S. F. Gull, A. N. Lasenby and C. J. L. Doran
Geometric algebra, spacetime physics and gravitation.
In O. Lahav, E. Terlevich and R. J. Terlevich, editors, Gravitational Dynamics, (Cambridge University Press, 1996), pp. 171-180.

Abstract: Clifford's ` geometric algebra' is presented as the natural language for expressing geometrical ideas in mathematical physics. Its spacetime version `spacetime algebra' is introduced and is shown to provide a powerful, invariant description of relativistic physics. Applications to electromagnetism and gravitation are discussed.

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