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تسجيل مستخدم جديدNew Cosmological Solutions in Massive Gravity
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We find new, simple cosmological solutions with flat, open, and closed spatial geometries, contrary to the previous wisdom that only the open model is allowed. The metric and the St{u}ckelberg fields are given explicitly, showing nontrivial configurations of the St{u}ckelberg in the usual Friedmann-Lema^{i}tre-Robertson-Walker coordinates. The solutions exhibit self-acceleration, while being free from ghost instabilities. Our solutions can accommodate inhomogeneous dust collapse represented by the Lema^{i}tre-Tolman-Bondi metric as well. Thus, our results can be used not only to describe homogeneous and isotropic cosmology but also to study gravitational collapse in massive gravity.
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