Friend of the Blog (and Dark Energy Song performer) Lloyd Knox, Professor of Physics at the University of California Davis, has teamed up with undergraduate students David Gribble and Justin Smith and graduate student Damien Martin to launch a new endeavor – The Spherical Cow Company – which

… produces short documentary videos to demonstrate the explanatory power of simple physical models and to help us understand and aesthetically appreciate the natural world.

Their first video discusses the Cosmic Microwave Background – a central feature of modern cosmology, and one of our most important tools for exploring the universe.

In this episode, Lloyd shamelessly follows the well-worn path of other entertainers before him in pushing their children – in this case his son Teddy – into the business. Lloyd and Teddy explore what the CMB means on their kitchen table with a pen and paper, cutting to more high-tech descriptions of the material where appropriate.

It’s entertaining stuff, while retaining the nice feel of sitting down to an informal chat with an expert. I think you’ll enjoy it and, if so, I hope you’ll return to take a look at their future efforts.

This past week has seen a lot of news stories about a “Manhattan-sized” plume of oil found in the Gulf of Mexico by researchers near the site of the BP Deepwater Horizon well. This sent my BS detector into the yellow zone, so I have been trying to get a better idea of just how much oil remains in the Gulf from this disaster. It’s definitely not gone.

So I went to Wikipedia. There, you can find a reference to a New York Times article from the beginning of August, where the total volume of the leak was estimated to be 780,000 cubic meters of oil. Now, that’s clearly in the category of “reasonable guess” – no one knows for sure. But it is very unlikely to be a factor of two larger or smaller than that, so let’s just use that for now. There are a lot of other uncertainties, for example the amount of natural gas (methane) that came out with the oil, how the flow rate changed with time, and so on. But again, let’s just ignore those.

How big is 780,000 cubic meters? Simply taking the cube root of this number, this is the volume of a cube 92 meters on a side. It would look something like this next to the Pentagon:

I can imagine two reactions to this comparison: 1) Damn, that’s a lot of oil! 2) That’s tiny compared to the volume of the Gulf of Mexico! (I bet one’s political views might play a role in which reaction comes first…)

If we were to take this volume and spread it out in a layer 1 millimeter thick, it would cover an area of 780 million square meters, which is a square about 28 kilometers on a side. The satellite images of the oil slick showed affected regions much larger than that, from which I conclude that the thickness of the surface layer must have been much less than 1 millimeter at those times. (But check my math, somebody!)

If all the oil were dissolved uniformly into the Gulf, which has a total volume three million billion times the size of the leak, the concentration would be about one third of one part per billion. That’s an interesting number all by itself, and not at all as small as it seems. But not all the oil leaked is in the Gulf – much of it evaporated and a good deal has been consumed by bacteria. But the rest of it went somewhere, right?

Now to the underwater plume. In the abstract of the Science Magazine paper that led to all the news stories, the authors said “Our findings indicate the presence of a continuous plume over 35 km in length, at approximately 1100 m depth that persisted for months without substantial biodegradation.” I cannot find the word “Manhattan” anywhere in their article, and so I have to conclude this was some mainstream media (WSJ?) person’s rather inept attempt at putting the size of the plume into perspective. It was parroted endlessly in the media as if it had meaning. In fact it’s quite misleading – clearly the term “Manhattan-sized” conjures up images of the whole island of Manhattan along with all the tall buildings…but as we have seen the total volume of oil leaked into the Gulf is about the size of one of those buildings.

So what is this plume? The authors define it as “a discrete spatial interval with hydrocarbon signals or signal surrogates (i.e., colored dissolved organic matter or aromatic hydrocarbon fluorescence) more than two standard deviations above the root-mean-square baseline variability.” That is, a place in the water where there is clearly oil present at detectable levels. It can be at quite low concentrations and still be detectable. One of the article’s main findings was that “Gas chromatographic analyses for only monoaromatic hydrocarbons of several water samples gathered using survey guidance confirm benzene, toluene, ethylbenzene, and total xylenes (BTEX) concentrations in excess of 50 μg L^–1 within the plume at 16 km downrange from the well site.” This is all bad stuff we don’t want in the water or getting into the food we eat.

