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On occasion, somebody voices the idea that in year [tex]N[/tex], physicists thought they had everything basically figured out, and that all they had to do was compute more decimal digits. I won’t pretend to know whether this is actually true for any values of [tex]N[/tex] — when did one old man’s grumpiness become the definitive statement about a scientific age? — but it’s interesting that not every physicist with an interest in history has supported the claim.

One classic illustration of how the old guys with the beards knew their understanding of physics was incomplete involves the specific heats of gases. How much does a gas warm up when a given amount of energy is poured into it? The physics of the 1890s was unable to resolve this problem. The solution, achieved in the next century, required quantum mechanics, but the problem was far from unknown in the years before 1900. Quoting Richard Feynman’s Lectures on Physics (1964), volume 1, chapter 40, with hyperlinks added by me:
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…to the most thoroughly awesome movie ever.

I’m seriously proud of this one:

The Merry May Incident.

(Filed under EXT. CITY – NIGHT.)

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The Faculty of 1000 recently announced a competition for the best made-up drug name, and my contribution is one of the three finalists. The winner will be chosen through the supremely scientific methodology of the Interweb Poll. I encourage the Gentle Reader to visit, chuckle and vote your conscience.

UPDATE (5 August): Hey, I won! Thanks everybody! Now the swag is mine, all mine, moo hoo ha ha, etc.

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Why? Solidarity.

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In network science, one can study the dynamics of a network — nodes being added or removed, edges being rewired — or the dynamics on the network — spins flipping from up to down in an Ising model, traffic flow along subway routes, an infection spreading through a susceptible population, etc. These have often been studied separately, on the rationale that they occur at different timescales. For example, the traffic load on the different lines of the Boston subway network changes on an hourly basis, but the plans to extend the Green Line into Medford have been deliberated since World War II.

In the past few years, increasing attention has been focused on adaptive networks, in which the dynamics of and the dynamics on can occur at comparable timescales and feed back on one another. Useful references:
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I appear to be live-tweeting the International Conference on Complex Systems, using the hashtag #iccs11.

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A few complaints about the place of computers in physics classrooms.

Every once in a while, I see an enthusiastic discussion somewhere on the Intertubes about bringing new technological toys into physics classrooms. Instead of having one professor lecture at a room of unengaged, unresponsive bodies, why not put tools into the students’ hands and create a new environment full of interactivity and feedback? Put generically like that, it does sound intriguing, and new digital toys are always shiny, aren’t they?

Prototypical among these schemes is MIT’s “Technology Enabled Active Learning” (traditionally and henceforth TEAL), which, again, you’d think I’d love for the whole alma mater patriotism thing. (“Bright college days, O carefree days that fly…”) I went through introductory physics at MIT a few years too early to get the TEAL deal (I didn’t have Walter Lewin as a professor, either, as it happens). For myself, I couldn’t see the point of buying all those computers and then using them in ways which did not reflect the ways working physicists actually use computers. Watching animations? Answering multiple-choice questions? Where was the model-building, the hypothesis-testing through numerical investigation? In 1963, Feynman was able to explain to Caltech undergraduates how one used a numerical simulation to get predictions out of a hypothesis when one didn’t know the advanced mathematics necessary to do so by hand, or if nobody had yet developed the mathematics in question. Surely, forty years and umpteen revolutions in computer technology later, we wouldn’t be moving backward, would we?

Everything I heard about TEAL from the students younger than I — every statement without exception, mind — was that it was a dreadful experience, technological glitz with no substance. Now, I’ll freely admit there was probably a heckuva sampling bias involved here: the people I had a chance to speak with about TEAL were, by and large, other physics majors. That is, they were the ones who survived the first-year classes and dove on in to the rest of the programme. So, (a) one would expect they had a more solid grasp of the essential concepts covered in the first year, all else being equal, and (b) they may have had more prior interest and experience with physics than students who declared other majors. But, if the students who liked physics the most and were the best at it couldn’t find a single good thing to say about TEAL, then TEAL needed work.

If your wonderful new education scheme makes things somewhat better for an “average” student but also makes them significantly worse for a sizeable fraction of students, you’re doing something wrong. The map is not the territory, and the average is not the population.

