Study of some orthosymplectic Springer fibers

We decompose the fibers of the Springer resolution for the odd nilcone of the Lie superalgebra \osp(2n+1,2n) into locally closed subsets. We use this decomposition to prove that almost all fibers are connected. However, in contrast with the classical Springer fibers, we prove that the fibers can be disconnected and non equidimensional

Results of the first two seasons of underwater surveys at Episkopi Bay and Akrotiri, Cyprus

During the summers of 2003 and 2004, a small team of graduate students initiated an underwater archaeological survey off the coast of Cyprus as part of the University of Cincinnati excavations at Episkopi-Bamboula. With the support of the Institute of Nautical Archaeology (INA) at Texas A&M University and RPM Nautical Foundation, the project explored the seabed south and west of the Akrotiri Peninsula at Episkopi Bay. The overall aim of this ongoing diachronic survey is to determine the extent and nature of maritime contacts at Episkopi-Bamboula and its Greco-Roman successor, Kourion, from the Bronze Age through the Byzantine period. Efforts during these first two seasons concentrated on simple visual inspection of several promising areas near dangerous cliffs, offshore rocks and shallow reefs, as well as potential harbors and anchorages. The team recorded substantial pottery and anchor assemblages at Dreamer?s Bay, Cape Zevgari, and Avdimou Bay, including at least three shipwreck sites. Throughout the area, amphoras and anchors attest to varying levels of maritime activity over the past three millennia.The underwater material record reveals a modest level of Classical trade, followed by a respectable increase during the Hellenistic era. While very little material thus far can be attributed to the earlier Imperial centuries, the greatest quantities in terms of both individual sherds and coherent assemblages speaks strongly to intense trade during the Late Roman (Early Byzantine) period, from the fourth through the seventh century. Not surprisingly, this rapid floruit in maritime trade parallels the expansion of settlement throughout the island, including its eventual collapse in the middle of the seventh century

Cônes nilpotents des super algèbres de Lie orthosymplectiques

International audienceWe look at the odd nilpotent orbits of osp(2n+1,2n), giving a combinatorial interpretation which enables us, via the square map, to explain the link with even nilpotent orbits. We then study the closure ordering of the odd nilpotent orbits. Finally, we give a desingularization of the odd nilpotent cone

Ephemeral Heritage: Boats, Migration, and the Central Mediterranean Passage

The central Mediterranean today marks one of the most active and dangerous routes for sea crossings to Europe, due in no small part to border regimes designed to prevent the mobilities that have defined these waters from earliest antiquity. This article considers initial results of fieldwork undertaken to document and make visible the material culture of contemporary vessels used to carry forced and undocumented migrants to southeast Sicily over the past decade. These former fishing craft reveal structural and spatial adaptations to facilitate a different traffic, reflected also in items left behind when the boats were intercepted. Archaeology helps to embed these journeys within long-term frameworks of connectivity and to situate their ephemeral traces alongside more traditional notions of Mediterranean maritime heritage. In a region that celebrates its deep connections to the sea, care for the materiality of these contemporary mobilities foregrounds human experiences, while serving goals of advocacy, empowerment, and social justice amid global change

Similarity reduction of the modified Yajima-Oikawa equation

We study a similarity reduction of the modified Yajima-Oikawa hierarchy. The hierarchy is associated with a non-standard Heisenberg subalgebra in the affine Lie algebra of type A_2^{(1)}. The system of equations for self-similar solutions is presented as a Hamiltonian system of degree of freedom two, and admits a group of B\"acklund transformations isomorphic to the affine Weyl group of type A_2^{(1)}. We show that the system is equivalent to a two-parameter family of the fifth Painlev\'e equation.Comment: latex2e file, 18 pages, no figures; (v2)Introduction is modified. Some typos are correcte