I opened the New Yorker a couple of weeks ago to find a feature piece written by Jennifer Kahn, a friend of mine from college. The New Yorker has good taste. Jenn was a fellow physics undergraduate major, but at graduation decided to pursue a career in science journalism. This seems much more challenging than physics; there is no clear career path, supporting oneself financially is a constant struggle, and success is often ill-defined and elusive. But Jenn has succeeded. She is a contributing editor at Wired and a teaching fellow at the Berkeley Graduate School of Journalism. She has published in a wide range of magazines, and has had four articles selected for the annual “Best American Science Writing” series. This is her second feature article for the New Yorker (her previous was on the 9/11 syndrome).

Her article is on Dathan Ritzenhein, a marathoner trying to recapture his glory days. He is being coached by Alberto Salazar, “regarded by many as the best American marathoner ever.” The trick is that Salazar is trying to reinvent the way Ritzenhein runs. And, most interestingly, the approach is to apply science and technology, rather than simply blunt training and fitness, to perfect the athlete. Jenn tells us:

The fastest finishers had a higher thigh drive, for one thing; at its apex, their femur bone was almost parallel to the ground, like the front legs of a bounding deer. They also slapped the ground so quickly with their forefoot that the contact seemed almost incidental. According to Walker, the short slap transfers force more efficiently, shooting it from the ground forward into the pelvis, rather than allowing it to dissipate in the flex of the foot. The effect, Walker says, is like “a pogo stick with a stiff spring.” He explained, “You want the chain of force to travel from the ground through the body with minimal energy loss. That’s what it means to run efficiently.”

I’m not sure any equations are involved, but the basic idea of applying science directly to biomechanics makes sense. The novelty is that it’s not just making a slipperier swim suit or a faster sneaker, but rather it’s an attempt to engineer a whole new way for the body to move.

The story came out the week of the New York Marathon. We now have the benefit of hindsight. Ritzenhein placed eighth, over four minutes behind the top finishers (but still at an unbelievable 2:12:33; I couldn’t keep up for even half a mile, much less all 26+). I guess physics can only do so much.

David Reffkin is a radio host at KUSF in San Francisco. His usual gig is classical music, but once a month he hosts a special called Static Limit where he delves into physics and cosmology. Here’s an interview he did with me a short while back. Right at the beginning we’re talking about this very blog, which I am now using to plug the interview, which is mostly about my book. This is what’s known as “synergy.”

(Those viewing in an RSS reader, you have to visit the page to click the audio link.)

David assumes the listeners have been following along previous shows, so we don’t spend too much time defining general relativity and the Big Bang; we go right for the cutting edge. But we also covered a lot of meta ground, about the process of doing physics. He also gave me the most comprehensive list of errata (mostly minor typos) for my book, so I know he read the whole thing!

If I ever give up blogging for good, it will be because of comments like this:

I just don’t get it. What a lame blog topic that should have been left on the cutting room floor. There is no science here. Evidently cited just to provide an opportunity to express a personal belief. Why not blog on the news of the day..the successfully trapping the first “anti-atom” and its potential implications? This is real news, real science and in keeping with your expertise. You could teach me something. Instead you give me this?

Obviously the sensible reaction is to laugh and move on, but few of us achieve that level of Zen detachment in dealing with the world. Many of the comments at CV are great, and I’ve certainly learned a lot from the interactions here, but quite a high percentage are of this form. When you put a lot of work into the blog and care about how it turns out, this kind of stuff wears you down. Why are people like this? I understand that not every post will interest every person; is it really more satisfying to take time to lash out in the comment section (when you have never left a constructive comment yet), rather than just skipping to something else on the vast and endlessly amusing internet?

[/grumpy]

Earlier today I learned of the passing of Allan Sandage. Allan was a tremendously broad astronomer, who had a lasting impact on fields of astronomy stretching from stellar evolution to the largest cosmological issues. He is perhaps best known for his work on the distance scale, and measurements of the Hubble Constant, but he had equally significant contributions to our understanding of stars.