It’s easy to dismiss such complaints. Here, let me give you a running start: “Those kids are just too accustomed to lectures. They find lecture classes fun, so fun they’re fooled into thinking they’re learning.” (We knew dull lecturers when we had them.) “Look at the improvement in attendance rates!” (Not the most controlled of experiments. At a university where everyone has far too many demands made of their time and absolutely no one can fit everything they ought to do into a day, you learn to slack where you can. If attendance is mandated in one spot, it’ll suffer elsewhere.)

Or, perhaps, one could take the fact that physics majors at MIT loathed the entire TEAL experience as a sign that what TEAL did was not the best for every student involved. If interactivity within the classroom is such a wonderful thing, then is it so hard to wonder if interactivity at a larger scale, at the curricular level, might be advisable, too?

It’s not just a matter of doing one thing for the serious physics enthusiasts and another for the non-majors (to use a scandalously pejorative term).

What I had expected the Technological Enabling of Active Learning to look like is actually more like another project from MIT, StarLogo. Unfortunately, the efforts to build science curricula with StarLogo have been going on mostly at the middle- and high-school level. Their accomplishments and philosophy have not been applied to filling the gaps or shoring up the weak spots in MIT’s own curricula. For example, statistical techniques for data analysis aren’t taught to physics majors until junior year, and then they’re stuffed into Junior Lab, one of the most demanding courses offered at the Institute. To recycle part of an earlier rant:

Now, there’s a great deal to be said for stress-testing your students (putting them through Degree Absolute, as it were). The real problem was that it was hard for all the wrong reasons. Not only were the experiments tricky and the concepts on which they were based abstruse, but also we students had to pick up a variety of skills we’d never needed before, none of them connected to any particular experiment but all of them necessary to get the overall job done. What’s more, all these skills required becoming competent and comfortable with one or more technological tools, mostly of the software persuasion. For example: we had to pick up statistical data analysis, curve fitting and all that pretty much by osmosis: “Here’s a MATLAB script, kids — have at it!” This is the sort of poor training which leads to sinful behaviour on log-log plots in later life. Likewise, we’d never had to write up an experiment in formal journal style, or give a technical presentation. (The few experiences with laboratory work provided in freshman and sophomore years were, to put it simply, a joke.) All this on top of the scientific theory and experimental methods we were ostensibly learning!

Sure, it’s great to throw the kids in the pool to force them to swim, but the water is deep enough already! To my way of thinking, it would make more sense to offload those accessory skills like data description, simulation-building, technical writing and oral presentation to an earlier class, where the scientific content being presented is easier. Own up to the fact that you’re the most intimidating major at an elite technical university: make the sophomore-year classes a little tougher, and junior year can remain just as rough, but be so in a more useful way. We might as well go insane and start hallucinating for the right reason.

Better yet, we might end up teaching these skills to a larger fraction of the students who need them. Why should education from which all scientists could benefit be the exclusive province of experimental physicists? I haven’t the foggiest idea. We have all these topics which ought to go into first- or second-year classes — everyone needs them, they don’t require advanced knowledge in physics itself — but the ways we’ve chosen to rework those introductory classes aren’t helping.

To put it another way: if you’re taking “freshman physics for non-majors,” which will you use more often in life: Lenz’s Law or the concept of an error bar?

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Am I the only nerd out there who doesn’t really give a pair of fetid dingo’s kidneys for logic puzzles? The blue-eyed islanders always tell the truth, except on Thursdays after teatime, when they put on the mauve hats and can only smoke Parliaments if the fox and the cabbage are left on the island simultaneously . . . If I wanted to fret about the behaviour of agents whose actions and character are unlike actual humans in every way, I’d be an economist.

(Also, I never made it further into Tolkien than The Hobbit, and my closest approach to superhero comics has been Sandman. Everything I know of RPGs I learned because I had a flatmate once who spent her evenings whacking things with a Keyblade. For a costweeting physicist, I have a surprising level of indifference to vast stretches of “geek canon” — as the Internets seem to define it. Maybe the notion of “canon” doesn’t mesh so well with the idea of a personality geared to intense interest in particular, more-or-less circumscribed subjects?)

