Up: Theory group
I work with Judith McGovern at the intersection between particle and nuclear physics. In particular we are interested are in the role played by the symmetries of quantum chromodynamics (QCD) in the structure and interactions of nucleons and mesons. The most important of these symmetries of the strong interaction is a chiral symmetry which is respected by up and down quarks (the ones we are made of) because they have very small masses in QCD. The strong attraction between quarks and antiquarks means that "empty" space is filled with a Bose-Einstein condensate of quark-antiquark pairs, which acts like a Higgs field and hides the chiral symmetry. Our work takes advantage of the way pions (the lightest mesons) "remember" this symmetry in their interactions. It makes use of a range of theoretical techniques including effective field theory and the renormalisation group.
We are also interested in transitions from ordinary nuclear matter to new phases such as a quark-gluon plasma or a colour superconductor. The plasma is the phase of matter which existed shortly after the Big Bang, and which may be recreated by colliding heavy nuclei together at ultrarelativistic energies. Colour-superconducting quark matter may exist at very high densities in the centre of neutron (or quark) stars. In our studies of strongly interacting matter we collaborate with Niels Walet.
For more on these ideas, see the talk I gave at a recent UK Workshop on QCD in Nuclear and Hadronic Physics (pdf file, 165 kB) and also the chapters on QCD (pdf file, 320 kB) and Phases of Nuclear Matter in the NuPECC Long Range Plan 2004 (pdf file of the whole report, 9.4 MB). An informal account of chiral symmetry and related ideas can be found in:
Some recent (and not-so-recent) papers on these topics are listed here.
My preprints since 1993 are posted on hep-ph and nucl-th at the Cornell e-print archive (also available via the Southampton mirror). A more complete list of my publications can be found on the SLAC SPIRES database (also available via the Durham mirror).
Manchester is a node of the network N5: Structure and Dynamics of Hadrons, which is part of the European Integrated Infrastructure Initiative on Hadron Physics (I3HP). I have served on the board of directors of the European Centre for Theoretical Studies in Nuclear Physics and Related Areas (better known as the ECT*). This hosts workshops on topics in nuclear and hadron physics, and also on subjects ranging from Bose-Einstein condensation to string theory.
Conferences and workshops organised by the group:
23rd September 2010
Up: Theory group