March Meeting day 2

Today was probably the maximum crowd at the APS meeting. Saw a number of talks and had lots of conversations. One particularly interesting talk was about variations on this result. In condensed matter we've become used to the idea of "photonic band gap" or "photonic crystal" materials, systems where a spatially periodic pattern of dielectric contrast (e.g., glass vs. air) results in optical properties that mimic the electronic properties of crystals: bands (energy ranges) where light can propagate freely, and (photonic) band gaps, where light is reflected and can't propagate. This talk was about weird "hyperuniform" disordered dielectric structures that nonetheless have a complete photonic band gap (in all directions) in 2d, and the fact that by introducing voids and defects in these systems, it's possible to make very selective and directional waveguides. I need to read more about the math behind this. The experiment uses microwaves rather than visible light, meaning that it's possible to build such structures by hand using sapphire plates and rods on the centimeter scale.

The Buckley Prize session was also very good, though I missed talks in the middle. Very crowded, particularly for Charlie Kane's talk. That one would have been fun if it'd been a full hour - it felt like he had to abbreviate some of the discussion to fit into the 30+6 minute slot.

Another highlight this afternoon was the big Kavli session about the mesoscale. The lead talk was from Bob Laughlin, who is always entertaining. He focused on the big open question of whether there are laws that emerge in biology. By his definition, a law is a quantitative relationship between measured parameters that always holds. Some laws are (apparently) fundamental, like the force between two point charges in vacuum. Others are emergent, like the relationship between stress and strain in elastic media, or the Navier-Stokes equations that govern hydrodynamics. In the emergent situation, emergent laws hold when the system is sufficiently macroscopic. Laughlin's big question is, are there universal quantitative relationships that emerge in biological systems (beyond the trivial ones already mentioned, like elasticity being useful for describing cell membranes)? He says that there are hints all over, but it's very hard to do the definitive experiments because biology is just so complicated and our experimental tools are comparatively invasive and crude. When asked to describe biologists in one word, he said "frustrated".

The talk also put forward two definitions of what condensed matter physicists do, both of which are very good. Via Laughlin, Michael Fisher says: "Our job [as condensed matter physicists] is to discover and understand the phases of matter and the transitions between them." Laughlin himself says: "Our job [as condensed matter physicists] is to discover the emergent laws of nature, and hand them to engineers so that they can be put to use." Good stuff. On a lighter note, I realized partway through the talk that every now and then it's entertaining to imagine Laughlin's words as if said by William Shatner. "We trust the emergent laws of rigidity and hydrodynamics...to make an airplane...that can go up to 35000 ft...and not...explode!"

March Meeting day 1

As I am every year, I was again somewhat shocked by how many people come to this meeting. The attendance just keeps going up, and unfortunately that usually correlates with a decrease in the utility of the average talk. For PIs, the meeting is more about interacting with each other, vendors, potential hires (postdoc or faculty) than it is about actually learning things from talks.

I did actually learn a few things in talks yesterday, though, even without going to sessions on the super hot topics (graphene, topological insulators).

I went to the first half of an interesting session about presenting science to the public, something that I think is very important. The first talk was about a theater group collaborating with MIT, with a history of developing plays based on physics (including Einstein's Dreams by Alan Lightman). Here, free of charge, are my suggestions for other play possibilities: The birth of Silicon Valley, emphasizing that in many ways it stems from the fact that Shockley was such a micromanager that no one could work with him; the genesis of the hydrogen bomb, emphasizing that Teller's difficult personality delayed the development of his much-loved "super" by at least two years, because very few people could work with him. (Sense a theme?). The second talk was by Odd Todd Rosenberg, an animator who works with Robert Krulwich of ABC and NPR science fame. The cartoons were funny and informative, though the discussion raised the recurring issue of oversimplification and inaccuracy in broadly popular marketing of science.

I also went to a very strong session all about vanadium dioxide, which was quite informative. Sounds like many people in the strong correlations game are starting to look very hard at ionic liquids for gating. Here the major challenge is whether people are inadvertently (or advertently) doing chemistry on their structures.

