So we’re extremely happy to note that Martin Perl (at an enthusiastic 84 years young!) has jumped into the blogosphere, with Reflections on Physics: From the Tau to Dark Energy. Perl shared the Nobel Prize in 1995 for the kind of result that every physicist dreams of achieving, but few actually do: the discovery of a new elementary particle. In particular, the tau lepton, the heaviest of the three charged leptons (along with the electron and muon). Not too shabby.

Martin’s first post is on Faster-Than-Light Neutrinos and the Dynamics of the Internet. He finds the OPERA results intriguing, but thinks that figuring them out is going to require new experiments, not clever outsiders trying to figure out where they went wrong. I would tend to trust his judgment here.

It’s fantastic to have another great physicist taking the time to reach out to a broader audience. Note that Martin is at SLAC, along with our own JoAnne and Risa. Something about the Palo Alto coffee that nudges one toward blogging?

We’ll be chatting at 9pm Eastern/6pm Pacific, at the Stella Nova Theater. If you’re not already on Second Life, it’s super easy (and free) to join. (Here’s some very useful information for beginners.) And you get to design an avatar that looks like you would want to look, rather than your inevitably-disappointing real self.

The chat is part of the Virtually Speaking series hosted by FireDogLake, in this case co-produced with the Meta Institute for Computational Astrophysics. Alan does a regular series of interviews on science, so you may get hooked. Our chat will be a multi-media extravaganza, so you can choose to listen in various ways:

• Directly in Second Life.
• Audio on BlogTalk Radio. This is an archived podcast, available on iTunes, so you can listen later if you like.
• There is also live chat on IRC. Enter #vspeak into the channel field.

Yes I know, very complicated. If simplicity is more your bag, here’s a guest video on dark energy that I did for the wonderful Minute Physics series.

This has been the summer of our numerical discontent.
As a nation, we’ve been riveted by the debates over the debt-ceiling crisis, the credit downgrade, the dizzying ascents and descents of the stock market. But how many people actually understand the numbers they’re watching?

Priya decries the general innumeracy we see everyday, writ large and small. She argues persuasively for an increased focus on math education, especially in light of the current fiscal troubles.

It is critical that the science community reach out to the general public, and opinion pieces in newspapers are an incredibly effective way to do this (blogs aren’t too shabby, either). Op-Eds allow individuals from all walks of life to communicate directly with the public, without being mediated by reporters, radio hosts, or TV producers. And they reach literally millions of people. These two terrific examples from Priya and James will hopefully help encourage other scientists to get involved, and make their opinions known.

The Sensitivity of Convection Zone Depth to Stellar Abundances: An Absolute Stellar Abundance Scale from Asteroseismology
Jennifer L. van Saders, Marc H. Pinsonneault

The base of the convection zone is a source of acoustic glitches in the asteroseismic frequency spectra of solar-like oscillators, allowing one to precisely measure the acoustic depth to the feature. We examine the sensitivity of the depth of the convection zone to mass, stellar abundances, and input physics, and in particular, the use of a measurement of the acoustic depth to the CZ as an atmosphere-independent, absolute measure of stellar metallicities. We find that for low mass stars on the main sequence with $0.4 M_{\odot} \le M \le 1.6 M_{\odot}$, the acoustic depth to the base of the convection zone, normalized by the acoustic depth to the center of the star, $\tau_{cz,n}$, is both a strong function of mass, and varies at the 0.5-1% per 0.1 dex level in [Z/X], and is therefore also a sensitive probe of the composition. We estimate the theoretical uncertainties in the stellar models, and show that combined with reasonable observational uncertainties, we can expect measure the the metallicity to within 0.15 – 0.3 dex for solar-like stars. We discuss the applications of this work to rotational mixing, particularly in the context of the observed mid F star Li dip, and to distguishing between different mixtures of heavy elements.

This example might not be immediately accessible to non-experts, but I think the idea is to pitch the video at the level of astronomy grad students. Certainly the participants deserve a lot of credit for trying out an innovative way to talk about their research.

The key to the ambition of making this a regular even is keeping it simple and easy. If it takes a couple of hours to put it together, no problem; if it takes a couple of days, enthusiasm will flag. I’m not sure what software was used to make the video and the simple graphics — iMovie, maybe? For the DNA computer video we showed some time back, it was quite an elaborate job, and you would worry that it would be onerous to do something like that for every paper one writes.

