow (1985) and Passage of Darkness: The Ethnobiology of the Haitian Zombie (1988). Davis traveled to Haiti in 1982 and, as a result of his investigations, claimed that a living person can be turned into a zombie by two special powders being entered into the blood stream (usually via a wound). The first, coup de poudre (French: 'powder strike'), induced a 'death-like' state because of tetrodotoxin (TTX), its key ingredient. Tetrodotoxin is the same lethal toxin found in the Japanese delicacy fugu, or pufferfish. At near-lethal doses (LD50= 5-8μg/kg), it can leave a person in a state of near-death for several days, while the person continues to be conscious. The second powder, composed of dissociatives like datura, put the person in a zombie-like state where they seem to have no will of their own. Davis also popularized the story of Clairvius Narcisse, who was claimed to have succumbed to this practice. There remains considerable skepticism about Davis's claims, and opinions remain divided as to the veracity of his work, although there is wide recognition among the Haitian people of the existence of the "zombi drug". The vodoun religion being somewhat secretive in its practices and codes, it can be very difficult for a foreign scientist to validate or invalidate such claims.

June 18, 2007

Today Derek Wise graduated and I "hooded" him — a medieval ritual, with everyone dressed in academic regalia. Here I am in the academic procession:

When Derek's name was called we walked onto the stage and then he handed me the so-called "hood" (actually a sash-like thing), turned around, and bent down a bit. I put it over his head and tried to make sure it hung correctly from his neck. Then he walked down the aisle to get his picture taken with the chancellor of the university, Frances Cordova:

Clearly more knowledgeable than I, she adjusted his hood a bit before the shot. 151 graduate students went through the same ceremony that night.

Derek did this because his whole family came to see him graduate. The night before they even threw a surprise party for him! It was the first surprise party I'd ever attended — to me they're mainly events that happen in TV sitcoms. Derek had been told it was a meeting of his church group... which it was, but he wasn't told it was a party. Just as in the sitcoms, he got a headache right before the party and didn't want to go. His wife Sylena somehow managed to persuade him without giving away the secret.

My other student graduating this year, Jeffrey Morton, did not go to graduation ceremony. He came to the party, though. So did Danny Stevenson and his wife — Danny has been a visiting assistant professor at UCR for the last 3 years, working with me on things like nonabelian gerbes and 2-groups. He'll be taking off for Hamburg in the fall, to work with my pal Urs Schreiber.

So, there will be 3 fewer people around to work with next year. I'll miss them a lot. But, frankly, I look forward to a bit more peace and quiet — I hope it will help cure my overworked and harried mood.

Of course I'll keep working with all these folks. I plan to help Derek and Jeff chop their theses into publishable pieces and grow those pieces into perfect papers. I'm working with Danny on two papers right now, "A classifying space for nonabelian cohomology" and (joint with Alissa Crans and Urs Schreiber) "Canonical representations of 2-groups". But, I won't be having weekly meetings with them anymore. I'll still have weekly meetings with my grad students Alex Hoffnung, John Huerta, and Chris Walker, my former student Alissa Crans, and my longtime collaborator Jim Dolan. There's also a new grad student coming this fall who knows a lot of physics and wants to work with me, but maybe I'll let him wait a year before we get into weekly meetings.

I need to keep finding ways to stop spreading myself too thin. One possibility is to get all my grad students to attend a single joint meeting; this gives them less individual attention but gives them a chance to learn more stuff. Alex will be categorifying classical mechanics according to the strategy outlined in my course on quantization and cohomology. John will be working on the algebra of grand unified theories. Chris will be working on groupoidification, which will also be the topic of next year's seminar. Right now Alex and John have both been attending each other's meetings with me, but Chris (just getting started) has been separate. Is it too ambitious to insist that they all learn all of this stuff? Is it too ambitious for me to be thinking about all these things at once? Maybe I'd make faster progress, and feel happier, if I focused on fewer topics at a time... and get a bunch of grad students working on the same thing. For a long while I've been trying to broaden my scope, but maybe that's reached the point of diminishing returns.

I'll have to keep thinking about this stuff. My life is out of kilter, but I'm pretty good at solving problems when I tackle them head-on (I tell myself).

June 22, 2007

I'm visiting my parents.

