Saturday 31 July 2010

Recent and Upcoming Seminars

Upcoming Seminars

Great is the Power of Steady Misrepresentation
Prof Ian Enting
MASCOS/Department of Mathematics and Statistics, The University of Melbourne
Start time: 3:15 pm
Date: Monday 2 August 2010
Location: Theatre 1, Alan Gilbert Building (bldg 104), The University of Melbourne (cnr Grattan St and Barry St).

The science of climate change has come under public attack through what has been described as asymmetric warfare. Public communication has been flooded with a deluge of misinformation. In parallel there have been attempts to distract, intimidate and gag climate scientists. In 2009 Ian Plimer's book, "Heaven+Earth - Global Warming: The Missing Science", claimed to demolish the theory of human-induced global warming due to the release of CO2 and other greenhouse gases. A careful reading of "Heaven + Earth" reveals extensive examples of fabricating numbers, distorted and misattributed graphics, misrepresentation of the content of cited references and a sprinkling of plagiarism. In spite of its blatant flaws, "Heaven+Earth" has gained considerable political traction in Australia.

Past Seminars

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Techniques of Constraint Integer Programming
Timo Berthold, Zuse Institute Berlin (ZIB) and MATHEON (Berlin)

Start time: 3:15 pm
Date: Friday 29 January 2010
Location: Theatre 2, ICT Bldg (ground floor, 111 Barry Street)

Abstract: Mixed-integer programming (MIP) and constraint programming CP) proved to be a powerful tools to model and solve large-scale optimization problems. Constraint integer programming (CIP) is a novel generalization of MIP that supports the notion of arbitrary constraints as in CP. We introduce the basic notion and algorithmic ideas of CIP. Further, we present the software SCIP which is a solver and framework for constraint integer programming that also features SAT solving techniques.

Chaos expansion of Poisson functionals
Prof. Guenter Last
Karlsruhe Universitaet (TH)
Start time: 3:15 pm
Date: Friday 4 September 2009
Location: Theatre 1, ICT Bldg (ground floor, 111 Barry Street, Carlton)

In the first part of the talk we recall the definition of a Poisson process on a general state space and discuss some basic properties of this process (random measure). Then we proceed with deriving an explicit Fock space representation for Poisson processes in terms of iterated difference operators. Finally we apply this result to get an explicit version of the Wiener-Ito chaos expansion and variance inequalities.

The talk is based on joint work with Mathew Penrose (Bath).

Littlewood's Conjecture
Professor Andrew Pollington
Director for the Algebra, Number Theory and Combinatorics panel
National Science Foundation, Division of Mathematical Sciences
Start time: 12:00 pm
Date: Thursday 3 September 2009
Location: Prince Philip Theatre, Architecture and Planning Building (Ground Floor), The University of Melbourne

Experimental Mathematics Meets Mathematical Physics
David H Bailey
Lawrence Berkeley Laboratory, USA
Start time: 3:15 pm
Date: Thursday 20 August 2009
Location: Old Geology Theatre 1, The University of Melbourne

High-precision arithmetic has been called the "electron microscope" of experimental mathematics. The general approach is to compute some mathematical expression to very high precision (typically several hundred digits) for some specific choice of parameters, then apply an integer relation algorithm such as "PSLQ" to find a relation linking this object or expression and other known mathematical entities. Relations and formulas that are numerically discovered in this manner must then be proven rigorously.

One particularly fruitful area for this methodology is the evaluation of definite integrals, such as those that arise in mathematical physics. Literally hundreds of new and intriguing results, specific and general, have been found in this manner, including results in Ising theory, quantum field theory and even computational biology. Progress in this arenas has been hampered by long run times required to evaluate high-dimensional integrals. However, with the increasing availability of highly parallel computer systems, many of these integrals can now be evaluated. Nonetheless, new techniques are required to further advance the state of the art.

Wild emergence of complex organisation in a simple cellular automata
Tony Smith
Complex Systems Analyst, Meme Media
Start time: 3:15 pm
Date: Friday 1 May 2009
Location: Theatre 1, ICT Building (Ground Floor, 111 Barry Street, Carlton)

Six months intense study of the development from simple seeds with the Generations 345/3/6 cellular automata rule has revealed a vast new territory of emergent phenomena and a limitless supply of data on the behaviour of complex interactions extremely close to the elusive boundary of order and chaos. Viable seed patterns form a slowly growing chaotic core with outbound streams of 1/2 speed (space)ships headed NSEW. Around once per million live cells, one of several varieties of also 1/2 speed track/trail laying engines appears, surviving indefinitely within the ship streams. The tracks and trails exhibit resilience, even healing, and support a range of attached patterns moving at various fractional speeds. Those attached patterns and subsequent interactions with ships in the streams provide numerous different mechanisms for initiating new chaotic cores far from the original core. Most important reactions exhibit phase dependent variability making them computationally irreducible and attractive for statistical analysis despite being fully deterministic.

Further information and links:
Golly, an open source, cross-platform application for exploring the Game of Life and other cellular automata: http://golly.sf.net/
Current placeholder page for this project which is to be developed in the months to come: http://www.TheWildCA.com/
Some uneven commentary, pics and animations from the last six months: http://www.transforum.net/m.cgi?num=2779
As yet only one animation is on YouTube: http://www.youtube.com/watch?v=qh_DE_EXNGE
2003 essay on Border of Order–Edge of Chaos: http://www.meme.com.au/theoria/retreat.html
2004 evolving network project that is the only non CA amongst my six discrete system investigations: http://www.twistet.com/
Melbourne Emergence Meetup, 2nd Thursday of the month at The Corkman: http://emergence.meetup.com/24/

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