The Hawking special is the kick-off episode to a major new Discovery program, called simply Curiosity. I predict it will make something of a splash. The reason is simple: although most of the episode is about science, Hawking clearly goes all-in with “God does not exist.” It’s not a message we often hear on American TV.

The atheistic conclusion is really surprisingly explicit. I had a chance to talk to someone at Discovery, who explained a little about how the program came about. The secret is that it was originally produced by the BBC — British audiences have a different set of expectations than American ones do. My completely fictional reconstruction of the conversation would go something like this. Discovery: Hey, blokes! Do you have any programs we could use to launch our major new series? BBC: Sure, we have a new special narrated by Stephen Hawking. Discovery: Perfect! That’s always box office. What’s it about? BBC: It’s about how there is no God. Discovery: Ah.

[Update: Alas, reality is intruding upon my meant-to-be-funny imaginary dialogue. The episode was actually originally commissioned by Discovery, not by the BBC, although it was produced in the UK. More power to Discovery!]

At first, I will confess to a smidgin of annoyance that an opportunity to talk about fascinating science was being sacrificed to yet another discussion about religion. But quickly, even before anyone else had the joy of pointing it out to me, I realized how spectacularly hypocritical that was. I talk about religion all the time — why shouldn’t Stephen Hawking get the same opportunity?

The more I thought about it, the more appropriate I thought the episode really was. I can’t speak for Hawking, but I presume his interest in the topic stems from similar sources as my own. It’s not just a coincidence that we are theoretical cosmologists who happen to go around arguing that God doesn’t exist. The question of God and the questions of cosmology arise from a common impulse — to understand how the world works at its most fundamental level. These issues naturally go hand-in-hand. Pretending otherwise, I believe, probably stems from a desire on the part of religious believers to insulate their worldview from scientific critique.

Besides, people find it interesting, and rightfully so. Professional scientists are sometimes irritated by the tendency of the public to dwell on what scientists think are the “wrong” questions. Most people are fascinated by questions about God, life after death, life on other worlds, and other issues that touch on what it means to be human. These might not be fruitful research projects for most professional scientists, but part of our job should be to occasionally step back and look at the bigger picture. That’s exactly what Hawking is doing here, and more power to him. (In terms of his actual argument, I’m sympathetic to the general idea, but would take issue with some of the particulars.)

Nevertheless, Discovery was not going to feature an hour of rah-rah atheism without a spoonful of sugar to help the medicine go down. Thus, our panel discussion, which will air immediately after the debut of Curiosity (i.e., 9pm Eastern/Pacific). The four of us had fun, and I think the result will be an interesting program — and hopefully I did the side proud, as the only legit atheist participating. Gregory seemed to enjoy himself, and joked that he might have to give up politics to do a weekly show about cosmology. (A guy can dream…) But we all agreed that it was incredibly frustrating to have so little time to talk about such big issues. The show will run for half an hour; subtract commercials, and we’re left with about 21 minutes of substance. Then subtract introduction, questions, some background videos that were shown … we three panelists had about five minutes each of speaking time. Not really enough to spell out convincing answers to the major questions that have troubled thinkers for centuries. Hopefully some of the basic points came across. Let us know what you think.

Well, now Faye is tackling a new controversial (although it shouldn’t be) topic. While continuing with her regular writing, she has, over the last few months, begun writing a blog for the Inquirer on the topic of evolution. Titled Planet of the Apes, the blog features Faye’s writing paired up with illustrations from the paper’s staff editorial cartoonist, Tony Auth.

It’s a fun read, and covers current news in evolution as well as taking on some of the questions that come up when discussing the topic with those who, for whatever reason, are resistant to this established branch of scientific knowledge. Take a look at the back catalog to see some of these.

I wish Faye the best of luck with this new endeavor, and hope that we’ll see another guest post here from her soon.

I appeared on one episode of the show last year, and I’ve been on a few other science documentaries. But I don’t usually plug them ahead of time; not, as anyone who reads the blog will attest, out of any general reluctance to plug my stuff, but because you typically don’t get to see these shows before they air. And I’d just as soon not be associated with a complete piece of garbage.

But on the basis of what I’ve seen so far — last week’s episode, and several from last year — as well as talking to the show’s creators, I genuinely think that Through the Wormhole is well above the usual standard of quality one expects for these endeavors. Not that anything is perfect — there are one or two times when you’ll be thinking “how in the world did that person get interviewed here?” But there’s clearly been a lot of effort made to get the science largely right, and more importantly to take on big topics and tell something approaching a coherent story about them. Programming like this is growing thin, even on Discovery and the Science Channel, so when it appears and succeeds it should be applauded.

