New directions for intergroup meetings Tom Lancaster

We’re hoping to make talks more accessible, wide-ranging and interesting Less emphasis on technical descriptions of your most recent results Talks can be introductory, speculative, provocative and outside the immediate field of materials physics. What are we trying to do?

Particular suggestions Journal club: a discussion of a scientific paper Topical physics: ideas from across physics needed to understand something in your field Personal hobby-horse: be it cookery, rocketry, electronics, music… Discussion and debates

Please submit talk titles in advance If something looks too inaccessible, we’ll ask you to think again Please don’t be offended!

Suggestions box If you have something you’d like someone to talk about send an to chairs or to

Journal club talks Pick a paper. Nature, Science, PRL, historically important

Paper by L D Landau, JEPT 30, 1058 (1956) Describes a new, phenomenological model of metals

Context and background What problem is being discussed? Why is this important? Who is writing the paper?

The fermi gas treats electrons as non-interacting It describes metals very well, but it shouldn’t Electrons interact very strongly – is there a better way? Lev Landau invented much of condensed matter physics, his answer to this question caused a revolution.

What’s in the paper What are the important results described? What do the authors conclude?

Fermi liquid made of quasiparticles – one for each electron Excitations are unstable, but the ones near the Fermi energy live the longest Landau’s expansion of the energy allows him to describe the system with only a few parameters

What do you think of the paper? Are the results convincing? Can someone else do better Keep literary criticism to a minimum!

What do you think of the paper? Are the results convincing? Can someone else do better Keep literary criticism to a minimum! Early Chinese chemists could not have imagined two thousand years ago that BaCuSi 2 O 6 was not only an attractive purple pigment but also a potential solid state device for exploring the quantum effects of a BEC at liquid 4 He temperatures in magnetic fields. (PRL 93, (2004))

Landau’s paper is very sketchy – it’s hard to know what the big idea is It turned out to be incredibly important – the standard model of CMP It’s a work of genius!

Future work What next for this field? How does this paper fit into the grand scheme

Guide to talks Keep them short Make it simple Keep slides uncluttered Everyone likes history, psychology, sociology… Avoid length conclusions! See N D Mermin, Physics Today, November 1992, page 9.