Concentrated suspensions of hard particles such as cornstarch in water exhibit shear thickening, a non-Newtonian fluid behavior in which an increasing shear rate causes the effective viscosity of the fluid to increase, and even support a load or crack like a solid. Such suspensions can even be strong enough to support a person walking or running on the surface of the fluid. These material properties are promising for applications such as rate-dependent dampers and impact protection.
In 1937 Ettore Majorana introduced the concept of what are now fittingly called Majorana fermions -- fermionic particles that are their own antiparticles. Nowadays an active search for condensed-matter analogues of these elusive objects is well underway, motivated by both the prospect of revealing new facets of quantum mechanics and longer-term quantum computing applications. This talk will survey recent advances in this pursuit.
Most populations are spread over spatial ranges much bigger than any one individual will explore in its lifetime. How does the simple fact of this spatial structure affect adaptive evolution and genetic diversity?
I will discuss when space can slow down or speed up adaptation, how adaptation in spatially structured populations restructures even the neutral genetic variation, and how we might be able to use sequencing data as a lens to watch organisms move.