Also? Morgan Freeman read my book. So I at least owe him this much of a plug.

The decline effect is troubling because it reminds us how difficult it is to prove anything. We like to pretend that our experiments define the truth for us. But that’s often not the case. Just because an idea is true doesn’t mean it can be proved. And just because an idea can be proved doesn’t mean it’s true. When the experiments are done, we still have to choose what to believe.

I don’t particularly disagree with any of this. But it’s completely besides the point, and to untutored ears can be immensely misleading. The article is a perfect example of precisely the effect it seeks to describe (there must be a catchy word for this? Intellectual onomatopoeia?). The article gives a few examples of people finding interesting results, only to have them disappear on sustained scrutiny. It makes it sound like there is an epidemic of declining confidence:

One of the first demonstrations of this mysterious phenomenon came in the early nineteen-thirties. Joseph Banks Rhine, a psychologist at Duke, had developed an interest in the possibility of extrasensory perception, or E.S.P. Rhine devised an experiment featuring Zener cards, a special deck of twenty-five cards printed with one of five different symbols: a card was drawn from the deck and the subject was asked to guess the symbol. Most of Rhine’s subjects guessed about twenty per cent of the cards correctly, as you’d expect, but an undergraduate named Adam Linzmayer averaged nearly fifty per cent during his initial sessions, and pulled off several uncanny streaks, such as guessing nine cards in a row. The odds of this happening by chance are about one in two million. Linzmayer did it three times.

Rhine documented these stunning results in his notebook and prepared several papers for publication. But then, just as he began to believe in the possibility of extrasensory perception, the student lost his spooky talent. Between 1931 and 1933, Linzmayer guessed at the identity of another several thousand cards, but his success rate was now barely above chance. Rhine was forced to conclude that the student’s “extra-sensory perception ability has gone through a marked decline.”

This all sounds quite impressive. I don’t know the details of how many cards he was going through, but it sounds like it’s easily thousands. I calculate the odds of a 9 card streak as a tenth of a percent if you go through a couple of thousand cards. This is much more likely than 1 in 2 million (which is relevant only if you only look at 9 cards, one time). No doubt getting 9 in a row three times over a period of a few weeks (or even years) would be a large statistical anomaly. But it’s a long way from something I would issue a press release about. Carl Sagan summed it up best: “Extraordinary claims require extraordinary evidence”. If you’re going to claim some “extra-sensory perception” that would require a new physical force, and fundamentally alter all of modern physics, you might need more than a one-time statistical fluke. How about a whole series of controlled, double-blind experiments? Lo and behold, when this is done, the effects vanish. But by then the original results are published, and the damage is done. We’re still talking about this one “experiment” 80 years later. But if we integrate over all the equivalent subsequent experiments, there’s no doubt that the effect regressed to the mean, and can be ignored. So how is this even remotely interesting?

It takes Lehrer six pages to finally get around to the topic of publication bias. Suppose you do an experiment and find a sensational, Earth-shattering result. Human nature being what it is, you’re likely to try to publish it (and journals like Nature are likely to publicize it). Fads happen all the time in science. It’s a human activity after all. And then you (and the rest of the community) do a lot more work, and if it’s a statistical fluke, or poorly analyzed data, or a poorly conceived or biased experiment, the result will fade into oblivion. The “decline effect” that this article is making a fuss about is precisely the process by which the scientific method works. The truth will out.

On the other hand, suppose you do an experiment and find the result you (and everyone else) would expect. For example, you drop a ball and, indeed, it falls to the floor, exactly in accordance with our theory of gravity. You’re unlikely to write up the results. You’re even less likely to be able to get them published. And you’re certainly not going to spawn a whole bunch of follow-up experiments trying to duplicate your “null” results. So there’s no “incline effect”. This is not a surprise. It’s not a sign that science is broken. It’s a sign that we try to be selective and efficient in our experiments.

None of this is to say that there aren’t legitimate concerns. It’s one thing for publication bias and poor data to lead to a (temporarily) incorrect measure of the Hubble constant, and hence the age of the Universe. It’s an entirely different matter when a statistical fluke (encouraged by huge sums of money) engenders useless (or worse) medical treatment for millions of people. The only way to address this is by ever more careful and thorough application of the scientific method. (Obama’s Comparative Effectiveness Council, one of the many positive aspects of his new healthcare bill, is a good example of this.)

