Related Research Articles
The Big Bang is a physical theory that describes how the universe expanded from an initial state of high density and temperature. It was first proposed in 1931 by Roman Catholic priest and physicist Georges Lemaître when he suggested the universe emerged from a "primeval atom". Various cosmological models of the Big Bang explain the evolution of the observable universe from the earliest known periods through its subsequent large-scale form. These models offer a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background (CMB) radiation, and large-scale structure. The overall uniformity of the universe, known as the flatness problem, is explained through cosmic inflation: a sudden and very rapid expansion of space during the earliest moments. However, physics currently lacks a widely accepted theory of quantum gravity that can successfully model the earliest conditions of the Big Bang.
Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the universe and allows study of fundamental questions about its origin, structure, evolution, and ultimate fate. Cosmology as a science originated with the Copernican principle, which implies that celestial bodies obey identical physical laws to those on Earth, and Newtonian mechanics, which first allowed those physical laws to be understood.
In astronomy, dark matter is a hypothetical form of matter that appears not to interact with light or the electromagnetic field. Dark matter is implied by gravitational effects which cannot be explained by general relativity unless more matter is present than can be seen. Such effects occur in the context of formation and evolution of galaxies, gravitational lensing, the observable universe's current structure, mass position in galactic collisions, the motion of galaxies within galaxy clusters, and cosmic microwave background anisotropies.
The universe is all of space and time and their contents. It comprises all of existence, any fundamental interaction, physical process and physical constant, and therefore all forms of energy and matter, and the structures they form, from sub-atomic particles to entire galaxies. Space and time, according to the prevailing cosmological theory of the Big Bang, emerged together 13.787±0.020 billion years ago, and the universe has been expanding ever since. Today the universe has expanded into an age and size that is physically only in parts observable as the observable universe, which is approximately 93 billion light-years in diameter at the present day, while the spatial size, if any, of the entire universe is unknown.
Sandra Moore Faber is an American astrophysicist known for her research on the evolution of galaxies. She is the University Professor of Astronomy and Astrophysics at the University of California, Santa Cruz, and works at the Lick Observatory. She has made discoveries linking the brightness of galaxies to the speed of stars within them and was the co-discoverer of the Faber–Jackson relation. Faber was also instrumental in designing the Keck telescopes in Hawaii.
In cosmology and physics, cold dark matter (CDM) is a hypothetical type of dark matter. According to the current standard model of cosmology, Lambda-CDM model, approximately 27% of the universe is dark matter and 68% is dark energy, with only a small fraction being the ordinary baryonic matter that composes stars, planets, and living organisms. Cold refers to the fact that the dark matter moves slowly compared to the speed of light, giving it a vanishing equation of state. Dark indicates that it interacts very weakly with ordinary matter and electromagnetic radiation. Proposed candidates for CDM include weakly interacting massive particles, primordial black holes, and axions.
Plasma cosmology is a non-standard cosmology whose central postulate is that the dynamics of ionized gases and plasmas play important, if not dominant, roles in the physics of the universe at interstellar and intergalactic scales. In contrast, the current observations and models of cosmologists and astrophysicists explain the formation, development, and evolution of large-scale structures as dominated by gravity.
Astrophysics is a science that employs the methods and principles of physics and chemistry in the study of astronomical objects and phenomena. As one of the founders of the discipline, James Keeler, said, Astrophysics "seeks to ascertain the nature of the heavenly bodies, rather than their positions or motions in space–what they are, rather than where they are." Among the subjects studied are the Sun, other stars, galaxies, extrasolar planets, the interstellar medium and the cosmic microwave background. Emissions from these objects are examined across all parts of the electromagnetic spectrum, and the properties examined include luminosity, density, temperature, and chemical composition. Because astrophysics is a very broad subject, astrophysicists apply concepts and methods from many disciplines of physics, including classical mechanics, electromagnetism, statistical mechanics, thermodynamics, quantum mechanics, relativity, nuclear and particle physics, and atomic and molecular physics.
Michael S. Turner is an American theoretical cosmologist who coined the term dark energy in 1998. He is the Rauner Distinguished Service Professor Emeritus of Physics at the University of Chicago, having previously served as the Bruce V. & Diana M. Rauner Distinguished Service Professor, and as the assistant director for Mathematical and Physical Sciences for the US National Science Foundation.
