Great elasticity demonstration

I've linked to Dustin Sandlin before.  He does a fantastic series of YouTube videos that are readily accessible by a lay audience and show why science is fun.  Here is his look, using ultrahighspeed video, at why dry spaghetti tends to break in at least three pieces when flexed from the ends.  As he says, this is something that Feynman himself couldn't readily unravel.  Watch the video before you scroll down and read my spoiler description of the mechanism.

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This video shows some great elasticity concepts that we generally don't teach in the undergrad physics curriculum.  Flexing the noodle puts the top in tension and the bottom in compression - if you assume simple elasticity (e.g., stress = (Young's modulus)(strain)), and you consider the resulting forces and torques on a little segment of the noodle, you can calculate the shape (e.g., vertical deflection and tilt angle as a function of position along the noodle) of the bent spaghetti, though you have to assume certain boundary conditions (what happens to the displacement and tilt at the ends).  As the flexing is increased, at some point along its length (more on this in a minute) the noodle fractures, because the local strain has exceeded the material strength of the pasta.  One way to think about this is that the boundary condition on one end of each piece of the noodle has now changed abruptly.  Each piece of noodle now starts changing shape, since the previous strained configuration isn't statically stable anymore.  That shape change, the elastic information that the boundary condition has changed, propagates away from the fracture point at the speed of transverse sound in spaghetti (probably a couple of km/s).  The result is a propagating kink in the noodle, the severity of the kink depending on the local curvature of the pre-fracture shape.  If that local strain again exceeds the critical threshold, the noodle will fracture again.  The fact that we need really high speed photography to see the order of breaking shouldn't be that surprising - the time interval between fractures should be the size of the noodle fragment (around 3 cm) divided by the speed of sound in the pasta (say 2000 m/s), or around 15 microseconds!  (If I was really serious, I'd go the other way and use the video record of the propagating kink to measure the speed of transverse sound in pasta.)

This problem is actually somewhat related to another mechanics question: why do falling chimneys tend to break into three pieces?  Again, treating the chimney as some kind of elastic beam clamped at the bottom but free at the top, one can find the (quasi static, because the time it takes sound to propagate in the chimney material is much shorter than the time for the chimney to fall) shape of the flexing chimney.  There are two local maxima in the strain, and that's where the chimney tends to break.  Note that the chimney case is quasi static, while the spaghetti case really involves the dynamics of the flexing noodle after fracture. 

The bottom line:  I want one of those cameras.

Lack of self-awareness, thy name is John Horgan.

I see that Scientific American is reorganizing its blogging efforts.  I hope it works out well for them.  Call me if you want someone to blog about condensed matter and nanoscale science.  I'd really enjoy talking to a wider audience and would, of course, tailor my style accordingly.

When looking at their site, though, I came upon this piece by John Horgan, about whom I have written previously.  This latest essay is meant to be advice for young science writers.  Because he is a smart person with great experience in science journalism, his basic advice does have some kernels of merit (be skeptical of claims of scientists; pay attention to who is talking about science and their possible agendas).  His other points strike me as odd or beside the point to varying degrees.  (e.g., scientists are people and therefore have a human context to their work, but claiming that the majority of US science is shaped by capitalism and militarism is just nutty; inequality, our screwed up healthcare system, and militarism are all distressing, but what does that have to do with talking about a large part of science?)

The very first point that Horgan makes got my attention, though, and nearly broke my irony-meter.  He writes (his emphasis): "Most scientific claims are bogus. Researchers competing for grants, fame, glory and tenure often—indeed usually–make exaggerated or false claims, which scientific journals and other media vying for readers eagerly disseminate."  While I recognize that there have been claims to this effect in recent years, I think it is pretty hilarious that Horgan can warn about this with a straight face.  This is the guy who vaulted onto the larger, international stage by writing a book called The End of Science back in 1996.  Yeah, that wasn't at all an exaggerated or false claim made with the intent of capturing as much media attention as possible.  Nope.