Lehrer’s article is a dramatic example of the problem he decries. The title and subtitle, and the first few pages, make it sound like there’s something profoundly and mysteriously wrong with the scientific method. Far into the article the obvious and rational explanations appear. Really, the article should be titled “Science works”, with a subtitle “The scientific method conquers all (eventually).” But that would be a lot less sexy, and my guess is that the New Yorker wouldn’t have published it. So there’ll be a bunch of people out there who misread or cherry-pick the article (Deepak Chopra: “Watch out, the truth is slipping away”), and end up convinced that the scientific method is broken. And they won’t vaccinate their children, and they’ll make important life decisions based on their horoscopes, and they’ll continue to believe that the world is magic. The scientific method is healthy and well. The problem is a society that, to a surprising degree, doesn’t pay much attention to it. And this article is a brilliant example of how things go wrong.

• Findings Raise New Questions About Dark Matter (redOrbit)
• Dark matter theory challenged by gassy galaxies result (BBC)
• More Evidence Against Dark Matter? (Science NOW)

Wow. More evidence against dark matter? I didn’t know about the original evidence.

Sadly (and I mean that — see below) there is no evidence against dark matter here. These items were sparked by a paper and a press release from Maryland astronomer Stacy McGaugh, with the rather more modest titles “A Novel Test of the Modified Newtonian Dynamics with Gas Rich Galaxies” and “Gas rich galaxies confirm prediction of modified gravity theory,” respectively.

I’m the first person to defend journalists against unfair attacks, and we all know that headlines are usually not written by the people who write the actual articles. But we can legitimately point fingers at a flawed system at work here: these articles are a tiny but very clear example of what is wrong wrong wrong about our current model for informing the public about science.

McGaugh’s new paper doesn’t give any evidence at all against dark matter. What it does is to claim that an alternative theory — MOND, which replaces dark matter with a modification of Newtonian dynamics — provides a good fit to a certain class of gas-rich galaxies. That’s an interesting result! Just not the result the headlines would have you believe.

It’s obvious what happens here. Nobody would read an article entitled “Gas rich galaxies confirm prediction of modified gravity theory” — or at least, most editors doubtless feel, fewer people would be interested in that than in evidence that went directly against dark matter. So let’s just spice up the story a bit by highlighting the most dramatic possible conclusion we can imagine drawing, and burying the caveats until the end. Net result: a few more people read the articles than otherwise would have, while many more people just read the headlines and are left with less understanding of modern cosmology than they started with. Scientists and journalists together have a responsibility to do a better job than this at making things clear, not just making things sound exciting.

But let me take this opportunity to lay out the problems with MOND. It’s a very clever idea, to start. In galaxies, dark matter seems to become important only when the force of gravity is not very strong. So maybe Newton’s famous inverse-square law, which tells us how the force of gravity falls off as a function of distance, needs to be modified when gravity is very weak. Miraculously, this simple idea does a really good job at accounting for the dynamics of galaxies, including — as this new result confirms — types of galaxies that weren’t yet observed back in 1983 when Mordehai Milgrom proposed the idea. Whether or not MOND is “true” as a replacement for dark matter, its phenomenological success at accounting for features of galaxies needs to be explained by whatever theory is true.

Which is an important point, because MOND is not true. That’s not an absolute statement; among its other shortcomings, MOND is not completely well-defined, so there’s a surprising amount of wriggle room available in fitting a variety of different observations. But to the vast majority of cosmologists, we have long since passed the point where MOND should be given up as a fundamental replacement for dark matter — it was a good idea that didn’t work. It happens sometimes. That’s not to say that gravity isn’t somehow modified in cosmology — you can always have very subtle effects that have yet to be discovered, and that’s a possibility well worth considering. But dark matter is real; any modification is on top of it, not instead of it.

