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arXiv · 2606.31472

The unavoidable de Sitter fate of a scale-invariant Universe

Chiara Cecchini·Massimiliano Rinaldi
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Abstract

We consider a very general scale-invariant scalar-tensor theory of gravity and its flat cosmological solutions. We show that any stable configuration with non-degenerate gravitational dynamics carries a non-vanishing cosmological constant, unless the quartic self-coupling of the scalar field vanishes. Since this condition is not protected against radiative corrections, a residual cosmological constant is expected as a generic and robust prediction of this class of theories. This result suggests that dark energy may be a natural consequence of an early scale-invariant phase of the Universe.

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Chiara Cecchini, Massimiliano Rinaldi. 2026-06-30. The unavoidable de Sitter fate of a scale-invariant Universe. https://arxiv.org/abs/2606.31472

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