15 papers
Joint reconstruction of and with physics informed neural networks
Konstantinos F. Dialektopoulos
We present a model-independent joint reconstruction of the Hubble parameter and the growth rate using a dual-head physics-informed neural network trained on four…
Model-independent calibration of Gamma-Ray Bursts with neural networks
Purba Mukherjee, Maria Giovanna Dainotti, Konstantinos F. Dialektopoulos +2
The Cold Dark Matter (CDM) cosmological model has been highly successful in predicting cosmic structure and evolution, yet recent precision measurements have highlighted d…
Inflation driven by repulsive-like primordial black holes
Konstantinos Dialektopoulos, Theodoros Papanikolaou, Vasilios Zarikas
We review a new natural inflationary mechanism operated by repulsive-like primordial black holes (PBHs). In particular, working within the ``Swiss - Cheese" cosmological framework,…
Do equation of state parametrizations of dark energy faithfully capture the dynamics of the late universe?
Ãzgür Akarsu, Maria Caruana, Konstantinos F. Dialektopoulos +3
We investigate how strongly late-time inferences about DE dynamics depend on the functional prior used to represent the expansion history. Using identical late-time combinations of…
Cosmology of Cubic Poincaré Gauge gravity
Sebastian Bahamonde, Rebecca Briffa, Konstantinos Dialektopoulos +2
In this paper, we study flat FLRW cosmology for a Poincaré gauge theory containing cubic invariants that is free from ghosts in arbitrary backgrounds in the axial and vector secto…
Hints of sign-changing scalar field energy density and a transient acceleration phase at from model-agnostic reconstructions
Ãzgür Akarsu, Maria Caruana, Konstantinos F. Dialektopoulos +3
We present a data-driven reconstruction of the late-time expansion history and its implications for dark-energy dynamics. Modeling the reduced Hubble rate with a node-based Gaussia…