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Correlation Functions of the Energy Momentum Tensor on Spaces of Constant Curvature
Abstract An analysis of one- and two-point functions of the energy–momentum tensor on homogeneous spaces of constant curvature is undertaken. The possibility of proving a c -theorem in this frameworkExpand
Dimensional regularization of massless quantum electrodynamics in spherical spacetime
Abstract The quantization and renormalization of massless electrodynamics in a spacetime of constant curvature are discused. A formalism is presented which is valid in an arbitrary number ofExpand
The c and a-Theorems and the Local Renormalisation Group
The Zamolodchikov c-theorem has led to important new insights in our understanding of the renormalisation group and the geometry of the space of QFTs. Here, we review the parallel developments of theExpand
“Faster than light” photons and charged black holes
Abstract Photons propagating in curved spacetime may, depending on their direction and polarisation, have velocities exceeding the “speed of light” c . This phenomenon arises through vacuumExpand
Superluminality and UV completion
Abstract The idea that the existence of a consistent UV completion satisfying the fundamental axioms of local quantum field theory or string theory may impose positivity constraints on the couplingsExpand
The U (1) Goldberger-Treiman relation and the two components of the proton “spin”
Abstract We present a simple and rigorous derivation of a recently proposed generalisation of the Goldberger-Treiman relation, and discuss its renormalisation group properties. We then show how toExpand
Quantum gravitational optics
In quantum theory, the curved spacetime of Einstein's general theory of relativity acts as a dispersive optical medium for the propagation of light. Gravitational rainbows and birefringence replaceExpand
The U(1) Goldberger-Treiman relation and the proton ``spin'': A renormalisation group analysis
Abstract A detailed explanation of the U(1) Goldberger-Treiman relation is presented, and its renormalisation group properties discussed in detail. The implications for the proton “spin” problem areExpand
Conformal anomalies for interacting scalar fields in curved spacetime
The occurrence of anomalies in the trace of the energy-momentum tensor for scalar field theories in curved space-time is discussed. For the special case of spherical space-time, an O(n + 1)Expand
Abstract The theory of the ‘proton spin’ effect proposed in our earlier papers is extended to include the chiral SU (3) symmetry breaking and flavour mixing induced by non-vanishing quark masses inExpand