I'm a bit behind
the times down here sometimes. I only just noticed, whilst passing
the news stand at the supermarket, that the cover story of the
last
issue of New Scientist
is about the possible non-existence of The Dark Force. I didn't
need to open it to know that it mentioned David Wiltshire, but of
course not Louise
Riofrio, Matti
Pitkanen or a whole of host of other quantum gravity
researchers who think The Dark Force is absurd.
I am this week's profilee at Norman Geras's blog. This is very pleasing to me, as my chance discovery of Norm's Solidarity in the Conversation of Human Kind (followed by his Marx and Human Nature) was an important part of my intellectual development in graduate school. There are some very important areas of politics where I believe that he is very wrong, but he's always sincerely benevolent and worth reading; and sometimes, simply right.
Don’t say that “you are going to brush your teeth”; instead “I am going to apply the force of friction to overcome the electrical bonds between my teeth and foreign matter.”
Scientists who want to describe their work on Wikipedia should not be forced to give up the kudos of a respected journal. So says a group of physicist who are going head-to-head with a publisher because it will not allow them to post parts of their work to the online encylopaedia, blogs and other forums.So, for now, feel free to talk like a physicst, but just not on Wikipedia. Let's see what happens in May.The physicists were upset after the American Physical Society withdrew its offer to publish two studies in Physical Review Letters because the authors had asked for a rights agreement compatible with Wikipedia . The APS asks ascientists to trasnfer their copyright to the sccoiety before they can publish in an APS journal. This prevents scientists contributing illustrations or other "derivative works" of their papers to many websites without explicit permission.
You know, there are really a remarkable number of bands whose names begin with "S"... There may be more "B" or "T" acts in my library, just because I own a bazillion songs by Bob Dylan and Tom Waits, but there sure are a lot of "S" artists.
This set continues to show that sing-along-ability is the most important criterion in picking FutureBaby tunes. On strict moral grounds, the Pogues have no business on such a list, not due to lyrical content, but rather the make-up of the band, but how could I not include a couple of theirs?
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The next lab visit experiments I want
to talk about are really the epitome of what I called the "NIST
Paradigm" in
an earlier post. These are experiments on "four-wave mixing"
done by Colin McCormick (who I TA'd in freshman physics, back in
the day), a post-doc in Paul Lett's lab at NIST. As Paul said when
I visited, if they had had a better idea of the field they were
dabbling in, they would've thought that what they were trying was
impossible; thanks to their relative ignorance, though, they just
plowed ahead, and accomplished something pretty impressive.
The basic scheme is laid out in this arXiv preprint, which appears to be the same as this Optics Letter (I don't have electronic access to Optics Letters, so I'm working off the arXiv text), and looks like this:
Clears everything right up, doesn't it? Well, OK, maybe I can explain a little more...
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Yet another picture taken by Kate at the National Zoo. When we arrived at the beaver pen, a bunch of keepers were inside, posing for a picture. This little guy clearly thought that humans being in his enclosure indicated that it was feeding time, and was doing his best pathetic begging.
It really just begs to be LOL'ed:
Read the rest of this post... | Read the comments on this post...Today ha been dubbed "Talk Like a Physicist Day". Why? Because we're at least as cool as pirates, that's why.
Over at Swans on Tea, Tom offers some vocabulary tips:
Use "canonical" when you mean "usual" or "standard." As in, "the canonical example of talking like a physicist is to use the word 'canonical.'"
Use "orthogonal" to refer to things that are mutually-exclusive or can't coincide. "We keep playing phone tag -- I think our schedules must be orthogonal"
"About" becomes "to a first-order approximation"
Things are not difficult, they are "non-trivial"
Large discrepancies are "orders of magnitude apart"
Other suggestions: a situation isn't "bad," it's "sub-optimal." "Finite" can mean either "really big, but not infinite," or "really small, but not zero." If you really want to sound advanced, something that moves from one state to another slowly-- say, a highway driver who takes a mile and a half to move from one lane into the other-- does so "adiabatically."
I know I'm missing some obvious verbal tics. Leave your suggestions in the comments.
Read the comments on this post...Click here for all of my del.icio.us bookmarks.
There are lots of old superstitions - some of them we still live
our lives by. Running a large experiment like D0 is no different.
