English
Related papers

Related papers: Galaxies as condensates

200 papers

The effective potential in the Grumiller's modified gravity [D. Grumiller, Phys. Rev. Lett {\bf 105}, 211303 (2010)] includes the Newtonian potential and a Rindler term. The fitting to the rotation curve data of eight galaxies suggests a…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-28 Hai-Nan Lin , Ming-Hua Li , Xin Li , Zhe Chang

We compare N-body simulations of isolated galaxies performed in both frameworks of modified Newtonian dynamics (MOND) and Newtonian gravity with dark matter (DM). We have developed a multigrid code able to efficiently solve the modified…

Astrophysics · Physics 2009-11-13 O. Tiret , F. Combes

Cosmologies including continuous matter creation are able to reproduce the main properties of the standard $\Lambda$CDM model, in particular in cases where the particle and entropy production rates are equal. These specific models,…

General Relativity and Quantum Cosmology · Physics 2011-03-07 Alain de Roany , J. A. de Freitas Pacheco

Stars with a different vertical motion relative to the galactic disk have a different average acceleration. According to Modified Newtonian Dynamics (MOND) theories they should therefore have a different average orbital velocity while…

Astrophysics of Galaxies · Physics 2016-01-27 Ben Margalit , Nir J. Shaviv

A metric-field approach to gravitation is presented. It is based on an idea of dependency of space-time properties on measuring instruments. Some bimetric equations that realize this idea are considered. They were tested by the binary…

General Relativity and Quantum Cosmology · Physics 2009-11-07 L. V. Verozub

Both microlensing surveys and radio-frequency observations of gas flow imply that the inner Milky Way is completely dominated by baryons, contrary to the predictions of standard cold dark matter (CDM) cosmology. We investigate the…

Astrophysics · Physics 2009-11-13 B. Famaey , J. Binney

We report that the density profiles of globular cluster (GC) systems in a sample of 17 early-type galaxies (ETGs) show breaks at the radii where the gravitational acceleration exerted by the stars equals the galactic acceleration scale…

Astrophysics of Galaxies · Physics 2019-09-04 Michal Bílek , Srdjan Samurović , Florent Renaud

Compact groups of galaxies have posed a number of challenging questions. Intensive observational and theoretical studies are now providing answers to many of these, and at the same time, are revealing unexpected new clues about the nature…

Astrophysics · Physics 2009-10-30 Paul Hickson

Analysis of the deepest available images of the sky, obtained by the Hubble Space Telescope, reveals a large number of candidate high-redshift galaxies. A catalogue of 1,683 objects is presented, with estimated redshifts ranging from $z=0$…

Astrophysics · Physics 2008-11-26 Kenneth M. Lanzetta , Amos Yahil , Alberto Fernandez-Soto

There are now 10 firm time delay measurements in gravitational lenses. The physics of time delays is well understood, and the only important variable for interpreting the time delays to determine H_0 is the mean surface mass density <k> (in…

Astrophysics · Physics 2007-05-23 C. S. Kochanek , P. L. Schechter

Recent astronomical observations of SNIa, CMB, as well as BAO in the Sloan Digital Sky Survey, suggest that the current Universe has entered a stage of an accelerated expansion with the transition redshift at $z \simeq 0.5$. While the…

Astrophysics · Physics 2010-11-11 Aleksandra Kurek , Marek Szydlowski

As the formation of cosmic structure continues to proceed, we observe one of the latest stages of this process in mergers of clusters of galaxies with other clusters, groups, and galaxies. The X-ray emitting hot plasma of these systems can…

High Energy Astrophysical Phenomena · Physics 2023-04-05 John ZuHone , Yuanyuan Su

Beginning with a simple model for the growth of structure, I consider the dissipationless evolution of a MOND-dominated region in an expanding Universe by means of a spherically symmetric N-body code. I demonstrate that the final virialized…

Astrophysics · Physics 2009-11-13 R. H. Sanders

The competition between CDM and MOND to account for the `missing mass' phenomena is asymmetric. MOND has clearly demonstrated that a characteristic acceleration $a_0$ underlies the data and understanding what gives rise to $a_0$ is an…

Astrophysics · Physics 2007-05-23 James Binney

We review the evolution of the cosmic average molecular gas density to large look-back times, using observations of rotational transitions of CO. Molecular gas is the fuel for star formation in galaxies. Deep searches for CO emission from…

The standard cosmological model, the $\Lambda$CDM model, is the most suitable description for our universe. This framework can explain the accelerated expansion phase of the universe but still is not immune to open problems when it comes to…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-01 Maria Giovanna Dainotti , Biagio De Simone , Giovanni Montani , Malgorzata Bogdan

A new family of nonrelativistic, Newtonian, non-quantum equilibrium configurations describing galactic halos is introduced, by considering strange quark matter conglomerates with masses larger than about 8 GeV as new possible components of…

Astrophysics of Galaxies · Physics 2020-10-21 Marco Merafina , Francesco G. Saturni , Catalina Curceanu , Raffaele Del Grande , Kristian Piscicchia

Cosmology requires at least half of the baryons in the Universe to be in the intergalactic medium, much of which is believed to form hot coronae around galaxies. Star-forming galaxies must be accreting from their coronae. HI observations of…

Astrophysics of Galaxies · Physics 2015-05-30 James Binney , Filippo Fraternali

The cosmological model best capable of fitting current observational data features two separate epochs during which the Universe is accelerating. During the earliest stages of the Universe, such acceleration is known as cosmological…

Astrophysics · Physics 2009-10-31 Andrew R Liddle

We show that the accelerated expansion of the Universe can be viewed as a crossover phenomenon where the Newton constant and the Cosmological constant are actually scaling operators, dynamically evolving in the attraction basin of a…

Astrophysics · Physics 2009-11-13 A. Bonanno , G. Esposito , C. Rubano , P. Scudellaro