289 research outputs found
Geraint N. D. Evans
No full text Geraint Evans was killed last Christmas in a car accident in California. He was thirty-six. I had been in touch with him by telephone only a few days earlier, and I shall never forget the incredulity I felt when his widow, Ursula, wrote to tell me of his death. He was one of the most vital, ener- getic, mobile and tempestuous men I had ever known, and his passing seemed an insult to nature. </jats:p
Danish Departed
No full textSolo exhibition of paintings and drawings by Alastair John Gordon at Husk Gallery, Departure, London curated by Geraint Evans.
Texts published in connection with this exhibition: ‘Danish Departed’ by Geraint Evans; ‘A Little Bit of Denmark’ by Gary Haines, archivist at the Whitechapel Gallery, London
David Jones and the matter of Wales
No full textEvans Geraint. David Jones and the matter of Wales. In: Etudes Celtiques, vol. 29, 1992. Actes du IXe congrès international d'études celtiques. Paris, 7-12 juillet 1991. Deuxième partie : Linguistique, littératures. p. 456
The Abject Object
No full textA group exhibition curated by Geraint Evans that explores contemporary painterly representations of objects with reference to the still life tradition and with a particular interest in the notion of thingness and abjection.
The starting point is Norman Bryson’s description of still life as “…an object world that has dispensed with human attention and in a sense makes human attention and the human subject obsolete.” The exhibition is concerned with the ways in which paint’s materiality resonates with meaning and articulates the relationship between subject and object, the observer and the observed.
Artists include: Sophie Birch,
G L Brierley, Simon Callery, Mark Fairnington, Ana Genovés, John Greenwood, Paul Housley, Damien Meade and Donal Moloney.
Panel discussion: was held on Thursday 12 May 4.30-6.30pm in the lecture theatre at Wimbledon College of Arts to discuss and debate the issues raised by the exhibition.
Participants included curator Geraint Evans, Course Leader for MA Painting at Wimbledon; Mark Fairnington, participating artist and Reader in Painting CCW; Frances Woodley, artist, academic and curator of exhibitions ‘All Coherence Gone? Historical currents in contemporary still life’ 2014 and ‘Still Life: Ambiguous Practices’ 2015; Dr Fiona Candlin, Senior Lecturer in Museum Studies at Birkbeck University of London and co-author of ‘The Object Reader’ and painter Damien Meade, recent exhibitor in the London Open, Whitechapel Gallery, London 2015
Chiral Soliton Lattice turns into 3D crystal
No full textAbstract Chiral perturbation theory predicts the chiral anomaly to induce a so-called Chiral Soliton Lattice at sufficiently large magnetic fields and baryon chemical potentials. This state breaks translational invariance in the direction of the magnetic field and was shown to be unstable with respect to charged pion condensation. Improving on previous work by considering a realistic pion mass, we employ methods from type-II superconductivity and construct a three-dimensional pion (and baryon) crystal perturbatively, close to the instability curve of the Chiral Soliton Lattice. We find an analogue of the usual type-I/type-II transition in superconductivity: along the instability curve for magnetic fields eB > 0.12 GeV2 and chemical potentials μ < 910 MeV, this crystal can continuously supersede the Chiral Soliton Lattice. For smaller magnetic fields the instability curve must be preceded by a discontinuous transition
Strange quark mass turns magnetic domain walls into multi-winding flux tubes
No full textDense quark matter is expected to behave as a type-II superconductor at strong coupling. It was previously shown that if the strange quark mass ms is neglected, magnetic domain walls in the so-called 2SC phase are the energetically preferred magnetic defects in a certain parameter region. Computing the flux tube profiles and associated free energies within a Ginzburg–Landau approach, we find a cascade of multi-winding flux tubes as 'remnants' of the domain wall when ms is increased. These flux tubes exhibit an unconventional ring-like structure of the magnetic field. We show that flux tubes with winding numbers larger than one survive for values of ms up to about 20% of the quark chemical potential. This makes them unlikely to play a significant role in compact stars, but they may appear in the QCD phase diagram in the presence of an external magnetic field
Superconducting phases of strongly-interacting matter in large magnetic fields.
