The Effective Lorentzian and Teleparallel Spacetimes Generated by a Free Electromagnetic Field

In this paper we show that a free electromagnetic field living in Minkowski spacetime generates an effective Weitzenbock or an effective Lorentzian spacetime whose properties aredetermined in details. These results are possible because we found using the Clifford bundle formalism the noticeable result that the energy-momentum densities of a free electromagnetic field are sources of the Hodge duals of exact 2-form fields which satisfy Maxwell like equations.Comment: A missing term in Eq.(14) has been inserted and some misprints correcte

A Maxwell Like Formulation of Gravitational Theory in Minkowski Spacetime

In this paper using the Clifford bundle formalism a Lagrangian theory of the Yang-Mills type (with a gauge fixing term and an auto interacting term) for the gravitational field in Minkowski spacetime is presented. It is shown how two simple hypothesis permit the interpretation of the formalism in terms of effective Lorentzian or teleparallel geometries. In the case of a Lorentzian geometry interpretation of the theory the field equations are shown to be equivalent to Einstein's equations.Comment: This is a version of a paper published in Int. J. Mod. Phs. D 16(6), 1027-1041 (2007) where some misprints and typos have been corrected, some references have been updated, a footnote has been added and some few sentences have been rewritten to better explain the role of the (plastic) deformation tensor

Mapping and valuing habitat services: two applications at local scale

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