Let’s look at the record:

• MOND is ugly. Actually, that’s very generous. More accurately, MOND is not a theory; it’s only a phenomenological rule that’s supposed to apply in a limited regime. The question is, what is the more general theory? Jacob Bekenstein, in an heroic bit of theorizing, came up with his Tensor-Vector-Scalar (TeVeS) theory, which hopefully reduces to MOND in the appropriate limits. Here is the action for general relativity:
  
  And here is the action for TeVeS:
  
  Don’t worry about what it all means; the point is that the theory underlying MOND isn’t really simple at all, it’s an ungodly concatenation of random fields interacting in highly-specific but seemingly arbitrary ways. That doesn’t mean it’s not true, but the theory certainly doesn’t win any points for elegance.
• MOND doesn’t fit clusters. Long ago, rotation curves of galaxies were the strongest evidence in favor of dark matter. Very long ago. We know better now, and a mature theory has a lot more hoops it needs to jump through. The nice thing about MOND is that, despite the ugliness above, when you get down to making predictions for large astrophysical objects, there really isn’t any wriggle room: you fit the data or you don’t. It works for galaxies, but when it comes to clusters — you don’t. Not close. Proponents of MOND understand this, of course, and they’ve come up with a clever workaround. It’s called “dark matter.” That’s right — even MOND’s biggest supporters admit that you need dark matter to explain galaxies. Let’s just emphasize that for those who find all this text kind of tedious:
  

  Even with MOND, you still need dark matter.

  Some people try to claim that the necessary dark matter could be neutrinos rather than some brand-new particle, and that’s supposed to be morally superior somehow. But there’s no two ways around the conclusion that dark matter is real.

• MOND doesn’t even fit all galaxies. For almost twenty years now we’ve known that MOND fails for a certain type of galaxies known as “dwarf spheroidals.” These are small (thus the name) and hard to observe, so MONDians have come up with various schemes to explain away particular galaxies. That might even be okay — nobody said fitting the data would always be easy, even in the correct theory — except that it’s precisely this kind of extra work that is being scoffed at in the case of dark matter in these recent news items.
• Gravity doesn’t always point in the direction of where the ordinary matter is. This is the lesson of the famous Bullet Cluster (and related observations). The evidence from gravitational lensing is absolutely unambiguous: to fit the data, you need to do better than just modifying the strength of Newtonian gravity. Once again, people try to wriggle out of this in TeVeS and other MONDian approaches. However, the way they do it is by imagining that other fields have energy, which warps spacetime, and therefore a gravitational field. We have a useful phrase to describe new fields whose energy warps spacetime: “dark matter.” MOND-like theories don’t replace dark matter so much as they make it much more complicated.
• MOND doesn’t fit the cosmic microwave background. Saving my favorite for last. One of the coolest things about the temperature anisotropies in the cosmic microwave background is that they are sensitive to the existence of dark matter. In the early universe, dark matter just collapses under the pull of gravity, while ordinary matter also feels pressure, and therefore oscillates. As a result, the two components are out of phase in the even-numbered peaks in the CMB spectrum. In English: dark matter pushes up the first and third peak in the graph below, while suppressing the second and fourth peak. That would be extremely hard to mimic in a theory without dark matter; indeed, this was predicted before the third peak was precisely measured. But now it has been. And…
  
  See that dotted line? That’s the theory with dark matter, fitting all the data. See the solid line? That’s the MOND (really TeVeS) prediction, definitively inconsistent with the data. Can some clever theorist tweak things so that there’s a MOND version that actually fits? Probably. Or we could just accept what the data are telling us.

Having said all that, I’m glad that some people are still thinking about MOND-like approaches. You can still learn interesting things about galaxies, even if you’re not discovering a new law of nature. And dark matter, to be honest, isn’t established with 100% certainty; it’s really more like 99.9% certainty, and you never know.

What’s less admirable is people (mostly outside the professional community, but not all) hanging onto a theory because they want to believe it, no matter what new information comes along. Personally, I think it would be much cooler if gravity were modified, compared to the idea that it’s just some dumb new particle out there. I’ve put some thought into the prospect myself, which helped lead to some productive research ideas. But ultimately the universe doesn’t care what I prefer. Dark matter is real — gravity could also be modified, but there’s no reasonable doubt about the dark matter. So let’s try to figure it out.

Back in 2008, Jonathan and I had for quite a while been interested in the connections between particle physics and cosmology, and in particular how experiments at current, upcoming (the LHC at that point) and future colliders could inform and be informed by modern cosmology. In fact, I’d written about these connections a number of times here on the blog, discussing, for example, the nature of WIMP dark matter, and the origin of the matter-antimatter asymmetry of the universe. And these were the starting point for our interactions with George about a SciAm article.