No full textThe large magnetic fields of neutron stars and produced in heavy-ion collisions motivate investigation into the response of strongly-interacting matter to extreme magnetic forces beyond just theoretical interest. Furthermore, the varying temperature T, baryon chemical potential μB, and aforementioned magnetic fields B, of these systems leads to questions concerning the phase structure of Quantum Chromodynamics (QCD) at large. At low temperatures, superconducting phases become a possible candidate for the ground state in the μB-B plane. This thesis investigates two scenarios where these phases emerge at T=0, with an emphasis on the type-II regime. The first scenario concerns type-II superconductivity at large μB. At asymptotically high baryon density the ground state of QCD is a colour superconductor where gluonic fields can experience a Meissner effect. In the two-flavour pairing (2SC) and colour-flavour locked (CFL) colour-superconducting phases, a small admixture of the photon with a gluon is also expelled which means an applied external magnetic field will experience a slight Meissner effect. Therefore, these phases act as very weak electromagnetic superconductors. Previous works have shown that with massless quarks the type-II 2SC phase is preferred in a certain parameter region where the magnetic defects are domain walls. We introduce corrections for a finite strange quark mass in a Ginzburg-Landau approach, and find that the domain wall defects are replaced by a cascade of multi-winding flux tubes, among other changes to the phase diagram. Due to the emergence of a second colour-superconducting condensate emerging in the core, the magnetic flux is confined into "rings'' where both condensates are depleted, forming pipe-like structures. In the second scenario, μB is low enough such that the presence of nucleons is not yet energetically favourable. It was previously shown that, using Chiral Perturbation Theory and incorporating the chiral anomaly via a Wess-Zumino-Witten term, the ground state in this region above a certain critical magnetic field is a Chiral Soliton Lattice (CSL) of neutral pions - an inhomogeneous phase consisting of a series of domain walls. It was further shown that the CSL becomes unstable to charged pion fluctuations at an even higher second critical field. We argue this instability corresponds to a second order phase transition to a type-II superconducting vortex lattice phase and construct this phase in the chiral limit. We find the type-II vortex lattice phase is preferred and has a non-zero, inhomogeneous baryon number density, leading to a two-dimensional crystalline structure. Preceding the presentation of these works, the μB-B plane of the QCD phase diagram is reviewed such that the results can be placed in the wider context of this plane
Chiral anomaly induces superconducting baryon crystal
No full textIt was previously shown within chiral perturbation theory that the ground state of QCD in a sufficiently large magnetic field and at nonvanishing, but not too large, baryon chemical potential is a so-called chiral soliton lattice. The crucial ingredient of this observation was the chiral anomaly in the form of a Wess-Zumino-Witten term, which couples the baryon chemical potential to the magnetic field and the gradient of the neutral pion field. It was also shown that the chiral soliton lattice becomes unstable towards charged pion condensation at larger magnetic fields. We point out that this instability bears a striking resemblance to the second critical magnetic field of a type-II superconductor, however with the superconducting phase appearing upon increasing the magnetic field. The resulting phase has a periodically varying charged pion condensate that coexists with a neutral pion supercurrent. We construct this phase analytically in the chiral limit and show that it is energetically preferred. Just like an ordinary type-II superconductor, it exhibits a hexagonal array of magnetic flux tubes, and, due to the chiral anomaly, a spatially oscillating baryon number of the same crystalline structure
Perceiving landscape: a cultural act and aesthetic experience
No full textA keynote lecture that discussed the notion of landscape as a cultural construct. Geraint Evans discussed the perception of nature within towns and suburbs; within gardens (with reference to the English landscape garden tradition), and parks; in relation to tourism (national parks, theme parks and walking clubs) and, discussed the perception of wilderness. The presentation largely agrees with Malcolm Andrews assessment that “Landscape, which has long meant either the real countryside or the pictured representation of it, is in effect the combination of the two.
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