For example, there are a set of ducks along the console - the rumor
is if they aren’t there then the whole system will cease to
operate. I don’t think anyone has been brave enough to remove them…
I pulled the following quote from a recent shift report:
Beam was nice for a while. Then while talking to Bill Lee about losing the beam, we lost the beam, thereby illustrating Bill’s spooky powers in the control room.
Bill has long been making our control room run smoothly, and should know the lesson: don’t talk about loosing the beam! You’ll jinx it!! [Technical reason: apparently an important power supply went out of allowed operating range].
New Yorker: ...The rumor, according to one (unofficial) e-mail: “Oscar-winning producer Brian Grazer (Da Vinci Code, A Beautiful Mind, American Gangster) is looking for a new cultural attaché.” The e-mail explained:
This person would be responsible for keeping Brian abreast of everything that’s going on in the world; politically, culturally, musically. . . . They’re also responsible for finding an interesting person for Brian to meet with every week . . . an astronaut, a journalist, a philosopher, a buddhist monk. . . . There is LOTS of reading for this position! Grazer may ask you to read any book he’s interested in. You’ll probably get to read about 4 or 5 books a week and you may be required to travel with him on his private plane to Hawaii, New York, Europe—teaching him anything he asks you about along the way. . . . You will also be provided with an assistant. . . . Salary is around $150,000 a year. . . . You will be to Grazer what Karl Rove was to Bush.
...Michael Rosenberg, the president of Imagine, the production company Grazer owns with Ron Howard, said that about a hundred would-be attachés have e-mailed résumés since word of the job got out. One was Ed Cooke, twenty-six, a British writer and education consultant. His résumé: philosophy-and-psych degree from Oxford, three languages, a demonstrated interest in “the philosophy of cricket.” “This seemed like a job that would suit me,” Cooke said. He’d sent in a list of interesting people: the medieval scholar Mary Carruthers; the cricket star Shane Warne; Dmitri Nabokov.
But Cooke didn’t make the final cut. By last week, Grazer’s staff had already narrowed the potential attachés down to four finalists, who would interview with the boss. “I’ve met a lot of good candidates,” Grazer said, reached on his cell phone en route to a meeting with the screenwriter for “Angels and Demons.” He said that he’d been hiring cultural attachés for twenty years, ever since he asked Jonas Salk’s assistant to help him track down interesting people in science. Fifteen or twenty people have held the job since then. (The “attaché” title started out as a joke.) “They have to be really resourceful,” Grazer said. “I like to meet people in dangerous organizations, and my cultural attaché finds out who that person is—who runs the Yakuza, or the Masons, or MI5.” The best attaché so far, Grazer said, has been Brad Grossman, the current one, who is leaving the post, after four years. Grossman is thirty-two; he owned a tutoring business before taking the job, and Grazer said that he is especially good at explaining the things he’s asked to learn about—bacteria or makeup or superdelegates. “I’m looking for a person who has that teacherlike quality,” Grazer said. “Also, it’s good to have a person who is a connector, who is liked by people.”
Grazer has had one bad attaché experience. “A few years ago, I hired this really smarty-pants Harvard guy,” he said. “He was just remarkably lazy. If he didn’t get the Wall Street Journal on his desk, it was like it didn’t exist.” Still, he said, the experience came with a lesson: “Under no condition can you teach curiosity.”
Before Grazer became a successful producer, he was—like most people— his own cultural attaché. Two weeks ago, he found a letter he’d written to the physicist Edward Teller during that period. “It made me remember how much work it was,” Grazer said. “I had to do the begging and grovelling and ass-kissing myself. I had to find the newspapers and magazines. Even then, I put so much thought and effort into trying to meet and learn from the people who mattered to me.”
The past few weeks I’ve often been going down to the IAS in Princeton on Thursdays to hear talks given as part of the special program there this semester in mathematics. These talks included a series of five talks by Witten; notes from David Ben-Zvi and Sergei Gukov are available here.