The prominence of his work on the Hubble Constant is in part due to the rather contentious history of this subject over much of the 90′s and early 2000′s. Allan was at heart a stellar astronomer, but one who found himself tied to Hubble’s legacy by virtue of being Hubble’s telescope assistant in the years leading up to Hubble’s unexpected death in 1953. As one of the earliest pioneers (with Martin Schwarzschild) of the technique of using main sequence turnoffs to assign ages to globular clusters, Allan was deeply (and understandably) bothered by experiments that returned large values of the Hubble Constant — these values implied ages for the universe that were younger than the oldest globular clusters, which was clearly an implausible contradiction. Instead, Allan and his collaborators published a long series of papers attempting to deal will every uncertainty and bias in the distance scale, and found a consistently smaller value of the Hubble Constant than the other competing team (the “Hubble Key Project”, led by Wendy Freedman with many collaborators). In time, Allan’s group’s on-going evaluations of the distance calibration gradually pushed their value of the Hubble Constant up somewhat, while the Key Project’s values were being nudged down a bit (although they never did actually meet, particularly as error bars shrank in more recent years). Simultaneously, the discovery of dark energy changed the age estimates for the universe, allowing old globular clusters to co-exist harmoniously with a moderate value of the Hubble Constant.

During this time, Allan developed a reputation for being, well, difficult. His scientific disagreements on this issue unfortunately veered occasionally into the personal. That said, I had the pleasure of being a postdoc at the Carnegie Observatories during this time, and had an office a few doors down the hall from him. Allan was invariably gracious and kind to the postdocs. He was scientifically engaged, and always willing to share his knowledge, which was both deep and wide. I enjoyed having him for a colleague for 4 years, during a very scientifically vibrant stage of my astronomical training, and I am very sorry to hear of his passing.

Not too early to be drawing up Christmas gift lists, is it? (Or Newton’s birthday gift lists, if that’s how you roll.) Do I have the perfect suggestion for you: a nice copy of From Eternity to Here, undoubtedly the best book about the nature of time written by a Discover blogger this year. And the paperback has just been released today, so you get just as much knowledge for a fraction of the cost! Take your pick from Amazon, Barnes & Noble, Borders, or Indiebound. (But it’s always nice, as an author, to get a big boost in the Amazon rankings. Just saying.)

We should celebrate with a contest or something — I have a few copies of the paperback that could be given away, but no clever ideas to spark a competition. Best short story about the arrow of time? Limericks are out, but perhaps sonnets? Or just for the biggest contributors to our Donors Choose campaign? Suggestions welcome. (Best suggestion for a contest? How deliciously meta.)

At the moment Amazon is offering a bargain price on the hardcover, even cheaper than the paperback (presumably to clear out inventory). They are also pushing their Kindle editions, presumably to help stave off the iPad onslaught. Truth is, there are a lot more books available for Kindle than in the iBooks store, so like many people I read books on my iPad using the Kindle app.

Anyway, Amazon is allowing readers to peruse the first chapters of some of their Kindle books — so here you go! I wish it had been the second chapter, to be honest; that is where we get into some of the mysteries of entropy and the arrow of time. Chapter One is a bit more scene-setting (but it’s a pretty awesome scene).

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John Huchra, a leading astronomer at the Harvard-Smithsonian Center for Astrophysics, passed away on Friday. I’m not sure of the cause, but he had been suffering from heart problems; he was 61 years old.

John was most obviously known for his scientific accomplishments, especially as a guiding force behind the CfA Redshift Survey. For you youngsters out there, this project was the pioneering effort at mapping the large-scale structure of the universe. It revealed, to the surprise of many, that there was a lot of structure out there! The iconic image of cosmology in the 1980′s was the “CfA Stickman” reveal in the famous A Slice of the Universe paper by Valerie de Lapparent, Margaret Geller, and Huchra.

