Thursday, October 5, 2017

Which single verb describes the mission of universities?

Think!

Research is all about thinking about the world we live in; whether it is genetics, cosmology, literature, engineering, economics, ...
Reality is stratified and one observes different phenomena in different systems. As a result, one needs to think in distinct ways in order to develop concepts, laws, and methodologies for each strata.
Note that thinking is central to experiments: thinking how to design the experiment and apparatus, and how to analyse the data produced and relate it to theory.
This is why we have disciplines. Each discipline involves a disciplined way of thinking.

Teaching is all about helping students learn how to think.
For specific disciplines, it involves learning how to think in a particular way.
Thinking like a condensed matter physicist is an art to learn.
Similarly, thinking like an economist is a unique way of thinking.

If this is the mission of modern universities are they successful?
On one level they have been incredibly successful.
Almost all the disciplines and knowledge we have were created in universities.
These ways of thinking have been incredibly productive and revealed things we might never have anticipated or dreamed of. Whether it is the genetic code, quantum field theory, game theory, or studies of ancient histories and cultures, ....

Furthermore, universities have really taught many students to think critically and creatively, not just about academic matters. University graduates have used their thinking skills in constructive ways, whether in inventions, starting companies, journalism, politics, philanthropy, ...
It should be acknowledged that this education does not just occur in the classroom but in informal contexts and involvement in student clubs and societies.

However, when you consider the resources that have been expended globally, both in teaching and research, you have to wonder whether universities are now failing at their mission.
This is reflected in a sparsity of critical thinking on many levels and in many contexts.

In the Majority World, universities try to mimic Western ones, at the superficial level of structures and curriculum. However, largely they focus on rote learning and not questioning teachers. This tragedy is captured with humour in my favourite Bollywood movie scene. Not only are students not taught how to think, they are actually taught not to think at all!

Yet, Elite universities now have a lot to answer for. The administration has become decoupled from the faculty and so we have metric madness and mindless marketing. Many of the statements or decision making processes (e.g. ignoring uncertainties, listing journal impact factors to 4 significant figures or cherry picking data to enhance the "ranking" of an institution) would be not be allowed in a freshman tutorial or lab.
Yet faculty are not without fault. Critical analysis will be avoided if publishing in a luxury journal is on the horizon. Then there is the hype of faculty about their latest research, whether in grant applications or public relations.

There are countless other ideas about what the mission of the university should be: training graduates for high paying jobs, wealth creation, enhancing national security, elite sports, industrial research, creating good citizens, ...

Many of these alternative missions are debatable, but regardless, they should be subordinate to the thinking mission.

Key to the thinking mission is academic freedom. Faculty and students need to be free to think what they want about what they want (within certain civil and resource constraints). Political interference and commercial interests inhibit such thinking.
It is interesting that Terry Eagleton, considers that the primary mission of universities is to critique society.

I thank Vinoth Ramachandra for teaching me this basic but crucial idea.

Thursday, September 28, 2017

Emergence in the Game of Life

How do complex structures emerge from simple systems?
How do you define emergence?

Conway's Game of life is a popular and widely studied version of cellular automata. It is based on four simple rules for the evolution of a two-dimensional grid of squares that can either be dead or alive. What is amazing is that distinct patterns: still lifes, oscillators, and spaceships can emerge.

Gosper's glider gun is shown below.


What does this have to do with strongly correlated electron systems?
The similarity is that one starts with extremely simple "rules": a crystal structure plus Coloumb's law and the Schrodinger equation (Laughlin and Pines' Theory of Everything) and complex structures emerge: quasi-particles, broken symmetry states, topological order, non-Fermi liquids, ...

Recently, Sophia Kivelson and Steven Kivelson [daughter and father] proposed the following definition:
An emergent behavior of a physical system is a qualitative property that can only occur in the limit that the number of microscopic constituents tends to infinity.
I think this would mean the properties above would not be classified as emergent. I am not sure I agree. I think I still prefer older broader definitions such as that of Michael Berry in terms of singular expansions or that of P. Luisi.
The definition also disagrees with Michael Polanyi, who argued that language and grammar are emergent.

Saturday, September 23, 2017

My ambivalence to anonymous blog comments

Although this blog has a wide readership one thing it struggles with is to attract many comments, and particularly much back and forth discussion. Sometimes people tell me that this is just because it is not provocative or controversial enough.

A while ago I changed the settings to allow anonymous comments and this has led to an increase in comments which is encouraging. However, I do have some ambivalence about this. 

Ideally, any comment and opinion should be judged on the merits of its content not based on who is giving it. We should beware of arguments from authority. On the other hand, that is not the way most of us think and act. We do give some weight to the author. For example, an anonymous commenter says "I am a physicist and I am a climate change skeptic" it does not have the same weight as the opinion of a respected physicist who has relevant expertise.

I am also concerned that people are not willing to take the risk of being publically identified with their views. This does not just reflect on the commenter but also reflects poorly on the scientific and academic community. Why are people so hesitant? Is the community so intolerant of controversial views? 
Here I should say I am very sympathetic to some peoples nervousness. At least twice, I suggested to younger colleagues who did not have permanent jobs that they delete specific comments they made on the blog that were critical of the "establishment".

I welcome discussion.

Nevertheless, please don't let my ambivalence stop you making comments.

Wednesday, September 20, 2017

An ode to long service leave


Australia has many unique things besides kangaroos and koalas. Long service leave (LSL) is a generous and egalitarian feature of the "welfare" state. After ten years working for the same employer [or the same sector such as government universities] an employee is granted three months fully paid vacation. (The exact terms and conditions vary slightly between states and employers). LSL is available to all full-time employees, regardless of whether they are janitor or CEO. This is in addition to four (plus) weeks of annual leave and for faculty in addition to "sabbaticals" [called Special Studies Program in my university]. If an employee resigns any unused balance is "cashed out".

University faculty work hard and some are workaholics. Many don't even take their allotted annual vacation, let alone LSL. Balances carry over each year and so some faculty have large balances. The "accountants" (who basically run the university) don't like this because LSL is a "liability" on their spreadsheets. If all of the faculty with large balances resigned at the same time the university would have to "cash" them out and there would be no money available to hire replacements for several months. Who would do the teaching, research, and admin? The university would grind to a halt....
However, this is pretty silly because the likelihood of massive simultaneous resignations of this particular group is extremely unlikely. When an individual does resign one can always wait a while to rehire and others absorb their "workload". Furthermore, this is likely to happen anyway, because replacing people, particularly senior ones, takes a while anyway.

Nevertheless, because the accountants rule, faculty are put under pressure to take LSL and recreation leave (vacation) if they have large balances. Specifically at UQ, when a staff member has a balance of more than 15 weeks of LSL they can be "directed" to take leave to reduce their balance. In fact, we now receive emails from the Executive Dean telling us that in our annual appraisal (performance review) we have to discuss the issue and come up with a written plan of how we will reduce our leave balance. On one level this is fine. However, on another level, this just reflects skewed priorities. We do not get explicit instructions and reminders (and threats) to discuss and plan how to engage better with students, set more challenging assessment, focus on research quality rather than quantity, be critical about metrics, ...

