Events

<<	March 2026	>>

<< Fall 2025	Spring 2026	Summer 2026 >>
Subscribe your calendar or receive email announcements of events

Events on Thursday, March 12th, 2026: R. G. Herb Condensed Matter Seminar; Only the ambidextrous can flock: chirality destroys order in polar active matter; Time: 10:00 am - 11:00 am; Place: 5310 Chamberlin Hall; Speaker: John Toner, University of Oregon; Abstract: I'll show that flocks of chiral living creatures (i.e., organisms that are right or left handed) moving on a surface, composed of critters can not form a long range ordered flocking state (i.e., a state in which the spatially averaged velocity vector is non-zero,) even though it is well-known that they can order in this way if they are achiral. "Immortal" flocks (flocks in which the creatures are not being born and dying on the time scales iof interest) prove to be much more nearly ordered than "Malthusian" flocks in which birth and death do occur. Immortal flocks have a phase which, although not truly long-range ordered, better ordered than the "Kosterlitz-Thouless quasi-long-range ordered phase" (KT phase) of the equilibrium 2d XY model. This phase exhibits non-unversal exponents of a type very different from the familiar non-universal exponents of the KT phase.; Host: Alex Levchenko; Add this event to your calendar