There was also a very fun talk by Hongkun Park of Harvard, who discussed "quantum plasmonics" - trying to couple individual emitters and absorbers to plasmonic waveguides. For example, you can have a GaAs nanowire touching a silver nanowire. When biased appropriately the GaAs emits photons which couple strongly into guided plasmon modes of the Ag wire, propagate as plasmons, and are then generate photocurrent at a junction with a Ge nanowire at the other end of the silver wire. This is a "dark plasmonic" circuit, with light being generated, propagated, and detected on the subwavelength scale. Cool stuff.

March Meeting program and app

For an organization so deeply ingrained with technology, the American Physical Society has some surprising issues. For example, as I type this, I'm downloading the complete program to the March Meeting at the blazing pace of 5 kB/s, and that's not limited by my connection. For another example, once again the APS has released a mobile app that contains the whole program and is supposed to be searchable. Unfortunately, the user interface on the app (at least the ipad version) is dreadful, unintuitive, and creepingly slow. Geez.

Job interview humor.

Thanks, Wolff, for pointing me to this.

Coming up this week, some commentary from the March Meeting of the APS.

superluminal neutrinos - not (quite) dead yet.

When historians of science look back on the whole OPERA superluminal neutrino discussion, one way or the other, there are going to be a number of lessons to draw from the experience about how science and science journalism function in the early 21st century.

Yesterday, with "BREAKING NEWS" headlines, Science magazine proclaimed: "Error Undoes Faster-Than-Light Neutrino Results". In that article, "according to sources familiar with the experiment", the whole timing discrepancy for the neutrinos is traced to a bad fiber optic connection to a GPS receiver. The claim from that article is that "After tightening the connection then remeasuring the time it takes data to travel the length of the fiber, researchers found that the data arrive 60 nanoseconds earlier than assumed." Since that's the critical amount by which the neutrinos allegedly arrived too soon for special relativity, that would seem to be the end of the story. Embarrassing for OPERA, but case closed, right? T

Wrong. First, on its face, this seems weird - no one is quoted by name, and the idea that a loose fiber coupling could contribute 60 ns in timing is pretty odd (since that would correspond to something like 18 m of free space optical path). At minimum, the description above must be garbled.

Moreover, the actual email from the CERN director does not say this at all. Rather, it says that OPERA has identified two outstanding issues, one involving an oscillator that provides timestamps for the GPS synch, and an optical fiber connector that brings the GPS signal to the OPERA master clock. The former issue could make the neutrino timing problem worse, in fact. Moreover, the message says explicitly that they are going to take new measurements in May to check these issues. That seems to flatly contradict the news article claiming that they've already done tests. For a detailed discussion, see Matt Strassler's excellent blog here.

Bottom line: as I've said before, the superluminal neutrino result is almost certainly wrong, but the jury is still out on how and why, despite what the Science news blurb says. Believe me, if they knew for sure how this stood, they'd end it with a definitive statement, not stretch this out 'til May.

UPDATE:  Prof. Strassler has the best write-up of this, based on detailed reporting from the European press.   Because of two different, subtle technical flaws, the uncertainty in the OPERA results is bigger than the 60 ns timing discrepancy, meaning (1) the result is not in contradiction w/ special relativity (big surprise), and (2) they need to run with fresh data and the problems rectified to make any more definitive statement.

Symmetry, crystals, and "time crystals"

"Spontaneous symmetry breaking" is a profound idea from condensed matter physics that has been adopted with a vengeance by the high energy physics community. Let me give an example. The laws of physics are, as far as we know, "translationally invariant" - they don't depend on our location in space, and if we move a little bit nothing happens to those laws. That's translational symmetry (and it turns out it's deeply connected to conservation of momentum, but that's another story). However, if we consider atoms moving about in space and worry about what configurations they like to adopt, the atoms tend spontaneously to adopt a lower symmetry state. For example, atoms will often arrange themselves into a regular spatial periodicity that we call a crystal structure. Now instead of space being continuously translationally invariant, the arrangement of atoms has a discrete translational symmetry - the arrangement of atoms reproduces itself if translated by integer multiples of a particular lattice parameter.