So what do people do with their LSL?
Is it actually in the best interests of the university for people to take it?

Here are some specific examples I am aware of.

1. Keep going to your office and doing research but no teaching or admin. The problem is that legally the university does not want this as they don't have liability insurance for you while on campus.

2. Treat it as a sabbatical and visit another institution. The problem is that you are on vacation as far as the university is concerned and so cannot use grant money for travel.

3. Have a long vacation and come back refreshed and motivated.

4. Have a great vacation and decide to retire early.

5. Spend the time looking for a new job. During this time many things and important decisions are left in limbo, before the employee eventually leaves.

Although most of these options may be good for the employee, they may not be the best thing for the employer. Thus, in the bigger scheme of things, forcing people to take LSL is debatable.
There is more to an institution than spreadsheets....

Having said all this I should say that I am really enjoying my LSL. The picture below is from a kayak trip in the San Juan Islands, near my mother-in-law's house, which also features sunsets such as above.



Wednesday, September 13, 2017

The rise of BS in science and academia

I never thought I would write a blog post with such a word in it.

In today’s Seattle Times there is an editorial about fake news and an opinion piece, How to fine-tune your BS meter, by Jevin West.
At the University of Washington, West and Carl Bergstrom, have started a course entitled, Calling BS: Data reasoning for the digital age.
West states:
Our philosophy is that you don’t need a Ph.D. in statistics or computer science to call BS on the vast majority of data bullshit. If you think clearly about what might be wrong with the data someone is using and what might be wrong about the interpretation of their results, you’ll catch a huge fraction of the bullshit without ever going into the mathematical details.  
Unfortunately, this applies to science as much as to Fake News. On his blog, Peter Woit discusses the rise of Fake Physics.
Science is in trouble when the word I most often hear associated with the name of a particular Ivy League science Professor is BS. Furthermore, in many contexts, I hear people dismiss specific papers,
particularly that appear in luxury journals, as “just BS”.

A good question is what criteria should we use to distinguish between uncritical enthusiasm, marketing, hype, and BS?

I first thought of writing a post on this subject when I encountered this video clip from CNN.
I thought, “Wow! Who is this commentator?” Maybe I should have known, but I learned that Fareek Zakaria has quite a following, a Ph.D. in Political Science from Harvard, and is rightly viewed as a serious commentator, regardless of whether you agree with his political leanings.
The commentary is based on a number one New York Times bestseller, On BS  by Harry Frankfurt, a distinguished Princeton philosopher.

Saturday, September 2, 2017

Debating emergence and reductionism

As part of a TV documentary, Why are we here? produced by Ard Louis and David Malone there is a nice series of interviews where emergence is discussed by George Ellis, Peter Atkins, and Denis Noble.
I can't seem to embed the interviews here and so have put in links to short clips.

George Ellis discusses the difference between weak and strong emergence and his attitude to each.

In separate clips, Denis Noble discusses emergence  and reductionism in biology.

Peter Atkins, a hardcore reductionist, IMHO does not seem to seriously engage with the issue.

Thursday, August 31, 2017

Did Schrodinger's cat explore Tolkien's garden?

In 1935 Schrodinger wrote his famous paper (with the cat) introducing the term entanglement, in response to the Einstein-Podolsky-Rosen paper published earlier that year.

When Schrodinger wrote the paper he was living in a house on Northmoor Road, Oxford. This was the same house where Schrodinger learned he had been awarded the Nobel Prize.


I recently learned some fascinating historical trivia.
Schrodinger was a neighbour of J.R.R. Tolkien, who during that time was finishing up work on The Hobbit.

It would be nice to see this landmark honoured, such as the one on Tolkien's house. However, it seems Schrodinger's house does not meet the criteria of Oxfordshire Blue Plaques Board, because he lived there for three years, less than the required minimum of five years.


Another option would be a plaque of the Institute of Physics, such as this one.


Tuesday, August 29, 2017

The most important concept in economics is emergence

This is not based on the hubris of a condensed matter physicist, but rather the claim of three economists in an Econtalk podcast,  where Don Boudreaux, Michael Munger, and Russ Roberts discuss Emergent Order. For example, Boudreaux states
the notion of spontaneous order is indeed the most profound, single most profound insight of good economics. It remains the insight that is most elusive to the general public. Sadly, it remains an insight that is elusive to a lot of professional economists these days.
The discussion centres around Robert's poem, "Its a wonderful loaf", the website for which has an animation of the poem and a nice list of related resources. The key idea is that free markets lead to an emergent order of prices, division of labour, and matching of supply and demand. This order is Adam Smith's "invisible hand" that guides the economy. It is actually "bottom up", not top down. Many of the ideas discussed are those originating with F. A. Hayek, in the context of not just economics but also in social and political philosophy. A summary I found helpful of Hayek's ideas is in a recent paper by Paul Lewis.

There is some disagreement between the three participants about whether the relevant terminology is "spontaneous order", "emergent order", or "self-organising system", but I did not find that particularly  insightful.

One weakness of the discussion is that the three economists all have libertarian sympathies [i.e. they believe less regulation of markets the better] and there is an undercurrent in the discussion that this is justified by an emergent perspective. However, there are some really good comments on the podcast blog that eloquently argue against this and discuss the complexity of finding the right balance between free markets and government regulation. The comments are worth reading.

I thank my economist son for bringing the podcast to my attention and listening to it with me.

Tuesday, August 22, 2017

Managing my mental health

I have received positive feedback about previous posts about mental health and so I share some recent experiences in the hope it may be helpful to some.

I have had three significant times where my mental health deteriorated to the point I could not function “normally”. The first was during my Ph.D and the second about 15 years ago. The most recent experience was roughly six months ago. Here are a few things I learnt [or re-learnt] from this last experience.

The decline is often gradual and not perceived or denied.
It is like the proverbial frog in boiling water. It does not notice how the temperature is increasing and never jumps out.

The longer you wait to address the issue the slower the recovery.
Don't think things will get better on their own.

Mental illness is irrational.
That's the point. When I now think about some of the thoughts and perceptions that seemed “real” and “true” to me 6-12 months ago it is sad and bizarre.

Relapse is not uncommon.
If you have had previous incidents and recovered don't think it will never happen again.

Complexity.
There is high causal density. Diverse circumstances and stresses, whether work, family, social, or relational, may all contribute to varying degrees. Hence, the most effective solutions and treatments are likely to be multi-faceted.

Professional help.
Get it sooner than later.
Don’t self-diagnose.
Getting help also relieves the burden on family and friends.

