cosmology Archives

Upper panels: Cosmic star formation rate density, as computed with our extension of the SP21 model (dashed black line) and as given by the original SP21 model (dot-dashed red line). In the left panel, we further show with the empirical fit (dotted black line) to a compilation of observational data provided by Madau & Dickinson (2014) (grey data points). The right panel shows the behaviour of the SP21 model and our extended formalism in the future of the universe. As future times correspond to negative redshifts, and the cosmic star formation rate density becomes asymptotically null at arbitrarily large times, both axes switch from logarithmic to linear scale when moving from the left to the right panel. The grey hatched shaded area in the right panel excludes the non-physical region corresponding to 𝜌¤∗ < 0. Lower panels: Relative difference between the two models showed above (dashed black line), and between our formalism and the fit from Madau & Dickinson (2014) (dotted black line). The latter comparison is available only for positive redshifts (i.e., past cosmic times), as the fit represents a purely empirical fit to the data, and not a predictive theoretical model. The SP21 model agrees well with the improved method introduced in this work at high redshift, but overestimates the cosmic star formation rate density at lower redshift and in the future. In the redshift range 0 < 𝑧 < 10, both the original SP21 model and our updated formalism agree with the empirical fit within a factor of ∼ 2. -- astro-ph.CO

Astronomy & Telescopes, Status Report, Stellar Cartography

The Impact Of The Cosmological Constant On Past And Future Star Formation

by Keith CowingNovember 23, 2024November 23, 2024

We present an extended analytic model for cosmic star formation, with the aim of investigating the impact of cosmological parameters on the star formation history within the ΛCDM paradigm.

This Hubble Space Telescope image captures a triple-star system, which can host potentially-habitable planets. Our nearest stellar neighbour, the Alpha Centauri system, includes three stars. Credit NASA, ESA, G. Duchene (Universite de Grenoble I); Image Processing: Gladys Kober (NASA/Catholic University of America)

Astronomy & Telescopes, Biosignatures & Paleobiology, Imaging & Spectroscopy, Intelligence & Language, Interstellar, Origin & Evolution of Life, People Of Astrobiology, Press Release, SETI & Technosignatures, Stellar Cartography

A New Model Calculates The Chances Of Intelligent Life Elsewhere

by Keith CowingNovember 13, 2024November 13, 2024

The chances of intelligent life emerging in our Universe – and in any hypothetical ones beyond it – can be estimated by a new theoretical model which has echoes of […]

Gigantic infrared map of the Milky Way, ESO Larger images

Astronomy & Telescopes, Imaging & Spectroscopy, Press Release, Stellar Cartography

ESO Telescope Captures The Most Detailed Infrared Map Ever Of Our Home Galaxy

by Keith CowingSeptember 27, 2024September 27, 2024

Astronomers have published a gigantic infrared map of the Milky Way containing more than 1.5 billion objects ― the most detailed one ever made. Using the European Southern Observatory’s VISTA […]

A 2D visual comparison of the filaments identified by DisPerSE from the DTFE density field (left) and the MCPM density field (right) in the same 10 Mpc thick slices in TNG100 at z = 0. In both panels, the underlying DM overdensity along the line of sight is represented by the blue–white color bar, and gray circles represent galaxies. The individual filament segments from DTFE and MCPM are curves colored by the average persistence value of a segment (red is less persistent, yellow is more persistent). The MCPM density field identifies the filamentary structure with significantly higher fidelity, including the less prominent filaments that the DTFE density field method misses. -- The Astronomical Journal

Astronomy & Telescopes, Gaia - Planetary Perspectives, Interstellar, Microbiology & Virology, Science Fiction, Status Report, Stellar Cartography

Filaments Of The Slime Mold Cosmic Web and How They Affect Galaxy Evolution

by Keith CowingSeptember 17, 2024September 17, 2024

We present a novel approach for identifying cosmic web filaments within the DisPerSE structure identification framework, using cosmic density field estimates from the Monte Carlo Physarum Machine (MCPM), inspired by […]

The NIRCam (Near-Infrared Camera) instrument on NASA’s James Webb Space Telescope’s reveals a portion of the Milky Way’s dense core in a new light. An estimated 500,000 stars shine in this image of the Sagittarius C (Sgr C) region, along with some as-yet unidentified features. A large region of ionized hydrogen, shown in cyan, contains intriguing needle-like structures that lack any uniform orientation. NASA, ESA, CSA, STScI, and S. Crowe (University of Virginia). Download full resolution images for this article from the Space Telescope Science Institute.

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Interstellar, Press Release, SETI & Technosignatures

Webb’s View Of The Galactic Center. 500,000+ Stars. How Many Have Life-bearing Worlds?

by Keith CowingNovember 26, 2023November 26, 2023

The latest image from NASA’s James Webb Space Telescope shows a portion of the dense center of our galaxy in unprecedented detail, including never-before-seen features astronomers have yet to explain. […]

On the left panel, we have Himmelblau’s function, while the center panel displays its contour diagram. The red points on the contours represent the global minima of the function. On the right panel, we can observe the application of the genetic algorithm with niching and sharing, specifically for Himmelblau’s function. -- astro-ph.CO

AI - Data - Apps - Cybernetics, Astronomy & Telescopes, Genomics, Proteomics, Bioinformatics, Status Report

Cosmological Parameter Estimation With Genetic Algorithms

by Keith CowingNovember 14, 2023November 14, 2023

The search for the optimal values, maxima or minima, of a complex function is an essential task in several fields where mathematical modeling is required. Genetic algorithms (GAs) are a […]

Astronomy & Telescopes, Press Release

Slime Mold Simulations Used To Map Dark Matter Holding Universe Together

by Keith CowingMarch 10, 2020

The behavior of one of nature’s humblest creatures is helping astronomers probe the largest structures in the universe. The single-cell organism, known as slime mold (Physarum polycephalum), builds complex filamentary […]