I assume a lot more scientific research will need to be done to know the actual damage that the presence of these oil components will do to marine life, the fisheries, and the food chain. The authors took a stab at making an estimate of how much oxygen depletion was occurring due to biodegradation of the oil, concluding that “it may require many months before microbes significantly attenuate the hydrocarbon plume to the point that oxygen minimum zones develop that are intense enough…to threaten Gulf fisheries.” That’s good news for marine life, I assume, but means that the subsurface oil will take quite some time to be bioegraded, which is bad in the longer term. So why hasn’t the media talked about that aspect of the article?

There is no question that this was a huge amount of oil leaked into the Gulf and that the impacts will be felt for many years to come. It is an epic disaster by any measure and may have consequences no one has considered yet. But we have to be rational about the real impacts of the disaster, and rational about the real risks involved in deep water drilling. The only way is to continue vigorously the kind of research we saw in the Science Magazine article, and debate the findings openly. BP needs to release publicly everything it knows about the spill.

I have to agree with Jerry Coyne here: the program on Faith and Science at this year’s World Science Festival is a mistake. I went to last year’s Festival, and I have great respect for Brian Greene and Tracy Day for bringing together such a massive undertaking. It would be better if they didn’t take money from the Templeton Foundation, but money has to come from somewhere, and I’m not the one paying the bills. I don’t even mind having a panel that talks about religion — it’s a big part of many people’s lives, and there are plenty of issues to be discussed at the intersection of science and religion.

But it would be a lot more intellectually respectable to present a balanced discussion of those issues, rather than the one that is actually lined up. The panelists include two scientists who are Templeton Prize winners — Francisco Ayala and Paul Davies — as well as two scholars of religion — Elaine Pagels and Thupten Jinpa. Nothing in principle wrong with any of those people, but there is a somewhat obvious omission of a certain viewpoint: those of us who think that science and religion are not compatible. And there are a lot of us! Also, we’re right. A panel like this does a true disservice to people who are curious about these questions and could benefit from a rigorous airing of the issues, rather than a whitewash where everyone mumbles pleasantly about how we should all just get along.

I’m not as much of an anti-Templeton fundamentalist as some people are; I won’t take money from them, but I will cooperate with institutions and organizations that do take money from them, even as I grumble about it. (Money laundering as the route to moral purity.) But this event is a perfect example of the ultimately pernicious influence that Templeton has. I disagree with Jerry and others who consider Templeton money a “bribe” to people who are willing to go along with their party line; I have no doubt that Ayala, Davies, Pagels and Jinpa will express only views that they sincerely hold and would still hold in the absence of any monetary reward. What Templeton does is that it hands people with those views a giant megaphone. Francisco Ayala is a respected scientist who happens to believe that science and religion complement each other rather than coming into conflict; that’s fine, although somewhat unremarkable. But then he wins the Templeton Prize, and that exact same opinion gets plastered all over the media.

Panels like this one at the WSF are the same story. Maybe exactly the same event would have been organized even if Templeton had nothing to do with the Festival; but I doubt it. (Update: upon reflection, I don’t know what the process was by which the event was organized, and I shouldn’t cast dark aspersions in the absence of evidence. My real point is that I don’t think that the panel should have happened the way it did, and I don’t want to detract from that.) Plenty of science festivals and museums seem to get along perfectly well without discussing religion at all. And if you did want to discuss it, there’s no way that an honest investigation into how scientists feel about religion would end up leaving out some fully committed atheists who would be pretty uncompromising towards belief.

Four hundred years after Galileo turned his telescope on the heavens, it’s incredibly frustrating that we still have debates over whether the world can be described in purely naturalistic terms, rather than accepting that insight as an amazing accomplishment and moving on to the hard work of articulating its consequences. It’s a shame that the World Science Festival is helping to keep us back, rather than moving us forward.