Aside: In Australia (which is blessed with a reasonable national health scheme) a GP doctor can prescribe a mental health treatment plan which entitles the patient to subsidised sessions with a psychologist or psychiatrist.
[Mind you due to bureaucratic errors it took several phone calls and two visits to the Medicare office before the paperwork was actually processed properly…].

I went to see the same psychologist who I saw 15 years ago. This was helpful because she knew my history and issues. Also, I trusted her and knew she could help. I think one simple but significant value of these visits is the accountability to be making changes and addressing issues.

Medication.
It does not work for everyone. Some people have bad side effects.
There is a debate about whether antidepressants are over-prescribed. Medication should not be a substitute for talking therapies and lifestyle changes. However, medication sure works for me! After several years without, I went back on a small dose of an antidepressant. I still find it amazing the difference it makes. Just a little fine tuning of the brain chemistry....

Mindfulness.
Some of these meditation exercises may seem like New Age mumbo jumbo. However, when I did them 15 years ago, I learnt for the first time in my life to control my thoughts.
Again, going back to them really helped.

You will get better.
When you are physically ill, whether from flu or surgery, life can seem pretty bleak and it is hard to remember what normal was, and you may wonder whether you will ever get better. It is the same with mental illness. With appropriate treatment, healing usually does occur. But hope and patience are key.

Postscript (14 October).
Things are really getting better.
Thanks for the kind messages from people, including those who have shared some of their own stories.
It is encouraging that the President of University of British Columbia, Santa Ono, is speaking about his own struggles.

Friday, August 18, 2017

From instrumentation to climate change advocacy

I learned a lot from reading In the Eye of the Storm: The Autobiography of Sir John Houghton (with Gill Tavner). He is arguably best known for being the lead editor of the first three reports of the IPCC (Intergovernmental Panel on Climate Change). He started his scientific life as an atmospheric physicist at Oxford. Here are a few things that struck me.

The value of development of new instruments.
At Oxford Houghton was largely involved in finding new ways to use rocket based instruments measure the temperature and composition of the atmosphere at different heights. These were crucial for getting accurate data that revealed the extent of climate change and understanding climate dynamics. It was good for me to read this. As a theorist, I am often skeptical or at least unappreciative of the value of developing new instruments. I think it is partly because I have heard too many talks about instrument design where it really wasn't clear they were going to generate useful and reliable information, particularly that could be connected to theory.

A reluctant administrator.
I think the best people for senior management are those who don't want the job. The worst are those who desperately want the job. It is interesting to see that Houghton was quite reluctant to leave Oxford when he was asked to be director of Rutherford-Appleton Lab. Then he wanted to go back to Oxford but was persuaded to become head of the Meteorological Office. It is also refreshing to see how he pushed back against some of the "management" nonsense that people wanted to impose on the organisations that he led.

Rigorous peer review at the IPCC.
Just because something is peer reviewed does not mean it is true. However, when there is an overwhelming consensus about some issue in peer-reviewed literature, we can high confidence it is true. Furthermore, at the IPCC there was really a double layer of peer review. The reports were based on reviews of the peer-reviewed literature. Every sentence in the reports was debated and ultimately voted on by a committee of leading scientists with relevant expertise. It is very hard to get scientists to agree on anything. However, when they can agree it means there must be a high probability it is true.

Dirty tactics of denialists.
There are a few stories about the different antics of "observers" at IPCC meetings who worked tirelessly to get IPCC to dilute their reports and sow doubt. Unfortunately, Federick Seitz features along with the lawyer/lobbyist Don Pearlman, who worked for the Global Climate Coalition.

Gracious public engagement.
The book describes how Houghton has worked hard to engage with climate change denialists, particularly among Conservative Christian leaders in the USA.

Finally, the book makes a strong case for concerted action on climate change. The most striking figure in the book was the map of Bangladesh showing how much will go under water, with just a one-metre rise in sea level. As often the case it is the poor that suffer the most.


Wednesday, August 9, 2017

Subtle paths to effective Hamiltonians in complex materials

Many of the most interesting materials involve significant chemical and structural complexity. Indeed, it is not unusual for a unit cell for a crystal to contain the order of one hundred atoms.
Yet, for a given class of materials, one would like to find an effective Hamiltonian involving as few degrees of freedom and parameters as possible.

Following Kino and Fukuyama, twenty years ago I argued that the simplest possible effective Hamiltonian for a large class of superconducting organic charge transfer salts was a one-band Hubbard model on an anisotropic triangular lattice at half filling.
It seemed natural to then argue that the relevant model for the spin degrees of freedom in the Mott insulating phase is the corresponding frustrated Heisenberg model with spatial anisotropy determined by the anisotropy in the tight-binding model.

However, it turns out this is not the case.
There are some subtle quantum interference effects that I overlooked in the "derivation"  of these effective models, leading to a different spatial anisotropy.
This is shown by some of my colleagues in a nice recent paper, accepted for PRL.

Dynamical reduction of the dimensionality of exchange interactions and the "spin-liquid" phase of κ-(BEDT-TTF)2X 
B. J. Powell, E. P. Kenny, J. Merino


This raises questions about what the relevant effective Hamiltonian is for the metallic, superconducting, and (possibly) ferroelectric phases.

The paper's significance goes beyond organic charge transfer salts to the general problem of finding effective Hamiltonians in complex materials.

Similar interference effects have been found to arise in quite a different class of materials.

Heisenberg and Dzyaloshinskii-Moriya interactions controlled by molecular packing in trinuclear organometallic clusters 
B. J. Powell, J. Merino, A. L. Khosla, and A. C. Jacko

This also reminds me of subtleties (and debates) that occur in the Zhang-Rice "derivation" of the t-J model from a three-band Hubbard model.

Saturday, August 5, 2017

Who was the greatest theoretical chemist of the 19th century?

Dimitri Mendeleev, who proposed the periodic table of the elements, purely from phenomenology and without quantum mechanics!
He even successfully predicted the existence of new elements and their properties.

A friend who is a high school teacher [but not a scientist] asked me about how he should teach the periodic table to chemistry students. It is something that students often memorise, especially in rote-learning cultures, but have little idea about what it means and represents. It makes logical sense, even without quantum mechanics. This video nicely captures both how brilliant Mendeleev was and the logic behind the table.



A key idea is how each column contains elements with similar chemical and physical properties and that as one goes down the column there are systematic trends.
It is good for students to see this with their own eyes.
This video from the Royal Society of Chemistry shows in spectacular fashion how the alkali metals are all highly reactive and that as one goes down the column the reactivity increases.



The next amazing part of the story is how once quantum theory came along it all started to make sense!

Tuesday, August 1, 2017

The role of the Platonic ideal in solid state physics

In the book Who Got Einstein's Office?, about the Institute for Advanced Study at Princeton, the author Ed Regis, mocks it as the "One True Platonic Heaven" because he claims its members are Platonic idealists, who are interested in pure theory, and disdain such "impurities" as computers and applied mathematics.