This week, two papers (here and here) appeared, from (the polymath) Frank Wilczek's group at MIT. Wilczek is one of the rare theorists who moves seamlessly between condensed matter and high energy theory. In these papers, the idea of "time crystals" is discussed. As science fiction-y as this sounds, it's real, but it is an application of this idea of spontaneous symmetry breaking, not some exotic Doctor Who concept. In analog with the above discussion, as far as we know, the laws of physics are also invariant under translations in time. The idea in these papers is that dynamical systems may spontaneously break that continuous translational invariance, and exhibit discrete time translation invariance instead. That means that dynamical systems may spontaneously take on periodicity in time! I need to read the second paper in detail soon - the quantum versions of these ideas seems very deep....

Meme contest

There's a new meme floating around the web these days. Here's an example:

I'd like to propose a contest for a version of this for "Physicist", or even better, "Condensed Matter Physicist", "Nanotechnologist", or something along those lines. Put up some nominations (links in the comments), and I'll have voting to pick a winner.

Gaming the system

Two semi-related topics have come to mind lately.  First, this post by the FSP caught my attention, regarding "citation circles", where a sub-community within a scientific discipline agree to cite each others' work.  I've heard of such things, and there's nothing inherently wrong there as long as the citations are relevant and don't consciously omit other equally relevant papers.  Still, I never considered this practice to have too much impact.  Back when I was in grad school, I'd heard of something that is equally fine ethically, and perhaps more important to progress in the long term:  the timely reviewing circle - a group of scientists who agree to respond promptly to invitations to review one anothers' work.  This is not a matter of conspiring to give positive reviews, but an agreement to get manuscripts through the review process quickly.  Imagine if certain "Letters" journals were actually speedy!

The second topic is the idea of trying to influence the selection of referees.  Of course, under many circumstances you as an author can suggest possible referees for scientific papers or grant proposals.  Let's call that a first-order influence.  It's a way of making sure that the editors can get the paper out to technically knowledgeable people in a specialty.  (I've been told by multiple editors that authors who try to suggest "friendly" referees often do themselves more harm than good, because those suggested reviewers are often more harsh than randomly selected peers.)  Recently I learned about a "higher-order" approach:  avoiding citing the work of potentially hostile reviewers, under the assumption that the editor/program officer often gets referee ideas from the reference lists.  I am very skeptical that this approach could matter in a statistically significant way.

Science and politics - 2 items

I really got a kick out of this video, and this one (some overlap), of President Obama at the White House Science Fair.  See here for a press description, and here for the White House's own page on the matter.  Note that Bill Nye was there - how cool is that?  It's great to see a President who uses a bit of the prestige of the office to shine a spotlight on the importance of science education.   

On an unrelated note, on the way home from work today I heard this story on NPR, about the challenges of nonprofits, specifically charities, that fund science research.  There is a tendency for those charities to shy away from politically controversial topics (e.g., human embryonic stem cells) because charities don't want to risk alienating any potential donor.  It is an interesting set of issues.  Charities are of course not obligated to fund any specific thing.  My sense is that one clear ethical line is that charities should be open and honest about what they do and don't support.  No hidden agendas.  If you don't want to fund something, just say so clearly, so that there's no "buyer's remorse" from donors who feel mislead.

Media relations at universities

Many people online have heard about and commented on this sad story.  An assistant prof in molecular biology at Case Western published a paper in the "journal" Life that purported to explain essentially all of creation in terms of "gyres", some hand-wavy vortex-like entities.  As the always provocative PZ Myers points out, the paper itself is basically word salad - it sounds disturbingly like the writings of someone having real mental health issues.  The fact that it got published shows what a sham some journals are.  I suspect that many of my academic peers have gotten email invitations to serve on the editorial boards of pay-to-publish journals.  Several members of the board at Life have apparently resigned over this mess.  However, this sad affair does raise some points worthy of consideration:

1) How did the media services office at CWRU actually end up putting out a big press release about this?  Do they simply have no judgment whatsoever about content?  I mean, could any professor ask them to put out a press release about anything, and it wouldn't be filtered at all before going out to the media?