The stickman was not the universe being playfully anthropomorphic, it was simply the Coma cluster as distorted in redshift space. (You measure positions on the sphere of the sky, but velocities along the line of sight; converting these velocities to distances is inevitably distorted because galaxies in a cluster have peculiar motions inside the cluster.) Before this map was released in 1986, many people assumed that the galaxy distribution would be basically uniform on these scales. They shouldn’t have thought that, in retrospect (you need to go to larger scales before the uniformity becomes apparent), but sometimes it takes real data to get a point across. The survey went on to discover the Great Wall of galaxies, arguably the largest known “object” in the universe.

John had a number of other important contributions, including measurements of the Hubble constant and the discovery of Huchra’s Lens, one of the most dramatic early examples of gravitational lensing. He was also very active in the community, serving as president of the American Astronomical Society and numerous other roles.

But many of us will remember him mostly for his spirit and good humor. When I was a graduate student at CfA, he was one of the most friendly and helpful senior faculty members around, someone you were always happy to bump into in the hallways. There is a guestbook here for people to leave their reminiscences about John; he will be greatly missed.

Okay, I think it’s time to step down from hiatus and get back into this blogging thing. I missed you guys! And I notice that the science blogosphere has completely blown up and re-organized since I left. Which is a good thing.

I don’t like to navel-gaze too much about the act of blogging, but a gradual evolution in my own style was the primary motivation for my hiatus. In the good old days I stuck mostly to very short posts, pointing to this or that and making simple comments without feeling obligated to provide elaborate justifications for every little thing. But over time, I found myself increasingly seeing every post as a multi-layered 3,000 word essay. (Even if they didn’t end up that way in actuality, that’s how they often were in my head.) Not a sustainable model for someone for whom blogging is a hobby, not a vocation. I promised myself long ago that if blogging ever started to take up too much time (roughly, more than 3 hours/week), something would be broken and I’d have to fix it.

So here I am fixing it. I really do very much enjoy the idea of blogging, both exploring ideas for my own sake and the wider conversation with other bloggers and with commenters. But given unitarity constraints on my time and energy, I need to concentrate on punchier posts, and comments that are not fully supported against every possible counter-argument. If the experience of writing a book nudged me toward longer forms, the success of Twitter demonstrates the value of the quick hit & link. Of course I will mix things up, which is part of the fun — longer posts here and there, the occasional video. There may be LOLcats. But I’ll try to refrain from writing poetry.

And now for dessert: chocolate extravaganza from my favorite restaurant, Alinea in Chicago. Ordinarily there are no tablecloths at Alinea, but for this course they cover the table with a thin sheet of silicone and — well, you’ll see.

Some of you might find this presentation too precious and extravagant to be enjoyable. I understand, and I’m sure you’ll appreciate the Oreo Blender Blaster at Denny’s.

I just counted: this is my 1,540th blog post (counting my youthful efforts at Preposterous Universe.) About two posts every three days, for a bit over six years. Time for a break!

So I’m going on hiatus for a while. While my normal mode of operation is to bounce happily between a dozen different activities, there’s a time for consolidation, and I’d like to concentrate on research for a while. It’s been madcap travel ever since the book came out, which is finally done with, and I look forward to getting back into the groove of solving equations and writing papers.

My hiatus plans aren’t very firm: not sure whether it will be a month or a year. It won’t be permanent, that’s for sure. And I doubt it will even be very doctrinaire; if the mood strikes me, I won’t be reluctant to fire up the old laptop and post something on my beloved Cosmic Variance.

In the meantime, the rest of the crew (not to mention you commenters) will keep the fires burning here at the blog. Maybe I’ll even leave a comment or two if one of those jokers says something totally outrageous. Probably most people won’t even notice I’m gone. (Otherwise I wouldn’t have to announce it, would I?)

It’s that time of year again. Young graduate students, having toiled for several years at the feet of Science, are kicked out of the nest to take their places among the ancient and honorable community of scholars. If you will forgive the mixed metaphors.

