40 citations · 282 across the 19 of their papers we have counts for
21 papers
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…
Breaking de Sitter Symmetry with Cosmic Topology: Cosmological Role of Infrared Vacuum Freedom
Anna Negro, Kurt Hinterbichler, Glenn D. Starkman +5
When spatial sections of spacetime are topologically nontrivial, the symmetry arguments usually used to choose the Bunch-Davies vacuum are no longer guaranteed to apply. We study t…
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…
Quantum Signatures of Cosmic Topology: How Casimir Backreaction Transmits Isotropy Violation
Anna Negro, Kurt Hinterbichler, Glenn D. Starkman +17
A finite, scheme-independent Casimir contribution to the stress-energy tensor arises naturally for quantum fields in universes with non-trivial spatial topology. We compute this Ca…
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 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…
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…
What is flat ΛCDM, and may we choose it?
Stefano Anselmi, Matthew F. Carney, John T. Giblin +5
The Universe is neither homogeneous nor isotropic, but it is close enough that we can reasonably approximate it as such on suitably large scales. The inflationary--Cold Dark Mat…
Cosmological forecasts for future galaxy surveys with the linear point standard ruler: Toward consistent BAO analyses far from a fiducial cosmology
Stefano Anselmi, Glenn D. Starkman, Alessandro Renzi
The linear point (LP) standard ruler was identified as the basis of a purely geometric method for exploiting the Baryon Acoustic Oscillations (BAO). The LP exploits the BAO feature…
On the question of measuring spatial curvature in an inhomogeneous universe
Chi Tian, Stefano Anselmi, Matthew F. Carney +3
The curvature of a spacetime, either in a topological sense, or averaged over super-horizon-sized patches, is often equated with the global curvature term that appears in Friedmann…
Linear Point and Sound Horizon as Purely Geometric standard rulers
Márcio O'Dwyer, Stefano Anselmi, Glenn D. Starkman +3
The Baryon Acoustic Oscillations feature (BAO) imprinted in the clustering correlation function is known to furnish us cosmic distance determinations that are independent of the co…
Cosmic distance inference from purely geometric BAO methods: Linear Point standard ruler and Correlation Function Model Fitting
Stefano Anselmi, Pier-Stefano Corasaniti, Ariel G. Sanchez +3
Leveraging the Baryon Acoustic Oscillations (BAO) feature present in clustering 2-point statistics, we aim to measure cosmological distances independently of the underlying backgro…
The Linear Point Standard Ruler for galaxy survey data: validation with mock catalogues
Stefano Anselmi, Pier-Stefano Corasaniti, Glenn D. Starkman +2
Due to late time non-linearities, the location of the acoustic peak in the two-point galaxy correlation function is a redshift-dependent quantity, thus it cannot be simply employed…
Failures of homogeneous and isotropic cosmologies in Extended Quasi-Dilaton Massive Gravity
Stefano Anselmi, Saurabh Kumar, Diana López Nacir +1
We analyze the Extended Quasi-Dilaton Massive Gravity model around a Friedmann-Lemaître-Robertson-Walker cosmological background. We present a careful stability analysis of asympto…
The Linear Point: A cleaner cosmological standard ruler
Stefano Anselmi, Glenn D. Starkman, Pier-Stefano Corasaniti +2
We show how a characteristic length scale imprinted in the galaxy two-point correlation function, dubbed the "linear point", can serve as a comoving cosmological standard ruler. In…
Beating non-linearities: improving the Baryon Acoustic Oscillations with the linear point
Stefano Anselmi, Glenn D. Starkman, Ravi K. Sheth
We propose a new way of looking at the Baryon Acoustic Oscillations in the Large Scale Structure clustering correlation function. We identify a scale s_LP that has two fundamental…
Extreme parameter sensitivity in quasidilaton massive gravity
Stefano Anselmi, Diana López Nacir, Glenn D. Starkman
We reanalyze the behavior of Friedmann-Lemaître-Robertson-Walker cosmologies in the recently proposed quasidilaton massive-gravity model, and discover that the background dynamics…