Blow up dynamics for smooth equivariant solutions to the energy critical Schr\"odinger map

We consider the energy critical Schr\"odinger map problem with the 2-sphere target for equivariant initial data of homotopy index $k=1$. We show the existence of a codimension one set of smooth well localized initial data arbitrarily close to the ground state harmonic map in the energy critical norm, which generates finite time blow up solutions. We give a sharp description of the corresponding singularity formation which occurs by concentration of a universal bubble of energy

The GSI oscillation mystery

In this talk, a short discussion of the GSI anomaly is given. We discuss the physics involved using a comparison with pion decay, and explain why the observed oscillations cannot be caused by standard neutrino mixing.Comment: 3 pages, 1 figure; part of the proceedings of the "International School of Nuclear Physics, 31st Course, 'Neutrinos in Cosmology, in Astro-, Particle- and Nuclear Physics' " in Erice, Italy, 16 - 24 September 200

Stable self similar blow up dynamics for slightly L^2 supercritical NLS equations

We consider the focusing nonlinear Schr\"odinger equations $i\partial_t u+\Delta u +u|u|^{p-1}=0$ in dimension $1\leq N\leq 5$ and for slightly $L^2$ supercritical nonlinearities p_c with $p_c=1+\frac{4}{N}$ and 0<\e\ll 1. We prove the existence and stability in the energy space $H^1$ of a self similar finite time blow up dynamics and provide a qualitative description of the singularity formation near the blow up tim

Motivational factors and the experience of learning in educational leisure settings

Motivation is an important aspect of learning in educational leisure settings because it affects the choices visitors make regarding what to attend to, the amount of effort they devote to learning, and the extent to which they enjoy the experience. Commonly, however, visitors seek entertainment, social or restorative experiences as well as, or in preference to, a learning experience. This research investigates the impact of motivational factors on the experience of learning in educational leisure settings. Motivational factors are considered in terms of four components - personal goals, capability beliefs, context beliefs and situational incentives. The experience of learning is considered in terms of visitors’ perceptions of the experience, rather than objective measures of learning outcomes, as the experience itself is seen as the desired outcome of the visit. Visitors to six different educational leisure settings in South East Queensland were invited to participate in the research, including a museum, an art gallery, a wildlife centre, an aquarium, and guided tours of natural and cultural heritage sites. Quantitative and qualitative data were collected using questionnaires (499 participants) and interviews (52 participants) in order to ascertain the importance to visitors of different types of learning experiences; identify the extent to which motivations for learning vary across sites and visitor groups; investigate the relationships between the educational, entertainment, social and restorative aspects of the visitors’ experience; and examine the impact of motivational factors on visitors’ experience of learning in leisure settings. The findings support the importance of learning to visitors in a range of educational leisure settings. Visitors seek an experience that combines elements of learning and discovery, and is perceived to be both effortless and fun. It is concluded that the characteristics of learning in educational leisure settings contribute to a synergy between the educational and entertainment aspects of the experience. Situational factors are more important than personal factors in motivating visitors to engage in and experience this type of learning. This is of great significance to educational leisure settings as it implies that sites have a reasonable degree of control over the motivational factors that influence visitor engagement in learning

On collapsing ring blow up solutions to the mass supercritical NLS

We consider the nonlinear Schr\"odinger equation i\pa_tu+\Delta u+u|u|^{p-1}=0 in dimension $N\geq 2$ and in the mass super critical and energy subcritical range $1+\frac 4N<p<\min\{\frac{N+2}{N-2},5\}.$ For initial data $u_0\in H^1$ with radial symmetry, we prove a universal upper bound on the blow up speed. We then prove that this bound is sharp and attained on a family of collapsing ring blow up solutions first formally predicted by Gavish, Fibich and Wang.Comment: 48 page

The minimum wage law in Massachusetts

Thesis (M.A.)--Boston Universit