The Kansan Glaciation in Southeastern Indiana

Author Institution: Earlham College, Richmond, IndianaBuried Kansan drift and Yarmouth soil beneath Illinoian drift are described from three locations south of the Wisconsin drift border in southeastern Indiana. The occurrence in Kansan drift of bright red, clayey, non-calcareous, limestone-derived soil inclusions, and abundant residual chert cobbles from the local Silurian Laurel Limestone suggest that the Kansan ice may have been the first to reach this area. The scattered upland erratics in northern Kentucky, therefore, seem more certainly to be Kansan in age, as suggested originally by Leverett. The Townsend Farm section provides a basis for geologic-climate subdivisions of the Kansan Stage in southeastern Indiana, named as follows: Kansan Stage Columbia Stade Garrison Creek Interstade Alpine Stade The slightly greater depth of leaching of the Yarmouth soil in the Townsend Farm section as compared to depths in similar buried Sangamon soils in southeastern Indiana suggests that the Yarmouth interglacial interval was slightly longer than the Sangamon interglacial interval in this area

Computer modeling of the mineralogy of the Martian surface, as modified by aqueous alteration

Mineralogical constraints can be placed on the Martian surface by assuming chemical equilibria among the surface rocks, atmosphere and hypothesized percolating groundwater. A study was made of possible Martian surface mineralogy, as modified by the action of aqueous alteration, using the EQ3/6 computer codes. These codes calculate gas fugacities, aqueous speciation, ionic strength, pH, Eh and concentration and degree of mineral saturation for complex aqueous systems. Thus, these codes are also able to consider mineralogical solid solutions. These codes are able to predict the likely alteration phases which will occur as the result of weathering on the Martian surface. Knowledge of the stability conditions of these phases will then assist in the definition of the specifications for the sample canister of the proposed Martian sample return mission. The model and its results are discussed

Spectral Properties of the Attractive Hubbard Model

Deviations from Fermi liquid behavior are well documented in the normal state of the cuprate superconductors, and some of these differences are possibly related to pre-formed pairs appearing at temperatures above T_c. In order to test these ideas we have investigated the attractive Hubbard model within a self-consistent, conserving ladder approximation. In this version of the theory, no feature is present which can be related to the pseudo gap found in the high-T_c materials. Further, the interactions between two-particle bound states change the physics of the superconducting instability in a profound fashion, and lead to a completely different phenomenology that one predicts based on the non-self-consistent version of the same theory.Comment: 4 pages including 2 figures, to appear in the proceedings of the SNS'9

Application of a multi-site mean-field theory to the disordered Bose-Hubbard model

We present a multi-site formulation of mean-field theory applied to the disordered Bose-Hubbard model. In this approach the lattice is partitioned into clusters, each isolated cluster being treated exactly, with inter-cluster hopping being treated approximately. The theory allows for the possibility of a different superfluid order parameter at every site in the lattice, such as what has been used in previously published site-decoupled mean-field theories, but a multi-site formulation also allows for the inclusion of spatial correlations allowing us, e.g., to calculate the correlation length (over the length scale of each cluster). We present our numerical results for a two-dimensional system. This theory is shown to produce a phase diagram in which the stability of the Mott insulator phase is larger than that predicted by site-decoupled single-site mean-field theory. Two different methods are given for the identification of the Bose glass-to-superfluid transition, one an approximation based on the behaviour of the condensate fraction, and one of which relies on obtaining the spatial variation of the order parameter correlation. The relation of our results to a recent proposal that both transitions are non self-averaging is discussed.Comment: Accepted for publication in Physical Review

Ecological Significance of a Drifting Object to Pelagic Fishes

Volume: 21Start Page: 486End Page: 49

The myth of the new: Mass digitization, distant reading, and the future of the book

This article presents the theoretical background to a wider project that is attempting to increase our understanding of the impact and uses of large-scale digitization, being undertaken by the first author at University College London with the working title ‘What is the impact of large-scale digitization upon researchers and the information sector?’ It discusses the controversy surrounding the emergence of mass digitization: the creation and collection of huge resources containing millions of pages of textual cultural content. It demonstrates that the polarized nature of the literature about this technological development is far from unprecedented, and in fact can be traced through the theory of a number of varied fields: the debate surrounding mechanization and digital technologies, our understanding of the role of the sublime in modern representations of technology, the similarities between the sociology of city life and digital information overload, and the way in which innovations are diffused throughout society. It proposes that these theories explain why debates around technological innovation often become so hyperbolic, creating an almost mythological view of technological determination. It concludes that, as a result of the processes outlined in this theory, mass digitization has become stuck between two conflicting rhetorical movements, and that it is therefore necessary to begin working to increase our understanding of this technology and to move the debate onwards using evidence from the real world