Fractals are patterns that repeat at many magnifications. These intricate patterns are found throughout nature, ranging from clouds, rivers and lightning through to our brains, blood vessels and lungs. Due to their prevalence in nature and their growing impact on cultures around the world, fractals have assumed a rapidly expanding role across the sciences and arts. In this talk, I will explore some of the intriguing properties of fractals by taking a meandering walk through the research disciplines I have worked in. These will include nano-electronic circuits, Antarctic ice-shelves, brain structure and artworks. I hope to show a common theme - that quantification of their underlying fractal geometry provides an enhanced understanding well beyond the traditional qualitative views of these diverse systems.

White dwarf stars are the burnt out remnants that remain after a star like the Sun has completed its nuclear evolution. In such a star there are no remaining nuclear energy sources, so the star evolves by simply radiating its stored thermal energy out into space. This may seem rather uninteresting, but in fact there is a wealth of physical phenomena that occur during this part of a star's life - from getting kicked at birth, to neutrino emission in early life, to some interesting high density physics, through to functioning as precise clocks that can provide an age for some of the oldest know stars in the Universe. Some of these phases will be illustrated with detailed observations taken recently with the Hubble Space Telescope.

Dark matter and dark energy clearly emerged from recent cosmological surveys as key ingredients of the Universe. Understanding their physical nature might be a way to unlock some of the mysteries in particle physics and General Relativity. In this talk I will discuss how gravitational lensing will have a unique contribution in this endeavor. I will also discuss how future weak lensing surveys, primarily designed to study dark matter and dark energy, will enable the detailed analysis of the physical processes underlying structure formation such as galaxies and clusters of galaxies. Presented on April 10, 2008.

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The universe is filled with a thermal glow called the cosmic microwave background that comes from the hot plasma which filled it early on. Measurements of this background made by the NASA satellite WMAP have determined the age, geometry and composition of the universe with new precision, determining that the universe today is dominated by a dark energy that is causing it to expand ever more rapidly. The mission has also determined that baryonic matter--the atoms and molecules we see around us--only form a few percent of the total energy density of the universe today, and has determined the epoch at which the first stars formed. Recent results give a tantalizing picture of the first very small fraction of a second in the "big bang". Six years after its launch WMAP remains healthy and the data continue to pour in. This talk will explain to a general audience what this experiment tells us about how the universe began and what it is made out of.

This presentation was one of several presentations delivered at the First International Open Access Day event held on October 14, 2008 at UBC. In support of the open access movement, the UBC Library joined with SPARC, PLoS (Public Library of Science), and Students for FreeCulture along with 65 other institutions in celebration of this worldwide event.

This presentation was one of several presentations delivered at the First International Open Access Day event held on October 14, 2008 at UBC. In support of the open access movement, the UBC Library joined with SPARC, PLoS (Public Library of Science), and Students for FreeCulture along with 65 other institutions in celebration of this worldwide event.

This presentation was one of several presentations delivered at the First International Open Access Day event held on October 14, 2008 at UBC. In support of the open access movement, the UBC Library joined with SPARC, PLoS (Public Library of Science), and Students for FreeCulture along with 65 other institutions in celebration of this worldwide event.

This presentation was one of several presentations delivered at the First International Open Access Day event held on October 14, 2008 at UBC. In support of the open access movement, the UBC Library joined with SPARC, PLoS (Public Library of Science), and Students for FreeCulture along with 65 other institutions in celebration of this worldwide event.

We have released maps and data for five years of observation of the cosmic microwave background with the Wilkinson Microwave Anisotropy Probe (WMAP) and I will review the main results in this talk. A simple 6 parameter cosmological model continues to be an excellent fit to the CMB data and to our data in conjunction with other astrophysical measurements. In particular a running spectral index is not supported by the data, and constraints that the Universe is spatially flat have increased in precision. Increased sensitivity and improvements in our understanding of the instrumental beam shape have allowed us to measure for the first time a cosmic neutrino background. Neutrinos de-coupled from other matter earlier than photons did. While they are expected to have a 2 Kelvin thermal distribution today, they comprised 10% of the energy density of the Universe at the epoch of photon de-coupling. The data also allow tighter constraints on the shape of the inflationary potential via the amplitude of a gravitational wave background new constraints on features of cosmic axions. Recorded at TRIUMF on Thursday April 17, 2008.