Fluid Physics at the Molecular Scale

The image shows flagella driven by dynein molecular motors. The vectors show the position and time-dependent velocity.  There is also a graph of the body velocity. Note the desychronization event.

This work comes from Adjunct Professor Jerry Gollub's lab.


Jammed States of Matter

Almost any system composed of discrete pieces large enough that thermal fluctuations can be ignored can have a jamming transition: a point at which fluid flow is impeded by a change of state into a stable amorphous solid.  The behavior is general enough to explain a pile of sand, a jar of candies, or cars in a traffic jam.  Professor Andrea Liu was involved in recent theoretical breakthroughs in the study of this phenomenon.


Dark Energy Studies

Professor Masao Sako uses Type Ia supernovae to study the expansion history of the universe.  The graphs show (left and middle) Hubble diagrams from a simulated 5-year Type Ia sample from the Dark Energy Survey.  The right graph shows the 95% confidence limits on dark energy parameters.

Dark Energy Survey

The Dark Energy Survey (DES) uses a 570-Megapixel digital camera at the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory in the Chilean Andes to probe the origin of the accelerating universe. Penn scientists are among the 120 scientists from 23 institutions in the US, UK, Brazil, and Germany working on the project slated for first light in Fall 2012.


DNA-Functionalized Carbon Nanotube Chemical Sensors

The group of Professor Charlie Johnson has developed chemical sensors using single-walled carbon nanotubes wrapped with single-stranded DNA adsorbed to the nanotube's outer wall.