One of the many places I’ve been traveling to recently is a bit unusual: the Linda Hall Library in Kansas City, Missouri. For one thing, it’s a private library; like the Huntington Library in Pasadena, it’s supported almost entirely by private funds. For another, Linda Hall is completely dedicated to science, technology, and engineering. While visiting, I asked what they considered their peer institutions to be — the other science libraries they might be compared to. Nobody could think of any. It seems to be a completely unique place.

I got to tour deep into the bowels of the building, where stacks of journals and scientific reports seem to stretch for ages. The library does a brisk job lending books and articles to other institutions; when you need a technical note from 1923 that tells you how a certain bridge was put together, this is the place to go. There is also an amazing rare-book collection, some of which was being put on display as part of an exhibition entitled “Thinking Outside the Sphere: Views of the Stars from Aristotle to Herschel.” I got to leaf through a first edition of Newton’s Principia, which I have to say was pretty awesome. I didn’t find any mistakes, but my Latin is a bit rusty. Here are the three Laws of Motion, right near the beginning of the text.

The library also adds to the intellectual life of Kansas City by sponsoring public lectures. I followed Sara Seager and Seth Shostak in a series about extraterrestrial life. Not my area of expertise by any means, but they asked me to talk about time travel, which I do know something about. (At least by the standards of other human beings, for which neither “time travel” nor “extraterrestrial life” are subjects of true expertise anywhere.)

Dr. Sean Carroll – The Paradoxes of Time Travel from Linda Hall Library on Vimeo.

Of course I also had some BBQ while in KC. One does not live by the life of the mind alone.

Timothy Ferris, in The Science of Liberty:

In 1900 there was not a single liberal democracy in the world (since none yet had universal suffrage); by 1950 there were twenty-two.

Tyler Cowen at Marginal Revolution has an ongoing series of posts in which he highlights “good sentences.” At first the conceit bugged me a bit, as how good can a single sentence be? It’s not like you have space to develop a sensible argument or anything.

But that’s the point, of course. A really good sentence packs a wallop because it fits an enormous amount into very few words. One technique for doing that is to exhibit an underlying assumption that is a remarkable claim in its own right. If I were to have tried to make the point that Ferris makes above, it would have been something like this:

Liberal democracies were established in fits and starts over a period of hundreds of years. The first major steps happened in countries like Britain, the United States, and France, where aristocratic systems were replaced (with different amounts of violence) by rule by popular vote. But I would argue that a true liberal democracy is one that features universal suffrage — every adult citizen has a right to participate. By that standard, there weren’t any liberal democracies in existence in the year 1900; but fifty years later, there were twenty-two.

Makes the point, but it’s a somewhat ponderous collection of mediocre sentences, rather than a single one of immense power. That’s the difference between someone who writes things, like me, and a true writer. I’m trying to learn.

Ferris’s book seems excellent, although I’ve just started reading it. It has a provocative thesis: the Enlightenment values of liberal democracy and scientific reasoning didn’t simply arise together. The emergence of science is rightfully understood as the cause of the democratic revolution. That’s the kind of thing I’d be happy to believe is true, so I’m especially skeptical, but I’m looking forward to the argument.

We’re very happy to have a guest post from Malcolm MacIver. See if you can keep this straight: Malcolm is a professor in the departments of Mechanical Engineering and Biomedical Engineering at Northwestern, with undergraduate degrees in philosophy and computer science, and a Ph.D. in neuroscience. He’s also one of the only people I know who has a doctorate but no high school diploma.

With this varied background, Malcolm studies connections between biomechanics and neuroscience — how do brains and bodies interact? This unique expertise helped land him a gig as the science advisor on Caprica, the SyFy Channel’s prequel show to Battlestar Galactica. He also blogs at Northwestern’s Science and Society blog. It’s a pleasure to welcome him to Cosmic Variance, where he’ll tell us about robots, artificial intelligence, and war.

