Related papers: On the links between Astronomy, Astronomers, and S…

I discuss some aspects of the use of computers in Relativity, Astrophysics and Cosmology. For each section I provide two examples representative of the field, including gravitational collapse, black hole imagery, supernovae explosions,…

For most of its history, cosmology was a qualitatively constrained discourse on the universe, shaped by limited observational access and the absence of global dynamical laws. This situation has changed decisively in recent decades. Modern…

Cosmological discoveries over the past century have completely changed our picture of our place in the universe. New observations have a realistic chance of probing nature on heretofore unimaginable scales, and as a result are changing the…

We describe the experience of running an Astrophysics outreach initiative involving traditional mass media like radio broadcast and new digital media like blog, microblogging and internet video channel. Some very successful preliminary…

In an undulant universe, cosmic expansion is characterized by alternating periods of acceleration and deceleration. We examine cosmologies in which the dark-energy equation of state varies periodically with the number of e-foldings of the…

This paper is a discussion of the physics of magnification in telescopes. Special attention is given to the question of whether telescopes magnify stars. Telescopes do magnify star images, although opinions to the contrary abound.

Astronomy is the study of the Universe and all the objects that it comprises. Our attention is therefore usually focused beyond Earth, home to the only form of life known today. However, how can we continue to explore the secrets of the…

Over the past decade, astronomers have been using an increasingly larger number of web-based applications and archives to conduct their research. However, despite the early success in creating links across projects and data centers, the…

Galaxies represent the visible fabric of the Universe and there has been considerable progress recently in both observational and theoretical studies. The underlying goal is to understand the present-day diversity of galaxy forms, masses…

Over the next decade we will witness the development of a new infrastructure in support of data-intensive scientific research, which includes Astronomy. This new networked environment will offer both challenges and opportunities to our…

An amateur astronomer in the modern world has the opportunity not only to make visual observations for own interest, but can make scientific astronomical observations and new discoveries in astronomy. In my example, as amateur astronomer…

Dark matter has been introduced to explain many independent gravitational effects at different astronomical scales, in galaxies, groups of galaxies, clusters, superclusters and even across the full horizon. This review describes the…

"You don't look like a librarian" is a phrase we often hear in the astronomy department or observatory library. Astronomy librarians are a breed apart, and are taking on new and non-traditional roles as information technology evolves. This…

The stellar astronomy has always been considered the fundamental source of knowledge about the basic building blocks of the universe - the stars. It has proved correctness of many physical theories - like e.g. the idea of nuclear fusion in…

Over the past decade, sky surveys such as the Sloan Digital Sky Survey have proven the power of large data sets for answering fundamental astrophysical questions. This observational progress, based on a synergy of advances in telescope…

Despite the large budgets spent annually on astronomical research equipment such as telescopes, instruments and supercomputers, the general trend is to analyse and view the resulting datasets using small, two-dimensional displays. We report…

The accelerating expansion of the universe presents an exciting, fundamental challenge to the standard models of particle physics and cosmology. I highlight some of the outstanding challenges in both developing theoretical models and…

Here, we present a simple solution to problems that have plagued (extra)"galactic" astronomers and cosmologists over the last century. We show that "galaxy" formation, dark matter, and the tension in the expansion of the universe can all be…

Over the last 20 years, supernovae have become a key tool to constrain the expansion history of the Universe through the construction of Hubble diagrams, using luminosity distances to supernovae belonging to the "Ia" subtype. This technique…

This paper presents a brief overview of how astronomy can help society in COVID-19 times, and the lessons that come from studying our place in the Universe and the global coordination of scientific and outreach activities. Several examples…