Dr Ruth Williams


  • 1974-1976: Research Fellow, Girton College, Cambridge
  • 1976-present: Official Fellow, College Lecturer and Director of Studies in Mathematics, Girton College
  • 1991-1994: Temporary Lecturer, DAMTP, Cambridge
  • 1994-2002: Assistant Director of Research, DAMTP
  • 2002-present: Reader in Mathematical Physics, DAMTP


Discrete gravity, both classical and quantum, mainly based on Regge calculus; spin foam models. The role of holonomy in quantum gravity. The variation of Newton's constant.

Selected Publications

  • Discrete structures in physics, J. Math. Phys. 41 (2000) 3964-3984 (with T. Regge).
  • 6j-symbols and discrete quantum gravity, Nucl. Phys. B (Proc. Suppl.) 88 (2000) 124-131.
  • Flat and curved space-times: Second edition, Oxford University Press (2000) (with G. F. R. Ellis).
  • Gluing 4-simplices: a derivation of the Barrett-Crane spin foam model for Euclidean quantum gravity, Phys. Rev. D63 (2001) 024022 (with D. Oriti).
  • Constraints on area variables in Regge calculus, Class. Quantum Grav. 18 (2001) L43-46 (with J. M\"akel\"a).
  • Non-perturbative gravity and the spin of the lattice graviton, Phys. Rev. D70 (2004) 124007 (with H. W. Hamber).
  • Area Regge calculus and discontinuous metrics, Class. Quantum Grav. 21 (2004) 4865-4880 (with C. J. Wainwright).
  • Nonlocal effective gravitational field equations and the running of Newton's constant G, Phys. Rev. D72 (2005) 04426 (with H. W. Hamber).
  • Nonlocal effective field equations for quantum cosmology, Mod. Phys. Lett. A 21 (2006) 735 (with H. W. Hamber).
  • Quantum gravity in large dimensions, Phys. Rev. D73 (2006) 04403 (with H. W. Hamber).
  • Discrete quantum gravity, Journal of Physics: Conference Series 33 (2006) 38-48.
  • Bertha Swirles Jeffreys, in Out of the Shadows: Contributions of Twentieth-Century Women to Physics, edited by Nina Byers and Gary Williams (CUP, 2006).
  • Constraints on the gravitational scaling dimension from the non-local effective field equations, Phys. Lett. B643 (2006) 228 (with H. W. Hamber).
  • Renormalization group running of Newton's G: the static isotropic case, Phys. Rev. D75 (2007) 084014 (with H. W. Hamber).
  • Gravitational Wilson loop and large scale curvature, Phys. Rev. D76 (2007) 84008 (with H. W.Hamber).