Gravitational backreaction on a cosmic string: Formalism

Understand

We develop a method for computing the linearized gravitational backreaction for Nambu-Goto strings using a fully covariant formalism.

• We work with equations of motion expressed in terms of a higher dimensional analog of the geodesic equation subject to self-generated forcing terms.
• The approach allows arbitrary spacetime and worldsheet gauge choices for the background and perturbation.
• The perturbed spacetime metric may be expressed as an integral over a distributional stress-energy tensor supported on the string worldsheet.