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It’s a pleasure to guest blog for CV and Sean Carroll, a friend of some years now. In my last posting back at Northwestern University’s Science and Society Blog, I introduced some issues at the intersection of robotics, artificial intelligence (AI), and morality. While I’ve long been interested in this nexus, the most immediate impetus for the posting was meeting Peter Singer, author of the excellent book ‘Wired for War’ about the rise of unmanned warfare, while simultaneously working for the TV show Caprica and a U.S. military research agency that funds some of the work in my laboratory on bio-inspired robotics. Caprica, for those who don’t know it, is a show about a time when humans invent sentient robotic warriors. Caprica is a prequel to Battlestar Galactica, and as we know from that show, these warriors rise up against humans and nearly drive them to extinction.

Here, I’d like to push the idea that as interesting as the technical challenges in making sentient robots like those on Caprica are, an equally interesting area is the moral challenges of making such machines. But “interesting” is too dispassionate—I believe that we need to begin the conversation on these moral challenges. Roboticist Ron Arkin has been making this point for some time, and has written a book on how we may integrate ethical decision making into autonomous robots.

Given that we are hardly at the threshold of building sentient robots, it may seem overly dramatic to characterize this as an urgent concern, but new developments in the way we wage war should make you think otherwise. I heard a telling sign of how things are changing when I recently tuned in to the live feed of the most popular radio station in Washington DC, WTOP. The station had commercial after commercial from iRobot (of Roomba fame), a leading builder of unmanned military robots, clearly targeting military listeners. These commercials reflect how the use of unmanned robots in the military has gone from close to zero in 2001 to over ten thousand now, with the pace of acquisition still accelerating. For more details on this, see Peter Singer’s ‘Wired for War’, or the March 23 2010 congressional hearing on The Rise of the Drones here.

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A few days ago the following headline on the New York Times website caught my eye: Seeing What the Hubble Sees, in Imax and 3-D. There are two reasons this headline is worthy of note. First, it is amazing that an IMAX movie about the Hubble Space Telescope exists at all, and is worth mentioning on the front (web)page of the NYT. Hubble is a part of the popular imagination, and may be the object most closely tied with Science in the eyes of the general public (even more than the LHC). Furthermore, it is absolutely astounding that NASA launched hundreds of kilos of camera equipment and film into orbit, and spent valuable astronaut time (both on the ground and in space) to pull off the filming. I would claim one of the lasting legacies of the Apollo missions to the Moon are the photographs, and in particular Earthrise. That single photograph of our home as a small blue marble against the vastness of space put our planet into proper perspective for the very first time. NASA is well aware that part of its mission is to light up the public imagination, getting us to peer past our limited horizons, and out into the vast Universe beyond. This film is part of that tradition.

The second interesting aspect of the headline is that it’s nonsensical. Hubble has only one eye. It has one mirror. It can’t perceive depth, and therefore can’t see in 3-D. We see slightly different images in each of our eyes, and then a fairly impressive difference engine (called a “brain”) figures out the depth to everything we are looking at, and whether that rock is about to bonk us on the head and we need to duck NOW! 3D movies (such as Alice and Avatar) use circularly polarized light, and glasses with different filters in each lens, to produce the different images for each eye. (The light is circularly polarized so that, if you tilt your head, it all still works; the old linear polarization approach didn’t do this, and had a tendency to make one feel motion sick [at least, it did for me]).

In general astronomical sources are too far away for us to discern distance using parallax. That’s why the night sky looks “flat”, even though the planets and stars and galaxies are at a tremendous range of distances. If you wanted to be able to directly “see” the distance to the nearest star, in the same way that you ascertain the distance to an approaching lion, your eyes would need to be separated by roughly 10 billion km. (Eye separation = Distance*Angle. The human eye has an angular resolution of roughly 1 arcmin = 0.0003 radians, and the nearest star [Proxima Centauri] is 4 lightyears = 3.8e13 km.) The way we figure out distance in Hubble images is by using color information (and, in particular, the spectra) to discern recession velocity (redshift), and thereby distance (using Hubble’s law). This is not something we do with our eyes (although we do use color information to discern temperature; you’re unlikely to grab something that is so hot it’s glowing blue). Hubble sees a purely two-dimensional Universe. So “seeing what the Hubble sees …in 3-D” is a contradiction in terms. Was the headline carefully crafted to see if we were paying close attention?

(Update: further discussion here and here.)

