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Register a new userA gauge invariant prescription to avoid $gamma$-crossing instability in Galileon bounce
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Added by
Rathul Nath Raveendran
Publication date
2019
fields
Physics
and research's language is
English
Authors
Rathul Nath Raveendran
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We revisit the evolutions of scalar perturbations in a non-singular Galileon bounce. It is known that the second order differential equation governing the perturbations is numerically unstable at a point called $gamma$-crossing. This instability is usually circumvented using certain gauge choices. We show that the perturbations can be evolved across this point by solving the first order differential equations governing suitable gauge invariant quantities without any instabilities. We demonstrate this method in a matter bounce scenario described by the Galileon action.
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