Events

We show that when the bare cosmological constant in the Einstein field equations takes large negative values, the average distance between any two nearby geodesics moving in the spacetime sourced by quantum fields vacuum would gradually increase at a slow accelerating rate due to the weak parametric resonance effect caused by the fluctuations of the quantum vacuum energy density. In this scenario, the extreme fine-tuning of the cosmological constant is not needed.

The effort to design and build quantum computers in the laboratory is now a billion dollar enterprise. But might we, ourselves, be quantum computers? Most scientists think that in the warm wet brain, this is highly unlikely; and certainly it would be at variance with what the medical profession believes. My strategy is one of reverse engineering, seeking to identify the biochemical substrate and mechanisms that could host such putative quantum processing.

It is common to think of strains in solids in a somewhat passive sense, simply as the response of a material to external forces. However, for certain types of electronic order, strains of a specific symmetry can have much more important roles to play, acting as longitudinal, and even transverse, fields for the order parameter. In this talk, I will first describe how antisymmetric strain can act as a longitudinal field for electronic nematic order. I'll then go on to describe appropriate transverse fields for nematic order, including orthogonal antisymmetric

Thesis Abstract:
In this thesis, I investigate the behavior of particles dressed by quantum field excitations and random interactions.

The non-zero mass of neutrinos suppresses the growth of cosmic structure on small scales. Since the level of suppression depends on the sum of the masses of the three active neutrino species, the evolution of large-scale structure is a promising tool to constrain the total mass of neutrinos and possibly shed light on the mass hierarchy. I will discuss recent progress and future prospects to constrain the neutrino mass sum with cosmology.

Please join us before the Colloquium in Hennings 318 for coffee, tea and snacks at 2:45 pm

My research program is motivated by fascination with bird flight. My laboratory group uses a multi- disciplinary approach that includes biomechanics, physiology, and neuroscience to examine flight ability. Our current research is organized around two topics: 1) how birds morph their wings and what benefits this provides; and 2) how optic flow signals are encoded in the avian brain and used to guide their flight. As we gain understanding of flight mechanisms, we further endeavor to apply comparative approaches that provide deeper insight into avian ecology and evolution.

Please join us for coffee, tea and snacks before the Colloquium in Hennings 318 at 2:45 pm

In a recent paper, the MIT group led Pablo Jarillo-Herrero has found that doping twisted bi-layer graphene can generate strongly correlated insulating states and superconductivity at particular twist angles called magic angles.  

This problem has excited the condensed matter community because it establishes that graphene, normally viewed as a weakly  interacting system, is a new platform for strongly correlated physics.