# Hyperbolic Methods for Einstein’s Equations

**Oscar A. Reula
**

Universidad Nacional de Córdoba, FaMAF

Ciudad Universitaria

5000 Córdoba, Argentina

http://www.famaf.unc.edu.ar/~reula/

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Abstract

I review evolutionary aspects of general relativity, in particular those related to the
hyperbolic character of the field equations and to the applications or consequences that this
property entails. I look at several approaches to obtaining symmetric hyperbolic systems of
equations out of Einstein’s equations by either removing some gauge freedoms from them, or
by considering certain linear combinations of a subset of them.