Long odds: Proposals and how we spend our time

We just completed the two-day kickoff symposium of the Rice Center for Quantum Materials.  It was a good meeting, and the concluding panel discussion ended up spending a fair bit of time talking about the public policy challenges facing basic research funding in the US (with some discussion of industry, but largely talking about government support).  Neal Lane is an impressive resource, and lately he and Norm Augustine have been making the rounds in Washington trying to persuade people that it's a dire mistake to let basic research support continue to languish for the foreseeable future.

Over the December/January timeframe, I'm spending time on several grant proposals.  Three of them have a priori odds of success (based on past years, dividing awards by the number of initial proposals) less than 5%.  Now, obviously longshots have their place - you can't win if you don't play, and there is no question that thinking, planning, and writing about your ideas has utility even if you don't end up getting that particular award.  Still, it seems like more and more programs are trending in this awful positive feedback direction (low percentage chance per program = have to write more grants = larger applicant pool = lower percentage chance).  Many of these are prestigious center and group programs that are greatly desired by universities as badges of success and sources of indirect costs, and by investigators as sources of longer term/not-single-investigator support.  When yields drift below 5%, it really does raise questions:  How should we be spending our time, one resource that we can never replenish?  Does this funding approach make sense?  When the number of potentially "conflicted" people (e.g., coauthors/collaborators over the last four years for every person affiliated with a big center grant) exceeds 1000 (!), who the heck is left to review these things that has any real expertise?

Science and sensationalism: The allure of superlatives and bogus metrics

I helped out a colleague of mine today, who was fact-checking a couple of sentences in a story that's going to come out in a large circulation magazine (that shall remain nameless).  The article is about graphene, and in draft form included a sentence along the lines of "Graphene is 1000x better at conducting electricity than copper."  That sounds great and exciting.  It's short, simple, and easy to remember.  Unfortunately, it's just not true unless accompanied by a huge asterisk that links to a page full of qualifications and disclaimers. 

The challenge:  Come up with a replacement that gets the main point across (graphene is a remarkable material) without being a gross distortion or dissolving into scientific jargon. 

My response:  "Graphene is an electrical conductor that rivals copper and silver, and is much lighter and stronger."  At least this is true (or moreso, anyway), though it's longer and doesn't have an easy-to-remember number in it. 

The search for a simple, one-sentence, exclamatory pronouncement can lead science journalists (and university public relations people) down a dangerous path.  Often really great science is simply more complicated than a sound-bite.  Moreover, the complications can be fascinating and important.  It takes a special journalist to recognize this.

Interesting superconductivity developments

Three superconductivity-related things during the crazy end-of-semester time crunch. 

First, the paper that I'd mentioned here has been accepted and published in Nature Materials here.  That one reports signatures of superconductivity in a single atomic layer of FeSe on SrTiO₃ at around 100 K.  This result is not without controversy, as it's very hard to do standard transport in single layers of material like this in UHV, and usually people want to have multiple signatures besides resistivity when claiming superconductivity.

In that vein, there is a recent preprint that reports superconductivity above 190 K (!) in H₂S under high pressure.  The belief by the authors is that this is conventional superconductivity, related to classic work over many years (see here and here for example) by Neil Ashcroft and others discussing superconductivity in metallic hydrogen (possibly responsible for things like Jupiter's large magnetic field, for instance).  Because of the challenges of doing ultrahigh pressure measurements in diamond anvil cells, this, too, has only resistivity apparently dropping to zero as its main evidence for superconductivity.  It looks pretty cool, and it will be interesting to see where this goes from here.

Lastly, in Nature there is a paper that looks at trying to understand recent measurements of copper oxide superconductors when hit with ultrafast laser pulses.  The argument in those pump-probe experiments is that smacking the cuprates while in the normal state is enough to produce apparent transient superconductivity (as inferred on picosecond timescales with another optical pulse used to measure a quantity related to the conductivity).  The new paper claims that the initial pulse produces lattice distortions that should favor higher temperature superconductivity.