The journey from these initial musings to a final article was a mostly enjoyable and interesting one, and for me it contrasted greatly with the vast majority of writing that I do, presenting my own current research for journals. In those efforts, the editorial input is generally small. One receives referee reports that are hopefully mostly positive, and can sometimes (although rarely, to be honest) contain excellent suggestions that improve the final version of the paper. The editorial role is mostly in the selection of referees by a scientist serving on the editorial board, and in general grammatical editing of the paper and verification of references as it nears the publication date.

But writing for a magazine is a different experience. From the beginning it was very much a collaborative effort, with Jonathan and I honing our ideas about what should appear in the article, and George pushing some ideas and downplaying others, to fit with his experience of the kind of article that most readers want. We were all searching for the right mix of background material, new directions in the field, and connections to work that Jonathan and I had been directly involved in, and so could comment on from direct experience. Although we didn’t always agree, it was definitely a constructive process, and the final content was a consensus in the best sense of the word, with what to emphasize and what couldn’t make it into the article for space reasons (which are very tight) the outcome of lengthy, but useful negotiations between us and George. That it took a couple of years from inception to publication is partly a reflection of the natural time it takes for a lot of back and forth between editor and authors who have busy day jobs, and partly because in the middle I moved institutions, putting me out of action for a while.

What we ended up focusing on is the intriguing possibility that the dark sector of cosmology might exhibit a considerably richer structure than our usual simple descriptions of a plain WIMP candidate for dark matter, and a cosmological constant, or sequestered dark energy component driving cosmic acceleration. Rather, it is possible that the dark sector contains it’s own set of new particles and forces, and that our detections, gravitationally based so far, have not yet been able to probe this underlying structure. We wrote about interesting possibilities for dark matter, some of which are related to work Jonathan has done, for much of the article, and at the end turned to the possibility of interactions with dark energy, which I’ve worked on and have occasionally written about here. As we concluded the article:

The only matter we know anything about, visible matter, comprises a rich spectrum of particles with multiple interactions determined by beautiful underlying symmetry principles. Nothing suggests that dark matter and dark energy should be any different. We may not encounter dark stars, planets and people, but just as we could hardly imagine the solar system without Neptune, Pluto and the swarm of objects that lie even farther out, one day we might not be able to conceive of a universe without an intricate and fascinating dark world.

The article isn’t perfect, of course. For example, there is a heading for one of the figures that reads “Experiments that claim to have detected dark matter”. We didn’t write that, but we should have caught it in proofs. It is wrong, of course, and should read something like “Experiments that are searching for dark matter”. Also, after being so close to the material for a while, there are some ambiguities that you don’t notice unless someone else reads them a different way and lets you know. But in all, I think Jonathan and I are pretty happy with the final article.

For me, it was an enjoyable experience, with several highlights. First and foremost, we had an engaged and sympathetic editor who understood both the science and the target audience. Thanks George! Second, it is wonderful fun to receive some actual draft page proofs, after months of exchanging a visually unappealing text file, and to see the art work that has been designed to accompany the article. We had some very rough ideas regarding one or two of the figures, but most of the visual parts of the article were created with no initial input from us. We helped tweak at the end, and certainly helped with text in the figures, but the gorgeous graphics were essentially all the magazine’s work. And finally, George never even hinted to us, but when we received copies of the actual magazine a few days before it appeared, we were shocked and delighted to see that our article was the cover article. I can’t tell you how thrilled my mother will be!

Just like the newsstand version, the online version of the article costs money of course. But if you do read it, I hope you enjoy it.

Sadly the deadline is passed, so we can’t encourage you to contribute, but you can check out the entries. Here’s a video about the LHC, by Luke Cahill. (I’m using YouTube’s new “iframe” embedding scheme; let me know if it doesn’t work.)

Here’s an excerpt from a map of the emotions by Emanuel Derman, based on Spinoza’s Ethics. I zoomed in on the cluster centered around pain, because that’s what people will be drawn to first anyway.

He said vs. She said,

then the job of a journalist is not to take sides. But there’s another possible dichotomy that is much more crucial:

Truth vs. Falsity.

In this case, it’s equally clear that journalists should take sides: they should be in favor of the truth. Not just passively, by trying not to make things up, but actively, by trying to figure out whether something is false before reporting it, even if it’s been said by someone.

All sounds kind of trivial, but it’s easy to lose sight of this principle by hewing to a misguided definition of “objectivity.” Ed pulls an extremely damning quote from medical journalist Jeremy Laurance:

Reporters are messengers – their job is to tell, as accurately as they can, what has been said, with the benefit of such insight as their experience allows them to bring, not to second guess whether what is said is right.