The first three talks concentrated on the existence of a very special superconformal six-dimensional QFT, and information that could be derived from what is known of its properties. Such a theory is an inherently quantum object, lacking a usual sort of classical limit or Lagrangian formulation. Witten compares it to the holomorphic conformal field theory that appear as “square roots” of the WZW model. These field theories are closely related to the representation theory of loop groups and at the core of a several important mathematical developments of the last couple of decades. The mathematical significance of the six-dimensional theory remains much more mysterious, and Witten argues that understanding this mystery is a very worth goal for both mathematicians and physicists. . For more about this, see the article Conformal Field Theory in Four and Six Dimensions, based on his lecture at the Oxford conference in honor of Graeme Segal’s 60th birthday back in 2002. Taking the six dimensions to be the product of a torus and a four dimensional space, the existence of such a superconformal six dimensional theory implies an SL(2,Z) symmetry of N=4 Super-Yang-Mills on the four dimensional space. This includes the famous Olive-Montonen non-abelian electric-magnetic symmetry that is responsible for Langlands duality in Witten’s 4d QFT approach to Geometric Langlands.
The last two talks of the series dealt with a different topic, boundary conditions in N=4 SYM. Taking this theory on the half-space with boundary conditions, one can ask about the implications of non-Abelian electric-magnetic duality for these boundary conditions. Witten has recently been working on this subject with Davide Gaiotto, he’ll be talking about it later this month at a Stony Brook symposium in honor of C. N. Yang and Jim Simons, and I assume a paper will appear sooner or later. In his IAS lectures Witten was talking to mathematicians and arguing that “universal” operations (ones that can be done uniformly for all Riemann surfaces) in geometric Langlands should all come from the properties of these boundary conditions. Note that in this work what appears is the full N=4 SYM theory, not just the topological twisted version. This theory plays a central role in AdS/CFT, so if new information about its physics arises from this study, this should be directly interesting for physics, although Witten did not discuss this in his talks.
The two sorts of boundary conditions that get related by duality are analogs of Neumann and Dirichlet boundary conditions. The Neumann boundary conditions involve superconformal 3d QFTs, examples of which were studied by Intriligator and Seiberg in their 1996 paper Mirror Symmetry in Three Dimensions. Witten has previously worked on this kind of thing in the Abelian case, see here.
During these visits to the IAS I got the chance to meet Meng-Chwan Tan, who is there in the Physics group this year. He has been working on a different QFT approach to geometric Langlands, one that is purely two-dimensional and based in conformal field theory, using (0,2) sigma models on flag manifolds, and has just posted a the revised for publication version of his paper on the subject here. This is much closer to the approach to geometric Langlands via conformal field theory that Edward Frenkel has described here.
In other geometric Langlands news, there was a workshop on Homological Mirror Symmetry recently in Miami, with notes from many of the talks available here (and a blog posting by Joel Kamnitzer here). And there’s another one (notes here from David Ben-Zvi) going on this week at the IAS. I better stop now, go and get some sleep so I can head down there tomorrow morning to catch the last day of it.
I spent a great morning at the CfA vising the plate scanning project DASCH. The plate scanner is beautiful, and I saw it in action. I also saw the 100 tons of plates in the plate stacks, and was suitably impressed with the care with which they are maintaining and carrying forward all the meta-data they have. Then they apply some good automatic calibration and are building an archive. I learned from Josh Grindlay that there are enough plates in the Harvard archive alone to have fully imaged the sky 500 times over.
Earlier in the morning I met with Chris Stubbs and discussed
many issues related to performing precise calibration of
astronomical data sets and providing enough information back to
users that the data set will play well with others. We put in some
good hours on truly fundamental things such as: What does a
telescope really measure?
(integrals of the photon phase-space
density, in my view) and All precise observations are
necessarily relative to astronomical sources with (fundamentally)
unknown spectral properties.
Stubbs is a deep thinker, and
obviously I would say that because he thinks about these things
much as I do! Now here's to him taking over the world and bending
it to his will.
Y Combinator (YC) is a small Cambridge-based firm that for the past few years has been carrying out a remarkable experiment. What they’ve been doing is investing money and training in (mostly) young hackers, helping them get technology companies up and running to the point where more more conventional investment processes like venture capital can kick in. Many YC funded companies have been successful, with several making their founders wealthy at an early age.
At first glance, YC may appear only of interest to business or technology people. In fact, there are broader things one may learn from the model, with applications and importance outside business and technology.