The common thread here:  There continue to be tantalizing hints of possible higher temperature superconductors, but in all of these cases it's really darn hard to do the measurements (or at least to bring multiple tools to bear).  For a nice look at this topic, see these recent words of wisdom.

Writing style, "grand visions", and impact

It's hard for me to believe that over eight years (!) have passed since I wrote this.  Recently I've been thinking about this again.  When writing proposals, it's clearly important to articulate a Big Picture vision - why are you working on a problem, where does that problem fit in the scheme of things, and what would the consequences be if you achieved your goals?  Some people's writing styles tilt more in this direction (e.g., our team is smart and highly accomplished, and we have a grand vision of a world set free by room temperature superconductors - this path will lead us there) and others lean more toward the concrete (e.g., our team is smart and highly accomplished, and we've thought carefully about an important problem - here is what we are going to do in some detail, what the challenges are, and what it will mean).  I tend to lean toward the latter.  It's not that I lack a grand vision - I'd just rather underpromise and overperform.  Still, it's clear that this doesn't always pay dividends.  (Of course, the best of all possible worlds is to promise a grand vision and actually achieve it, but that's extremely rare.)

Beautiful mechanical design, + excellent outreach

Yesterday I came across this video series, put up by "EngineerGuy" Bill Hammack.   It shows a mechanical analog computer originally designed by Michelson for building up Fourier series (sums of sinusoids) of up to twenty integer multiples of a fundamental frequency.   Moreover, you could use this machine to go backwards, and mechanically do Fourier decomposition of periodic waveforms.  It's really wonderful.  I would love to have one to use as a teaching tool, and I'm sure some enterprising person will figure out how to 3d print all the relevant parts (except the springs and cables), or perhaps build one out of Lego. 

I also wanted to point out Hammack's other videos.  This is great outreach - really accessible, clear, well-produced content.

Chapter epigraphs from my book

Because of the vagaries of British copyright law and their lack of the concept of "fair use", I am not allowed to use clever little quotes to start the chapters of my nano textbook unless I have explicit permission from the person or their estate.  Rather than chasing those, I've sacrificed the quotes (with one exception, which I won't reveal here - you'll have to buy the book).  However, on my blog I'm free to display these quotes, so here they are.

• "I would like to describe a field, in which little has been done, but in which an enormous amount can be done in principle. This field is not quite the same as the others in that it will not tell us much of fundamental physics (in the sense of, “What are the strange particles?”) but it is more like solid-state physics in the sense that it might tell us much of great interest about the strange phenomena that occur in complex situations. Furthermore, a point that is most important is that it would have an enormous number of technical applications. What I want to talk about is the problem of manipulating and controlling things on a small scale."  - Richard Feynman, "There's Plenty of Room at the Bottom" lecture, Engineering and Science 23, 22 (1960)
• "More is different." - Phil Anderson, Science 177, 393 (1972).
• "Solid state I don’t like, even though I started it." - Wolfgang Pauli, from AIP's oral history project
• "How do we write small? ... We have no standard technique to do this now, but let me argue that it’s not as difficult as it first appears to be." - Richard Feynman, "There's Plenty of Room at the Bottom" lecture, Engineering and Science 23, 22 (1960)
• "God made solids, but surfaces were the work of the devil." - Wolfgang Pauli,  quoted in Growth, Dissolution, and Pattern Formation in Geosystems (1999) by Bjørn Jamtveit and Paul Meakin, p. 291.
• "The importance of the infinitely little is incalculable." - Dr. Joseph Bell, 1892 introduction to Arthur Conan Doyle's A Study in Scarlet
• "Magnetism, as you recall from physics class, is a powerful force that causes certain items to be attracted to refrigerators." - Dave Barry, 1997
• "If I were creating the world I wouldn’t mess about with butterflies and daffodils. I would have started with lasers, eight o’clock, Day One!" - Evil, Time Bandits
• "Make big money!  Be a Quantum Mechanic!" - Tom Weller, Science Made Stupid (1985). 
• "I am an old man now, and when I die and go to Heaven there are two matters on which I hope for enlightement. One is quantum electrodynamics and the other is the turbulent motion of fluids. And about the former I am rather more optimistic." - Horace Lamb, 1932 address to the British Association for the Advancement of Science, as cited in Eames, I., and J. B. Flor. "New developments in understanding interfacial processes in turbulent flows." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369.1937 (2011): 702-705
• "Almost all aspects of life are engineered at the molecular level, and without understanding molecules we can only have a very sketchy understanding of life itself." - Francis Crick, What Mad Pursuit: A Personal View of Scientific Discovery (1988), p. 61
• "Be a scientist, save the world!" - Rick Smalley 

