# Hyperbolic universes with a horned topology and the cosmic microwave background anisotropy

@article{Aurich2004HyperbolicUW, title={Hyperbolic universes with a horned topology and the cosmic microwave background anisotropy}, author={Ralf Aurich and Sven Lustig and Frank Steiner and Holger Then}, journal={Classical and Quantum Gravity}, year={2004}, volume={21}, pages={4901-4925} }

We analyse the anisotropy of the cosmic microwave background (CMB) in hyperbolic universes possessing a non-trivial topology with a fundamental cell having an infinitely long horn. The aim of this paper is twofold. On the one hand, we show that the horned topology does not lead to a flat spot in the CMB sky maps in the direction of the horn as stated in the literature. On the other, we demonstrate that a horned topology having a finite volume could explain the suppression of the lower…

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