Homotopy theoretic models of identity types

This paper presents a novel connection between homotopical algebra and mathematical logic. It is shown that a form of intensional type theory is valid in any Quillen model category, generalizing the Hofmann-Streicher groupoid model of Martin-Loef type theory.Comment: 11 page

Growing a Green Economy for All: From Green Jobs to Green Ownership

This Democracy Collaborative report provides the first comprehensive survey of community wealth building institutions in the green economy. Featuring ten cases, the report identifies how policy and philanthropy can build on these examples to create "green jobs you can own.

Constraints on dark and visible mass in galaxies from strong gravitational lensing

We give a non-exhaustive review of the use of strong gravitational lensing in placing constraints on the quantity of dark and visible mass in galaxies. We discuss development of the methodology and summarise some recent results.Comment: To appear in proceedings of IAU Symposium 244, 'Dark Galaxies and Lost Baryons', 25th - 29th June 2007. Nine pages, five figures. Version 2 updates bibliograph

DAIRY FARMS IN MICHIGAN'S U.P., 2001

Livestock Production/Industries,

Reviews

Teaching and Learning Materials and the Internet by Ian Forsyth, London: Kogan Page, 1996. ISBN: 0–7494‐ 20596. 181 pages, paperback. £18.99