Related papers: The Binding Energy Parameter for Common Envelope E…
The inclusion of a $\Lambda $ term, today, in the relativistic field equations is consequence of the evolution of an observational cosmology. In this work we argue the "ansatz" $\Lambda = \beta H^2 +\frac{\alpha}{R^2}$ is applicable to the…
We present a highly simplified model of the dynamical structure of a disk galaxy where only two parameters fully determine the solution, mass and angular momentum. We show through simple physical scalings that once the mass has been fixed,…
Luminous red novae trace unstable binary interactions in which common-envelope evolution can produce either a stellar merger or a surviving binary following envelope ejection. Recent population studies suggest that a substantial fraction of…
In the era of advanced electromagnetic and gravitational wave detectors, it has become increasingly important to effectively combine and study the impact of stellar evolution on binaries and dynamical systems of stars. Systematic studies…
The formation histories of compact binary mergers, especially stellar-mass binary-black hole mergers, have recently come under increased scrutiny and revision. In this paper we revisit the question of the dominant formation channel and…
Next year we will celebrate 100 years of the cosmological term, $\Lambda$, in Einstein's gravitational field equations, also 50 years since the cosmological constant problem was first formulated by Zeldovich, and almost about two decades of…
An analysis of the astrophysical $S$ factor of the proton-proton weak capture ($\mathrm{p}+\mathrm{p}\rightarrow {}^2\mathrm{H}+\mathrm{e}^++\nu_{\mathrm{e}}$) is performed on a large energy range covering solar-core and early Universe…
A depth of $D_{\Lambda}\approx -28$ MeV for the $\Lambda$-nucleus potential was confirmed in 1988 by studying $\Lambda$ binding energies deduced from $(\pi^+,K^+)$ spectra measured across the periodic table. Modern two-body hyperon-nucleon…
In this paper we emphasize the close connection between the chemical and spectrophotometric evolution of stellar systems: Chemical yields from stars correspond to a precise fraction of their emitted light. We translate this concept…
Motivated by the possible existence of other universes, with possible variations in the laws of physics, this paper explores the parameter space of fundamental constants that allows for the existence of stars. To make this problem…
We propose a time-varying cosmological constant with a fixed equation of state, which evolves mainly through its interaction with the background during most of the long history of the universe. However, such interaction does not exist in…
The idea here is to set the cosmical constant $\lambda$ proportional to the scalar of the stress-energy tensor of the ordinary matter. We investigate the evolution of the scale factor in a cosmological model in which the cosmological…
We formulate the basic framework of thermodynamical entropic force cosmology which allows variation of the gravitational constant $G$ and the speed of light $c$. Three different approaches to the formulation of the field equations are…
Binary population synthesis is the method by which predictions of varied observables of stellar populations can be made from theoretical models of binary stellar evolution. Binary stars have many more possible evolutionary outcomes compared…
We investigate the common envelope binary interaction, that leads to the formation of compact binaries, such as the progenitor of Type Ia supernovae or of mergers that emit detectable gravitational waves. In this work we diverge from the…
We argue that outward transport of energy by convection and photon diffusion in a common envelope evolution (CEE) of giant stars substantially reduces the fraction of the recombination energy of hydrogen and helium that is available for…
Massive binary evolution models are needed to predict massive star populations in star forming galaxies, the supernova diversity, and the number and properties of gravitational wave sources. Such models are often computed using so called…
Some of the arguments which support the strong concensus for an $\Omega_o$ = 0.3, $\lambda_o$ = 0.7 model are reexamined. Corrections for Malmquist bias, local flow and metallicity suggest a revised value for $H_o$ of 63 $\pm$ 6 km/s/Mpc,…
Over the past decades, cosmology has become largely based on experimental data, the most important sources of which are studies of the cosmic microwave background (CMB). CMB is present in the Universe since the very first moments of its…
We derive new limits on the value of the cosmological constant, $\Lambda$, based on the Einstein bending of light by systems where the lens is a distant galaxy or a cluster of galaxies. We use an amended lens equation in which the…