Sam Harris gave a TED talk, in which he claims that science can tell us what to value, or how to be moral. Unfortunately I completely disagree with his major point. (Via Jerry Coyne and 3 Quarks Daily.)

He starts by admitting that most people are skeptical that science can lead us to certain values; science can tell us what is, but not what ought to be. There is a old saying, going back to David Hume, that you can’t derive ought from is. And Hume was right! You can’t derive ought from is. Yet people insist on trying.

Harris uses an ancient strategy to slip morality into what starts out as description. He says:

Values are a certain kind of fact. They are facts about the well-being of conscious creatures… If we’re more concerned about our fellow primates than we are about insects, as indeed we are, it’s because we think they are exposed to a greater range of potential happiness and suffering. The crucial thing to notice here is that this is a factual claim.

Let’s grant the factual nature of the claim that primates are exposed to a greater range of happiness and suffering than insects or rocks. So what? That doesn’t mean we should care about their suffering or happiness; it doesn’t imply anything at all about morality, how we ought to feel, or how to draw the line between right and wrong.

Morality and science operate in very different ways. In science, our judgments are ultimately grounded in data; when it comes to values we have no such recourse. If I believe in the Big Bang model and you believe in the Steady State cosmology, I can point to the successful predictions of the cosmic background radiation, light element nucleosynthesis, evolution of large-scale structure, and so on. Eventually you would either agree or be relegated to crackpot status. But what if I believe that the highest moral good is to be found in the autonomy of the individual, while you believe that the highest good is to maximize the utility of some societal group? What are the data we can point to in order to adjudicate this disagreement? We might use empirical means to measure whether one preference or the other leads to systems that give people more successful lives on some particular scale — but that’s presuming the answer, not deriving it. Who decides what is a successful life? It’s ultimately a personal choice, not an objective truth to be found simply by looking closely at the world. How are we to balance individual rights against the collective good? You can do all the experiments you like and never find an answer to that question.

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We’ve collected enough data in our What Got You Interested in Science? poll to draw some conclusions. Not very firm conclusions, of course, as the whole process was wildly non-scientific, and there’s no reason to expect that the respondents were a representative sample in any sense. (The numbers were not bad; the smallest category, “the internet,” received 62 votes so far.) But conclusions, nonetheless!

And the main conclusion is: there are many different things that get young proto-scientists interested in the field. Books, both non-fiction and fiction, play an important role, but no one thing really stands out.

That’s interesting, and not really what I would have expected. Given that there certainly are many things that could get someone interested in science, I wouldn’t have been surprised if there was a dominant source for the pipeline, but instead it’s quite a diverse porfolio.

If we think getting people interested in science is a good thing, the lesson is: there aren’t any magic bullets. A broad-based strategy seems appropriate. Interesting books, educational classes, encouraging relatives, engrossing hobbies and school activities, inspiring movies and TV shows. I approve.

Yesterday’s book club raised the question of what first inspires young people to get interested in science. Many Cosmic Variance readers aren’t scientists at all, but a lot of you are. So — what first set you down this road? For purposes of this highly non-scientific investigation, let’s define “scientist” fairly broadly, as someone who has either received a bachelor’s degree in some scientific field, or is currently on the road to doing so (e.g. someone currently in high school or college). Even if you’re not currently a full-time scientist, we’ll count you if you got the degree.

Here’s a poll based on my quick guesses as to what might be the leading causes of nudging people into science.

What first inspired you to study science?
	Parent, relative, or friend.
	Role model outside friends and family.
	Teacher or a particular class.
	Science fair, mathletics, or other scholastic activity.
	Personal hobby or tinkering.
	Science books (non-fiction).
	Science fiction or fantasy literature.
	Movies, TV, radio.
	The internet (for you youngsters).
	Other
Free polls from Pollhost.com

I’d be very interested to hear if I’m leaving out some hugely influential category. And you can vote for more than one thing, if you think you were influenced by multiple sources. Among the many flaws of this kind of poll is that you might not actually remember what first inspired you — maybe it was hearing something on the radio, which made you go check out a book, but you remember the book and not the radio show. So be it; just try your best to be honest.