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arXiv · 1309.4282

Note on the thermodynamics and the speed of sound of a scalar field

Oliver F. Piattella·Júlio C. Fabris·Neven Bilić
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Abstract

We investigate the correspondence between a perfect fluid and a scalar field and show a possible way of expressing thermodynamic quantities such as entropy, particle number density, temperature and chemical potential in terms of the scalar field phi and its kinetic term X. We prove a theorem which relates isentropy with purely kinetic Lagrangian. As an application, we study the evolution of the gravitational potential in cosmological perturbation theory.

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Oliver F. Piattella, Júlio C. Fabris, Neven Bilić. 2013-09-17. Note on the thermodynamics and the speed of sound of a scalar field. https://doi.org/10.1088/0264-9381/31/5/055006

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