Title: Wave driven inundation for reef fringed atolls
Speaker: Prof. Janet M. Becker, Department of Geology and Geophysics
Abstract: As sea level rises, the threat of wave driven inundation for low lying atolls is anticipated to increase. Wave driven inundation results from three dynamically distinct components: sea and swell energy, breaking wave setup, and low frequency (infragravity) energy. Here, results from field experiments in Ipan, Guam and Majuro and Roi-Namur, RMI are presented that demonstrate the importance of low frequency energy on fringing reefs. The observations are described in terms of linear and nonlinear dynamics. Projections of wave driven inundation that include all components for Roi-Namur under future sea level scenarios are presented.
Speaker: Kostas Beros (U. North Texas)
Title: Normal numbers and a completeness result in the difference hierarchy
Abstract: In this talk I consider a natural set of real numbers, arising in ergodic theory, and show that it is Wadge-complete for the class of differences of $F_{\sigma\delta}$ sets. I will recall basic definitions and motivate my result with a discussion of related theorems from the past twenty years.
Logic seminar
Keller Hall 401
Title: A brief overview of topological data analysis
Achilles Beros will
speak on “Algorithmic learning and the arithmetic hierarchy”
Summary:
I will present a theorem from my thesis that establishes the arithmetic
complexity of a well-known learning criterion. Two other papers have
been published since then that continue the line of research. I will
discuss the newer papers as well as broader connections between
recursion theory and learning theory.
Keller Hall 303
This week the Sporadic Logic Seminar will be Mushfeq Khan speaking on
“Turing degrees and Muchnik degrees of recursively
bounded DNR functions”.
Summary:
This talk is based on a forthcoming paper by Steve Simpson. It contains
some results that shed light on a part of the Muchnik lattice that remains
poorly understood: the various degrees of recursively bounded DNR functions
obtained by varying the recursive bound.
Keller 303