148 citations · 313 across the 10 of their papers we have counts for
12 papers
Earthquakes as probing tools for gravity theories
Aleksander Kozak, Aneta Wojnar
We propose a novel method for testing gravity models using seismic data from Earth. By imposing observational constraints on Earth's moment of inertia and mass, we rigorously limit…
Planetary seismology as a test of modified gravity proposals
Aleksander Kozak, Aneta Wojnar
We demonstrate that it is possible to test models of gravity, such as Palatini and Eddington-inspired Born-Infeld models, using seismic data from Earth. By incorporating add…
Cooling process of substellar objects in scalar-tensor gravity
Aleksander Kozak, Kärt Soieva, Aneta Wojnar
Cooling processes of brown dwarf stars and giant planets are studied in the framework of DHOST theories. We confirm the previous results in the field that the effect of modified gr…
Interiors of terrestrial planets in metric-affine gravity
Aleksander Kozak, Aneta Wojnar
Using a semi-empirical approach we show that modified gravity affects the internal properties of terrestrial planets, such as their physical characteristics of a core, mantle, and…
Non-homogeneous exoplanets in metric-affine gravity
Aleksander Kozak, Aneta Wojnar
The improved description of the planets' interior is provided. We examine the modified gravity effects on the Earth-like planets composed of the iron core and silicate mantle. We c…
Scalar-tensor cosmologies in a minisuperspace formulation: a case study
Andrzej Borowiec, Aleksander Kozak
We revisit a general minisuperspace (MSS) formalism for scalar-tensor (ST) FLRW type cosmological models in arbitrary frame with perfect fluid source. We discuss how to impose Cauc…
Metric-affine gravity effects on terrestrial (exo-)planets profiles
Aleksander Kozak, Aneta Wojnar
Mass-radius relations of homogeneous cold spheres are obtained for six solid materials commonly found in terrestrial planets. An additional degeneracy in the (exo-)planets' profile…
Invariant quantities of Scalar-Tensor Theories for stellar structure
Aleksander Kozak, Aneta Wojnar
We present the relativistic hydrostatic equilibrium equations for a wide class of gravitational theories possessing a scalar-tensor representation. It turns out that the stellar st…
Equivalence of inflationary models between the metric and Palatini formulation of scalar-tensor theories
Laur Järv, Alexandros Karam, Aleksander Kozak +3
With a scalar field non-minimally coupled to curvature, the underlying geometry and variational principle of gravity - metric or Palatini - becomes important and makes a difference…
New class of hybrid metric-Palatini scalar-tensor theories of gravity
Andrzej Borowiec, Aleksander Kozak
A class of scalar-tensor theories (STT) including a non-metricity that unifies metric, Palatini and hybrid metric-Palatini gravitational actions with non-minimal interaction is pro…
Learning ReLU Networks on Linearly Separable Data: Algorithm, Optimality, and Generalization
Gang Wang, Georgios B. Giannakis, Jie Chen
Neural networks with REctified Linear Unit (ReLU) activation functions (a.k.a. ReLU networks) have achieved great empirical success in various domains. Nonetheless, existing result…
Scalar-tensor gravity in the Palatini approach
Aleksander Kozak
The main objective of this thesis is to discuss scalar-tensor theories in the Palatini approach. Both scalar-tensor theories and Palatini formalism are means of alternating classic…