Refereeing redux.

I was also asked:

"I would like to see a post addressing how to handle a paper sent back by the editor for another round of reviews. Of particular interest to me: what do you do if you notice errors that escaped notice (or weren't present) in the original manuscript? What if the authors answered your issues well in the response letter, but didn't include those modifications in the manuscript? What advice would you have if the authors have clearly done the experiments and theory well, and the results are worth publishing, but the writing/figures are still not at a publishable level following their revisions?"

My answers are probably what you'd guess.  I try hard to identify possible errors the first time through refereeing a paper.  If I spot something on the second round that I'd missed, I try to be clear about this by writing something like "Also, on this pass through the paper, I had the realization that [blah blah] - my apologies for not catching this on the first round, but I think it's important that this issue be addressed."  Again, I try hard not to miss things on the first pass, since I know how annoying it is from the author side to be hit with apparently new objections that could have been addressed in the first revisions.

I've definitely had cases where the authors wrote a great response and then made almost no changes to the manuscript.  In this situation, I usually say, "The response letter was very convincing/clarifying regarding these points, and I think it is important that these issues are discussed in the manuscript itself."  I would then, in the "comments to the editor" part of the report, re-emphasize this, in the hopes that the editor will push the authors about it.

If the manuscript contains good science but is written at an unpublishable level (rare, but not unheard of), I try to point this out diplomatically (e.g., "The science here is very interesting and deserving of publication, but I strongly recommend that the presentation be revamped substantially.  I think swapping the order of the figures would make the story much clearer.").  Again, to the editors, I might make more specific recommendations (e.g., "This manuscript absolutely needs to be closely edited by a native speaker of English" if it's full of truly poor grammar).

The basic strategy I follow is to try to evaluate the science and offer as useful and constructive feedback as possible (given that I can't spend tons of time on each refereeing assignment), in the kind of professional and courteous tone I'd like to read in reports on my own work.

"What happened to PRL?"

A commenter wrote the following:  "About PRL, I do have a concrete question. You've been around for some time, I am new in the business. Can you explain what happened to it? Twenty years ago it used to be the journal to publish in, now it is an afterthought."

Physical Review Letters remains a premier place to publish high impact physics results in letter-format (that is, typically 4-ish page papers with around 4 figures).   I think that the recently arrived editor in chief Pierre Meystre is working hard to revitalize PRL as a "destination journal" for physics results, where you know that the primary audience comprises physicists. 

That being said, the origins of some of PRL's (possible) loss of cachet are immediately obvious.  Twenty years ago, Nature and Science were not as highly regarded within the physics community as places to publish.  Nature Publishing Group did not have all of its various progeny (Nature Physics, Nature Materials, Nature Nanotechnology, Nature Photonics being the four most relevant here).  Likewise, the American Chemical Society's journal offerings used to be a lot less friendly to physicists.  Now there are Nano Lett., ACS Nano, ACS Photonics, ACS Applied Materials and Interfaces.   It's a far more competitive journal marketplace, and the Phys Rev journals have been slow to innovate.  Furthermore, I think there is a broad perception that PRL's refereeing can be long, arduous, contentious, and distressingly random.  Some of the competing journals somehow are able to be rapid and on-target in terms of the expertise of the referees.  If you have a hot result, and you think that refereeing at PRL is highly likely to take a long time and require a protracted fight with referees, other alternatives have room to make inroads. 