2) Do aggregators like Eurekalert and Physorg serve as a positive influence overall?  Yes, they help get science news stories out to the wider media, but don't they have some responsibility to make sure that they aren't just a conduit for junk?  Surely they weren't originally intended just to be redistributors of unedited press releases.

3) What are the responsibilities of academic authors, department chairs, deans, etc. when it comes to press releases?  Lord knows, I would not want to have to get permission from a higher-up at my university to speak my mind or point out a cool new result.  However, it doesn't necessarily do anyone a lot of good if people put out press releases and have a media blitz for every little result, let alone the occasional whacko idea.  While universities generally like media mentions of their researchers, CWRU can't be happy about this situation.

If I could do this with electrons....

If they aren't already, these people are going to be swimming (or drowning) in DARPA money.

This is damned peculiar....

There was pretty big hoopla last week about two papers concerning graphene (and it's related material graphene oxide).  In Science, Andre Geim's group reported a remarkable result concerning a membrane made from a "paper" comprising layers of graphene oxide flakes.  This membrane is apparently extremely leak-tight for gases including the notoriously slippery helium, but essentially transparent (!) to the transport of water vapor.  This is very very odd.  The argument made by the authors is that the graphene oxide layers are wet by physisorbed water, which can move across the graphene surface nearly frictionlessly (since graphene itself is hydrophobic - that is, it's nonpolar and doesn't interact particularly strongly with the polar water molecules).  When the water is removed, the layers compress against one another tightly enough that there are no continuous pathways large enough to allow helium diffusion (or they're clogged up with residual adsorbed water).  Assuming this is right, it's pretty cool, and brings to mind the ideal "semipermeable membrane" that's sometimes used as a teaching concept in thermodynamics classes.  (Old joke:  how do you catch a lion in the desert?  A thermodynamicist would take a semipermeable membrane that passes everything except lions, and drag it across the desert to the entrance of a cage.  A mathematician would simply map the exterior of the cage to the interior of the cage.  Etc.)

Now, the other paper that got a decent amount of attention was this one.  The interactions of water with a solid surface are often characterized by a "contact angle", the angle (inside the droplet) with which the water-air interface meets the solid-air interface.  When a droplet on a surface "beads up", that angle exceeds 90 degrees (the surface is hydrophobic), while when a droplet wets the surface well, that angle is much less than 90 degrees (the surface is hydrophilic).  The authors of this paper claim that a monolayer of graphene on a surface leaves the contact angle completely undisturbed (for surfaces where there is not chemical bonding at work between water and the surface).  That's extremely weird, especially in light of the previous paragraph.  You'd have to have a situation where the surface interactions of water with graphene are completely determined by the material under the graphene, not by the graphene itself.  That is, somehow having graphene there doesn't affect the van der Waals interaction much at all.  This is surprising, given past experiments that look at, e.g., the interactions of nanotubes with graphite surfaces, where clearly the van der Waals interaction is nontrivially tied to the graphene geometry, for example.  I have a tough time understanding how the interpretations of both of these papers can be correct, though just because it's unintuitive to me doesn't mean it's not true.

(Bonus question:  can any of the commenters identify the quote that I used for the title of this post?)

Cold atoms, optical lattices, and condensed matter physics

Over the last decade, since this experiment in particular, there has been rapidly growing interest in using optically trapped ultracold atoms, traditionally the tool of what people in the game call "atomic/molecular/optical" or "AMO" physics, to study condensed matter problems.  Using interfering laser beams, it is possible to make a spatially periodic pattern of optical intensity that acts like a spatially periodic potential energy.  Ultracold atoms (they have to be cold so that their kinetic energy is too low for them to fly out of the little potential wells) can be placed in this lattice in a controlled way.  The interactions between the atoms can be tuned using clever approaches, so that the interaction is so large that only one atom will like to sit in each little potential minimum.  It's also possible to tune the overlap of the potential wells to allow tunneling processes so that the atoms can move (virtually and in real space).  With other exceedingly clever modifications, it is even possible to use internal degrees of freedom of the atoms (e.g., nuclear spins), and to introduce effects equivalent to magnetic fields or spin-orbit coupling.

