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arXiv · hep-th/0110079

Higher Derivative Gravity and Torsion from the Geometry of C-spaces

Abstract

We start from a new theory (discussed earlier) in which the arena for physics is not spacetime, but its straightforward extension-the so called Clifford space ($C$-space), a manifold of points, lines, areas, etc..; physical quantities are Clifford algebra valued objects, called polyvectors. This provides a natural framework for description of supersymmetry, since spinors are just left or right minimal ideals of Clifford algebra. The geometry of curved $C$-space is investigated. It is shown that the curvature in $C$-space contains higher orders of the curvature in the underlying ordinary space. A $C$-space is parametrized not only by 1-vector coordinates $x^μ$ but also by the 2-vector coordinates $σ^{μν}$, 3-vector coordinates $σ^{μνρ}$, etc., called also {\it holographic coordinates}, since they describe the holographic projections of 1-lines, 2-loops, 3-loops, etc., onto the coordinate planes. A remarkable relation between the "area" derivative $\p/ \p σ^{μν}$ and the curvature and torsion is found: if a scalar valued quantity depends on the coordinates $σ^{μν}$ this indicates the presence of torsion, and if a vector valued quantity depends so, this implies non vanishing curvature. We argue that such a deeper understanding of the $C$-space geometry is a prerequisite for a further development of this new theory which in our opinion will lead us towards a natural and elegant formulation of $M$-theory.

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BibTeXRIS

C. Castro, M. Pavsic. 2002-04-27. Higher Derivative Gravity and Torsion from the Geometry of C-spaces. https://doi.org/10.1016/s0370-2693(02)02068-3

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