Somehow PRL needs to improve its reviewing reputation in terms of accuracy and timeliness.   That, I think, would be the best way to be more competitive.  That, and a re-design of their webpage redesign, which is neither particularly attractive or functional.

What are skyrmions?

Skyrmions are described somewhat impenetrably here on wikipedia, and they are rather difficult beasts to summarize briefly, but I'll give it a go.  There are a number of physical systems with internal degrees of freedom that can be described mathematically by some kind of vector field.  For example, in a magnetically ordered system, this could be the local magnetization, and we can imagine assigning a little vector \( \mathbf{m}\) (that you can think of as a little arrow that points in some direction) at every point in the system.  The local orientation of the vector \( \mathbf{m} \) depends on position \(\mathbf{r}\), and there is some energy cost for having the orientation of \( \mathbf{m} \) vary between neighboring locations.   In this scenario, the lowest energy situation would be to have the direction of \(\mathbf{m}\) be uniform in space.

Now, there are some configurations of \( \mathbf{m}(\mathbf{r})\) that would be energetically extremely expensive, such as having \( \mathbf{m}\) at one point be oppositely directed to that at the neighboring sites.  Relatively low energy configurations can be found by spreading out the changes in \(\mathbf{m}\) so that they are gradual with position.  Some of these are topologically equivalent to each other, but some configurations of \(\mathbf{m}\) are really topologically distinct, like a vortex pattern.  Examples of these topological excitations are shown here.   With a lone vortex, you can't trivially deform the local orientations to get rid of the vortex.  However, if you combine a vortex with an antivortex, it is possible to annihilate both.

Skyrmions (in ferromagnetis) are one kind of topological excitation of a system like this.  They are topologically nontrivial "spin textures", and in real magnetic systems they can be detected through techniques such as magnetic resonance.   It's worth noting that there are other topological defects that are possible (domain walls that can be soliton-like; defects called "cosmic strings" if they are defects in the structure of spacetime, or "line defects" if they are in nematic liquid crystals; monopoles (all arrows pointing outward from a central point) sometimes called "hedgehogs"; and other textures like the boojum (a monopole pinned to the surface of a system; relevant in liquid crystals and in superfluid ³He)).  With regard to the last of these, I highly recommend reading this article, which further cemented David Mermin as a physics and science communication idol of mine.

Ask me something.

I haven't done this in a while.  Are there any particular subjects that you would like me to address, or concepts to explain?  It's a busy semester, but I can try....

Some interesting links: Books and news

Here are some things that I wanted to share with my readership:

• My friend Arjendu Pattanayak (founder of a very good blog) pointed out to me this book by Kittel.  It's really nice - it is very concise and tightly written without being incomplete, and it's cheap.
• On a lighter note, Science...For Her! is a book by a friend of a friend.  The introductory video is here.  Attention Physics Today:  I volunteer to review this book when it comes out.  Seriously, I'd be happy to do it, and I think it would be great for some amount of wry humor to make its way into the pages of PT.  
• Similarly, Randall Munroe's book What If? is magnificent.   Attention Physics Today:  I volunteer to review this one, also.  If you don't review this book, you are entirely humorless.
• The MIT Technology Review has a fun article in it about topological quantum computing with non-Abelian anyons.  The reason it's fun is that it talks about the people involved (including my postdoctoral mentor) and manages to avoid becoming overly technical. 
• A few people have pointed out to me that Lockheed Martin has made a rather strong press statement regarding a fusion reactor scheme being developed by Skunk Works (the folks who brought us the SR-71 and the F-117, among other things).   This is potentially interesting, but it's really hard to tell whether this is all vaporware so far.  It looks like a magnetic mirror configuration, something that has been explored extensively over the last few decades, and they don't provide enough technical discussion to figure out what they're doing that's different.  Still, there seem to be many takers trying alternatives to tokomaks (Washington, and what Nature termed "fusion upstarts"), and it's surely worth a shot.  
• I listened in on a conference call today from Benefunder.  These people are trying to come up with an alternative philanthropic approach to research funding that isn't crowdsourcing.  Any commenters already sign up with them?

