On relativistic discs and rings

Sequences of infinitesimally thin, uniformly rotating, self-gravitating relativistic discs with internal two-dimensional pressure have been constructed. It is shown that in weaker relativistic configurations the sequences undergo a continuous bifurcation from a disc to a ring structure, while in stronger relativistic cases the sequences terminate at the mass-shed limit where gravitational forces are exactly balanced by centrifugal forces.Comment: 9 pages, requires mn.sty and epsf.sty, 12 figures included, accepted by Monthly Notices of the Royal Astronomical Societ

Far distant, far distant: Orwell, my father & Catalonia

Reflections on the current situation in Catalonia with reference to George Orwell's Homage to Catalonia and James Maley's experiences with the International Brigades in 1937, dramatized in the play, From the Calton to Catalonia, by John & Willy Maley

A Recursive Scheme of First Integrals of the Geodesic Flow of a Finsler Manifold

We review properties of so-called special conformal Killing tensors on a Riemannian manifold $(Q,g)$ and the way they give rise to a Poisson-Nijenhuis structure on the tangent bundle $TQ$. We then address the question of generalizing this concept to a Finsler space, where the metric tensor field comes from a regular Lagrangian function $E$, homogeneous of degree two in the fibre coordinates on $TQ$. It is shown that when a symmetric type (1,1) tensor field $K$ along the tangent bundle projection $\tau: TQ\to Q$ satisfies a differential condition which is similar to the defining relation of special conformal Killing tensors, there exists a direct recursive scheme again for first integrals of the geodesic spray. Involutivity of such integrals, unfortunately, remains an open problem.Comment: This is a contribution to the Proc. of workshop on Geometric Aspects of Integrable Systems (July 17-19, 2006; Coimbra, Portugal), published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA

Spenser and Europe: Britomart after Brexit

No abstract available

The early years of innovative approaches to youth information and counselling

This chapter focuses on the innovative services set up for the specific purpose of giving social support to young people by means of information and counselling in youth information and counselling services. These innovative services originated roughly from the mid sixties and developed particularly after 1980