Condensed concepts

I have now finished my first draft of chapter 4, of Condensed Matter Physics: A Very Short Introduction. The main purpose of the chapter is to introduce the idea and significance of the order parameter.  I welcome comments and suggestions. However, bear in mind that my target audience is not the typical reader of this blog, but rather your non-physicist friends and family. I think it still needs a lot of work. I may split this chapter into two. The goal is for it to be interesting, accessible, and bring out the excitement and importance of condensed matter physics.

When studying quantum many-body theory, sometimes one gets lost in all the indices, functional integrals, Feynman diagrams, ... Then one can lose sight of the fact that some techniques are really just the same as in simple mathematics. Examples include  the method of steepest descent  and  cumulant expansions. In basic algebra, a simple exercise is to complete the square  in a quadratic equation, i.e. to make use of the following identity. Suppose one has the following Hamiltonian. If describes a field q that couples linearly to a different field s, with a coupling constant s.  Now if we complete the square and do a displacement of the field q we are left with the new Hamiltonian. This now describes a free field q (i.e. non-interacting) and there is an attractive self-interaction of the field s with coupling constant a^2. A related example is the  Hubbard-Stratonovich_transformation . This allows one to introduce a new field that couples to the original field and then `

This friday I am giving a 5-10 minute talk on work-life balance to a group of postdocs and young faculty from the School of Mathematics and Physics at UQ. I was asked because I previously gave a School Colloqium about mental health. There will be three speakers and time for discussion. Humorous aside: When I was asked in person to give this talk, I thought I heard that the invitation was from the ``Early career comedy". So I thought, ``I guess they are using comedy (such as skits) to cope with the stress of their work situation. But, I am surprised that they asked me because I am not really that funny." After a few minutes of discussion, I realised that I had misheard. The invitation was from the ``committee" not for a ``comedy"! What do you think I should say or not say? Here are a few preliminary thoughts. Start with empathy. I remember this life stage as stressful and I did not always manage it well. Indeed, several times I have had mental health prob

One of the most basic skills needed to succeed, or even survive, in professional life is to be able to write well. This is true whether you work in science, industry, business, or an NGO. Of course, there are exceptions where an individual is incredibly gifted at the technical side of a job and can't even write a coherent paragraph. But, sorry, that individual is probably not you! Furthermore, even they need a collaborator or manager who is good at writing. Most young scientists struggle to write a paper or a grant application, particularly when English is not their first language. Here are a few suggestions on how to improve your writing skills over time. First, accept that writing is hard work. Even John Grisham says that! Accept that developing your writing skills is a project of a lifetime. This means starting early. If you are an undergrad, take some humanities courses that require writing essays. Take writing lab reports seriously. If you have to write a thesis, s