220 citations · 1.2k across the 39 of their papers we have counts for
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Cosmological zoom-in perturbation theory as a consistent beyond point-particle approximation framework
Obinna Umeh
Modelling structure formation across the full dynamical range of the Universe remains a major challenge in cosmology. This difficulty originates from a fundamental limitation of ge…
An essential building block for cosmological zoom-in perturbation theory
Obinna Umeh
The evolution of large-scale structure within the standard model of cosmology is well posed only up to the onset of shell crossing, where particle trajectories appear to intersect.…
The HI intensity mapping power spectrum: insights from recent measurements
Hamsa Padmanabhan, Roy Maartens, Obinna Umeh +1
The first direct measurements of the HI intensity mapping power spectrum were recently made using the MeerKAT telescope. These measurements are on nonlinear scales, at redshifts 0.…
Vorticity generation in cosmology and the role of shell crossing
Obinna Umeh
There is no source for cosmic vorticity within the cold dark matter cosmology. However, vorticity has been observed in the universe, especially on the scales of clusters, filaments…
Emergence of smooth distance and apparent magnitude in a lumpy Universe
Obinna Umeh
The standard interpretation of observations such as the peak apparent magnitude of Type Ia supernova made from one location in a lumpy Universe is based on the idealised Friedmann-…
Consequences of using a smooth cosmic distance in a lumpy universe: I
Obinna Umeh
How do we appropriately fit a model based on an idealised Friedmann-Lema\^{}tre Robertson-Walker spacetime to observations made from a single location in a lumpy Universe? We addre…