This stimulated me to think about the limited but useful role of pure mathematics, Platonic idealism, and aesthetics in solid state theory. People seem particularly excited when topology and/or geometry plays a role.

The first example I could think of is the notion of a perfect crystal.

Then comes Bloch's theorem, which surely is the central idea of introductory solid state physics.

Beautiful examples where advanced pure maths plays are role are
Chern-Simons theory of edge states in the Quantum Hall Effect
and topological terms in the action for quantum spin chains, as elucidated by Haldane.

As I have said before I think topological insulators is a beautiful, fascinating, and important topic. However, I am concerned by the disproportionately large number of people working on the topic and the associated hype. I wonder if some of the appeal and infatuation is driven by Platonic idealism.

For a classic example of how Platonism leads to imperfect theory is Kepler's Platonic solid model of the Solar System from Mysterium Cosmographicum (1596).


Good theory finds a balance between beauty and the necessity of dirty details.

Can you think of other examples where Platonic idealism plays a positive role in condensed matter theory?

Saturday, July 22, 2017

Entering the strange world of Kurt Godel

The picture below is of Godel's rotating universe. It represents an exact solution to Einstein's gravitational field equations and has the strange property of closed timelike curves (i.e. one can travel into the past!). This mathematical solution was found by Kurt Godel while he was employed by the Institute for Advanced Study at Princeton.


I think I first encountered this picture in my final undergraduate year in the classic book, The Large Scale Structure of Space-Time by Hawking and Ellis, while working on a research project in general relativity.

Godel's universe is just one example of the fascinating science and stories recounted in the book
Who Got Einstein's Office? Eccentricity and Genius at the Institute for Advanced Study by Ed Regis, first published 30 years ago.

I only read the book this past week and loved it. It is a captivating blend of science, mathematics, personalities, history, philosophy, humorous anecdotes, gossip, eccentricities ...
I was so captivated that I read it during two situations I would not normally read something so "heavy": during a long flight [normally I watch reruns of The Big Bang Theory or Upper Middle Bogan [need to laugh!] or recently a Warren Buffett documentary... sorry better not mention that again...], and during "down time" in the evening after a busy day.

Regis nicely describes the continuum hypothesis, Einstein-Podolsky-Rosen (EPR) "paradox" in quantum theory, von Neumann machines, cellular automata, the Bourbaki seminar, parity violation, the solar neutrino problem, fractals, the stability of matter, ...

The personalities covered include Godel, Einstein, Herman Weyl, John von Neumann, J. Robert Oppenheimer, Freeman Dyson, T.D. Lee,  C.N. Yang, Andre Weil, John Bahcall, Stephen Wolfram, Ed Witten, .....

It is amazing how much Regis packs into less than 300 pages (in a paperback).

The tragic mental health problems of Godel are described in a sensitive manner.

One pathetic story concerns the endless quibbles of T.D. Lee and C.N. Yang.
(Aside: They actually did their Nobel Prize winning work on parity violation at the IAS. This is in contrast to the countless Nobel laureates who at one time have been affiliated with the IAS but did not do their prize work there.)
Lee and Yang (or is it Yang and Lee?) argued constantly about the order in which their names should be listed, not just as co-authors, and at the Nobel ceremony, but even in newspaper and magazine articles about them. Furthermore, it is crazy to read the wildly different and self-serving accounts of certain concrete events. Great scientists are all too human ......

Some people consider the book is a bit of a "hatchet" job and has a mocking tone that paints the IAS in a poor light and questions its value and existence. I would not agree. I think it does show that the IAS has produced a lot of important scholarship. Regis does raise some important questions I mention below. But, I did think that he did refer to the IAS as "the One True Platonic Heaven" too many times.

Regis is implicitly critical of the fact that there is very little interaction between different research groups and disciplines within IAS. However, there is one important story he missed: when Freeman Dyson and the number theorist Hugh Montgomery were introduced at tea at the IAS and they made a connection between random matrix theory (quantum physics) and zeros of the Riemann zeta function.

Some questions the book raises for me include:

Can you really "manage" genius?

How do you create an institutional environment that increases the likelihood of truly great discoveries and scholarship?

What is the best way to hire "great" people?

What is a good mix of young and old staff?

What is a good mix of permanent faculty, postdocs, and short term senior visitors?

When is the absence of students in a research institute good or bad?

When is the absence of experimentalists in an institution bad/good for theoretical physics?

How do you foster a healthy synergy between pure mathematics and theoretical physics?

How might you foster some constructive interaction between distinct disciplines: philosophy, mathematics, theoretical physics, economics, history, ....?

Here is Feynman's perspective (partly quoted in the book):
I don't believe I can really do without teaching. The reason is, I have to have something so that when I don't have any ideas and I'm not getting anywhere I can say to myself, "At least I'm living; at least I'm doing something; I am making some contribution" -- it's just psychological. 
When I was at Princeton in the 1940s I could see what happened to those great minds at the Institute for Advanced Study, who had been specially selected for their tremendous brains and were now given this opportunity to sit in this lovely house by the woods there, with no classes to teach, with no obligations whatsoever. These poor bastards could now sit and think clearly all by themselves, OK? So they don't get any ideas for a while: They have every opportunity to do something, and they are not getting any ideas. I believe that in a situation like this a kind of guilt or depression worms inside of you, and you begin to worry about not getting any ideas. And nothing happens. Still no ideas come. 
Nothing happens because there's not enough real activity and challenge: You're not in contact with the experimental guys. You don't have to think how to answer questions from the students. Nothing!
Governments have less and less interest in "research for its own sake" and "without constraints" [hallmarks of the IAS]. However, there is an increasing number of generous and wealthy philanthropic organisations who are very interested. These are important questions for them.

Although I lived in Princeton for four years around the time the book was being written I only recall going inside "the Brain Farm" [as a friend called it] once, and that was for a music concert. Nevertheless, I spent many pleasant hours walking, jogging, bird watching, and skiing in the beautiful woods located behind the IAS.

I thank Ben Powell for a conversation about the IAS, stimulating me to remember I had inherited a copy of the book from my parents.

I welcome thoughts on any of the questions and any good IAS stories...

Sunday, July 16, 2017

Lessons for universities from Warren Buffett

This is not about managing university endowments!

On a recent flight I watched the fascinating HBO documentary, Becoming Warren Buffett.
He may be one of the richest people in the world, and perhaps the most successful investor of all time. However, what is much more striking than his success is how he got there: in a completely counter-cultural (or iconoclastic) way.

Here a few lessons that I think are particularly relevant to universities as they struggle with their identity, purpose, and management.

Focus.
Several times Buffett and some of his admirers emphasised this. Good research of companies and understanding the market requires considerable focus. You can't be doing lots of different things or jumping into the latest fad. Universities need to focus on teaching and research. Faculty need to focus on just a few things they can do well.