That sounds about as wrong as it it possible to be wrong. It reflects a kind of lazy pseudo-objectivity that stems mostly, I would uncharitably suggest, from fear — the fear that one will make a mistake in trying to judge whether someone is lying or telling the truth. If journalists are just mindless stenographers, they can’t be accused of making that particular mistake. But they are actually making a much more serious mistake, abandoning the search for truth in favor of the goal of not being blamed.

It’s hard to argue against this mindset, which is often mis-labeled as “objectivity.” So maybe we should be defending the New Objectivity: the crucial duty of reporters to separate what is true from what is false. If a scientist says “this drug will cure cancer,” but the peer-review study doesn’t back that up, it should be a journalist’s duty to make that clear. If a politician says “my plan will cut the deficit,” but a GAO report suggests otherwise, it should be a journalist’s duty to highlight the inconsistency. “Objectivity” shouldn’t mean “report what is said and don’t pass judgment”; it means “uncover the truth, no matter who says what.”

There is a lesson here, in the reaction to the title The Calculus Diaries. You write a book to emphasize the fun and conceptual side of math, to reach an audience that doesn’t traditionally pick up science books. How do you get them to buy a book with “Calculus” in the title? Zombies and Vegas help, but it’s an uphill battle.

Yes, you read that subtitle correctly. Let’s be clear: this book is probably not for you. That’s because you, I have no doubt, already love calculus. You carry a table of integrals in your back pocket, and you practice substituting variables to while away the time in the DMV. This isn’t the book for people who already appreciate the austere beauty of a differential equation, or even for people who want to study up for their AP exam.

No, this is the book for people who hate math. It’s for people who look at you funny and turn away at parties when you mention that you enjoy science. It’s for your older relatives who think you’re crazy for appreciating all that technical stuff, or your nieces and nephews who haven’t yet been captivated by the beauty of mathematics. The Calculus Diaries is the book for people who need to be convinced that math isn’t an intimidating chore — that it can be fun.

Know anybody like that? Any gift-giving holidays coming up?

Now it’s true, I know the author. In fact, I appear as a character in the book (to a certain degree of comic effect). I’m the one who gets soaked when we ride Splash Mountain at Disneyland, but also the one who maximizes his winnings at craps by clever betting in Vegas. You get the idea: this isn’t a textbook, it’s a tour through the real world (and occasional fantasy worlds), pointing out that math is all around us, and that perceiving it is kind of cool.

When you understand math, how you think about the world changes. Every day, we all change position by accumulating velocity, or do informal optimization problems when making a decision. But most people don’t know about the wonderful insights that math can add to these processes. You know, because you are a mathphile. But you are outnumbered by the mathphobes. You have a secret that they don’t know, but now there’s a way to share it. What are you waiting for?

It will be a lot like Armageddon, with Phil instead of Bruce Willis in the role of the balding hero figure. And science instead of complete nonsense. Improvements all around!

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.

Not so awesome at all, actually, but it did happen. I much prefer a low-drama lifestyle, and it takes a certain kind of talent to get me that annoyed. Nothing to be proud of; I should have been more careful in learning what the show was about in the first place.

The backstory is that I was called on the phone by producers at a company I had never heard of, but that means nothing, as I haven’t heard of the vast majority of TV production companies. [Update: name of the company removed because I signed a non-disclosure agreement. They didn't complain, just being cautious.] They wanted to come to campus to interview me for a pilot they were producing. I’ve done the drill before, for respectable outlets like the History Channel, Science Channel, and National Geographic. It’s a couple of hours of work, no heavy lifting, and hopefully you get to explain some cool science that will be seen by a much larger audience than I could possibly reach by giving a thousand public lectures. And it’s fun — I get to be on TV, which growing up wasn’t the kind of thing I ever thought I’d get to do.

They explained that they wanted me to talk about quantum teleportation. I countered by mentioning that there were surely better experts that they could talk to. But they really just needed some background information about quantum mechanics and relativity, and were comforted by the fact I had appeared on camera before. And the producer emphasized that they knew perfectly well that teleportation wasn’t realistic right now, but thought it was interesting to speculate about what might ultimately be consistent with the laws of physics. So I agreed. There was a slight hint of sketchiness about the operation — they seemed to be unable to come to an agreement with Caltech in regards to consent forms, which National Geographic or the History Channel never had trouble with. But my antennae weren’t sensitive enough to set off any alarm bells.

