arXiv subjects

Neil G. Turok

Publications and source records attributed to Neil G. Turok.

4 recordsLinked to original sources

arXiv1998

Exactly Azimuthal Pixelizations of the Sky

We investigate various pixelizations of the sky which allow for fast spherical transforms, for implementation in full sky CMB experiments such as Planck and MAP. We study the effect of varying pixel shape and area on the extraction of the CMB power spectrum. We argue for the benefits of having a truly azimuthal, or `igloo' pixelization. Such pixelizations are simple and allow for fast, exact simulations of pixelized skies. They also allow for precise correction to be made which accounts for the effects of pixel smoothing on extracted multipole moments.

astro-ph↗

arXiv1998

Ringing the eigenmodes from compact manifolds

We present a method for finding the eigenmodes of the Laplace operator acting on any compact manifold. The procedure can be used to simulate cosmic microwave background fluctuations in multi-connected cosmological models. Other applications include studies of chaotic mixing and quantum chaos.

gr-qc↗

arXiv1997

Lattice Chern-Simons Number Without Ultraviolet Problems

We develop a topological method of measuring Chern-Simons number change in the real time evolution of classical lattice SU(2) and SU(2) Higgs theory. We find that the Chern-Simons number diffusion rate per physical 4-volume is very heavily suppressed in the broken phase, and that it decreases with lattice spacing in pure Yang-Mills theory, although not as quickly as predicted by Arnold, Son, and Yaffe.

hep-ph↗

arXiv1997

Classical Field Dynamics of the Electroweak Phase Transition

We investigate the thermodynamics and dynamics of the electroweak phase transition by modelling the infrared physics with classical Yang-Mills Higgs theory. We discuss the accuracy of this approach and conclude that, for quantities whose determination is dominated by the infrared, the classical method should be correct up to parametrically suppressed (ie O(alpha)) corrections. For a Higgs self-coupling which at tree level corresponds to m_H ~ 50 GeV, we determine the jump in the order parameter to be delta phi = 1.5 gT, the surface tension to be sigma = 0.07 g^4 T^3, and the friction coefficient on the moving bubble wall due to infrared bosons to be η= P/v_w = 0.03 \pm .004 g^6 T^4. We also investigate the response of Chern-Simons number to a spatially uniform chemical potential and find that it falls off a short distance inside the bubble wall, both in equilibrium and below the equilibrium temperature.

hep-ph↗