If your logic puzzle ties into some larger body of mathematics, then I might be able to summon up interest in it, but in my experience, they’re seldom presented that way. When a puzzle has no connection to the larger weave of knowledge, to an actual -ology either pure or applied, I move on to ones which do.

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We are currently in the midst of updating the too-long-unupdated software which underlies Science After Sunclipse. This process has largely gone without incident, though some mathematical formulæ are failing to display properly. Until we get everything sorted, just imagine an early-1990s “This Website Under Construction” icon next to anything which doesn’t look right.

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Consider the Lagrangian density

\[ \mathcal{L} (\tilde{\phi},\phi) = \tilde{\phi}\left((\partial_t + D_A(r_A - \nabla^2)\right)\phi - u\tilde{\phi}(\tilde{\phi} - \phi)\phi + \tau \tilde{\phi}^2\phi^2. \]

Particle physicists of the 1970s would recognize this as the Lagrangian for a Reggeon field theory with triple- and quadruple-Pomeron interaction vertices. In the modern literature on theoretical ecology, it encodes the behaviour of a spatially distributed predator-prey system near the predator extinction threshold.

Such is the perplexing unity of mathematical science: formula X appears in widely separated fields A and Z. Sometimes, this is a sign that a common effect is at work in the phenomena of A and those of Z; or, it could just mean that scientists couldn’t think of anything new and kept doing whatever worked the first time. Wisdom lies in knowing which is the case on any particular day.

[Reposted from the archives, in the light of John Baez's recent writings.]

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For your convenience:

The following is a list of debunkings of Stephen C. Meyer’s Signature in the Cell, arranged more or less in chronological order. I have not included every blog post I’ve seen on the topic; as I did for Behe’s The Edge of Evolution, I’ve focused on the most substantive remarks, rather than keeping track of every time somebody just quoted somebody else. (I’ve also probably overlooked, forgotten, mistakenly thought I’d already included or never been made aware of some worthwhile essays.) In some cases, additional relevant posts can be found by following links within the essays I have listed.
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The 2010 edition of The Open Laboratory, the annual anthology of science blogging, is now available for purchase, as a handsome print volume or a PDF compatible with e-reader devices. Proceeds from book sales go to funding the ScienceOnline 2012 conference, which is currently in the planning stage.

Eventually, I’ll find/make the time to write about how we make blog posts into a book. First, Series Editor Bora Zivkovic chooses the guest editor for the year. Then, the two of them contact me and tell me it’s time to take the LaTeX templates out of their ceremonial encasements. Next, I draw a transmutation circle and start looking for sacrifices. . . .

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In the wake of ScienceOnline2011, at which the two sessions I co-moderated went pleasingly well, my Blogohedron-related time and energy has largely gone to doing the LaTeXnical work for this year’s Open Laboratory anthology. I have also made a few small contributions to the Azimuth Project, including a Python implementation of a stochastic Hopf bifurcation model.

I continue to fall behind in writing the book reviews I have promised (to myself, if to nobody else). At ScienceOnline, I scored a free copy of Greg Gbur’s new textbook, Mathematical Methods for Optical Physics and Engineering. Truth be told, at the book-and-author shindig where they had the books written by people attending the conference all laid out and wrapped in anonymizing brown paper, I gauged which one had the proper size and weight for a mathematical-methods textbook and snarfed that. On the logic, you see, that if anyone who was not a physics person drew that book from the pile, they’d probably be sad. (The textbook author was somewhat complicit in this plan.) I am happy to report that I’ve found it a good textbook; it should be useful for advanced undergraduates, procrastinating graduate students and those seeking a clear introduction to techniques used in optics but not commonly addressed in broad-spectrum mathematical-methods books.

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Merry Christmas, everyone.

To our thinking, Reader, it was a sorrowful star, that star of Bethlehem. What good purpose for Jesus or for anyone it served we cannot discover. It stood over Bethlehem, however, with a dire meaning to the homes there. All the little children there, except the one that “fled” into Africa were soon to be little corpses. The star of Bethlehem has had some little tolerable poetry and a great deal of doggerel addressed to it; also a considerable quantity of religious and sentimental prose. It has, too, had a good deal of banter bestowed upon it, which yields less amusement however, than the laborious effort of some theologians to throw light upon it by semi-natural conjectures as to how it may have been produced. They seem to have been led into these ill-advised attempts to naturalize the Magi’s light from its being termed a star; forgetful of the fact that the Jews who did not know what or where the real stars are, but thought them to be little ornaments to our earth, would very naturally give that name to such an appearance.

