Condensed concepts

What kind of theory paper to I enjoy? Here are some personal tastes - "simple" enough I can understand it - physical insight - some analytical results - some pretty pictures that illuminate This week I read the following paper which I consider nicely meets these criteria. Band touching from real-space topology in frustrated hopping models Doron L. Bergman, Congjun Wu, and Leon Balents The quantum spin antiferromagnetic Heisenberg model on the kagome lattice attracts a lot of attention because it may have a spin liquid ground state, for spin-1/2 and spin 1 . This is arguably driven by the large spin frustration. A reflection of this frustration is that the classical model has a non-zero entropy at zero temperature due to a manifold of degenerate states. For this reason, the kagome lattice is sometimes said to be "maximally frustrated". This is in contrast to the triangular lattice for which their is a unique classical ground state and the spin-1/2 mode

On friday I am giving the UQ Physics Department colloquium on mental health issues for scientists. The talk may be similar to one I gave a few years ago. I will update my talk incorporating s ome recent reading and the articles below. A recent Editorial in Nature declared Time to talk about why so many postgrads have poor mental health  An outpouring on Twitter highlights the acute pressures on young scientists. [I thank Tanglaw Roman for bringing the editorial to my attention. I never look at luxury journals unless someone refers me to a specific article.] The Editorial was in response to the Twitter response to an article in a baby Nature Evidence for a mental health crisis in graduate education Poisonous science: the dark side of the lab  The bullying and subsequent suicide of a talented Ivy League scientist exposes ugly truths about the cruelty and dysfunction at the heart of academic science Mindfulness won't fix bad management It also conveniently shifts th

I watched Ph.D Movie 2: Still in Grad School, which is based on the legendary Ph.D comics, written by Jorge Cham. It is worth watching as it is quite funny. On the other hand, some of the caricatures are getting a little too close to reality.... While on the funny side of science, my wife and I have been enjoying watching Young Sheldon . I am a Big fan of The Big Bang Theory, but was not sure whether this new show would be as good. This was partly influenced by a moderately negative review in the New York Times (albeit based on one episode). I disagree as I think that both shows do have an interesting cast of characters. On the other hand, Young Sheldon does not have as much science as TBBT, at least for the first six episodes that I have seen. Here Schrodinger's cat gets discussed.

The physics department at UQ has just advertised for a new faculty member in experimental condensed matter. The advert is here. There is also a junior faculty position available in astrophysics. Aside. The picture is of Lake McKenzie (no relation) on Fraser Island, which I just visited on mid-semester break.

Which scientist had the greatest political influence of all time? the greatest influence on government policy? Oppenheimer? Any suggestions? Not Schrodinger, but arguably Frederick Lindemann. Until last week I had barely heard of Lindemann. I knew of the Lindemann criterion for estimating the melting temperature of a solid. At Oxford, I had been in the Lindemann building (the front of the Clarendon lab) many times, but had not bothered to find out who Lindemann was. Last week I listened to a fascinating podcast by Malcolm Gladwell, The Prime Minister and the Prof , that recounts Lindemann's long relationship with Winston Churchill. The podcast draws heavily on two sources (interestingly both written by physicists). The first source is three lectures that C.P. Snow [of two cultures fame] gave at Harvard in 1960, and published as Science and Government . The second source is a book, Churchill's Secret War: The British Empire and the Ravaging of India during World War I

It is fun to come up with clever names for new physical phenomena: quark, big bang, Janus , slepton,  chromodynamics, inflation,  squashon,  ... There is an amusing article by David Mermin about how he managed to get boojum   accepted as a scientific term. Can you think of others? What is a good synonym for something that has both good and bad qualities? A curate's egg? I was wondering about this because of thinking about a metal that is a mixture of a good metal and a bad metal. This is relevant close to an orbital-selective Mott transition. There it may be possible to have multiple Fermi liquids (associated with multiple bands) at low temperatures with different coherence temperatures. For example, this does occur in strontium ruthenate.   As a result, when the temperature is increased one can enter a state in which one of the bands has coherent quasi-particles (and a well-defined Fermi surface) and another does not, i.e. it is a bad metal. A relevant paper is Observat