Quantitatively, how amazing are modern electronics technologies and materials?

I've talked before about how condensed matter/materials physics/engineering is so ubiquitous that it somehow fades into the background, and people don't appreciate how truly wondrous it is.  I thought I'd compile a few stats to try and drive this home.

• A typical car contains something like 30,000 discrete parts, if you count down to the smallest individual screw.  By comparison, a typical microprocessor has around (to make the numbers work out conveniently) 3 billion transistors.  That's a factor of a million more constituents.  Bear in mind that essentially all of those transistors work, without fail, for a decade or more.  (When was the last time you actually had a processor failure, rather than a power supply or hard drive issue?).   Imagine taking a million cars, and claiming that they will all run, flawlessly, with no broken parts, for a decade.  
• Parallel manufacturing is a wonderful thing.  If you built the 3 billion transistors serially at a rate of one per second, it would take around 95 years to put together a processor.  
• There is a famous study that proved that Kansas is actually flatter than a pancake.  Perfect flatness would correspond with their flatness metric equalling 1, and they found that Kansas has a flatness of 0.9997.  By that measure, a 300 mm silicon wafer used to fabricate chips would have a flatness on the order of 1 - (30 nm/300mm) = 1 - 10^-7.  If your dining room table was that flat, the typical height of a surface defect would be well under the wavelength of visible light.  If Kansas was that flat, the tallest feature in the state would be a few cm high.
• The worst silicon purity acceptable for Si electronics processing is around 0.1 parts per billion.  That means that a single impurity atom in such silicon is more rare than, well, you as a member of the population of the earth.  
• We have the ability to position particular devices with (roughly) few nm precision and accuracy on a processor of cm scale.  That's equivalent to being able to place an item on your desk in a particular place to within about 1/50th the diameter of a human hair.

If none of this impresses you, you're pretty jaded.

Chapman Lecture - Paul McEuen

We were very fortunate last week to host Paul McEuen for our Chapman Lecture series (previous speakers here).  NAS member, successful novelist, director of LASSP at Cornell - typical underachiever.  The talk was tremendous fun, a look at several cool experiments going on in his lab examining the mechanical properties of graphene (which acts surprisingly like paper, and taught me about the Foppl/von Karman number, \(YL^2/\kappa\), where \(Y\) is the Young's modulus, \(L\) is a relevant length scale, and \(\kappa\) is the bending stiffness) and nanotubes.  The best part of the talk (apart from the rendition of the Cornell alma mater as played by electrically plucked carbon nanotubes) was the palpable sense of joy that he conveyed to the students in the audience.  He clearly really enjoys the playing-with-toys aspect of research!

Annual Nobel speculation

It's that time of year again - go ahead and speculate away in the comments about possible Nobel laureates in physics or chemistry.  Natural suggestions in physics include Aharonov and Berry for geometric phases, Vera Rubin for dark matter/galaxy rotation curves, Charlie Kane and Shoucheng Zhang (and possibly Molenkamp) for topological insulators, Pendry, Smith, and Yablonovitch and John (oh dear that's four) for metamaterials and/or photonic bandgaps.

Update:  check out Slate's article on deserving women candidates.  Dresselhaus would be a good choice.  (I'm not as big a fan of, e,g., Lisa Randall, who is extremely smart but is in the space of high energy theorists who have not yet had predictions of exotic physics actually verified by experiment.)