If you’re not familiar with how YC works, it goes something like this. Twice a year, YC calls for applications to be submitted, either for its Winter or its Summer programs. Applications are submitted by small teams of people (”founders”), typically in their twenties, who would like to start or have recently started a technology company. YC evaluates the applications, and the best are asked to join the YC program. Successful applicants typically receive $5k + $5k per founder to support them for three months, and are required to move to Boston (for the Summer program), or the San Francisco Bay Area (for the Winter program). All the YC teams meet together once or twice a week, to talk with each other and with the YC partners, as well as with a changing cast of expert entrepeneurs specially brought in from outside. The three month program concludes with “Demo Day”, where the founders demonstrate what they’ve built to a large group of angel investors and venture capitalists, in the hopes of sparking further interest. In return for this program, the founders give up a small percentage of their company, typically between 2 and 10 percent.
What makes the YC program successful is that YC have identified a large group of people whose talents were previously undervalued and underutilized, in large part because of their age and lack of experience. For more than thirty years, high-school geeks have played with technology, gone off to university, where they continue to play with technology, often doing astounding and innovative things, but rarely having the entrepeneurial skills or connections to turn their ideas into marketable products. At the end of it all, they go off to work for a big established technology company like Microsoft.
YC has asked a big “what if?” question: what if we gave these talented people an opportunity to build their own company, from the ground up, and gave them training in entrepeneurial skills they lack, complementary to their existing technical ability? Might it be that if we provide this training (which is relatively easy to do), then these people will create more value than if they were off working for big existing technology companies?
It is evident from the above description that this process can be abstracted away to a core unrelated to technology:
What’s special about YC is the group they’ve identified: young hackers, whose lack of experience means they often have a hard time being considered seriously by existing investors such as venture capitalists. Ironically, this is in part because the venture fund model typically involves investments that are, at a minimum, hundreds of thousands of dollars. Given a choice between investing that money in a 35-year old Harvard MBA’s startup, and a team of three unshaven 21 year-old hackers, most venture partners will go for the Harvard MBA. Part of YC’s insight is that in 2008 many technology companies can be launched for just a few tens of thousands of dollars, far less than the venture funds provide.
Other organizations have adopted an analogous strategy to YC, but for a different group of otherwise undervalued people. A good example is microfinance organizations like the Grameen Bank, which provide small loans to assist entrepeneurs in the developing world. The success of the Grameen Bank indicates that investors previously underestimated the talents of the lendees to build successful businesses. An interesting social consequence common to YC and the Grameen Bank is that both empower people who are otherwise somewhat disenfranchised. (Obviously, the effect is far greater in the case of the Grameen Bank.)
This process of identifiying a talented group of people who are undervalued by the investment market is a curious one. An uncritical advocate of the free market might counter that such people shouldn’t exist - surely investors would have already tracked them down, and offered to invest. In fact, YC is a clear case where (up to now) the market has failed badly, due to the blinkered narrowness of investors. Is it more risky to offer one million dollars to finance a Harvard MBA in their new technology venture, or to fund twenty groups of talented twenty-one year old hackers, at a cost of about $50k each (including the training costs and other overheads)? My money would be on the twenty-one year olds to make a greater aggregate return, but I suspect most investors would feel much safer going with the Harvard MBA - even if they fail, it’s a lot easier to defend your choice to your peers.
What other undervalued sources of human capital might this general model be applied to? When I started to think about this question, I quickly came up with dozens of possible groups. Here’s the first few that came to mind:
I spent the day at Harvard between the CfA and the Institute for Innovative Computing, where I gave my automated astrometry and open-source sky survey talk. I also spent some time chatting with Willman about our projects with Zolotov, and with the IIC staff about computation in science.
I've lost count, but there is a new Carnival of Space over at Missy's place
Read the comments on this post...Why do powerful, intelligent, and accomplished people so often exhibit cluelessness or ignorance? (Examples can be supplied on demand, in the unlikely event you need them.)
I don’t mean to rip on powerful people, many of whom become powerful because of outstanding personal traits. But I do think it’s worth understanding the puzzle of why so many people do great things in their youth, and then do apparently sillier things as they get older.
I think my post about the bias towards power contains a partial explanation: powerful people’s ideas often aren’t tested as rigorously as those of the less powerful, and they find it easier to act while ignoring good advice. As an example, a regular Joe with an idea for starting a company has to convince other people of the idea in order to attract investment. A wealthy entrepeneur finds it much easier to get silly ideas funded, in part by investing their own wealth, and in part because other people give undue weight to their words.
