Physics Colloquia

Fall 2016 (usually Fridays 2:00 PM in SE 319)

Date Speaker Title
Oct 14 Stefan Kautsch Unified aspects of topological phases via anyon condensation
Nov 18 Andrew Johnson  An Empiricist’s Dream: From Cortical Circuits to Behavior
Jan 27 Maurizio Giannotti  Astrophysical Anomalies and Axions: the physics potential of the International Axion Observatory


Colloquium Abstracts

The Mystery of Superthin Galaxies – Too thin or too beautiful?

Stefan Kautsch (Nova Southeastern University), Oct 14

Superthin galaxies are slowly star-forming disk galaxies with very thin and low-density stellar disks. It is unknown how these objects survived the violent merging history of the universe. Their dark-matter halos could provide some answers. Thus, I present new observations which may help to establish them as a diverse class of extragalactic objects.


An Empiricist’s Dream: From Cortical Circuits to Behavior

Andrew Johnson (MPI Florida), Nov 18

After a brief pedagogical introduction, I will give an overview of research performed in the department of digital neuroanatomy at the Max Planck Florida Institute (MPFI).  The work centers on trying to understand how sensory input is transformed into decision making.  Over the last decade or more, electrophysiological recording and imaging of single neurons during sensory-motor tasks has identified the neural substrates of sensation and action in various cortical areas.  Still the crucial questions of 1) how these correlates are implemented within the underlying neural networks and 2) how their output triggers decisions, can only be answered when individual functional measurements are integrated into a coherent model of all task-related circuits.  Our goal is to use the rodent vibrissal system for building such a model in the context of how a tactile-mediated percept is encoded by the interplay between biophysical, cellular and network mechanisms.  Using a multidisciplinary approach, combining in-vivo electrophysiology, virus injections, custom imaging/reconstruction tools and Monte Carlo simulations, our reverse engineering strategy provides mechanistic insight into perceptual decision making and functions as a showcase—generalizable across sensory modalities and species—of how to derive computations that underlie behavior.


Astrophysical Anomalies and Axions: the physics potential of the International Axion Observatory

Maurizio Giannotti (Barry U.), Jan 27

I will give an update on the anomalies observed in the cooling of several stellar systems and on the interpretation in terms of axions and axion like particles (ALPs). I will show that the relevant region in the axion and ALP parameter space hinted by these anomalies can be probed by the next generation of axion detectors, in particular by the International Axion Observatory (IAXO).