M.Sc. in Quantum Fields and Symmetry
Quantum Fields and Symmetry
The past thirty years have seen dramatic advances in our quest to
understand the fundamental laws of physics, that is, those governing
the most elementary constituents of matter. The Standard Model
of particle physics has as its prototype the theory known as
Quantum Electrodynamics (QED), which describes interactions
between electrically-charged particles such as electrons in terms of
exchange of an intermediate particle -- the photon, a quantum of
light. QED displays two important ingredients of modern theories:
firstly it generalises single-particle quantum mechanics to the
electromagnetic and particle fields defined at each point of space,
and is thus a Quantum Field Theory; secondly it has a Gauge
Symmetry, which ensures the photon remains massless and hence the
electromagnetic interaction operates over macroscopic
distances. Symmetry is perhaps the most important guiding principle:
it helps to build models and tightly restricts the number which make
physical sense.
The gauge principle is used to construct the Electroweak Theory
which decribes both electromagnetic and weak nuclear forces in terms
of a Unified Theory. The symmetry of this theory is larger,
resulting in more force-carrying quanta; W and Z bosons in addition to
the photon. The W and Z are massive particles, respectively 80 and 90
times the proton rest mass, which accounts for the short range of the
weak interaction. Their existence was confirmed in collider
experiments at CERN in 1983. One mystery which remains is the precise
mechanism which causes the symmetry between photons, Ws and Zs to
break down; indeed, the same symmetry if unbroken would prohibit every
known particle from having mass. The best explanation to date is in
terms of a new fundamental field, the Higgs. It is hoped that
the next generation of collider experiments using the LHC machine at
CERN will shed more light.
Another gauge theory, Quantum Chromodynamics, has been proposed
to model the strong interactions which confine quarks within nucleons,
and bind nucleons in turn within nuclei. Because the interaction is
strong, the approximation used in QED, namely that interactions are
dominated by single particle exchange, loses its validity, and new
approaches must be tried. One of the most popular involves formulating
the field theory on a discrete spacetime lattice, and then simulating
quantum fluctuations using powerful computers. The goal of such
studies is a first principles calculation of the proton mass.
There are hopes that eventually both strong and electroweak interactions
will be understood in a Grand Unified Theory, whose symmetry
would only be manifest at extremely high energies (about 10^15 GeV) or
temperatures such as those present in the early universe. For this
reason the links between particle physics and Cosmology are
becoming stronger. Another aim is for the fourth fundamental force of
nature, gravity, to be unified with the other forces in some
all-embracing Theory of Everything. So far attempts to reconcile
General Relativity with quantum theory have proved inconclusive;
this remains the outstanding challenge of theoretical physics. The most
promising line of research involves extended one-dimensional entities --
Superstrings. Although a fundamental dynamical principle
governing their behaviour remains elusive, superstrings have inspired
much recent progress in low-dimensional field theories which have a
large set of Conformal symmetries -- these in turn have proved
applicable in understanding and classifying phase transitions in
condensed matter systems.
M.Sc. Course
Quantum Fields and Symmetry is an introduction
to modern theoretical physics, especially the quantum field theories
and symmetries which are at the heart of our understanding of
fundamental physics.The course is intended to take students
with an undergraduate degree in physics or mathematics to the
level at which they can begin active research.
Students make a selection from the following courses:
Group A:
Group B:
Group C
All Group A and B and at least 3 Group C courses will be offered
each year. Group B courses are compulsory. One course may alternatively
be selected from the M.Sc. in Mathematics. Assessment is by written
examination.
Students also produce a Dissertation on a research topic within the
fields of interest of the theoretical physics group.
In line with the situation at other UK universities, there is
at present no financial support available from the UK research
councils for students attending this M.Sc. course, but the
situation is under review. Overseas students are encouraged to seek
financial support from sources in their home countries or from
the British Council.
For further information and application forms, contact:
Theoretical Physics Group Secretariat
Department of Physics
University of Wales, Swansea
Singleton Park
Swansea SA2 8PP
United Kingdom
Academic Staff
The majority of the M.Sc. lecture courses are given by the
members of the Theoretical Physics Group listed below with their
research interests:
- Professor I.G. Halliday
- Numerical quantum field theory; conformal symmetry;
Virasoro representations; negative dimensional integration;
anomalies.
- Professor D.I. Olive, FRS
- Gauge and string theories of the fundamental forces;
conformal field theories and their breaking to integrable
field theories; the origin of mass.
- Dr. G.M. Shore
- Renormalisation group, anomalies and geometry in quantum
field theory; conformal symmetry; quantum field theory, black holes
and cosmology; U(1) anomaly and QCD phenomenology; supersymmetry;
composite models and dynamical symmetry breaking.