(This is also why comics and superheros like Spiderman are interesting: they show what happens when basically well-intentioned people can act without constraint. The results often aren’t pretty.)
However, I think the bias towards power is only part of an explanation. Another part is that powerful people are often far too busy and focused. If you don’t create time just to fool around (”purposeless delectation in ideas” was Gian-Carlo Rota’s lovely phrase), you end up narrow, clueless, and irrelevant. It’s funny to hear that CNN’s Larry King has never used the net, or that George Bush (the elder) was amazed by supermarket barcode scanners in 1992, but, really, these people must have some massive blind spots.
Looking at this segment of the playlist, it's clear that I was, consciously or not, giving a good deal of weight to how well a given song works as a sing-along. For whatever reason, this chunk of the artist alphabet is loaded with tunes that are maybe a little dubious content-wise, but good fun to sing along with.
Read the rest of this post... | Read the comments on this post...As I mentioned a few days ago, I
visited Luis Orozco's lab during our trip to DC last week. I
already talked about his cavity QED stuff, but that's only one of
the projects under development. He's also working on a
next-generation apparatus for the laser cooling and trapping of
francium, to be done at the TRIUMF accelerator in Vancouver--
francium is an element with no stable isotopes, and at most a few
grams of it exist on the earth at any given moment. Luis and his
students demonstrated the laser cooling of francium a few years
back, using atoms made in an accelerator at Stony Brook out on Long
Island.
Why would anyone care about francium? The reasons are laid out in "Measurement method for the nuclear anapole moment of laser-trapped alkali-metal atoms" (link to arXiv preprint, because it's free; the published version is this Physical Review A paper). Francium is of interest precisely because it's a heavy element with no stable isotopes. The very large nucleus of francium means that weak interactions can produce an anapole moment in the nucleus, which would be a signature of parity non-conservation (PNC), and a possible indicator of new physics. They have an idea for a way to measure this using precision spectroscopy.
Read the rest of this post... | Read the comments on this post...Over at the new(ish) Of Two Minds, Shelley has posted a video giving advice on scientific presentations from a couple of guys at Michigan. They offer a few quick tips to giving better presentations:
The central point is really to put the focus on the data, not the words or slides.
The one specific tip I would add to their list is this: When you put up a graph, you should clearly identify what is being plotted on what axes. The first thing you say should be "Here we have YYYY on the vertical axis versus XXXX on the horizontal axis," so that everybody knows what you're showing, without having to squint to read the labels.
Read the rest of this post... | Read the comments on this post...We live in a short-attention-span age. I have a huge array of feeds spewing information at me like the proverbial firehose, so I often don't do more than look at the headline and RSS excerpt, and I don't think I'm alone.
Given that, it's more important than ever that the headlines given to articles actually, you know, match the contents. For example, when I see a story in the New York Times headlined Environmental Agency Tightens Smog Standards, I would like this to accurately reflect the contents of the story. When the first sentence of the story is:
The Environmental Protection Agency announced a modest tightening of the smog standard on Wednesday evening, overruling the unanimous advice of its scientific advisory council for a more protective standard.
I feel like I've been misled by the people writing the headlines. The headline is factually accurate, but nearly the opposite of the actual story in terms of connotation. "Environmental Agency Tightens Smog Standards" makes me think "Yay, progress!" while the story is yet another in a long litany of stories about political hacks ignoring or overriding scientific expertise.
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Thirsting for some stunning
pictures of the LHC? Check out this
article in the National Geographic
magazine. Make sure to look at the photo-gallery that comes along
with the article. Some of the pictures — like the ALICE and CMS
detector pictures are really stunning (ATLAS too, of course, but
we’ve seen that one already).
BTW — the ATLAS detector is no longer all that photogenic on a grand scale - the cavern is now so full of bits of the detector it is quite difficult to get an idea of how big it is - all your site lines are blocked!
The picture is one of mine of ATLAS. The ones from ATLAS are much better!
My apartment was broken into last year. Today my insurance company dropped by to inspect the place and interview me. They asked me all sorts of detailed questions about the items that were taken - cost, how old, etc. At the end, they told me how much money they would give me… and then wrote a check on the spot! Amazing!
