Colloquium Series 2019
Colloquium Series 2019
During Session 1 our colloquia will generally be held on Wednesdays at 12pm. Venues will be confirmed prior to each session. Our departmental colloquium series includes speakers from across all physics sub-disciplines, and is intended to be delivered at the senior undergraduate to graduate level, engaging an audience of researchers in areas as diverse as biophysics and astronomy.
For more information or to express interest in giving a talk, Contact: Dr Devika Kamath: firstname.lastname@example.org
Dr Mark Ballico - 22 May 2019
Speaker: Dr Mark Ballico, Section Manager, Mechanical, Thermal and Optical Standards, National Measurement Institute
Venue: Lecture Theatre, Level 1, Australian Hearing Hub
Title: The kg is dead: long live the kg.
Abstract: In May 2019, the SI-System, the framework underpinning all measurement in Physics and Chemistry, underwent a fundamental transformation, bringing to fruition a long held dream first voiced over a century ago by Gauss, Maxwell and Planck, of a unified system linked not to physical artefacts, or even to atomic properties, but to immutable constants of nature. Find out the reasons for this momentous change and its impact on measurement science.
Bio: Dr Ballico completed a PhD in Plasma Physics at the University of Sydney in 1990, and worked as a postdoc in Japan, Germany and the US on thermonuclear fusion. Since 1993 he worked at CSIRO and the NMI, developing primary measurement standards and calibration systems in Temperature, Optical Radiometry and liquid hydrocarbon flow. He is currently responsible for Australia’s leading measurement standards teams in mass and force, temperature, pressure, gas and liquid flow, optical and laser, and acoustics and vibration measurement. His current research interest is using the revised SI to establish temperature standards linked directly to Boltzmann’s constant
Professor Kim Venn - 15 May 2019
Speaker: Professor Kim Venn, Director, Astronomy Research Centre, University of Victoria, BC, Canada
Venue: 7WW, 2.300 Multipurpose Room
Title: Data, Data Analysis, and Machine Learning in Astrophysical Stellar Spectroscopic Surveys
Abstract: To unravel the formation history of the Milky Way, spectroscopic surveys are currently being carried out to gather chemical abundance ratios and kinematic information of stars throughout the Galaxy. High and low resolution spectra of millions of stars are being collected through US, European, and Australian surveys, e.g., GALAH. To have the highest scientific impact, it helps if these
various spectral datasets can be analysed homogeneously. For this reason, a range of data-driven analysis tools have been developed, often combining priors that model the individual spectra and/or the stellar populations. More recently, machine-learning techniques have also been used to examine synthetic spectra and train a neural network for very fast and efficient analyses.
The quality of these results is under constant evaluation, e.g., results from the data-driven approaches are assumed to be drawn from physically sensible features in the stellar spectra, and synthetic spectra are directly compared to observed spectra to evaluate the synthetic gap. I will discuss these methods and surveys, highlighting recent results in the analysis of our Galaxy.
Bio: Kim Venn is Professor in Physics & Astronomy and Director of the Astronomy Research Centre at the University of Victoria, BC, Canada. She is visiting Australia as an ASTRO 3D Distinguished Visitor and Macquarie University Visiting Professor. Her expertise is on the spectral analysis of stars, and she also has strong interests in astronomical instrumentation, machine learning and other data analysis techniques, and is the Director for an industrial-stream NSERC student training program on New Technologies for Canadian Observatories.
Professor Jim Denier - 10 April 2019
Speaker: Professor Jim Denier, Head of Department of Mathematics and Statistics, Macquarie University
Venue: 7WW 149
Title: Fluid mechanics, what's still left to say?
Abstract: Some of you may have heard about fluid mechanics. It’s still hidden in the 02 FORC codes (if you look closely, you’ll find “Fluid Physics” tucked away under Classical Physics). Physics has largely moved on with other pursuits, but fluid mechanics has continued, with the range and variety of application areas still as broad as it was 100 years ago. Many applied mathematicians are interested in fluid mechanics. We use mathematical tools, some of them rather complex, to explore how fluids behave and how we might control them. A good example is in fluid turbulence. As a community we’re now coming to understand much better how turbulence develops and, consequently, how we might design things, such as an aircraft wing, to minimise the impact of turbulence (in the case of an aircraft wing, reducing drag is the aim of the game).
Bio: I’m one of those applied mathematicians! I was drawn to the subject because it was fun, difficult and challenging. I’ve worked on many different aspects of fluid mechanical behaviour over the years, from incompressible fluid flows, through to how waves are generated when water flows over bumps, or dips, in the sea bed. Most recently I’ve been looking at ways in which to use the physics of fluid to help understand how blood flows through umbilical cords. In this talk, I’ll give you some motivation as to why this might be interesting, even important, I’ll show some real experiments (yes, applied mathematicians sometimes do experiments) and try to explain some of the challenges behind taking the physics of fluids from the lab into a clinical setting.
Professor Hans Van Winckel - 27 March 2019
Speaker: Professor Hans Van Winckel, Institute of Astronomy, KU Leuven University, Belgium
Venue: 7WW 149
Title: The Protoplanetary Discs Around Evolved Binaries
Abstract: At the end of their life some binary stars form Keplerian discs of gas and dust with similar properties to the planet-forming discs around young stars (also called protoplanetary discs). Around evolved binaries, these scaled-up versions of protoplanetary discs form as the result of an unconstrained binary interaction process taking place at the end of the giant branch evolution of the initially most massive star. In this talk we will illustrate how we use different observing strategies and different instruments, covering a wide range of wavelengths, as to dissect the systems in their different components. The ultimate goal of our research is to study the binary interaction processes leading to these systems as we observe today, as well as to come to a good prediction on how these systems will evolve.
Bio: Professor Hans Van Winckel is an expert on the observational studies of the late evolution of solar like stars. As an observational astrophysicist, he combines multi-wavelength data obtained with different observational techniques (photometry, spectroscopy, interferometry) to gain insight into the internal structure, nucleosynthesis and binary interaction processes in these stars. He is the programme director of the Master of Astronomy and Astrophysics, at KU Leuven and leads the Mercator observatory at Roque de los Muchachos observatory in Spain.
Professor Eric Emsellem - 13 February 2019
Speaker: Professor Eric Emsellem, European Southern Observatory, Garching
Venue: 9WW 102
Title: Early-type galaxies: climbing to the top of the mass ladder
Abstract: Nearby galaxies display a range of morphologies, sizes, masses, which are the results of a complex set of formation and evolution processes. In this talk, I will focus on early-type galaxies, often split in two classes, the ellipticals and lenticulars, which contain about half of all the stars in our local Universe. I will review our current knowledge of how they form, what are the most important mechanisms which shaped them, and illustrate how our understanding of these objects changed over the last decade via the use of simulations and integral-field spectroscopy. I will then focus on the most massive galaxies, and report on results from numerical simulations and an observational campaign conducted with the MUSE spectrograph, which led to some interesting surprises.
Bio: Eric Emsellem has been at ESO Garching for 10 years. Until recently, Eric was Head of the Office for Science, and is now on a well-deserved 1-yr research sabbatical. Eric had both a theoretical and Engineering background (Paris, Lyon, Cornell) but soon turned to astronomy with a PhD from CRAL-Lyon (France). Eric has contributed or led observational campaigns of nearby galaxies, has developed new tools applied to the dynamical modelling of galaxies and led some efforts to conduct hydrodynamical simulations of galaxies, to further understand how star formation is triggered and proceed.