Events

## SMARTech Video Archive

May

01

We will address some basic questions related to the light forces on small (Rayleigh) particles, which are usually described as the sum of two terms: the dipolar or gradient force and the scattering or radiation pressure force. The scattering force is traditionally considered proportional to the Poynting vector, which gives the direction and magnitude of the momentum flow. However, as we will show, when the light field has a non- uniform spatial distribution of spin angular momentum there is an additional non-conservative force term is proportional to the curl of the spin angular momentum of...

Apr

24

Nonlinear dynamics has the feature that it is conceptually and mathematically challenging and yet ubiquitous in its applications. Indeed, one of the appeals of the subject is the universality of some of its frameworks and results. We are attempting to take advantage of such wide applicability in order to involve an unusual range of participants in nonlinear dynamics research. This range spans from postdoctoral to K-12 students as well as teachers.

Apr

23

Cavity optomechanics is rapidly developing into a major area of research. This is a result of the developments from two converging perspectives on the physical world. From the top down perspective, ultra-sensitive micromechanical and nanomechanical detectors have become available utilizing the advanced materials and processing techniques of the semiconductor...

Apr

20

I will give an overview of a program to map the space of configurations of binary compact coalescences, starting for preliminary indications a couple of years ago that the problem is amenable to reduced order modeling. I will then give an overview of Reduced Basis, our results obtained so far and a roadmap for the future. Essentially, the core issue is how to chose the most relevant points in parameter space, in a nearly optimal way, and to select which configurations are "the most representative ones". This applies to the case in which the emitted gravitational waves can be simply evaluated using closed form approximations or obtained by solving simple equations but,...

Apr

19

Biosketch: Dr. David Ballantyne obtained his Ph.D. in 2002 from the University of Cambridge, and has been an Assistant Professor at the

Center for Relativistic Astrophysics in the School of Physics since 2008. His research concentrates on topics in high-energy astrophysics

with an emphasis on interpreting existing data and making predictions for future observations. His main interests are the evolution of

galaxies and their central supermassive black...

Apr

19

Extreme-mass-ratio binaries, composed of a small compact object (SCO) and supermassive black hole (SMBH), are eventual observational candidates for future space-based gravitational wave observatories. Theoretically, these binaries are examples of the as-yet not thoroughly solved two-body problem in general relativity. Extreme-mass-ratio inspiral (EMRI) calculations proceed by using black hole perturbation theory. The gravitational field of the small mass affects its own orbit in the background geometry,...

Apr

18

Sebastian Thrun recently left Stanford University and started Udacity. Udacity is an online university that seeks to reach the 99% of the world population that are presently excluded from high-quality higher education. The first class on Artificial Intelligence, jointly offered with Stanford, attracted 160,000 students, of which 23,000 graduated with Stanford-level qualifications. The speaker will discuss his experience with traditional forms of education, and brainstorm how higher education may look like in the digital age.

Thrun is co-founder of Udacity, a Google VP, and a Stanford Research Professor. At Google, he runs Google X, home to the Google self-driving car...

Apr

17

In this talk we will focus on the elasticity of soft filamentous networks. We will begin with the mechanical behavior of fibrin networks which

have been shown to be highly extensible in recent experiments. We believe that the high extensibility of the networks has its origins in the force induced

structural change in the proteins making up the fibrin fibers. We will present a model and experimental evidence in support of our hypothesis. In the

remainder of the talk we will describe how the quasi-harmonic approximation of statistical mechanics can be combined with the finite element method (used

in structural analysis of buildings,...

Apr

16

Apr

11

Understanding the new states at the interfaces and the resulting whole behavior of the heterostructures and multilayers is a hot topic at the forefront of the fundamental research, as demonstrated by the huge number of theoretical and experimental studies published in the topmost level scientific journals. In this context, s...

Apr

09

Joseph Ford saw beauty in "Chaos" and the potential for ``villainous chaos" to be used in a constructive manner. His ideas have proved prescient. The talk will focus mainly on how chaotic dynamics may have played a key constructive -- rather than destructive -- role in shaping certain features of the Kuiper belt: in particular, the formation and properties of binary objects in the transneptunian part of the Solar System. Kuiper belt binaries stand out from other known binary objects in having a...

Apr

05

Bulk Topological Insulators are a new phase of electronic matter which realizes a non-quantum-Hall-like topological state in the bulk matter and unlike the quantum Hall liquids can be turned into superconductors. In this Lecture, I will first review the basic theory of topological matter and...

Apr

03

The workshop will provide a general introduction into numerical relativity and in code development within large collaborations. The number of addendees are limited, and while registration is free, it is required. In order to register, write an email to workshop@einsteintoolkit.org.

Apr

03

I describe a unified approach to locating key material transport barriers in unsteady flows induced by two-dimensional, non-autonomous dynamical systems. Seeking transport barriers as minimally stretching material lines, one obtains that such barriers must be shadowed by minimal geodesics under the metric induced by the Cauchy-Green strain tensor field associated with the flow map. As a result, snapshots of transport barriers can be explicitly computed as trajectories of ordinary differential equations. Using this approach, hyperbolic barriers (generalized stable and unstable manifolds), elliptic barriers (generalized KAM curves) and parabolic barriers (...