On Tuesday the 19th I woke up at 3:45 am and got ready to fly to my parent's house — or more precisely, Dulles airport in northern Virginia. My shuttle was to pick me up at 5:30, but I just couldn't sleep thinking about all the little things I had to do. A lot of emails, since my folks are the only people in the Western hemisphere who are still without internet access. That's part of the charm of visiting them, actually, but it requires some pre-planning. Email Bob Coecke to tell him I probably couldn't come to Oxford this summer. Email Thomas Strobl to tell him the title of my talk in Vienna this summer: "Higher gauge theory and elliptic cohomology" — same talk as in Oslo, part of my new work-reduction strategy. Email Paul-André Mellies to ask him what to do when I show up in Paris. A few more emails while I'm at it...

Everything goes fine until I reach Denver; then a huge storm system on the east coast holds up our flight 3 hours, and our flight has to detour to work around the thunderstorms, so I show up at Dulles around 10:30 instead of 6:30.

In Denver I bought the new biography of Einstein, to keep myself entertained:

It's a good book — I recommend it. So, the delays were not an inconvenience.

I also did a little math, trying to understand my crazy idea, inspired by Garrett Lisi's work, of Cartan connections as having a "bosonic" and "fermionic" part. But I was too sleepy to go beyond some easy preliminary calculation. Clearly some new idea is needed to jump to the next stage, and for this — let me just remind myself, since I almost forgot — I should read those papers on analogies between general relativity and superfluid helium-3, where the metric tensor is built from two copies of a fermionic coframe field, just as a bosonic condensate is built from "Cooper pairs" of helium-3 atoms... or something like that. I'll download those papers when I return to civilization.

At Dulles my baggage failed to emerge from the maw of the machine, but not just mine: a woman asked me — twice, not instantly recognizing me the second time — whether the baggage from Denver was really showing up at this carousel, and eventually I started looking around, and then a nice guy said "Hey, our baggage is over here!" Someone had taken a bunch of it off the carousel and set it in some inconspicuous spot. I found my suitcase, and after a long wait caught a cab.

The cab driver didn't know Great Falls, so I had to guide him through the woods along dark and hilly roads towards my parents' house. He became increasingly fearful as he saw deer by the road — they can jump out and cause accidents. When we entered my parent's neighborhood, pitch-black except for the distant gleam of mansions here and there, he said "It's so dark here!" I replied "A lot of rich people live here — with horse barns and stuff." He said "Is that what rich people like? Living in the dark?"

(In case you're wondering, my parents are not rich. They just saved money and built a house way out in the woods.)

When we finally reached the gravel road my parents lived on, he practically moaned "Oh, this road is really bad!" I laughed and told him he could drop me off there. He obliged me apologetically, and drove off.

I hiked down the completely dark but perfectly familiar gravel road with my suitcase in hand, listening to the forest creatures. But then, I couldn't find my parents' driveway! It was embarrassing: I could see their house perfectly well, off in the distance, but it was so darn dark I couldn't spot the driveway. It felt like a dream: after a long flight with many delays, one winds up walking to ones parents house, lost in a spooky forest....

It reminded me of once when I went to a loop quantum gravity conference at the Albert Einstein Institute, maybe Loops '05. I took a train from Berlin to the small town of Golm, arriving late at night. I got off at the train station and suddenly realized how rural it was: no signs to the hotel, not many street signs, nobody to ask, just gravel roads trailing off into the darkness. Luckily I had a map, but it wasn't completely clear how to reach the hotel, so I had to hike around in the dark for quite a while before I figured it out. I sort of enjoy this kind of thing, as long as there's no real danger. It's also sort of scary. The well-lit grid of civilization slowly falls away, and you're out there alone in the night...

Anyway: I considered hiking straight through the woods to my parents' house, but I decided things were already interesting enough, so instead I called my mom and ask her to drive down the driveway a bit, just so I could see where it was. And so she did, and then it was obvious.

So, I got home shortly before midnight. A long and strange day. My dad was already in bed, but I said hi to him anyway.

Since then I've been talking to my parents, doing stuff with them, and working on a paper for the Mathematics and Narrative conference in Delphi this summer. I really like the title of this paper: "Why Mathematics is Boring". Unfortunately my file for this paper is called "boring.tex", which doesn't inspire me to work on it. But, I've finally gotten rolling on the project, and it's getting fun.

I should be working on it now. I'm sitting at my mom's desk looking out at the forest, listening to some music by Hossam Ramzy, The Best of Farid Al Atrash. Here's what I'm seeing:

This photograph doesn't really capture the beauty of the scene, since the camera saturates when the light gets too bright, showing white blobs where I see sunlit beech leaves with distinct veins, gently stirring in the breeze.

