Dark Energy & Dark Matter

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National Aeronautics and Space Administration The two largest pieces of the Universe, dark matter and dark energy, are the two that we know the least about, yet nothing less than the ultimate fate of the Universe will be determined by them. DARK ENERGY DARK MATTER TENDS TO DRIVE THE UNIVERSE TENDS TO DRIVE THE UNIVERSE APART. TOGETHER. 69% 26% 5% EVERYTHING ELSE, INCLUDING ALL STARS, Results from viewing PLANETS, AND US Ever since the phenomenal Type Ia supernovas have success of Isaac Newton in explaining shown astronomers that the motion of the planets with his theory the expansion of the Universe of gravity and laws of motion in 1687, is accelerating and dark energy unseen matter has been invoked to explain is the reason for the acceleration. puzzling observations of cosmic bodies. The two basic models for dark energy are that it is either energy associated with empty space (vacuum energy) and is constant throughout space and time, or it is an energy field that varies over space Evidence suggest that the mass of dark and time. matter in galaxies, clusters of galaxies, and the Universe as a whole is about 5 or 6 times greater than the mass of ordinary baryonic matter such as protons and neutrons. If vacuum energy is correct, in about 100 billion years, Dark matter is thought to be no galaxy outside our own mostly composed of exotic will be visible. particles formed when the Universe was a fraction of a Big second old. If it is an energy field, Rip depending on the Constant Dark nature, expansion Energy could stop and become Scale of the Universe The issue of whether dark a collapse, or the Big matter exists or the theory of acceleration could Crunch gravity needs to be modified will increase without limit. likely not be resolved until dark Big Bang Present Future matter particles are detected, or ruled out by lack of detection. If dark energy does not exist, cosmic acceleration Some physicists could be a sign that the propose actually theory of gravity needs to making dark matter. be modified for extremely large distance scales. HTTP://CHANDRA.SI.EDU/LEARN_COSMOLOGY.HTML www.nasa.gov.

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Dark Energy and Dark Matter As Inertial Effects Introduction
Dark Energy and Dark Matter as Inertial Effects Serkan Zorba Department of Physics and Astronomy, Whittier College 13406 Philadelphia Street, Whittier, CA 90608 [email protected] ABSTRACT A disk-shaped universe (encompassing the observable universe) rotating globally with an angular speed equal to the Hubble constant is postulated. It is shown that dark energy and dark matter are cosmic inertial effects resulting from such a cosmic rotation, corresponding to centrifugal (dark energy), and a combination of centrifugal and the Coriolis forces (dark matter), respectively. The physics and the cosmological and galactic parameters obtained from the model closely match those attributed to dark energy and dark matter in the standard Λ-CDM model. 20 Oct 2012 Oct 20 ph] - PACS: 95.36.+x, 95.35.+d, 98.80.-k, 04.20.Cv [physics.gen Introduction The two most outstanding unsolved problems of modern cosmology today are the problems of dark energy and dark matter. Together these two problems imply that about a whopping 96% of the energy content of the universe is simply unaccounted for within the reigning paradigm of modern cosmology. arXiv:1210.3021 The dark energy problem has been around only for about two decades, while the dark matter problem has gone unsolved for about 90 years. Various ideas have been put forward, including some fantastic ones such as the presence of ghostly fields and particles. Some ideas even suggest the breakdown of the standard Newton-Einstein gravity for the relevant scales. Although some progress has been made, particularly in the area of dark matter with the nonstandard gravity theories, the problems still stand unresolved.
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Dark Matter and the Early Universe: a Review Arxiv:2104.11488V1 [Hep-Ph
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Dark Energy and Dark Matter
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