The long view.
Buffett does not "play" the market. He finds companies that are undervalued or have enduring market share and keeps their stocks for decades.
Similarly, quality and innovative research requires large and long time investments. Rarely do things happen quickly.

Personal relationships are key.
Buffett has had a long and fruitful relationship with Charlie Munger. Furthermore, it seems within Berkshire Hathaway, the personal relationships between employees and with companies they invest in are key. If people can't get along or management is heavy handed or autocratic, long term productivity is unlikely.

Cut all the bureaucratic and management BS.
I might have misheard it but I got the impression that Berkshire Hathaway did not really have an HR or marketing department. Their reputation is their marketing. HR is worked out on a personal level.

It is all about the quality of the product.
Buffett looks for companies that have a quality product for which there is likely be long term demand. It does not matter how much slick marketing there is. In the long term, all that matters is the product. Similarly, universities need to focus on the quality of their "product": their graduates, and the content of the research they produce in papers and books.

Reputation is central.
Buffett preserves his and looks carefully at the companies he invests. Furthermore, a good reputation takes decades to establish but can be lost in days (e.g. through scandal). Universities with a good reputation should really think twice before they "cut corners"  to boost revenue [e.g. by offering expensive Masters degrees by coursework to international students but actually involve students taking undergraduate classes].

Integrity and leadership by example.
This is an important component of Buffett's reputation. Just one example is how he released his tax returns during last years US Presidential campaign. University managers who take/demand ridiculous salaries should think about how that undermines their ability to lead.

Jobs should be fun.
Buffett keeps working because he is having fun not because he wants to make more money. Universities should carefully consider whether they are creating an environment that employees enjoy.

I was also struck by Buffett's generous philanthropy, his concern about economic inequality, and that it would be hard to find a billionaire who was anymore the antithesis of Trump.

Thursday, July 6, 2017

Are theoretical physics and chemistry amenable to online collaboration?

Last week at UQ we had a very nice mathematics colloquium, "Crowdsourcing mathematics problems" by Timothy Gowers.
He first talked about the Polymath project, including its successes and marginal contributions.
He then talked about a specific example of a project currently underway on his own blog, concerning transitive dice. This was pretty accessible to the general audience.

This is where a well defined important problem is defined on a blog and then anyone is free to contribute to the discussion and solution. A strength of this approach is that it makes use of the complementary strengths, experience, and expertise of the participants. Specifically, solving problems includes:
  • selecting a problem that is important, interesting, and potentially ripe for solution
  • defining the problem clearly
  • breaking the problem down into smaller parts including conjectures
  • sketching a possible heuristic argument for the truth of the conjecture
  • giving a rigorous proof of the conjecture
  • finding possible counter-examples to the conjecture
  • connecting the problem to other areas of mathematics
This can be efficient because dead ends and mistakes are found quicker than someone working in isolation. 
People are more motivated and engaged because they are excited to be working on something bigger than themselves and what they might normally tackle. And they enjoy the community.
What about assigning credit in such group work? There is a clear public record of who has contributed what. Obviously, this does not work for bean counters looking at traditional metrics.
This approach mostly attracts senior people who are secure in themselves and their career stage and more interested in solving problems than getting individual credit.

The cultural differences of pure mathematics and physics was striking. The talk was given on whiteboards and blackboards without notes. No powerpoint! The choice of research problems was purely based on curiousity, not any potential practical value or the latest fashion. It is fascinating and encouraging that the pure mathematics community is still "old school" with the focus on quality not quantity.

Aside: Gowers is also well known for initiating a boycott of Elsevier journals.

Now, my question. 
What is stopping theoretical chemistry and physics from such a "crowd sourcing" approach? 
Is it that the problems are not amenable? 
Or is it largely that we are too driven by a system that is fixated on individual credit?

Monday, July 3, 2017

A molecular material and a model Hamiltonian with rich physics

Some of my UQ colleagues and Jaime Merino have written a series of nice papers inspired by an organometallic molecular material Mo3S7(dmit)3. They have considered possible model effective Hamiltonians to describe it and the different ground states that arise depending on the model parameters.
There is a rich interplay of strong correlations, Hund's rule coupling, spin frustration, spin-orbit coupling, flat bands, and Dirac cone physics.
Possible ground states include some sort of Mott insulator, a Haldane phase, semi-metal, ...

A good place to start is the following paper
Low-energy effective theories of the two-thirds filled Hubbard model on the triangular necklace lattice 
C. Janani, J. Merino, Ian P. McCulloch, and B. J. Powell

The figure below (taken from this paper) shows some of the molecular structure and some of the hopping integrals that are associated with an underlying decorated honeycomb lattice.


This model could be called kagomene, because it interpolates between the kagome lattice and the honeycomb lattice (graphene). The figure below is taken from this paper, which uses DFT and Wannier orbitals to estimate the tight-binding parameters and the spin-orbit coupling. Interaction driven topological insulator states are possible on this lattice.



There are a few things that are not "normal" about the physics, arising from the 4/3 band filling and the molecular orbitals that are delocalised over the triangles. Specifically, the orbital degeneracy does not arise from atomic orbital degeneracy (cf. d orbitals, or t2g and eg), but rather the E representation associated with C3 symmetry of the triangles.

Hund's rule coupling. 
This involves the E orbitals and arises purely from the Hubbard U on the non-degenerate orbital on a single lattice site.

Spin-orbital coupling.
This is Spin Molecular Orbital Coupling, where the electron spin couples to the angular momentum associated with motion around the triangle, not the angular momentum of degenerate atomic orbitals.

Haldane phase.
The associated spin-1's arise from the triplet ground state of four electrons on a triangle.
A DMRG study shows that this is the ground state of a three leg-ladder Hubbard model at 2/3 filling.

Many interesting and important open questions remain about the general phase diagram of the Hubbard model on the kagomene lattice. For example, the nature of the Mott insulator, different types of topological order, the possibility of superconductivity.....

Hopefully, these studies will stimulate new experimental studies and synthesis of new chemical compounds in this fascinating class of materials.

Thursday, June 29, 2017

Was that email ethical?

I asked yesterday How would you respond to this email?

I read it carefully and did not reply.
The most striking thing was how generic it was. Although praising me and my work it never mentioned any specifics.
Sometimes when I get student inquiries I send them an email similar to that below.
Thanks for your interest.Please send me a copy of your CV and grade transcript.
I suggest you look at my blog under the label “hydrogen bonds” or "strongly correlated electrons" to get some idea of my current interests.
Also look at  “undergrads” and/or “Ph.D” to get some idea of my views and philosophy on supervision.
I suggest after looking at the blog you then write and send me two paragraphs:
one on why the science interests you and one on your perspective as to my philosophy.
After that, if you are still interested I suggest we then meet in person.
However, I did not send such an email for several reasons. I usually delete generic inquiries. If the student has not bothered to find out or articulate anything specific about me I doubt they are a very good researcher. I also want to work with people who want to work with me, not just anyone. Furthermore, tuesday was busy and I was not going to adjust my schedule for a student who was just showing up on a random day. 
So, I deleted the email.

