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arXiv · 1606.05747

Complete Hamiltonian analysis of cosmological perturbations at all orders II: Non-canonical scalar field

Debottam Nandi·S. Shankaranarayanan
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Abstract

In this work, we present a consistent Hamiltonian analysis of cosmological perturbations for generalized non-canonical scalar fields. In order to do so, we introduce a new phase-space variable that is uniquely defined for different non-canonical scalar fields. We also show that this is the simplest and efficient way of expressing the Hamiltonian. We extend the Hamiltonian approach of [arXiv:1512.02539] to non-canonical scalar field and obtain a new definition of speed of sound in phase-space. In order to invert generalized phase-space Hamilton's equations to Euler-Lagrange equations of motion, we prescribe a general inversion formulae and show that our approach for non-canonical scalar field is consistent. We also obtain the third and fourth order interaction Hamiltonian for generalized non-canonical scalar fields and briefly discuss the extension of our method to generalized Galilean scalar fields.

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Debottam Nandi, S. Shankaranarayanan. 2016-06-18. Complete Hamiltonian analysis of cosmological perturbations at all orders II: Non-canonical scalar field. https://doi.org/10.1088/1475-7516%2F2016%2F10%2F008

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