June 26, 2007

I got back home last night. Lisa got back from Hong Kong the previous day.

It's great to be back! We could have a lot of fun here this summer. It seems a bit unnecessary, and tiring, to zip off to Paris on the 30th. But, we've made our plans already, so off we'll go. It'll be fun.

I say "we've made our plans", but we're not sure yet whether we'll be staying on rue Lepic in Montmartre, or right near Luxembourg Garden. The latter seems a bit more convenient and nice.

June 27, 2007

Getting ready to go... it looks like we're staying near Luxembourg Garden, at 44 rue Monsieur le Prince. It's an apartment on the 4th floor, with no elevator and (possibly worse) no air conditioning. But, it's nicely located.

I got some interesting links from Andrew Stringer. His friend Dr. Jennifer McElwain at University College Dublin noticed that the pores in plant leaves — technically called "stomata" — tend to close when there's a lot of carbon dioxide in the atmosphere. She then studied fossil plant leaves and noticed that they had fewer stomata right around the end-Triassic and mid-Jurassic extinctions! This suggests that these mass extinctions were related to volcanic eruptions, which would emit large amounts of carbon dioxide and cause bursts of global warming.

Some references:

June 28, 2007

It's a bit embarrassing to get my news on biology from The Economist, but oh well... it's a good magazine. Seems there's been a paradigm shift in genetics when I wasn't looking. Junk DNA ain't "junk" anymore! A bunch of it codes for RNA molecules that shuttle about doing important jobs. I'll quote a little:
It is beginning to dawn on biologists that they may have got it wrong. Not completely wrong, but wrong enough to be embarrassing. For half a century their subject had been built around the relation between two sorts of chemical. Proteins, in the form of enzymes, hormones and so on, made things happen. DNA, in the form of genes, contained the instructions for making proteins. Other molecules were involved, of course. Sugars and fats were abundant (too abundant, in some people). And various vitamins and minerals made an appearance, as well. Oh, and there was also a curious chemical called RNA, which looked a bit like DNA but wasn't. It obediently carried genetic information from DNA in the nucleus to the places in the cell where proteins are made, rounded up the amino-acid units out of which those proteins are constructed, and was found in the protein factories themselves.

All that was worked out decades ago. Since then, RNA has been more or less neglected as a humble carrier of messages and fetcher of building materials. This account of the cell was so satisfying to biologists that few bothered to look beyond it. But they are looking now. For, suddenly, cells seem to be full of RNA doing who-knows-what.

And the diversity is staggering. There are scnRNAs, snRNAs and snoRNAs. There are rasiRNAs, tasiRNAs and nat-siRNAs. The piRNAs, which were discovered last summer, are abundant in developing sex cells. No male mammal, nor male fish, nor fly of either sex, would be fertile without them. Another RNA, called XIST, has the power to turn off an entire chromosome. It does so in females because they, unlike males, have two X chromosomes and would otherwise get an unhealthy double dose of many proteins. There is even a "pregnancy-induced non-coding RNA", cutely termed PINC. New RNAs are rushing forth from laboratories so rapidly that a group called the RNA Ontology Consortium has been promised half a million dollars to prune and tend the growing thicket of RNA-tailed acronyms.

In the light of this abundance, perceptions about what a gene is need to change. Genes were once thought of almost exclusively as repositories of information about how to build proteins. Now, they need to be seen for what they really are: RNA factories. Genes for proteins may even be in the minority. In a human, the number of different microRNAs, one of the commonest of the newly discovered sorts of RNA, may be as high as 37,000 according to Isidore Rigoutsos, IBM's genome-miner in chief. That compares with the 21,000 or so protein-encoding genes that people have.

Philosophers of science love this sort of thing. They refer to it as a paradigm shift. Living through such a shift is confusing for the scientists involved, and this one is no exception. But when it is over, it is likely to have changed people's views about how cells regulate themselves, how life becomes more complex, how certain mysterious diseases develop and even how the process of evolution operates. As a bonus, it also opens up avenues to develop new drugs.

