The symplectic and twistor geometry of the general isomonodromic deformation problem

Hitchin's twistor treatment of Schlesinger's equations is extended to the general isomonodromic deformation problem. It is shown that a generic linear system of ordinary differential equations with gauge group SL(n,C) on a Riemann surface X can be obtained by embedding X in a twistor space Z on which sl(n,C) acts. When a certain obstruction vanishes, the isomonodromic deformations are given by deforming X in Z. This is related to a description of the deformations in terms of Hamiltonian flows on a symplectic manifold constructed from affine orbits in the dual Lie algebra of a loop group.Comment: 35 pages, LATE

A note on the (1, 1,..., 1) monopole metric

Recently K. Lee, E.J. Weinberg and P. Yi in CU-TP-739, hep-th/9602167, calculated the asymptotic metric on the moduli space of (1, 1, ..., 1) BPS monopoles and conjectured that it was globally exact. I lend support to this conjecture by showing that the metric on the corresponding space of Nahm data is the same as the metric they calculate.Comment: 12 pages, latex, no figures, uses amsmath, amsthm, amsfont

Manifolds with holonomy U*(2m)

We consider the geometry determined by a torsion-free affine connection whose holonomy lies in the subgroup U*(2m), a real form of GL(2m,C), otherwise denoted by SL(m,H).U(1). We show in particular how examples may be generated from quaternionic K\"ahler or hyperk\"ahler manifolds with a circle action.Comment: Based on the author's Santalo Lecture delivered in the Universidad Complutense, Madrid on October 10th 2013. To appear in the Revista Matem\'atica Complutens

Management and its public: imagining management practices

This paper suggests that there is value in a conversation between science technology studies and management philosophy. In particular, the paper illustrates how a cocktail of two powerful forces in STS, actor network theory and public understanding of science, can serve to foreground aspects of management hitherto hidden. Actor network theorists persuasively demonstrate that contemporary experience involves human and non-human agents in material and heterogeneous practices. This position leads to a claim that we must increasingly learn to live in tension, as aspects of social life present themselves as full of open ended options that are come to rest either no-where or elsewhere. This paper examines such actor net work concerns through a discussion of agency and raises questions regarding relationships between managerial agency, epistemology of management and public understanding of management. In this context, publics are considered as a legitimate and powerful location through which notions of science and management are coproduced. A case is made for the value of fiction in actor net work studies of organisational behaviour by reference to literature of public understanding of science (PUS). PUS is rendered comparatively relevant here by reference to contextual parallels between science and management such as contemporary challenges to the singular naturalistic narrative, changing social status of disciplinary knowledge and contemporary governance and responsibility debates that impact on day to day practices. In making this comparison it is suggested that whilst it is not uncommon to find a mix of character traits in representations of the contingent and vulnerable human-scientist there is little space for either the vulnerable or heroic manager in popular culture. To close this discussion and offer a point of departure for further discussion this study playfully examines a particular popular fiction Eric (Faust) [Terry Pratchett 1990]. Using material from this fiction, management is reframed in terms of resonance, public understanding of business management and coproduction processes. Finally, this study stops and turns to its readers to continue imaging management and its public