I was fascinated that the next day I received a follow-up email.

Subject: Debrief Email: Follow-up from "Meeting: Prospective Doctoral Student"

Dear Professor McKenzie,

Yesterday, we, Associate Professor B... and Associate Professor M..., sent you an email inquiring about research opportunities as part of an experimental study on the effects of name identifiers on responsiveness to email communications. Our research is concerned with informal pathways to academic careers and involved random assignment of different sender names to test their effects on response rates from a large number of academics across Australia. Although the email was purportedly from a prospective research student, in reality this deceptive claim was a necessary element of the experimental design and the email was sent by us. We understand that this may cause concern. We are sending this email to reassure you that the data collected are anonymous, the study has the approval of the appropriate ethics committee, the deception was absolutely necessary for the integrity of the research, and only aggregate response patterns across groups, fields, and universities will be studied. 

Our study is titled “An Open Door? Experimental Measurement of Potential Bias in Informal Pathways to Academia.” All of this study’s data will be permanently anonymised, so there will be no identification of you or any individual with any response record. All names and email addresses will be permanently removed from the data and discarded. This study is only concerned with aggregate response rates. No individual response or lack thereof can indicate anything by itself, and your anonymised individual response will not be the subject of our analysis. 

Research involving humans in Australia is reviewed by an independent group of people called a Human Research Ethics Committee (HREC). The ethical aspects of this study have been approved by the HREC of the University of Sydney (protocol number 2015/757). As part of this process, we have agreed to carry out the study according to the National Statement on Ethical Conduct in Human Research (2007) (Updated May 2015). This statement has been developed to protect people who agree to take part in research studies. Because we are only measuring response rates to a single email, it was not possible to request consent prior to your participation. 

We greatly appreciate your participation in this study and will be happy to provide a copy of our report on the study results, once it is ready. We also understand that your response to our email took time and effort to write. We apologise for this. We believe the research we are doing is of considerable importance for improving understanding and informing policy. To receive our report, or if you have any other questions, comments, or concerns please contact  us ... [names and emails]

If you prefer, you may also or alternatively contact the Manager, Ethics Administration, University of Sydney. 

If you are concerned about the way this study is being conducted or you wish to make a complaint to someone independent from the study, please contact the university using the details outlined below. Please quote the study title and protocol number. 

Wow! 
I guess this email generated quite a firestorm because within 5 hours I received the following email.

Subject: Follow up research ethics

Dear Professor McKenzie,
Project Title: An Open Door? Experimental Measurement of Potential Bias in Informal Pathways to Academia

Project No: 2015/757

The University of Sydney has received a number of complaints in relation to this research project and its approval. The University takes these complaints seriously and the issues raised will be looked into by the HREC Executive committee. The project has currently been suspended.

All participants will be informed of the outcome of this review.

If you have further concerns about the way this study is being conducted or you wish to make a complaint to someone independent from the study, please contact the Manager of Ethics Administration using the details outlined below. Please quote the study title and protocol number. 


By the way, the name of my "student" was "Melindah Weelyrah". A Google search showed nothing. In contrast, one of my colleagues received an email from a name which he Googled and found a real web page at U. of Sydney for an apparently real person with relevant research physics interests. He did reply to the email.

Is this ethical? What do you think? Would you have filed a complaint?

Did the strong negative reaction from the "subjects" in the study stem from the "deception" or that they do not like having their time "wasted"?

This reminded me of the Brisbane bus driver racism study that caused a major controversy. The research results were overshadowed by the ethics questions and how the university treated the chief investigator.

Wednesday, June 28, 2017

How would you respond to this email?

On monday, I received the following email.

Subject: Meeting: Prospective Doctoral Student

Dear Professor McKenzie,

My name is M... W.... I have recently finished my honours degree and I am interested in undertaking doctoral study. The project I have in mind is closely related to your research. I became very familiar with your work while writing my thesis, and am eager to learn as much as I can about research opportunities with you. 

I was wondering if you might have 10 minutes when you would be willing to meet with me to briefly talk about your work and any possible opportunities for me to get involved in your research. I will be on campus today, and will also be available for the rest of the week. Any time would be fine with me. Meeting with you is among my highest priorities as I prepare to apply for doctoral studies.

Thank you in advance for your consideration.

Sincerely,
M.... W...

Tomorrow, I will reveal how I responded and the ensuing firestorm... It is a fascinating story.

But, first I am curious to hear how you would have responded.

Friday, June 23, 2017

Refereeing papers: recent experiences at the coal face

I am not a big fan of the peer review process. Too often it is a superficial ritual that adds little scientific value. Nevertheless, when it does work I think it can be very valuable. Here are some of my recent experiences that I thought were rather positive, and may be marginally interesting to readers.

I was sent a paper by JCP to review. Overall, I liked it but I thought it would benefit from some significant revisions. In a weird coincidence, I was visiting the same institution as some of the authors. I have been recently challenged about whether peer review really should be anonymous [see this discussion of SciPost] and so I took a risk. I signed my report and sent a copy to all the authors and told them I would be happy to meet to discuss the paper. We met and had a nice discussion. However, it was interesting that JCP told me that they had deleted my self-identification as it was against their policy.

I was sent a paper by PRL to review that I (and other referees) took a strong dislike to. The cover letter was also "Interesting". I wrote a concrete critical report. However, for the first time ever, I used the box for "Comments that will only be seen by the Editors". I said the authors had inappropriately used and cited my own work, that the paper was in the class "Not even wrong", and that if PRL published it, PRLs reputation in a certain community would suffer. Maybe I am a coward, but I am glad I was anonymous.

I got a paper I liked to review from JCP. However, the authors did not engage with a whole physics literature that was relevant to the paper and they needed to use it to sharpen their results. I think the final paper will be much better and more interesting.

A recent paper with my postdoc got two critical but constructive reports from PRB. This required some new calculations and comparisons but was much better as a result. Today we heard it was accepted.

I now decline all referee requests from luxury journals. I have limited time and would prefer to invest in journals that I think are making a positive contribution to science.

Have you had any recent positive experiences as a referee or received a helpful report?

Monday, June 19, 2017

The scientific relevance of your hobby

On the one hand to make progress in science you need to focus, work hard, and build your expertise. This leads some to think that it best that they not pursue outside interests and hobbies such as art, music, craft, puzzles, games, ...
However, scientific discoveries, particularly big ones, often involve creativity, serendipity, or thinking outside the box.

I noticed two examples of this recently.
The first was how fascination with a cheap child's toy led to the key idea behind the development of extremely cheap centrifuge [paperfuge] for health diagnostics in the Majority World.



The second example was a New York Times article about a recent paper that argues that key to Pasteur's discovery of molecular chirality was his interest in art.