So the taping was this afternoon, and it consisted of me chatting informally with the show’s two hosts, while taking a leisurely walk around Caltech’s quite lovely campus. But as soon as we started talking, things went rapidly downhill. The first question was what I thought about claims that people had actually built successful teleportation devices. When I expressed skepticism, one of the hosts challenged me by asking whether I would just be repeating the “party line” of the scientific establishment. I admitted that I probably would, as I think the party line is mostly right. And that we have very good reasons for thinking so.

They next asked whether it wasn’t possible that people had built teleporters by taking advantage of extra dimensions. I explained why this wasn’t possible — extra dimensions are things that physicists take very seriously, but if they are macroscopically accessible they would have shown up in experiments long ago. From there, the downhill spiral just continued. They asked whether I was familiar with the “black projects” conducted by the CIA and the military? What about eyewitness testimony of people who had been to Mars and back? Was it possible that ghosts and/or extraterrestrials used quantum mechanics to travel through walls?

It sounds even worse in retrospect than it did at the time, because they would intersperse the craziness with relatively straightforward questions about physics. But I think that even the straightforward questions were just an accident — they were trying to be goofy, but didn’t understand the difference between what is possible and what is just crazy. (“Do you think it’s possible to travel into the future at a faster rate than normal?”) The producer would occasionally interrupt with some sort of suggestion that they actually say something about quantum teleportation. “I don’t really know anything about that,” replied the host to which I was speaking.

Eventually one of the hosts mentioned psychic remote viewing, and smirked when I tried to explain that it’s easier to disbelieve a few eyewitness reports than to imagine a complete breakdown of the laws of physics. With that, after having resisted the temptation for a good fifteen minutes, I cut it off and walked away. The producers tried to get me to come back, but there was no way. I don’t know whether they will go ahead and use any of the footage from my interview; I don’t think I said anything I would later regret, but I did sign a consent form. Hopefully they will try to salvage a shred of their own respectability, and not use me on the show.

The problem for me wasn’t primarily the credulous attitude toward craziness — although there was that. The real problem was dishonesty. In their last-ditch effort to get me to come back, the producers tried to explain that they really were interested in quantum teleportation, and the hosts had simply wandered off-script. The show wouldn’t be biased in favor of the paranormal, they assured me. The problem is, nowhere in talking to me about the show was the word “paranormal” ever mentioned. I was given the impression that it was a straightforward science show, and that was simply untrue.

There is a perfectly reasonable debate to be had, concerning the extent to which respectable scientists should publicly engage with pseudoscientific craziness. Under the right circumstances I could conceivably be willing to participate in a show that discussed paranormal phenomena, as long as I could be convinced that it was done in a sensible way and my views would be fairly represented. This was nothing like that — all of my pre-interview communication with the producers was strictly about quantum mechanics and teleportation, with no mention of pseudoscience at all. Once the cameras started rolling, it was all ghosts and remote viewing. Completely unprofessional; hopefully next time I’ll be more careful.

Also, for future reference: no brown M&M’s in the green room!

And yes there is a video record of the whole event! (And other Discover videos.)

The rough idea was to point out examples of good and bad science in science fiction on movies and TV. Phil scored the best example of bad science, finding a brief clip from Armageddon where Bruce Willis is doing delicate work on the surface of an asteroid — in the rain. Jaime and Zack, who actually work in Hollywood, wisely foresaw the pitfalls of holding up someone else’s stuff as an example of badness, and graciously both chose examples from their own work. Sometimes the science must take a backseat to the story.

But not usually. In my own presentation I tried to move beyond the model of scientist as copy-editor, running through stories and films looking for violations of the laws of physics, wagging the finger of shame with ill-concealed glee. I think scientists should take a more creative role, helping fiction writers to develop consistent rules for their fictional worlds and extrapolating the consequences of those worlds, even if those rules are not the rules of our real universe. We should be more than scolds.

Update: since the two clips I showed were apparently missing from the video, I’m linking to them here. The first was a forward-looking philosophy of the proper relationship between science and narrative, and the second was an example of carefully exploring the logical consequences of an imaginary world.

With that in mind: check out this story by Sharon Begley from Newsweek, on how media are slowly backing away from the Climategate hysteria. (Via PZ.) She very rightly highlights the real damage: the backing-away won’t undo all the misimpressions of scientific malfeasance that people absorbed when the story was at its height.