When: Thursday March 22nd 2012

Time: 4:30pm

Where: 2237 French Family Science Building

Title: “Substrate Release From a Sodium Sugar Transporter”

Location: 130 Physics Building

Time: 1:30pm

Title: Transition Path Theory for the Modeling and Simulation of Reactive Processes

Abstract: Transition Path Theory (TPT) is a theoretical framework for describing activated processes and rare events in complex systems. It can also be used as a starting point for developing efficient numerical algorithms for analyzing such processes. Here I will review the basic components of TPT and discuss its connections with the Transition-State Theory, Kramers reaction-rate theory as well as Freidlin-Wentzell theory of large deviations.

I will also discuss how TPT can be used to design efficient path-finding algorithms, such as the string method or the max-flux method, as well as algorithms for free energy and rate  calculations, such as milestoning.

Finally, I will discuss how TPT can be used to build Markov State Models to analyze time-series data.

When:  Thursday February 16th 2012

Where:  French Family Science 2237

Time:  4:00p

Title:  Merging Black-Holes in General Relativity

Abstract: The field of numerical relativity experienced a phenomenal growth spurt during the past six years. The field transformed from one in which the two-body problem, that is the merger of black-hole binaries, was impossible to solve to one where simulations of merging black-holes are now routine. Among the most remarkable discoveries is the one that merging pair of spinning black holes can recoil thousands of km/s, generating very strong emission of gravitational waves in the last few orbits of the collision. The detection these gravitational waves will constitute a major breakthrough in fundamental physics, opening a new window on the universe. For supermassive black-holes in active galaxies, these merger events are also expected to be accompanied by observable electromagnetic signals. In this talk, I will review the latest achievements and highlight the field’s next challenges with emphasis on applications to both gravitational wave and electromagnetic astronomy and astrophysics. I will also present the first magnetohydrodynamics (MHD) calculation of a circumbinary accretion disk around inspiralling supermassive black-holes.

Click here for the beautifully illustrated paper on the talk.

2012 Solar Fuels:  Science, Engineering and Policy

Dates: January 11 & 12, 2012

Venue: R. David Thomas Executive Conference Center at Duke University

CTMS Membership may register for free

A Speaker list and full schedule  http://www.serc.unc.edu/conf

Registration  http://www.tinyurl.com/SERC-Register

Location: 128 Physics Building

Time: 2:00pm

Title: Critical Acceleration

Abstract: In Collisions of ultra-intense laser-pulse with relativistic electrons it is possible to experimentally probe critical acceleration a=mc³/h. The behavior of a particle undergoing critical acceleration challenges the limits of the current understanding of basic interactions: survey of diverse areas of physics, including radiation reaction, the structure and stability of the quantum vacuum, shows that little is known about that new physics frontier, and that both classical and quantum physics will need further development in order to be able to address this newly accessible area of physics. Connection to strong field particle production, Mach Principle, Unruh and Hawking radiation will be discussed.

Rolando Estrada Department of Computer Science

Shishi Luo Department of Mathematics

Samuel Stanton Mechanical Engineering

The Center for Theoretical & Mathematical Sciences (CTMS) is pleased to invite applications from Duke Graduate students for a unique interdisciplinary fellowship in Applied Mathematics or Theoretical Science. Fellowships will provide support (stipend and tuition remission) for Fall 2010 and Spring 2011. Two fellowships will be awarded at this time.

The purpose of these fellowships is to support graduate students whose research interests bridge those of faculty advisors in two different disciplines. Applicants may request support for a project for which traditional support is not available, or for a more typical thesis-directed project. Applicants must be PhD students.

*The critical requirement for the fellowship is that the project establish a link between advisors in different academic departments, one or more of whom will provide mathematical or theoretical expertise and training. It is generally expected that one of the involved supervisors is in a department in Arts & Sciences.

 Each application requires a cv, a description of the student’s project or research program, and letters of commitment of intellectual support for the specific research program from two faculty members under whose guidance the research and/or training will be performed. No other fellowship, RA-ship or TA support may be held concurrent with this award.*

Deadline for applications is May 15, 2010 with award announcements on June 1, 2010 for fellowship support to begin on September 1, 2010. Please apply at Academic Jobs Online https://academicjobsonline.org/ajo/Duke/CTMS/. Faculty members may upload letters of commitment directly to the site. For questions, please contact Liz Labriola,  liz.labriola@duke.edu (919) 684-0881.

Location: 2237 French Family Science Center

Time: 4:30pm

Abstract: Complex systems consist of a large number of mutually interacting agents without leader. Quite often, each agent has only access to limited information (usually about the state of the neighbouring agents). In spite of this, the system as a whole exhibits large scale spatio-temporal coordinated structures such as congestions, waves, oscillations, etc. Some examples of such systems come from traffic problems (cars on highways, pedestrians in corridors or terminals, goods on economical chains). Other examples originate from socially interacting biological entities (insect swarms, fish schools, sheep herds, organs or tumors, etc.). The self-organization behavior is not directed encoded in the local interactions between individuals and emerges when the number of agents is large. After presenting some examples, we will review a certain number of the mathematical problems posed by these systems and in particular the possibility of describing them as a ‘continuum’ or a fluid. This problem is related to the so-called chaos assumption which is the cornerstone of classical statistical mechanics and which states that in a large system, particles are nearly statistically independent.