The business about "it is beginning to dawn on biologists that they have got it wrong" sounds like journalistic exaggeration. If you click on some of the links you'll see that research on all these subjects is well underway. Indeed, the amount of work done so far is so vast it's scary! When you look at things like the National Center for Biomedical Ontology and the Gene Ontology Consortium — massive projects seeking to keep track of all the structures and concepts involved in various portions of biology — you get some sense of how huge a project we're undertaking: trying to completely understand life at the molecular level.

Our feeble brains are not enough to keep track of the complexity. We need all the help from computers we can get.

One big and rather simple question, though, is how much the central dogma of molecular biology will be called into question. This is the idea that information flows from DNA to the organism through expression of proteins but not back, except indirectly, via natural selection. Quoting some more of the Economist article:

Ronald Plasterk, of the University of Utrecht, in the Netherlands, suggests that microRNAs are important in the evolution of the human brain. In December's Nature Genetics, he compared the microRNAs encoded by chimpanzee and human genomes. About 8% of the microRNAs that are expressed in the human brain were unique to it, much more than chance and the evolutionary distance between chimps and people would predict.

Such observations suggest evolution is as much about changes in the genes for small RNAs as in the genes for proteins — and in complex creatures possibly more so. Indeed, some researchers go further. They suggest that RNA could itself provide an alternative evolutionary substrate. That is because RNA sometimes carries genetic information down the generations independently of DNA, by hitching a lift in the sex cells. Link this with the fact that the expression of RNA is, in certain circumstances, governed by environmental factors, and some very murky waters are stirred up.

It's evolutionary, my dear Watson

What is being proposed is the inheritance of characteristics acquired during an individual's lifetime, rather than as the result of chance mutations. This was first suggested by Jean Baptiste Lamarck, before Charles Darwin's idea of natural selection swept the board. However, even Darwin did not reject the idea that Lamarckian inheritance had some part to play, and it did not disappear as a serious idea until 20th-century genetic experiments failed to find evidence for it.

The wiggle room for the re-admission of Lamarck's ideas comes from the discovery that small RNAs are active in cells' nuclei as well as in their outer reaches. Greg Hannon, of the Cold Spring Harbor Laboratory in New York State, thinks that some of these RNA molecules are helping to direct subtle chemical modifications to DNA. Such modifications make it harder for a cell's code-reading machinery to get at the affected region of the genome. They thus change the effective composition of the genome in a way similar to mutation of the DNA itself (it is such mutations that are the raw material of natural selection). Indeed, they sometimes stimulate actual chemical changes in the DNA — in other words, real mutations.

Even this observation, interesting though it is, does not restore Lamarckism because such changes are not necessarily advantageous. But what Dr Hannon believes is that the changes in question sometimes happen in response to stimuli in the environment. The chances are that even this is still a random process, and that offspring born with such environmentally induced changes are no more likely to benefit than if those changes had been induced by a chemical or a dose of radiation. And yet, it is just possible Dr Hannon is on to something. The idea that the RNA operating system which is emerging into view can, as it were, re-write the DNA hard-drive in a predesigned way, is not completely ridiculous.

This could not result in genuine novelty. That must still come from natural selection. But it might optimise the next generation using the experience of the present one, even though the optimising software is the result of Darwinism. And if that turned out to be commonplace, it would be the paradigm shift to end them all.

(As Toby Bartels notes, what generates genuine novelty in the current Darwinian paradigm is not natural selection but mutation. Mutation generates novel organisms, and natural selection weeds out those that don't reproduce enough.)

For more, try this:

As if this weren't cool enough, my student Mike Stay (now working at Google) pointed out that Craig Venter's team has just succeeded in giving a bacterium a complete genome transplant: This is part of the quest for artificial life, which I discussed in my October 27, 2005 diary entry. The Craig Venter Institute has a Synthetic Biology group working on creating artificial life forms. Venter says they're close to synthesizing from scratch the entire genome of a small bacterium, Mycoplasma genitalium. If that genome could be put into a bacterium using the method announced today, Venter could claim he has made the first synthetic life form. Of course this is "cheating" in at least two senses: it uses an already functioning cell, and it uses the genome of an existing bacterium. The fun will start when they put in a novel, human-crafted genome.

June 29, 2007

I'm sure you've heard of the memo signed by Alberto Gonzales, now Attorney General of the United States, which claimed that the "new paradigm" of the war against terrorism "renders obsolete Geneva's strict limitations on questioning of enemy prisoners". And I'm sure you know what followed: torture at Abu Ghraib and elsewhere, a worldwide network of secret prisons, kidnappings at airports, and more.