Condensed matter theorists love this stuff - you can actually implement the model problems they've been playing with for ages (e.g., the 2d Hubbard model on a square lattice), and all while maintaining exquisite tunability and control over the microscopic parameters.  Moreover, with spectroscopic techniques, you can probe these systems in real space (no need for diffraction experiments to see the periodic arrangement of atoms - just image them!), and pull out microscopic information (population and energy distributions) that is incredibly hard or impossible to get in solid materials.  These optical lattice systems are particularly great for examining nonequilibrium dynamics in microscopic detail.

This prompts a couple of questions.  First, is this condensed matter physics?  Yes, since the systems being modeled are condensed matter systems - that's how we denote theory, right?  (Empirically, some optical lattice results are now published in the condensed matter section of Phys Rev Letters, so there you go.)  Second, are there condensed matter systems that can't be modeled with these optical lattice methods?  Yes.  For one example, consider a material like VO₂.  First, it's lattice structure is not something readily achievable in an optical lattice.  Second, this material undergoes a spontaneous structural change as a function of temperature, due to coupling between the electrons and the lattice.  In a cold atom system, you would somehow need the optical lattice itself to change depending on the positions of the atoms stored within it - I don't think anyone has figured out how to do such a thing.  I'm sure there are other examples, even in pure single-crystal systems.  Bottom line:  cold atom techniques for studying certain condensed matter problems are amazing and revolutionary, but there are going to be many CM systems that can't be accessed or modeled that way.

"Low energy nuclear reactions" - again.

A person at NASA's Langley Research Center appears in a video touting the great benefits that are going to come with the realization of "low energy nuclear reactions", which is a phrase that is meant to be a bit more general (and a bit less tainted) than "cold fusion".  Let me take care of the preliminaries right away:

• The experimental evidence for any of this stuff remains dodgy at best.  I've explained what most scientists would consider a threshold for reproducibility of a real phenomenon, and this just isn't there.  There's always a "secret sauce" or very particular and idiosyncratic surface treatment; there are equivocal claims about the presence or absence of fusion products and radiation; etc.  (This is the point where a true believer will show up and point out the many documents indexed here, and castigate me for not being sufficiently open-minded.  Let's just take that as read.)
• For this to be correct, much of our knowledge of nuclear processes would have to be in severe need of correction, despite the fact that it works pretty darn well for things like nuclear reactors and the description of how the sun works.
• Just because someone at NASA likes this, or because Brian Josephson likes it, doesn't mean it's automatically real.
• Despite claims to the contrary, physicists would love it if something like this turned out to be true - look at the reaction of most physicists to the superluminal neutrino business.  It'd be the story of the century.  There is not some giant conspiracy of The Establishment trying to suppress this.  Again, look at the neutrino situation:  everyone agrees that such an extraordinary claim requires extraordinary evidence, presented for public scrutiny in detail.    

That being out of the way, I want to comment briefly on the supposed explanation implied by the NASA video, "Method for Enhancement of Surface Plasmon Polaritons to Initiate and Sustain LENR".  The proposed explanation, related to "Widom-Larsen theory", is related a bit to muon-catalyzed fusion.  The muon is a cousin of the electron, but 200 times heavier.  The muon can replace an electron in, e.g., a deuterium molecule, causing the two nuclei to be considerably closer to each other, and enhancing the rate of fusion.  Widom and Larsen propose that some collective coupling between nuclei and collective electronic excitations (plasmons) results in electrons with large effective masses, and that this effective mass enhancement allows "heavy" electrons to catalyze fusion reactions.  This is exceedingly unlikely to be correct, because (to paraphrase Morbo from Futurama), "Effective mass does not work that way!".  At the end of the day, while there are collective excitations of many electrons that act, at condensed matter energy scales, like they are heavy (meaning that their energy increases more slowly as a function of their (crystal) momentum than for a free electron), (1) individual electrons are what participate in things like inverse beta decay, and (2) only a small fraction of the total number of electrons in a metal participate in these "heavy" excitations. 