I have lately been led to the conception of a new system, or rather family of systems, of non-commutative roots of unity, which are entirely distinct from the i j k of quaternions, though having some general analogy thereto.The basic icosian calculus describes moves through the vertices of a dodecahedron and is generated by three kinds of move, let us say $a$, $b$ and $c$, such that $a^{2} = 1$, $b^{3} = 1$, $c^{5} = 1$ and $c = ab$. Observe the appearance of the rules for the modular group. All these moves apply to the oriented graph and are given by
At least one
crazy retired physicist
has incorporated this calculus into a spacetime model
for the leptons and quarks, in which the $E8$ lattice magically
appears out of paired quaternion like (ie. octonion) operations. A
triality involving three $E8$s is briefly discussed.
...the wealth boom — and the explosion in the number of multi-millionaires — has created entirely new pricing levels for escorts. According to the complaint, the Emperors Club escorts charged between $1,000 and $5,000 an hour, depending on their “rankings.” Clients could also pay between $25,000 and $50,000 for a three-day visit. It may be the world’s oldest profession: but the prices reflect the new realities of wealth.
The escorts were well-versed in the lucrative potential of this new market. In the complaint, a prospective escort in London turns down the job based on price, saying that £500 an hour for starting escorts — close to $1,000 an hour — was chump change, especially since it didn’t incldue dinner.
“This is the kind of money I make very easily on photoshoots,” the woman said.
...According to a survey by Russ Alan Prince, president of Connecticut-based wealth-research firm Prince & Associates, in his book “The Sky’s The Limit,” a sizable percentage of the super wealthy use escorts. He surveyed 661 people who owned private jets. It found that 34% of males and 20% of females had paid for sex.
The most popular reason was “unique experiences” (71%), followed by “higher quality experiences” (57%). Conventional wisdom says that the rich visit escorts to avoid messy break-ups or extra demands for cash. But the study shows otherwise: “No strings attached,” ranked last as a reason.
“With the wealthy,” Mr. Prince says “it’s all about power and control and new experiences.”
apparently some people are stuck in a broken elevator at the top of
the Green Bank Telescope
The 2008 Templeton Prize was announced today. It goes to Michael Heller, a Polish cosmologist, philosopher and Catholic priest, for “sharply focused and strikingly original concepts on the origin and cause of the universe.” The full name of the Templeton Prize is the “Templeton Prize for Progress Toward Research or Discoveries About Spiritual Realities” Its goal is to promote bringing science and religion together by awarding a prize of 820,000 pounds sterling, the single largest award given to an individual. Prince Charles somehow gets into the picture too, since he will be presenting the prize to Heller in a private ceremony at Buckingham Palace in early May.
In recent years Heller has been interested in non-commutative geometry as way to study quantum gravity and cosmology. According to Heller, the crucial question of cosmology is “Can the Universe Explain Itself?”, and associated with the awarding of this prize, the Templeton Foundation will be hosting a discussion of the associated question “Does the Universe Need to Have a Cause?”.
The Templeton press materials describe Heller as “initiating what can be justly termed the ‘theology of science.’” His nomination for the prize says that:
It is evident that for him the mathematical nature of the world and its comprehensibility by humans constitute the circumstantial evidence of the existence of God.
I’m rather dubious about the way Heller mixes theology, philosophy and cosmology, but, unlike much harder-nosed physicists these days, at least he seems to recognize the problems with the Multiverse.
Heller intends to use the prize money to create a Copernicus Center in Cracow to further research and education in science and theology.
Times of India: ...as many as 12% [of] scientists and 38% [of] doctors in the US are Indians, and in NASA, 36% or almost 4 out of 10 scientists are Indians.
If that's not proof enough of Indian scientific and corporate prowess, digest this: 34% employees at Microsoft, 28% at IBM, 17% at Intel and 13% at Xerox are Indians.
As noted in the previous FutureBaby playlist post, I started doing this after hearing Don McLean's "American Pie" on the radio while running errands the other day. Amusingly, you will note that that song is not present in this part of the list-- that's because I don't have an electronic copy of it. Which I suppose explains why I haven't heard it much until the other day in the car...
There's some stuff here that would be a little... incongruous to hear sung by a small child, but nothing too offensive, I don't think. And they're all songs I like, which is the important thing.
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Nir
Shaviv, professor at the HUJI (click!) and a leading expert in
cosmoclimatology, replies to a criticism by RealClimate.ORG.