- Dr. N. Dorey
- Semi-classical problems in quantum field theory; soliton quantisation
and the Skyrme model; instantons, baryon number violation; gauge
theories in 2+1 dimensions, fractional statistics, high $T_C$
superconductivity; topological field theories; dynamical symmetry
breaking.
- D.C. Dunbar
- String theory, both as a fundamental theory of quantum gravity
and as a calculational technique in QCD; conformal field theory.
- Dr. S.J. Hands
- Lattice gauge theories; lattice fermion formulations; strongly
coupled field theory; electroweak baryogenesis; QED; QCD vacuum;
monopoles.
- Dr. T. Hollowood
- Non-perturbative approaches to 2-dimensional quantum field
theories, especially asymptotic freedom
and other renormalisation group phenomena; massive integrable
quantum field theories, renormalisation group trajectories
and exact scattering matrices; integrability of 2-dimensional quantum
gravity and applications to string theory.
In addition, the group comprises Temporary Lecturers, Advanced Research
Fellows, Postdoctoral Research Assistants and Visiting Academics.
Including graduate students, the total group numbers around 30
researchers.
There are complementary research groups in the Department of Mathematics,
with interests in operator algebras, statistical mechanics and
integrable systems, path integrals and solitons. Some of the M.Sc.
lecture courses are given by members of these groups.
PhD and MPhil Research
Students who wish to pursue research after completing the M.Sc. course
may be admitted to a research degree, either the MPhil (one year) or
PhD (normally two or three years). Opportunities exist within the
Mathematics and Physics departments at Swansea for research in a wide
variety of topics in mathematical and theoretical physics. The M.Sc. degree
is also a valuable qualification for students wishing to move on to
a higher degree at another university.
MPhil and PhD students are individually supervised by a member of staff.
At present there are around 15 students registered for MPhil/PhD degrees
in the Theoretical Physics group. Facilities are good, with attractive
offices, a well-stocked group library and excellent computing resources
including two DEC alpha workstations.
Financial support for approximately three studentships each year is
provided by the Particle Physics and Astronomy Research Council and the
University of Wales. Students from European Community countries may
be eligible for EC studentships. Overseas students are encouraged
to seek financial support within their home countries.
A feature of postgraduate study at Swansea is the Graduate School,
recently set up to improve the status and professionalism of
graduate education. A catalogue of all the courses onthe campus
will be available to encourage students to extend their knowledge.
General courses in intellectual property rights, innovation,
library and computer skills, etc. will be provided. A system of
graduate representation is in place. The School will also act as
a focus for the social life of graduate students.
University of Wales, Swansea
The University of Wales, of which Swansea is one of six constituent
but largely self-governing institutions, is the second largest
university in the UK and has recently celebrated its centenary.
The University College of Swansea was itself founded
in 1920 and is now home to some 6,500 students. It is therefore
large enough to support a wide range of academic and social activity,
with major Faculties of Arts, Economic and Social Studies, Engineering
and Science, while at the same time being small enough to
ensure a strong sense of community. There is a distinguished
tradition of research in mathematics and physics reaching back
to the early years of the College's existence.
The campus is attractively situated on the sea-front in the grounds
of Singleton Park overlooking Swansea Bay, midway between
the city centre and the picturesque fishing village of Mumbles.
The Theoretical Physics group was created in 1992 following the
appointment of Professors I.G. Halliday and D.I. Olive to Chairs in
the Departments of Physics and Mathematics respectively. The group
has expanded rapidly and is already one of the largest research groups in
fundamental theoretical physics in the U.K., with interests in quantum
field theory, elementary particle physics, cosmology, computational
field theory and the mathematical description of the symmetries of the
fundamental interactions of nature.
Swansea and the Gower
Attractively situated on the South Wales coast, Swansea has much to offer
prospective students. The unspoilt coastline of the Gower peninsula
boasts some of the best beaches in Britain, with many National Trust
reserves. The area is ideal for all types of water sport, including
sailing, surfing and diving, and is a golfer's paradise, while the
nearby Welsh mountains offer many opportunities for hiking and climbing.
For the adventurous, the Gower cliffs are a centre for hang-gliding.
The University has an excellent sports centre, and top quality rugby
and cricket is played at the St Helens ground adjacent to the seafront
campus. Cultural activities are well catered for, with the modern
Taliesin Theatre and Arts Centre on campus and the Brangwyn Hall
and Grand Theatre providing drama, film, music and art.
With its cheap and plentiful accommodation and a lively student scene
in the pubs and clubs, Swansea enjoys a reputation as a popular
and friendly university city.