Again, I'd love it if this were real.  Show me reproducibility that does not require prior belief to buy, and then we can talk.

From around the web

While working on several writing projects simultaneously, I've run across some interesting articles and links.

• Here is an interesting discussion about whether our ordinary metrics are doing a good job at measuring scientific impact (and therefore encouraging the kinds of collaborative behaviors that tend to advance science).  One tricky bit not really addressed here is the challenge of distinguishing when a 12 author paper really involves excellent collaborative work, with everyone contributing to a scientific advance; and when a 12 author paper really represents the work of about 3 people, with others included for contributions (intellectual, financial, or political) of varying small degrees.  
• This is a (slightly ad-laden) compilation of many online lectures related to condensed matter physics.
• Likewise, here are a series of continuing education lectures by Lenny Susskind (who taught me graduate stat mech) on statistical mechanics, and another series on quantum mechanics.  I find it very interesting that these are so clearly organized - he must've put a lot of time into planning them.
• Here is Phillip Gibbs with a great article about why c stands for the speed of light.  I'll admit, I was one of those people he mentions that had read (and naively believed) Asimov's assertion that c stood for the Latin celeritas, meaning "speed".  Guess I need to reconsider!
• More evidence that Elsevier is just evil.  Through lobbyists, they're trying to kill public access to data from publicly funded research if that research has been published in a journal of a for-profit publisher.     
  
• And for fun, here is a place (not the only one, I'm sure) that sells serious computer keyboards - the kind with real clicky metal leaf springs and solid metal backplanes.  I got one of these a couple of years ago and love it.  It reminds me of the best keyboard I've ever used, from an old HP 9000 workstation back in my beginning grad school days.

TOEFL scores

This is my first attempt at using a blogging app for the iPad.  Let's see how it goes....

Over the last few weeks, I've received several emails from foreign students who are would-be applicants to Rice graduate programs, asking me whether I'll be looking for students next year.  In these same emails, the students point out that their TOEFL scores fall below Rice's official cutoff of 90, and ask if they can get in anyway.  For some I know that cutoffs like this seem unfair - that only physics ability should matter in terms of getting into a grad program.  However, we don't set these things just to be arbitrary.  Historically, students who cannot meet that language test criterion have a very hard time - they can't generally be put in front of undergrads to teach, they have difficulty in communicating with their instructors, and often the language barrier is sufficiently severe that there is a tendency to hang out with other students who speak their native language rather than to speak English (a situation that can prolong rather than address the issue).  I have enormous respect for someone motivated and bright enough to go abroad to a foreign country for grad school in a non-native language - I couldn't have done it - but the language rules are there for rational reasons.

Underappreciated papers (not yours)

While doing research, scientists and engineers read (at various levels of depth) many papers.  Every now and then, you come across one that is really great, yet somehow doesn't seem to have received the attention or appreciation it deserves.  I'll pick one here, and hopefully some readers will put their examples in the comments.

One that I like a lot is this paper from Wilson Ho's group at UC Irvine.  Here the authors use a scanning tunneling microscope, and demonstrate that when the tunneling current-voltage characteristic, they get rectification of microwaves.  That is, when microwaves are applied to the tip-sample junction, the result is a dc current proportional to the square of the microwave amplitude and to the nonlinearity (second derivative of I with respect to V) of the tunnel junction.  It's a clean, elegant experiment, with quantitatively accurate comparison of experiment and a simple classical theory - very very nice, and really underappreciated in my view.  

Any suggestions of others?

Tidbits.

First, I have a guest post on the Houston Chronicle's science blog today.  Thanks for the opportunity, Eric.