Another example, is Harry Kroto who shared The Nobel Prize in Chemistry for the discovery of buckyballs. He credited playing with Meccano as a child as very important in his scientific development.

Can you think of other examples?

Friday, June 16, 2017

Why do some people think they can get something for nothing?

This is a small rant. I want to stress that it is not because of anything directly involving me. Rather it comes from things that come across my desk and frustrations that friends and colleagues vent to me.

Here is a sample situation.
Professor A in Department B at University C wants to apply to funding agency D for a joint multi-million dollar research grant with Professor E in Department F at University G. There is also an industrial partner, company H. Obviously, if the application is successful then A to H will all benefit. But now comes the rub. All parties need to commit to contributing something: whether it is time, lab space, matching funds, intellectual property rights, reduced teaching or admin. responsibilities, hiring new people, giving someone a permanent job, equipment, infrastructure, ..... and they need to divide up the grant if they get it.

My frustration and concern are that I encounter cases where one or more of the parties are completely unreasonable about how little they should contribute, if at all. They seem to want something for nothing. Furthermore, they will persist in this even if it means the application won't proceed or has virtually no chance of success. They fail to believe that there will be other applicants who will have strong support and contributions from all the parties involved.

I know that resources are scarce, budgets are tight, and people want to drive a hard bargain. That is not what I am talking about. The real "Art of the Deal" is not the Trump version, but compromising to a win-win situation, not sabotaging the deal because of fantasy and blind selfishness.

Do you encounter situations like this?

Tuesday, June 13, 2017

How might we teach students to actually think?

Four important goals to me are to teach students:
1. To think.
2. To think like a physicist.
3. To think like a condensed matter physicist.
4. The specific technical content of the course.

The last one is arguably easier than the others.
I also think it is the least important. Others will disagree.
We don't reflect enough on how we might achieve the other goals.
The biggest challenge of improving education in the Majority World is not lack of material resources but changing the culture of rote learning and teaching critical thinking.
[This is highlighted in a NYTimes piece about China and a very funny video about India ITs].

Last week the UQ School of Maths and Physics Teaching Seminar was given by Peter Ellerton who works for the UQ Critical Thinking project.

The slides from a similar talk are here.
In the talk he mostly walked us through the three graphics shown here.
[If you click on the image you can see a high resolution .pdf]

The main value of all this is it puts names, categories, and questions on what I want to do. I found the third graphic the most helpful because it has some very specific questions we can ask students to get them to reflect more on what they are learning and in the process learn to think more critically.

Thursday, June 8, 2017

A lucid lecture on the last 50 years of superconductivity

At the weekly condensed matter theory cake meeting today we watched a video of a KITP blackboard talk given by Piers Coleman in 2015.
Superconducting Surprises: five decades of discovery, in both temperature and time!

It is a very nice exposition of the history and some of the key physics.

A couple of minor comments.

Organic superconductors were discovered in 1980 not 1973.

Piers claims that the difference between the thermodynamic entropy of the superconducting and metallic states (determined from integrating the temperature dependent specific heat) is related to the quantum entanglement entropy of the superconducting ground state.
The relationship between entanglement entropy (defined on a pure quantum state (at zero temperature) which is divided in two) and thermal entropies (defined for a bulk system in a mixed state at finite temperature) is an incredibly subtle and complex issue that I don't think is resolved. See for example the discussion in this paper.

Monday, June 5, 2017

The challenge of applied research

Last friday we were fortunate to have David Sholl give a physics colloquium at UQ,
``What Does Quantum Mechanics Have To Do With The Chemical Industry? Reflections On A Journey From Pure To Applied Research.''
Here are the slides.

David has a background in theoretical physics and has been particularly successful at using atomistic simulations to study problems that chemical engineers care about. He is co-author of a book, Density Functional Theory: A Practical Introduction
His three main points in the talk were
  • Applied research is worth doing and is intellectually satisfying
  • Applied research relies on fundamental insights 
  • How to waste time and money doing applied research
The piece of science I found most interesting was the figure below which shows how the calculated self-diffusion constant D of small hydrocarbons in a zeolitic imidazolate framework varies with the size of the hydrocarbon molecule.
Note how D varies over 14 orders of magnitude.

Some of the key physics is that this large variation arises because the diffusion constant is essentially determined by the activation energy associated with the transfer of a molecule through the molecular hole between adjacent pores. When the molecular size is comparable to the hole size, D rapidly diminishes because of steric effects.
It would be nice to have "simple" theory of the correlation.

The figure is taken from the paper
Temperature and Loading-Dependent Diffusion of Light Hydrocarbons in ZIF-8 as Predicted Through Fully Flexible Molecular Simulations 
Ross J. Verploegh, Sankar Nair, and David S. Sholl

Friday, June 2, 2017

The educational value of undergraduate research projects

This past semester I have been supervising two undergraduate research projects. One student is doing a one semester course (1/4 of the students load) for a third year student. The second student has a year long project for a fourth year student (1/2 of their load). I am very happy with how both have gone in terms of their educational value. The amount of research results is of secondary importance to me. Previously, I posted about possible ingredients for a good undergrad project. Both students are working on a simple model for hydrogen bonds. I recommend this because it has an "easy" learning curve and so they can start "doing science" quick. It also has a nice mix of theory and experiment, chemistry and physics.

Things that struck me as particularly valuable include the following very basic things. Some of which relate to basic but important skills.

Seeing calculations to completion. 
In an undergrad problem set or exam the student has limited time and gets partial marks for incomplete or wrong answers. In research you have to keep working on the problem until you have an answer and have checked it enough that you are confident it is the correct answer.

Personal attention.
Each week they get to meet one-to-one with a faculty member and get advice and feedback.

Units! 
Learning that they really do matter and you have to get them right. This converting between different unit systems.

Writing and debugging code.
Even a short Matlab or Mathematica code.

Reading papers not textbooks.
Gifted students can find textbooks quite manageable and understandable. Papers are in a different league.

Experiencing what research is often like.
Hard. Confusing. Boring. Tedious... But, progress and understanding can be quite satisfying.

Communication skills.
Giving a talk and writing reports, and getting feedback on them.

Job skills.
Time management. Showing up for meetings on time. Writing meeting summaries. Coming up with action plans. Listening to constructive criticism. Working with others.

Tuesday, May 30, 2017

Quantity swamps quality

Every now and then I have to review a lot of CVs. What is increasingly striking is the sheer quantity of "line items": papers, grants, citations, talks, seminars, Ph.Ds supervised, public outreach activities, referee activities, committee service, conference organisation, .....
Sometimes teaching, particularly of undergraduates, is almost an afterthought.

