Cosmic Clumping: Understanding Large-Scale Structures in the Universe скачать в хорошем качестве

Cosmic Clumping: Understanding Large-Scale Structures in the Universe

#BigBang #CosmicStructure #Galaxies #DarkMatter #Cosmology #Astrophysics #Superclusters #Universe #SpaceScience #GalacticFormation This time, we continue our exploration of Big Bang cosmology. We’ve discussed homogeneity and isotropy, the redshift and expansion of the universe, the cosmic microwave background, and Big Bang nucleosynthesis. Now, we’ll explore the formation of large-scale structures in the universe, the last pillar of Big Bang cosmology. Understanding Galaxy Clusters and Superclusters: The Virgo Cluster is a nearby example, situated about 67 million light years away with thousands of galaxies. Larger structures like the Laniakea Supercluster encompass many clusters, stretching over 500 million light years. These superclusters are gravitationally bound, demonstrating the cosmos’s vast interconnected structure. X-Ray Observations and Dark Matter: Galaxy clusters are dominated by hot gas visible in X-ray light, often outshining the starlight. This hot gas is found in the intercluster medium. Clusters like Abell 7047 exhibit this phenomenon, showing massive elliptical galaxies enveloped in diffuse X-ray halos, indicative of significant amounts of dark matter and hot gas. Mapping the Universe with Quasars: Quasars like 3C273, incredibly luminous and distant, allow us to map interstellar gas. The absorption lines in the spectra of quasars form the Lyman alpha forest, revealing intervening gas clouds. These gas clouds and dark matter distribute along filaments and sheets, mapping the universe’s large-scale structure. Gravitational Lensing and Mass Mapping: Distant galaxies’ light, bent by massive foreground clusters, creates gravitational lenses. Observations of clusters like Abell 2218 using gravitational lensing reveal the distribution of dark matter. These lenses distort light, producing multiple images and arcs of background galaxies, helping map total cluster mass. Simulations and Large-Scale Structure Formation: Simulations like those at the National Center for Supercomputing Applications and the Millennium Simulation Project model the formation of cosmic structures. These simulations demonstrate how dark matter and galaxies evolve from the early universe to today. The Eagle simulation further shows how hot gas and galaxies form under these conditions. Comparing Simulations to Observations: Different simulations reveal how supernovae affect gas distribution. By comparing these simulations to actual observations, researchers refine models of galaxy and structure formation. Observations match these simulations, validating the models, especially regarding dark matter’s role and distribution. The Role of the Cosmic Microwave Background: The CMB’s power spectrum provides insights into the universe’s composition. The ratio of dark matter to normal matter is extracted from the peaks in the power spectrum. This data, combined with observations and simulations, confirms the universe’s age and structure, supporting the Big Bang model. Simulations and the CMB combined reveal that the universe is mostly dark energy and dark matter, with normal matter making up a small fraction. This cosmological model, matching observations and simulations, confirms that the Big Bang and subsequent cosmic evolution produced our universe’s current structure. Next time, we’ll delve into cosmic inflation and the universe’s ultimate fate. See you then! Some simulations were performed at the National Center for Supercomputer Applications by Andrey Kravtsov (The University of Chicago) and Anatoly Klypin (New Mexico State University): http://cosmicweb.uchicago.edu/ Planck simulations of CMB transit: http://sci.esa.int/planck/51606-gravi... Large-scale structure: https://en.wikipedia.org/wiki/Observa... NASA's Hubble, Chandra Find Clues that May Help Identify Dark Matter: https://www.nasa.gov/press/2015/march... Evolution of HI: 3C273 spectrum from HST/FOC z=0; z=3.6 QSO HIRES/Keck spectrum from M. Rauch: https://arxiv.org/pdf/astro-ph/980628... Gravity of Galaxy Cluster Abell 2218 Creates Giant Lens: http://hubblesite.org/image/942/news_... Gravitational lensing of distant star-forming galaxies: https://vimeo.com/175907461 Gravitational lens: https://en.wikipedia.org/wiki/Gravita... Einstein Cross: https://en.wikipedia.org/wiki/Einstei... Formation of the large-scale structure in the Universe: filaments: http://cosmicweb.uchicago.edu/filamen... The Millennium Simulation: https://wwwmpa.mpa-garching.mpg.de/mi... Rob Crain's EAGLE Simulation Project: https://vimeo.com/user4391791 Science Results from the Planck CMB Probe: https://www.cosmos.esa.int/web/planck CMB Anisotropies from Acoustic Oscillations: http://background.uchicago.edu/~whu/p... BOSS: Dark Energy and the Geometry of Space: http://www.sdss3.org/surveys/boss.php