Group Members 

Permanent Staff 

     Dr. Adi Armoni

     Prof. David Dunbar

     Prof. Tim Hollowood

     Dr. S. Prem Kumar

     Dr Dario Martelli

     Dr. Asad Naqvi

     Dr. Carlos Nunez

     Dr. Warren Perkins

     Dr. Maurizio Piai

     Prof. Graham Shore  (Head of Theory Group)

 Postdoctoral Research Officers: 

     Dr. Suvankar Dutta

     Dr. James Ettle

     Dr. Joyce Myers

The research of the group focuses on String Theory, non-perturbative aspects of Quantum Field Theories, LHC phenomenology and Cosmology.  

Recent research highlights: 

* construction of the first generalisation of the AdS/CFT correspondence to a theory with minimal suspersymmetry, initiating the search for gravity duals of phenomeologically realistic gauge theories (CN). 

* extensions of AdS/CFT to include fundamental matter fields, allowing non-perturbative investigation of chiral symmetry breaking, instantons, Seiberg duality, Wilosn loops and running couplings (CN). 

* string-inspired methods to develop multi-instanton calculations in SUSY gauge theories, enabling an evaluation of the gluino condensate in N=1 theories and establishing S-duality in N=2 Seiberg-Witten theories (TH). 

* evaluation of exact superpotentials in a large class of deformed N=4 theories exhibiting N=1 supersymmetry, demonstarting how the vacuum structure can be determined by finding equilibrium points of an analogue finite-dimensional dynamical system (TH, SPK) 

* demonstration of one-loop renormalisability in non-commutative gauge theories, together with an interpretation of UV-IR mixing in terms of closed string tachyons (AA). 

* investigation of topological string theory on manifolds with G_2 holonomy (AN).

* quantisation of strings on spacetimes with time-dependent singularities, resolving conceptual issues concerning unitarity, energy non-conservation and the occurence of closed timelike curves (AN).

* use of the gauge/gravity duality to probe new strong-coupling phases inQCD-like theories at non-zero temperature and baryon density, and determine their relation with new phases of quantum black holes in the dual string theory (TH,SPK,AN). 

* analysis of observational tests of quantum gravitational optics, Lorentz and CPT violation in astrophysical polarimetry and precision antihydrogen spectroscopy (GS).

* determination of the QED dispersion relation for light propagating in a curved spacetime, reconciling superluminal low-frequency propagation with a causally consistent UV limit and elucidating the relation of the UV completion of a QFT with its low-energy realisation (TH,GS). 

* the discovery that scattering ampitudes in N=8 supergravity have unexpectedly well-behaved UV properties, raising the possibility that this may indeed be a UV-finite quantum theory of gravity (DD,WP) 

* elucidation of the twistor-space structure of one-loop amplitudes in Super Yang-Mills theory, and application to perturbative QCD calculations of multi-jet processes at LHC (DD,WP). 

* development of "planar equivalence" of supersymmetric and non-supersymmetric gauge theories in a large-N_c limit; in partcular an orientifold theory interpolating between N=1 SYM and QCD was used used to derive the chiral condensate in QCD from the exact result for the gluino condensate in SYM (AA). 

* extension of the Witten-Veneziano formula for the eta^prime mass beyond the large-N_c approximation and a quantitative analysis ofpseudoscalar meson decays (GS).

* experimental confirmation by the COMPASS and HERMES collaborations of a numerical prediction for the proton spin sum rule in terms of the gluon topological susceptibility, and a proposal to test the analogous polarised photon sum rule at high-luminosity B-factories (GS). 

* embedding of walking technicolor theories of electroweak symmetry breaking in UV-complete extended technicolor models exhibiting the main properties of  standard-model fermions, including mass hierarchies, intergenerational mixingand suppressed neutrino masses (MP).