https://doi.org/10.1140/epjc/s10052-025-15268-6
Regular Article - Theoretical Physics
Taming singularities and chaos in conformal gravity
1
Center for Astronomy and Astrophysics, Center for Field Theory and Particle Physics, and Department of Physics, Fudan University, 200438, Shanghai, China
2
Dipartimento di Fisica, Universitá di Cagliari, Cittadella Universitaria, 09042, Monserrato, Italy
3
INFN, Sezione di Cagliari, Cittadella Universitaria, 09042, Monserrato, Italy
4
School of Humanities and Natural Sciences, New Uzbekistan University, 100001, Tashkent, Uzbekistan
a
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Received:
4
November
2025
Accepted:
23
December
2025
Published online:
20
January
2026
Abstract
We hereby address the cosmological singularity problem in a general gravitational theory invariant under Weyl conformal transformations. In particular, we focus on the Bianchi IX spacetime and we show that both the initial (big bang) and final (big crunch) singularities disappear in an infinite class of conformal frames naturally selected according to analyticity. It turns out that the past and future singularities are both unattainable within a finite affine parameter (for massless particles) or within a finite proper time (for massive and conformally coupled particles). In order to prove such a statement, we show the geodesic completion of the spacetime when probed by massless, massive, and conformally coupled particles. Finally, the chaotic behavior of the spacetime near the singularity is tamed by a conformal rescaling that turns the Bianchi IX metric into a quasi-FLRW spacetime.
© The Author(s) 2026
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