Revisiting the 18th century sublime in contemporary visual art:representations of Icelandic landscape

This thesis discusses the depiction of the landscape in art in relation to the theory of the sublime, through my own artistic practice, and through the examination of examples from the history of art. The theory of the Sublime is also analysed in the historical context of the18th century, and discussed in relation to its place, and relevance in contemporary ideas and art production. The thesis begins by examining Edmund Burke’s Philosophical Enquiry into the origin of our ideas of the Sublime and Beautiful, and using this to explore how artists have responded to the Sublime in their paintings, examining the work of Turner and Caspar David Friedrich for example, as major exponents of the Sublime. I set out to establish whether or not the emotional qualities that the eighteenth-century idea of the Sublime uncovers, can be effectively defined by this term in contemporary painting. Alongside this, my thesis also deals with my own personal experience of the Sublime, as identified in the glacial landscapes of Iceland. The Sublime is a key influence in my artistic practice. My paintings might be seen as a direct response to feelings associated with the Sublime experienced in the glacial landscapes of Iceland, and through the process of making them I have attempted to explore and translate my sublime experience

Ion-scale spectral break of solar wind turbulence at high and low beta

The power spectrum of magnetic fluctuations in the solar wind at 1 AU displays a break between two power laws in the range of spacecraft-frame frequencies 0.1 to 1 Hz. These frequencies correspond to spatial scales in the plasma frame near the proton gyroradius ρi and proton inertial length di. At 1 AU it is difficult to determine which of these is associated with the break, since [Formula: see text] and the perpendicular ion plasma beta is typically β⊥i∼1. To address this, several exceptional intervals with β⊥i≪1 and β⊥i≫1 were investigated, during which these scales were well separated. It was found that for β⊥i≪1 the break occurs at di and for β⊥i≫1 at ρi, i.e., the larger of the two scales. Possible explanations for these results are discussed, including Alfvén wave dispersion, damping, and current sheets

Solar Wind Electric Fields in the Ion Cyclotron Frequency Range

Measurements of fluctuations of electric fields in the frequency range from a fraction of one Hz to 12.5 Hz are presented, and corrected for the Lorentz transformation of magnetic fluctuations to give the electric fields in the plasma frame. The electric fields are large enough to provide the dominant force on the ions of the solar wind in the region near the ion cyclotron frequency of protons, larger than the force due to magnetic fluctuations. They provide sufficient velocity space diffusion or heating to counteract conservation of magnetic moment in the expanding solar wind to maintain nearly isotropic velocity distributions

Detailed Structure and Dynamics in Particle-in-Cell Simulations of the Lunar Wake

The solar wind plasma from the Sun interacts with the Moon, generating a wake structure behind it, since the Moon is to a good approximation an insulator, has no intrinsic magnetic field and a very thin atmosphere. The lunar wake in simplified geometry has been simulated via a 1-1/2-D electromagnetic particle-in-cell code, with high resolution in order to resolve the full phase space dynamics of both electrons and ions. The simulation begins immediately downstream of the moon, before the solar wind has infilled the wake region, then evolves in the solar wind rest frame. An ambipolar electric field and a potential well are generated by the electrons, which subsequently create a counter-streaming beam distribution, causing a two-stream instability which confines the electrons. This also creates a number of electron phase space holes. Ion beams are accelerated into the wake by the ambipolar electric field, generating a two stream distribution with phase space mixing that is strongly influenced by the potentials created by the electron two-stream instability. The simulations compare favourably with WIND observations.Comment: 10 pages, 13 figures, to be published in Physics of Plasma