This week we had a double-decker celebration: both Heywood Tam and Moira Gresham successfully defended their Ph.D. theses. Congratulations to both!

Heywood was stuck with me as an advisor, but he seems to have turned out okay. We worked together on a number of papers that looked into models of Lorentz violation, including issues of extra dimensions and stability. More recently we’ve been finishing a couple of papers on fine-tuning in the early universe — coming soon to a preprint server near you! In the Fall Heywood will leave the dry heat of SoCal for the damp heat of Florida.

Moira’s advisor was Mark Wise, but we also interacted quite a bit. She and I collaborated with Heywood and Tim Dulaney on a couple of aether papers, and she and Tim recently wrote a really interesting paper on anisotropic inflation. But she promises that her next project will be completely Lorentz-invariant. And she’ll be doing it from Ann Arbor, where she’ll be joining the Michigan physics department as a member of the Society of Fellows.

Always bittersweet when students graduate; it will be a loss to Caltech when the leave, but it’s great to see people launch their independent research careers. Best of luck to both Moira and Heywood!

Reporting back from a hotel in midtown Manhattan, having made it through the Colbert Report basically unscathed. In fact the experience was great from beginning to end. Update: here is the clip.

Monday morning I talked on the phone with Emily Lazar, a researcher for the show. I was really impressed right from the start: it was clear that she wanted to make it easy for me to get across some substantive message, within the relatively confining parameters of what is basically a comedy show. From start to finish everyone I dealt with was a consummate pro.

We got picked up at our hotel in a car that brought us to the Colbert studio, and hustled inside under relatively high security — people whispering into lapel microphones that we had arrived and were headed to the green room. Very exciting. The green room was actually green, which is apparently unusual. I got pep talks from a couple of the staff people, who encouraged me to keep things as simple as possible. They made an interesting point about scientists: they make the perfect foils for Stephen’s character, since they actually rely on facts rather than opinions.

Stephen himself dropped by to say hi, and to explain the philosophy of his character — I suppose there still are people out there who could be guests on the show who haven’t ever actually watched it. Namely, he’s a complete idiot, and it’s my job to educate him. But it’s not my job to be funny — that’s his bailiwick. The guests are encouraged to be friendly and sincere, but not pretend to be comedians.

We got to sit in the audience as the early segments were taped, which were hilarious. I feel bad that my own interview is going to be the low point of the show, laughs-wise. But I went out on cue, and fortunately I wasn’t at all jittery — too much going on to have time to get nervous, I suppose.

I had some planned responses for what I thought were the most obvious questions. Of which, he asked zero. Right off the bat Colbert managed to catch me off guard by asking a much more subtle question than I had anticipated — isn’t the early universe actually very disorderly? That would be true if you ignored gravity, but a big part of my message is that you can’t ignore gravity! The problem was, I had promised myself that I wouldn’t use the word “entropy,” resisting the temptation to lapse into jargon. But he had immediately pinpointed an example where the association of “low entropy” with “orderly” wasn’t a perfect fit. So I had to go back on my pledge and bring up entropy, although I didn’t exactly give a careful definition.

As everyone warned me, the whole interview went by in an absolute flash, although it really lasts about five minutes. There was a fun moment when we agreed that “Wrong Turn Into Yesterday” would make a great title for a progressive-rock album. Overall, I think I could have done a better job at explaining the underlying science, but at least I hope I successfully conveyed the spirit of the endeavor. We’ll have to see how it comes across on TV.

I shouldn’t end without including some good words about the bag of swag. Not only does every guest get a goodie bag that includes a bottle of excellent tequila, it also includes a $100 gift certificate for Donors Choose. How awesome is that?

And as we left the studio, there were some young audience members lurking around hoping for a glimpse of the great man himself. They had to settle for me, but they sheepishly asked if I would pose for a picture with them. Not yet having perfected my diva act, I happily complied. I hope they take away some great memories of the night.