[...]

There were, so it seems to us mortals, two ways open to Providence of shielding Jesus from harm. First, by staying the arm of Herod, and thus saving not only the life of Jesus, but also the lives of all his fellow little towns-children; or, as here given, flight on the part of the holy family, and abandonment, sauve que peut, for all the other little Bethlehemites. We are grieved to find that Providence chose the latter. And as we read this, we are compelled to say that our heart is not with the fugitives into Egypt, but entirely with the little victims and their parents thus left behind.

[...]

The visit of the Magi to Jerusalem proved to be a most calamitous occurrence. Their declaration in Jerusalem that a King of the Jews was just born excited Herod’s attention; led to the flight of Jesus and his parents from the country; and, worst of all, led to the dreadful massacre our author now proceeds to narrate. What useful, what conceivable purpose was served by this untoward announcement on the part of the Magi, is not discoverable. Jesus, for at least thirty years afterwards lived in seclusion up in Galilee, his very existence unknown in Jerusalem. And when he went there towards the end of his life, we shall look in vain for the slightest reference either by himself or by anyone else to what we here read. Anything more utterly purposeless than this visit to Jerusalem of the Magi and its pitiable consequences it would be difficult to imagine.

[...]

Were we told that Herod overtook these mischievous Magi and slaughtered them also, we think few readers would feel very much more grieved.

The first Christmas was not a festive one in Bethlehem. There was “lamentation and weeping and great mourning” there. Poor Bethlehem! The journey of Joseph and Mary from Nazareth for the special purpose that Jesus might be born in Bethlehem may have been an honour, but it was dearly bought.

[...]

With the amiable view, we suppose, of softening our pain at the narrative of this massacre, and its permission in such a connection, some commentators have ventured to offer us some considerations, intended, we gather, to be soothing to our hearts if not to our minds. These little victims were in reality favoured beings, we are told; they are now termed “the holy innocents,” though why more holy or more innocent than any other children dying young is not stated; they were by this means saved from the ills and trials of life; and they are now safely lodged in Heaven. Some doubt, however, seems to exist as to whether they continue babes in that happy land or no. We do not know what warrant there is for such assertions, nor do we know whether these commentators would like their own children to be favoured in a like way. From such a point of view it almost seems a matter of regret that the radius of the slaughter was not greatly extended. We know nothing in the world more truly sad than the wild arguments used by pious men in struggling with the ugly parts of their holy writ. For ourselves, we find a much more solid comfort as we think of this melancholy story. It is that it rests on the sole unsupported statement of our author. Of corroboration there is not a vestige. Learned Christian scholars have toiled zealously, not, as one might have hoped, to dispel this story, but we regret to say, to substantiate it. We are thankful to add without any success whatever.

From pages 12 ff. of A Plain Commentary on the First Gospel by an Agnostic, Williams and Norgate, 1891. http://books.google.com/books?id=cXpCAAAAIAAJ.

Goodnight, children, everywhere.

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Odd as it may seem, I have received several e-mails lately inquiring about these subjects; so, I’ve decided to set down my positions.

1. I have no desire to run ads on Science After Sunclipse. The son of two journalists, I believe in keeping a firewall between editorial and advertising, and this site is my editorial space. I am not so poor that I cannot afford the smidgen of hosting which a low-key site like mine requires. If I promote anything with profit in mind, it’ll be something which is as much mine as this site is.

2. I am not likely to run “guest posts” by people I’ve never met. This is a matter of practicality more than of principle. My experience with blog collectives has been that they bring more drama than I find genial; likewise, being an active Wikipedia editor is not an effort I’d like to repeat. Involving other people in this notebook of mine, unless I already know them personally, is a hassle I’m happy to avoid.

There. That’s that sorted.

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Christopher Maloney is a quack who just keeps on quacking.

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