You've probably also heard how the Bush administration began a massive program of secret wiretapping of US citizens, in direct contradiction to the Foreign Intelligence Surveillance Act.

And, more recently, you've probably heard how Dick Cheney claimed the office of the vice presidency was "not an entity within the executive branch" of the US government — and clearly not part of the legislative or judicial branches, either, hence exempt from regulations governing any branch of government!

I could list many more examples of how the Bush administration has flouted the Constitution, federal laws, and international treaties.

Ever wonder about just how this tide of lawlessness started, and who is behind it?

To a surprisingly large extent there's one man behind it: Dick Cheney. For the full story — or the little we know so far " read this:

It's gripping reading for anyone who cares about democracy, and how democracy can start to unravel thanks to the work of a ruthless and skillful man.

Here's a taste of his methods:

Stealth is among Cheney's most effective tools. Man-size Mosler safes, used elsewhere in government for classified secrets, store the workaday business of the office of the vice president. Even talking points for reporters are sometimes stamped "Treated As: Top Secret/SCI." Experts in and out of government said Cheney's office appears to have invented that designation, which alludes to "sensitive compartmented information," the most closely guarded category of government secrets. By adding the words "treated as," they said, Cheney seeks to protect unclassified work as though its disclosure would cause "exceptionally grave damage to national security."

A document from the Office of the Vice President is stamped "Treated as Secret/SCI"

Across the board, the vice president's office goes to unusual lengths to avoid transparency. Cheney declines to disclose the names or even the size of his staff, generally releases no public calendar and ordered the Secret Service to destroy his visitor logs. His general counsel has asserted that "the vice presidency is a unique office that is neither a part of the executive branch nor a part of the legislative branch," and is therefore exempt from rules governing either. Cheney is refusing to observe an executive order on the handling of national security secrets, and he proposed to abolish a federal office that insisted on auditing his compliance.

And, the truly scary thing is how he never gives up, even when he seems to be defeated:
Cheney and his allies, according to more than two dozen current and former officials, pioneered a novel distinction between forbidden "torture" and permitted use of "cruel, inhuman or degrading" methods of questioning. They did not originate every idea to rewrite or reinterpret the law, but fresh accounts from participants show that they translated muscular theories, from Yoo and others, into the operational language of government.

A backlash beginning in 2004, after reports of abuse leaked out of Iraq's Abu Ghraib prison and Guantanamo Bay, brought what appeared to be sharp reversals in courts and Congress — for Cheney's claims of executive supremacy and for his unyielding defense of what he called "robust interrogation."

But a more careful look at the results suggests that Cheney won far more than he lost. Many of the harsh measures he championed, and some of the broadest principles undergirding them, have survived intact but out of public view.

The vice president's unseen victories attest to traits that are often ascribed to him but are hard to demonstrate from the public record: thoroughgoing secrecy, persistence of focus, tactical flexibility in service of fixed aims and close knowledge of the power map of government. On critical decisions for more than six years, Cheney has often controlled the pivot points — tipping the outcome when he could, engineering stalemate when he could not and reopening debates that rivals thought were resolved.

June 30, 2007

I'm taking off for Paris today. I'm supposed to meet Paul-André at the Café Delmas, across from 2 Place de la Contrescarpe:

But before I go — some thoughts.

In her song "Same Time Tomorrow", Laurie Anderson asks:

And I what I really want to know is:
are things getting better, or are they getting worse?

It seems like an inane question, posed that way, without any qualifications. And indeed that's part of her point: we can't help wanting to know the answer to this question, even though it's unanswerably vague. I'm not sure what the point of this diary is, but sometimes it seems like an extended meditation on precisely this question.

That said, here's some evidence that things are getting better. (I've presented plenty for the opposite side.) Sometimes you get the impression that chronic ailments are getting more common as people live longer... but this book claims otherwise:

By their mid to late 60's, veterans from the US civil war (on the Union side) suffered from an average of 6 chronic conditions. For 65-year old American whites today, the number is 2.

There's a lot more here to remind us how things have been getting better. Of American children born between 1835 and 1845, nearly 25% died as infants, and another 15% died before the age of 15. Those who survived to adulthood suffered persistent malnutrition. In large cities like Boston, New York and Philadelphia, life expectancy at birth in 1830 was 24 years. On top of that, they worked an average of 78 hours a week.

