Matrix Models and Lorentz Invariance

The question of Lorentz invariance in the membrane matrix model is addresse

Spiky membranes

We study spiky configurations of membranes in the SO(d)xSU(N) invariant matrix models. A class of exact solutions (analogous to plane-waves) of the corresponding Schroedinger equation for an arbitrary N is discussed. If the large N limit is performed so that the energy scales like N^2, the N=infinity wavefunctions reduce to the ground state of the d-dimensional harmonic oscillator.Comment: 16 pages, 1 figur

Uniqueness of the coordinate independent Spin(9)xSU(2) state of Matrix Theory

We explicitly prove, using some nontrivial identities involving gamma matrices, that there can be only one Spin(9)xSU(2) invariant state which depends only on fermionic variables

Higher-Dimensional Integrable Systems from Multilinear Evolution Equations

A multilinear M-dimensional generalization of Lax pairs is introduced and its explicit form is given for the recently discovered class of time-harmonic, integrable, hypersurface motions.Comment: 5 page

What I Believe

Life is an experience not to be missed. There are the rough spots in life of course, and then there are the smooth stretches when one is at peace with the world. One fine solution for the feeling of depression, insecurity, and futility is to stop and think, Would life be full if it were a life of ease; would life have depth

Uncertainty and risk: politics and analysis

In environmental and sustainable development policy issues, and in infrastructural megaprojects and issues of innovative medical technologies as well, public authorities face emergent complexity, high value diversity, difficult-to-structure problems, high decision stakes, high uncertainty, and thus risk. In practice, it is believed, this often leads to crises, controversies, deadlocks, and policy fiascoes. Decision-makers are said to face a crisis in coping with uncertainty. Both the cognitive structure of uncertainty and the political structure of risk decisions have been studied. So far, these scientific literatures exist side by side, with few apparent efforts at theoretically conceptualizing and empirically testing the links between the two. Therefore, this exploratory and conceptual paper takes up the challenge: How should we conceptualize the cognitive structure of uncertainty? How should we conceptualize the political structure of risk? How can we conceptualize the link(s) between the two? Is there any empirical support for a conceptualization that bridges the analytical and political aspects of risk? What are the implications for guidelines for risk analysis and assessment