23 citations · 43 across the 5 of their papers we have counts for
5 papers
The dark energy as a natural property of cosmic polytropes -- A tutorial
Kostas Kleidis, Nikolaos K. Spyrou
Theoretical results on a conventional approach to the dark energy (DE) concept are reviewed and discussed. According to them, there is absolutely no need for a novel DE component i…
Cosmological perturbations in the CDM-like limit of a polytropic dark matter model
Kostas Kleidis, Nikolaos K. Spyrou
In a recent article, Kleidis and Spyrou (2015) proposed that both dark matter (DM) and dark energy (DE) can be treated as a single component, if accommodated in the context of a po…
Dark Energy: The Shadowy Reflection of Dark Matter?
Kostas Kleidis, Nikolaos K. Spyrou
In this article, we review a series of recent theoretical results regarding a conventional approach to the dark energy (DE) concept. This approach is distinguished among others for…
Newtonian nonlinear hydrodynamics and magnetohydrodynamics
N. K. Spyrou, C. G. Tsagas
We use covariant methods to analyse the nonlinear evolution of self-gravitating, non-relativistic media. The formalism is first applied to imperfect fluids, aiming at the kinematic…
Evolutionary Self-Energy-Loss Effects in Compact Binary Systems: Importance of Rapid Rotation and of Equation of State
N. K. Spyrou, N. Stergioulas
The spin-down of a millisecond pulsar in a compact binary system leads to self-energy losses, that cause the binary's orbital period to increase (the effect being of first post-New…