Of course, all the improvements since then have come at a tremendous cost to our environment. So, things will only be "getting better" in a sustainable way if we change our habits.

One piece of good news here is that while the world's population is expected to grown from 6.5 billion to 9 billion from now to the year 2050, it's now expected to decline after that. Birth rates are dropping worldwide. In no major industrial country besides the US do women have more than 2 children on average. In China they have 1.7 — though you may not have heard, the 1-child policy does not apply to couples who are themselves only children. In Germany they have 1.4. In Italy, just 1.3. In the United States the average is 2.1.

This is added incentive to make a transition to a mindset where "growth" is measured not in terms of GNP, but GNP per capita, or some other statistic that's an even better indicator of how well people are living on average. We've got to stop thinking that bigger is better, and instead realize that better is better.

If not, we still run the danger of seriously screwing up the planet for a long time.

James Lovelock argues in this book:

that the time is past for "sustainable development" — he wants "sustainable retreat". From September 12th 2006 New York Times article:
Q. Why do you call it global heating and not global warming?

A. Warming is something that's kind of cozy and comfortable. You think of a nice duvet on a cold winter's day. Heating is something you want to get away from.

Q. What's your perception of where we're headed with even conservative predictions for growth of both populations and energy use?

A. I think we're headed straight back to the Earth's second stable state, which is a hot state that it's been in many times before in the past. It's about 14 degrees warmer than it is in these parts of the world now.

It means roughly that most life on the planet will have to move up to the Arctic basin, to the few islands that are still habitable and to oases on the continents. It will be a much-diminished world.

Q. Can you explain why you think nuclear power is so vital?

A. The really bad thing we did way back when was starting to burn things in the atmosphere to get energy. We started with fire, just cooking food, and probably could have gotten away with that. But once we started burning forests to drive the animals out as a cheap way of hunting, then we started on our downward course. What we're doing now with fossil fuels is just as bad.

We live in a nuclear-powered universe. We're the oddballs by getting energy from burning carbon.

My justification of nuclear power is that we've reached a stage now where the dire things that threaten us are so great that even the results of an all-out nuclear war pale into insignificance as unimportant compared to what's going to happen. Q. You seem to say we have to get over the idea that renewable energy sources &emdash; wind, solar &emdash; in the short run, are a useful way out of this.

A. I feel they're largely gestures. If it makes people feel good to shove up a windmill or put a solar panel on their roof, great, do it. It'll help a little bit, but it's no answer at all to the problem.

Q. What is it about this issue that you think fails to capture adequate public or political attention?

A. I think it's mainly because scientists, and I include myself amongst them, have not really understood what was going on until very, very recently. And also scientists tend to look at things much too academically.

What really got me to write the book was going to a meeting at the Hadley Center, a big climate lab near where I live, and talking to all the people there. And Sandy came with me, and we both got the impression that they were talking about the Earth as if it was another planet, not something they were actually standing on.

And they're all talking about their own separate little bit. One was talking about glaciers melting, another about tropical forests in trouble. But they didn't put it together as a whole-planet phenomenon. And when you did that, then each of their gloomy stories together became a devastating thesis.

Q. You say in the book that sustainable development is a fantasy, essentially, and you have a different notion for what needs to happen, of 'sustainable retreat'.

A. At six-going-on-eight-billion people, the idea of any further development is almost obscene. We've got to learn how to retreat from the world that we're in. Planning a good retreat is always a good measure of generalship.

Q. If you could take any facet of society &emdash; elected officials, doctors, writers &emdash; and show them one thing that you think could motivate the scale of change you're talking about, any idea what you might do?

A. I would take them on a trip to the parts of the world where the changes are now maximum, and that is the Arctic. For example, not many years ago explorers were walking with dogsleds all the way to the North Pole regarding it as a great adventure. It's only a matter of perhaps 30 years when they'll have to go there in a sailboat.

Q. You seem to have two messages at once. One is sort of a hopeful sense of the innovative and adaptable aspect of humans, and the other is that we're going to need all those skills.

A. The human species has been on the planet for a million years now. We've gone through seven major climatic changes that are equivalent to this. The ice ages were shifts in climate comparable with this one that's coming. And we've survived.

That series of glaciations and interglacials put the pressures on us to select the kind of human that could adapt. And we're the progeny of them. And we're just up against a new and different stress. Maybe we'll come out better.

We'll see!

For my July 2007 diary, go here.

© 2007 John Baez