Ice in the environment, particularly snow, has long drawn the interest of naturalists and captured the imagination of people all over the world. But ice is no mere curiosity. Ice crystals in the atmosphere play important roles in lightning, rain initiation, ozone depletion, planetary reflectivity, and water transport. Over the years, the unique structural, electrical, and chemical properties of ice have attracted the minds of scientists such as Bridgeman, Pauling, and Onsager. Yet many mysteries of ice still elude us. One such mystery is the crystal habit problem: What causes ice to grow in a needle shape at one temperature, yet grow as a six-cornered dendrite only a few degrees colder? Understanding this and related behavior will be crucial to improving quantitative predictions about weather and climate problems. In this talk, I describe how a serendipitous discovery in the lab helped resolve part of the long-standing habit problem and why ice physics will likely remain a fertile research area for physicists and chemists for many years to come.

Speckle is a ubiquitous phenomena in all modes of coherent imagery, be it optical, ultrasonic or x-ray.  For most people, speckle is a noise problem that degrades the quality of images and an annoying issue that simply must be dealt with.  For others, speckle is a rich source of information about the physics of the object being imaged.  This talk will take the latter viewpoint.  The dynamic behavior of laser speckle originating from soft condensed matter, including biological tissues, provides clues about the physical, mechanical, and biochemical nature of the matter at scale sizes ranging from the molecular domain up to the level of multi-cellular architecture.  In this talk, the physical origins of laser speckle along with a variety of experiments in which laser speckle is exploited to reveal the nature of biological structures and other forms of soft condensed matter will be discussed. 

Nanostructures are becoming increasingly important as technological components for applications ranging widely from sensors and photonics to energy harvesting, and even conventional electronic devices.  Even so, much of the science of the nanoscale still remains observationally based and generally empirical.  Nevertheless, there are a number of research efforts directed toward modeling at the atomic scale and consequent understanding of nanoscale physics.  This includes everything from sophisticated quantum mechanics to simple “ball-and-stick” models.  However, classical thermodynamic concepts have not been widely applied to nanostructures.  The reason for this is quite simple: conventional thermodynamics is conceptually limited to macroscopic systems.  This is both a strength and weakness.  Indeed, because the underlying microscopic physics is generally treated in an grossly averaged sense, thermodynamics can be widely applied to any type of material or process for which temperature is well-defined.  However, this also generally precludes consideration of very small systems.  To remedy this, more than forty years ago Terrell L. Hill, then at the University of Oregon, developed an approach extending thermodynamics to “small scales” such as characterized by colloid particles, surfactant micelles, protein molecules and similar structures.  This field languished in the intervening decades, but now such structures are recognized as falling under the general rubric of “nanotechnology”.  In this talk, Hill’s methods will be discussed and extended and some representative systems described.  It is hoped that this will motivate further development of nanoscale thermodynamics and its practical application to technology