Margaret J. Geller is an American astrophysicist at the Center for Astrophysics | Harvard & Smithsonian. Her work has included pioneering maps of the nearby universe, studies of the relationship between galaxies and their environment, and the development and application of methods for measuring the distribution of matter in the universe.
Marc Davis is an American professor of astronomy and physics at the University of California, Berkeley. Davis received his bachelor's degree from the Massachusetts Institute of Technology in 1969, his Ph.D from Princeton University in 1973 and has been elected to both the National Academy of Sciences (1991) and the American Academy of Arts and Sciences (1992). He taught for a year at Princeton, 1973–74, then was on the astronomy faculty at Harvard from 1975 to 1981. Since 1981, he has been on the faculty of the Department of Astronomy and Physics at the University of California at Berkeley.
Carlos Silvestre Frenk is a Mexican-British cosmologist. Frenk graduated from the National Autonomous University of Mexico and the University of Cambridge and spent his early research career in the United States, before settling permanently in the United Kingdom. He joined the Durham University Department of Physics in 1986 and since 2001 has served as the Ogden Professor of Fundamental Physics at Durham University.
George R. Blumenthal is an American astrophysicist, astronomer, and academic administrator. He was the tenth chancellor of the University of California, Santa Cruz.
Simon David Manton White, FRS, is a British-German astrophysicist. He was one of directors at the Max Planck Institute for Astrophysics before his retirement in late 2019.
Paul S. Wesson, B.Sc., Ph.D., D.Sc., F.R.A.S was a professor of astrophysics and theoretical physics.
The Bolshoi simulation, a computer model of the universe run in 2010 on the Pleiades supercomputer at the NASA Ames Research Center, was the most accurate cosmological simulation to that date of the evolution of the large-scale structure of the universe. The Bolshoi simulation used the now-standard ΛCDM (Lambda-CDM) model of the universe and the WMAP five-year and seven-year cosmological parameters from NASA's Wilkinson Microwave Anisotropy Probe team. "The principal purpose of the Bolshoi simulation is to compute and model the evolution of dark matter halos, thereby rendering the invisible visible for astronomers to study, and to predict visible structure that astronomers can seek to observe." “Bolshoi” is a Russian word meaning “big.”
The University of California High-Performance AstroComputing Center (UC-HiPACC) based at the University of California at Santa Cruz (UCSC) is a consortium of nine University of California campuses and three Department of Energy laboratories. The consortium's goal is to support and facilitate original research and education in computational astrophysics and to engage in public outreach and education.
Risa H. Wechsler is an American cosmological physicist, Professor of Physics at Stanford University, and Professor of Particle Physics and Astrophysics at SLAC National Accelerator Laboratory. She is the director of the Kavli Institute for Particle Astrophysics and Cosmology.
Bernard Sadoulet is a French physicist.
Joshua A. Frieman is a theoretical astrophysicist who lives and works in the United States. He is a senior scientist at Fermilab and a professor of astronomy and astrophysics at the University of Chicago. Frieman is known for his work studying dark energy and cosmology, and he co-founded the Dark Energy Survey experiment. He was elected a member of the National Academy of Sciences in 2022.
References
- ↑ "Joel R. Primack" . Retrieved 29 April 2024.
- ↑ "Welcome from the Director" . Retrieved 29 January 2013.
- ↑ Blumenthal; et al. (11 Oct 1984). "Formation of galaxies and large-scale structure with cold dark matter" (PDF). Nature. 311 (5986): 517–525. Bibcode:1984Natur.311..517B. doi:10.1038/311517a0. OSTI 1447148. S2CID 4324282.
- ↑ Joel R. Primack, "Dark Matter, Galaxies, and Large Scale Structure in the Universe", SLAC-PUB-3387 (July 1984), in Proceedings of the International School of Physics XCII 1987
- ↑ The View from the Center of the Universe. Joel R. Primack and Nancy Ellen Abrams, Riverhead Books, 2007 ( ISBN 978-1594482557).
- ↑ The New Universe and the Human Future - The Terry Lectures. Joel R. Primack and Nancy Ellen Abrams, Yale University Press, 2012 ( ISBN 978-0300181241).
- ↑ David Hafemeiste. "History of the Forum on Physics and Society". Forum on Physics and Society, Vol 28, p 3-5. ; Link in APS website
