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arXiv · 2504.16313

Non-geometrical perturbation on homogeneous stealth dust

José Blanco·Cuauhtemoc Campuzano·J. C. Corona-Oran·Víctor H. Cárdenas
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Abstract

In this work, we study a non-geometrical perturbation to the stealth field, which means the background remains invariant. The stealh is homogeneous in a universe whose source is dust and demand that perturbation unchanged density. As a regular procedure, we introduce a parameter $\lambda$ to perturb the scalar field equation and get an intriguing expression of the equation, similar to a series expansion in $\lambda$. From this procedure, we distinguish and approach to discriminate solutions, and the numerical solutions show that the most significant contribution to the solution comes from the linear term of $\lambda$.

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José Blanco, Cuauhtemoc Campuzano, J. C. Corona-Oran, Víctor H. Cárdenas. 2025-04-22. Non-geometrical perturbation on homogeneous stealth dust. https://arxiv.org/abs/2504.16313

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