8 papers
A First Observational Assessment of Cosmic Backreaction Over an Extended Redshift Range
S. M. Koksbang
In the recent preprint arXiv:2604.07244v1, the authors introduce a novel combination of redshift, distance, and expansion rate observables for constraining cosmic backreaction obse…
Model-independent constraints on generalized FLRW consistency relations with bootstrap-based symbolic regression
S. M. Koksbang, A. Heinesen
The standard CDM cosmological model faces increasing tensions between key observations, motivating tests that probe its underlying assumptions. In a companion letter, we presen…
Diagnostic Consistency Tests of the Concordance Cosmology
S. M. Koksbang, A. Heinesen
The CDM cosmological model faces increasingly significant and robust tensions among independent cosmological probes, prompting renewed scrutiny of its foundational assumptions.…
Transverse Velocities in Real-Time Cosmology: Position Drift in Relativistic N-Body Simulations
Alexander Oestreicher, Chris Clarkson, Julian Adamek +1
The era of real-time cosmology has begun. It is now possible to directly measure the apparent drift of high-redshift astronomical sources across the sky . Th…
Redshift Drift in Relativistic N-Body Simulations
Alexander Oestreicher, Chris Clarkson, Julian Adamek +1
The cosmological redshift drift promises to be the first observable directly measuring the evolution of the cosmic expansion rate and should be detectable with upcoming surveys by…
Testing inhomogeneous cosmography in our cosmic neighborhood using CosmicFlows-4
S. M. Koksbang
The convergence of the third order general cosmographic expansion of the luminosity distance is examined using several versions of a semi-realistic model of our local cosmic neighb…