Title: Antisymmetry: Fundamentals and Applications

Abstract: Symmetry is fundamental to understanding our physical world.  An antisymmetry operation switches between two different states of a trait, such as two time-states, position-states, charge-states, spin-states, chemical-species etc.   This talk will cover the fundamental concept of antisymmetry, with brief mentions of two well-established antisymmetries, namely spatial inversion in point groups and time reversal. Then it will introduce two new ones, namely, distortion reversal and wedge reversion.  The distinction between classical and quantum mechanical descriptions of time reversal will be discussed.  Applications of these antisymmetries will be presented such as crystallography, property tensors, transition state theory, magnetic structures, ferroelectric and multiferroic switching, and classifying physical quantities in arbitrary dimensions.Brief Bio:  Gopalan received his PhD in Materials science and Engineering at Cornell University in 1995.  After a brief stint as a postdoctoral scholar in the electrical and Computer Engineering at the Carnegie Mellon University, he joined Los Alamos National Labs as Director-funded Postodctoral fellow.  In 1999, he joined Pennsylvania State University as a tenure-track assistant professor, and became a full professor in 2008.  His interests are in symmetry, quantum materials, nonlinear optical imaging and spectroscopy, diffraction techniques, and optical device applications. He is the recipient of the NSF Career award, Robert R. Coble award and Richard M. Fulrath award both from the American Ceramics Society, and the Faculty Scholar Medal from the Pennsylvania State University.  He is a Fellow of the American Physical Society.