4 papers
Cosmic topology. Part Ic. Limits on lens spaces from circle searches
Samanta Saha, Craig J. Copi, Glenn D. Starkman +11
Cosmic microwave background (CMB) temperature and polarization observations indicate that in the best-fit Cold Dark Matter model of the Universe, the local geometry is consist…
Cosmic topology. Part I. Limits on orientable Euclidean manifolds from circle searches
Pip Petersen, Yashar Akrami, Craig J. Copi +9
The Einstein field equations of general relativity constrain the local curvature at every point in spacetime, but say nothing about the global topology of the Universe. Cosmic micr…
Cosmic topology. Part IVa. Classification of manifolds using machine learning: a case study with small toroidal universes
Andrius Tamosiunas, Fernando Cornet-Gomez, Yashar Akrami +16
Non-trivial spatial topology of the Universe may give rise to potentially measurable signatures in the cosmic microwave background. We explore different machine learning approaches…
Cosmic topology. Part IIa. Eigenmodes, correlation matrices, and detectability of orientable Euclidean manifolds
Johannes R. Eskilt, Yashar Akrami, Stefano Anselmi +11
If the Universe has non-trivial spatial topology, observables depend on both the parameters of the spatial manifold and the position and orientation of the observer. In infinite Eu…