164 citations · 770 across the 24 of their papers we have counts for
12 papers · 1 filter
Beyond the Kullback--Leibler divergence: the likelihood-ratio distribution as a detectability measure
Amirhossein Samandar, Mikel Martin Barandiaran, Linn Htat Lu +13
The Kullback--Leibler (KL) divergence is the expectation value of the log-likelihood ratio between two specified models, evaluated with respect to one of the two models. It provide…
Cosmic topology. Part Va. Information content of the observable Universe
Deyan P. Mihaylov, Mikel Martin Barandiaran, Stefano Anselmi +14
If the Universe possesses a compact spatial topology with characteristic scale not much larger than the diameter of the observable Universe, then the associated symmetry transforma…
The Topology of the Universe
Craig J. Copi, Deyan P. Mihaylov, Anna Negro +14
Is the Universe infinite in all directions? The only way to know is to look. A non-trivial cosmic topology would imprint subtle signatures on the cosmic microwave background (CMB)…
Cosmic topology. Part IIc. Detectability with non-standard primordial power spectrum
Joline Noltmann, Andrius Tamosiunas, Deyan P. Mihaylov +13
Non-trivial spatial topology of the Universe can imprint potentially observable signatures on the cosmic microwave background (CMB). In this study, we investigate how deviations fr…
Cosmic topology. Part IIb. Eigenmodes, correlation matrices, and detectability of non-orientable Euclidean manifolds
Craig J. Copi, Amirhossein Samandar, Glenn D. Starkman +13
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…
Cosmic topology. Part IIIb. Eigenmodes and correlation matrices of spin-2 perturbations in orientable Euclidean manifolds
Amirhossein Samandar, Javier Carrón Duque, Craig J. Copi +13
We study the eigenmodes of the spin-2 Laplacian in orientable Euclidean manifolds and their implications for the tensor-induced part of the cosmic microwave background (CMB) temper…
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 consiste…
Cosmic topology. Part IIIa. Microwave background parity violation without parity-violating microphysics
Amirhossein Samandar, Javier Carrón Duque, Craig J. Copi +11
The standard cosmological model, which assumes statistical isotropy and parity invariance, predicts the absence of correlations between even-parity and odd-parity observables of th…
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…
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…
Promise of Future Searches for Cosmic Topology
Yashar Akrami, Stefano Anselmi, Craig J. Copi +12
The shortest distance around the Universe through us is unlikely to be much larger than the horizon diameter if microwave background anomalies are due to cosmic topology. We show t…