Second, here is a great example of science popularization from the BBC.  We should do things like this on US television, instead of having Discovery Channel and TLC show garbage about "alien astronauts" and "ghost hunting".

Third, if you see the latest Sherlock Holmes flick, keep an eye out for subtle details about Prof. Moriarty - there's some fun math/physics stuff hidden in there (pdf) for real devotees of the Holmes canon.

Shifting gears

One of the most appealing aspects of a career in academic science and engineering is the freedom to choose your area of research. This freedom is extremely rare in an industrial setting, and becoming more so all the time. Taking myself as an example, I was hired as an experimental condensed matter physicist, presumably because my department felt that this was a fruitful area in which they would like to expand and in which they had teaching needs. During the application and interview process, I had to submit a "research plan" document, meant to give the department a sense of what I planned to do. However, as long as I was able to produce good science and bring in sufficient funding to finance that research, the department really had no say-so at all about what I did - no one read my proposals before they went out the door (unless I wanted proposal-writing advice), no one told me what to do scientifically. You would be very hard-pressed to find an industrial setting with that much freedom.

So, how does a scientist or engineer with this much freedom determine what to do and how to allocate intellectual resources? I can only speak for myself, but it would be interesting to hear from others in the comments. I look for problems where (a) I think there are scientific questions that need to be answered, ideally tied to deeper issues that interest me; (b) my background, skill set, or point of view give me what I perceive to be either a competitive advantage or a unique angle on the problem; and (c) there is some credible path for funding. I suspect this is typical, with people weighting these factors variously. Certainly those who run giant "supergroups" in chemistry and materials science by necessity have more of a "That's where the money is" attitude; however, I don't personally know anyone who works in an area in which they have zero intellectual interest just because it's well funded. Getting resources is hard work, and you can't do it effectively if your heart's not in it.

A related question is, when and how do you shift topics? These days, it's increasingly rare to find a person in academic science who picks a narrow specialty and sits there for decades. Research problems actually get solved. Fields evolve. There are competing factors, though, particularly for experimentalists. Once you become invested in a given area (say scanned probe microscopy), this results in a lot of inertia - new tools are expensive and hard to get. It can also be difficult to get into the mainstream of a new topic from the outside, in terms of grants and papers. Jumping on the latest bandwagon is not necessarily the best path to success. On the other hand, remaining in a small niche isn't healthy. All of these are "first-world problems", of course - for someone in research, it's far better to be wrestling with these challenges than the alternative.

students and their mental health

There was an interesting article earlier this week in the Wall Street Journal, on mental health concerns in college students. It's no secret that mental illness often has an onset in the late teens and early twenties. It's also not a surprise that there are significant stressors associated with college (or graduate school), including being in a new environment w/ a different (possibly much smaller) social support structure, the pressure to succeed academically, the need to budget time much more self-sufficiently than at previous stages of life, and simple things like lack of sleep. As a result, sometimes as a faculty member you come across students who have real problems.

In undergrads, often these issues manifest as persistent erratic or academically self-destructive behavior (failure to hand in assignments, failure to show up for exams). Different faculty members have various ways to deal with this. One approach is to be hands-off - from the privacy and social boundaries perspective, it's challenging to inquire about these behaviors (is a student just having a tough time in college or in a particular class, or is a student afflicted with a debilitating mental health issue, or are is the student somewhere on the continuum in between). The sink-or-swim attitude doesn't really sit well with me, but it's always a challenge to figure out the best way to handle this stuff.

In grad students, these issues can become even more critical - students are older, expectations of self-sufficiency are much higher, and the interactions between faculty and students are somewhere between teacher/student, boss/employee, and collaborator/collaborator. The most important thing, of course, is to ensure that at the end of the day the student is healthy, regardless of degree progress. If the right answer is that a student should take time off or drop out of a program for treatment or convalescence, then that's what has to happen. Of course, it's never that simple, for the student, for the advisor, for the university.

Anyway, I suggest reading the WSJ article if you have access. It's quite thought-provoking.