Colloquium

From the view of a pure mathematician, those working in pure mathematics produce pure knowledge. Whether used or not, it has a great elegance and value in and of itself. […]

In the 1970s, James O’Keefe and his team observed that certain neurons in the brain, called place cells, spike in their firing rates when the animal is in a particular […]

Understanding how fluid flows through heterogeneous materials, and how it can make these materials fail, are among the hardest challenges in materials science.  Experiments and simulations show that flow through subsurface rock is mostly limited to a small subnetwork, or backbone, of fractures.  Identifying this backbone would allow for a large speedup in flow and […]

Abstract:  A great deal of my research journey has involved the study of m-ary partitions.  These are integer partitions wherein each part must be a power of a fixed integer m > 1.  Beginning in the late 1960s, numerous mathematicians (including Churchhouse, Andrews, Gupta, and Rodseth) studied divisibility properties of m-ary partitions.  In this talk, I will discuss work I completed […]

Abstract: Whether enjoying the lucid prose of a favorite author or slogging through some other writer's cumbersome, heavy-set prattle (full of parentheses, em-dashes, compound adjectives, and Oxford commas), readers will […]

Abstract:  Growing up, I always loved learning about world-changing scientific breakthroughs that were discovered by accident.  Penicillin, artificial sweeteners, X-rays, and synthetic dyes are just a few of the discoveries […]

A lot of the mathematics done at NIST supports the research on and measurement of advanced materials and technology. In this rather applied context. surprising mathematics makes an appearance. We […]

Abstract: As intelligent agents assume larger role in our daily lives, reasoning by humans about liability of such agents as well as reasoning by the intelligent agents themselves about liability […]

Abstract: We overview some basic and striking facts concerning the theory of hypercyclic operators (considered to be born in 1982): 1. Hypercyclicity is a purely infinite-dimensional phenomenon: no finite dimensional space supports any hypercyclic operator; 2. It is not easy at all to determine whether a linear operator is hypercyclic. However, the set of hypercyclic […]

Abstract: "We present a general Bayesian statistical model for discrete time, discrete state space stochastic processes. Applications include the modeling of recurrent and episodic disease processes, such as episodes of illicit drug use, as well as social processes such as educational enrollment and employment. We also present Markov chain Monte Carlo inference algorithms for our […]

Abstract: Mathematical modeling is an effective resource for biologists since it provides ways to simplify, study and understand the complex systems common in biology and biochemistry. Many mathematical tools can be applied to biological problems, some traditional and some more novel, all innovative. This presentation will review the mathematical tools that are used to model […]