One concern is the difficulty of evaluating the quality of this hyperactivity.
This is why metrics are so seductive, particularly to the non-expert.
But even if you want to give some weight to numbers of papers, journal "quality", total research funding, ... I think they are quite hard to interpret.
In some research areas,  papers often have ten authors, and so it is very difficult to know an individual's contribution, even if they are first or last author. I increasingly encounter statements such as "Since I became a faculty member ten years ago I have attracted $7M of external funding". This sounds very impressive. However, once you look at the details you find a mix of grants with long lists of CIs, such as infrastructure grants. Again it is not clear whether the individual was really that central to many of the grants.

Another concern, is I am skeptical that these "highly productive" people have the time, energy, and focus needed to think deeply, work on challenging and ambitious projects, and produce much that is scientifically significant. Quantity crowds out quality.

Finally, it worries me that for many of these people the "system" seems to be "working" for them, i.e. they are getting jobs, promoted, funded, ...

Now I do concede that in some cases I do not have the expertise to fully appreciate the significance or value of what people are doing. However, I fear that is the exception, not the rule.

If my concerns are legitimate, what is the way forward?
If assessing, it is very important to have people involved who have the necessary expertise to critically and fairly evaluate the quality of people's individual scientific contributions. This means asking for and reading letters of reference, and actually reading some of their papers. Neither is infallible but it is a lot better than bean counting.

It is possible for individual fields to preserve a culture of quality taking precedence over quality. For example, in pure mathematics and economics, you will find that "publication rates" can be almost an order of magnitude lower than in physics and chemistry.

On the practical side, you might also consider editing and shortening your own CV so the signal to noise ratio is higher.

Finally, I hope you will personally resist uncritically following this rush to mediocrity.

Is my concern legitimate? If so, what are the ways forward?

Tuesday, May 23, 2017

How should undergraduate quantum theory be taught?

Some of my colleagues and I have started an interesting discussion about how to teach quantum theory to undergraduates. We have courses in the second, third, and fourth years. The three courses have independently evolved, depending on who teaches each. Some material gets repeated and other "important" topics get left out. One concern is that students seem to not "learn" what is in the curriculum for the previous year. The goal is to have a cohesive curriculum. This might be facilitated by using the same text for both the second and third-year courses.
This has stimulated me to raise some questions and give my tentative answers. I hope the post will stimulate lots of comments.

The problem that students don’t seem to learn what they should have in pre-requisite courses is true not just for quantum. I encounter second-year students who can’t do calculus and fourth-year (honours) students who can’t sketch a graph of a function or put numbers in a formula and get the correct answer with meaningful units. As I have argued before, basic skills are more important than detailed technical knowledge of specific subjects. Such skills include relating theory to experiment and making order of magnitude estimates.

Yet, given the following should we be surprised?
At UQ typical lecture attendance probably runs at 30-50 per cent for most courses. About five per cent watch the video. [University policy is that all lectures are automatically recorded]. The rest are going to watch it next week… Only about 25 per cent of the total enrolment in my second-year class are engaged enough to be using clickers in lectures. Exams are arguably relatively easy, similar to previous years, usually involve choosing questions/topics, and a mark of only 40-50 per cent is required to pass the course.
I do not think curriculum reform is going to solve this problem.

Having the same textbook for 2nd and 3rd year does have advantages. This is what we do for PHYS2020 Thermodynamics and PHYS3030 Statistical Mechanics. But, some second years do struggle with it... which is not necessarily a bad thing. The book is Introduction to Thermal Physics, by Schroeder.

Another question is what approach do you take for quantum: Schrodinger or Heisenberg, i.e. wave or matrix mechanics? The mathematics of the former is differential equations, that of the latter is linear algebra. Obviously, at some point you teach both, but what do you start with. It is interesting that the Feynman lectures really start with and develop the matrix approach, beating the two level system to death...
At what point do you solve the harmonic oscillator with creation and annihilation operators?
When do you introduce Dirac notation?

I would be hesitant about using Dirac notation throughout the second year course. I think this is too abstract for many of our current students. They also need to learn and master basic ideas/techniques about wave mechanics: particle in a box, hydrogen atom, atomic orbitals, … and connecting theory to experiment... and orders of magnitude estimates for quantum phenomena.

What might be a good text to use?

Twenty years ago (wow!) I taught second (?) year quantum at UNSW. The text I used is by Sara McMurry. It is very well written. I would still recommend it as it has a good mix of experiment and theory, old and new topics, wave and matrix mechanics….
It also had some nice computer simulations. But it is out of print, which really surprises and disappoints me.

Related to this there is a discussion on a Caltech blog about what topics should be in undergraduate courses on modern physics. Currently, most "modern" physics courses actually cover few discoveries beyond about 1930! Thus, what topics should be added? To do this one has to cut out some topics. People may find the discussion interesting (or frustrating…). I disagree with most of the discussion, even find it a little bizarre. Many of the comments seem to be from people pushing their own current research topic. For example, I know it is Caltech, but including density matrix renormalisation group (DMRG), does seem a little advanced and specialised...
There is no discussion of one of the great triumphs of "modern" physics, biophysics! I actually think every undergraduate should take a course in it.

What do you cut out?
I actually think the more the better, if the result is covering a few topics in a greater depth that develops skills, creates a greater understanding of foundations, that all leads to a greater love of the subject and a desire and ability to learn more.
In teaching fourth year condensed matter [roughly Ashcroft and Mermin] it is always a struggle to cut stuff out. Sometimes we don't even talk about semiconductor devices. This year I cut out transport theory and the Boltzmann equation so we could have more time for superconductivity. This is all debatable... But I hope that the students learned enough so that they if they need to they have the background they need to easily learn these topics.

A key issue that will divide people concerns the ultimate goal of a physics undergraduate education. Here are three extreme views.

A. It should prepare people to do a PhD with the instructor.
Thus all the background knowledge needed should be covered, including the relevant specialised and advanced topics.

B. It should prepare people to do a physics PhD (usually in theory) at one of the best institutions in the world.
Thus, everyone should have a curriculum like Caltech.

C. It should give a general education that students will enjoy and will develop skills and knowledge that may be helpful when they become high school teachers or software engineers.

What about Academic Freedom?
This means different things to different people. In some ways I think that the teacher should have a lot of freedom to add and subtract topics, to pitch the course at the level they want, and to choose the text. I don't think department chairs or colleagues should be telling them what they "have" to do. Obviously, teachers need to listen to others and take their views into account, particularly if they are more experienced. But people should be given the freedom to make mistakes. There are risks. But I think they are worth them in order to maintain faculty morale, foster creativity, maintaining standards, and honouring the important tradition of academic freedom. Furthermore, it is very important that faculty are not told by administrators, parents, or politicians what they should or should not be doing. Here, we should bear a thought for our colleagues in the humanities and social sciences, particularly in the USA, who are under increasing pressure to act in certain ways.

I welcome comments on any of the above.
My colleagues would particularly like to hear any text recommendations. Books by Griffiths, Shankar, Sakurai, and Townsend have been mentioned as possibilities.