AAAS, Science magazine, and figure permissions

Hello readers - As I'd mentioned previously, I've written a nano textbook that's going to come out next year.  I'd like to ask my readership, on the off-chance that someone has a suggested contact:  Please email me if you can suggest a good contact at AAAS/Science, with whom I could have a discussion regarding figure permission fees.  (I'd like to try talking to someone first before turning this into a major blogging topic.)  Thanks.
Update:  I've made contact with an actual person.  We will see what happens....

Penny-wise, pound-foolish: Krulwich blog

I just read that NPR is getting rid of Robert Krulwich's excellent science blog, allegedly as part of cost-cutting.  Cost-cutting?  Really?  Does anyone actually think that it costs a huge sum of money to run that blog?  Surely the most expensive part of the blog is Robert Krulwich's time, which he seems more than willing to give.  Seriously, we should find out what the costs are, and have a kick-starter project to finance it.  Come on, NPR.

The persistent regional nature of physics

In the 21st century, with the prevalence of air travel, global near-instantaneous communications, and active cultures of well-financed scientific research on several continents, you would think that the physics enterprise would be thoroughly homogenized, at least across places with similar levels of resources.  Sure, really expensive endeavors would be localized to a few places (e.g., CERN), but the comparatively cheap subfields like condensed matter physics would be rather uniformly spread out.

Strangely, in my (anecdotal, by necessity) experience, that doesn't seem to be the case.  One area of my research, looking at electronic/optical/thermal properties of atomic and molecular-scale junctions, has a very small number of experimental practitioners in the US (I can think of a handful), though there are several more groups in Europe and Asia.  Similarly, the relevant theory community for this work, with a few notable exceptions, is largely in Europe.   This imbalance has become clear in terms of both who I talk with about this work, and where I'm asked to speak.  Interestingly, there are also strong regional tendencies in some of the citation patterns (e.g., European theorists tend to cite European experimentalists), and I'm told this is true in other areas of physics (and presumably chemistry and biology).  I'm sure this has a lot to do with proximity and familiarity - it's much more likely for me to see talks by geographically proximal people, even if it's equally easy for me to read papers from people all over the world.

Basically, physics areas of pursuit have a (surprising to me) large amount of regional specialization.  There's been a major emphasis historically on new materials growth and discovery in, e.g., Germany, China, and Japan compared to the US (though this is being rectified, in part thanks to reports like this one).  Atomic physics w/ cold atoms has historically been dominated by the US and Europe.   I'm sure some of these trends are the result of funding decisions by governments.   Others are due to the effect of particularly influential, talented individuals that end up having long-lasting effects because the natural timescale for change at universities is measured in decades.  It will be interesting to see whether these inhomogeneities smooth out or persist over the long term.

Hype, BICEP2, and all that.

It's been a few years since I've written a post slamming some piece of hype about nanoscience.  In part, I decided that all this-is-hype posts start to sound the same and therefore weren't worth making unless the situation was truly egregious or somehow otherwise special.  In part, I also felt like I was preaching to the choir, so to speak.  That being said, I think the recent dustup over the BICEP2 experiment is worth mentioning, as an object lesson.   

• If the BICEP2 collaboration had only posted their paper on the arxiv and said that the validity of their interpretation depended on further checks of the background by, e.g., the PLANCK collaboration, no one would have batted an eye.  They could have said that they were excited but cautious, and that, too, would have been fine.  
• Where they (in my view) crossed the line is when they orchestrated a major media extravaganza around their results, including showing up at Andre Linde's house and filming his reaction on being told about the data.  Sure, they were excited, but it seems pretty clear that they went well beyond the norm in terms of trying to whip up attention and recognition.
• While not catastrophic for science or anything hyperbolic like that by itself, this is just another of the death-by-1000-cuts events that erodes public confidence in science.  "Why believe what scientists say?  They drum up attention all the time, and then turn out to be wrong!  That's why low fat diets were good for me before they were bad for me!"
• Bottom line:  If you are thinking of staging a press conference and a big announcement before your paper has even been sent out to referees, please do us all a favor and think again.