Max Dehn, Axel Thue, and the Undecidable

This is a short essay on the roles of Max Dehn and Axel Thue in the formulation of the word problem for (semi)groups, and the story of the proofs showing that the word problem is undecidable.Comment: Definition of undecidability and unsolvability improve

New directions in Nielsen-Reidemeister theory

The purpose of this expository paper is to present new directions in the classical Nielsen-Reidemeister fixed point theory. We describe twisted Burnside-Frobenius theorem, groups with $R_\infty$ \emph{property} and a connection between Nielsen fixed point theory and symplectic Floer homology.Comment: 50 pages, surve

Seidel's long exact sequence on Calabi-Yau manifolds

In this paper, we generalize construction of Seidel's long exact sequence of Lagrangian Floer cohomology to that of compact Lagrangian submanifolds with vanishing Malsov class on general Calabi-Yau manifolds. We use the framework of anchored Lagrangian submanifolds developed in \cite{fooo:anchor} and some compactness theorem of \emph{smooth} $J$-holomorphic sections of Lefschetz Hamiltonian fibration for a generic choice of $J$. The proof of the latter compactness theorem involves a study of proper pseudoholomorphic curves in the setting of noncompact symplectic manifolds with cylindrical ends.Comment: 59 pages, comments welcom

A Gift Of Knowing: The Art Of Dorothea Rockburne

Published for the exhibition A Gift of Knowing: The Art of Dorothea Rockburne at the Bowdoin College Museum of Art from March 14 through April 26, 2015, supported by the Elizabeth B. G. Hamlin Fund and the Shapell Family Art Fund. Design by Wilcox Design, Cambridge, Massachusetts Copyright© 2015 Bowdoin Collegehttps://digitalcommons.bowdoin.edu/art-museum-exhibition-catalogs/1099/thumbnail.jp