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Related papers: Galaxy Formation in the Early Universe

200 papers

We review theoretical approaches to the study of galaxy formation, with emphasis on the role of hydrodynamic simulations in modeling the high redshift galaxy population. We present new predictions for the abundance of star-forming galaxies…

Astrophysics · Physics 2007-05-23 David H. Weinberg , Romeel Dave' , Jeffrey P. Gardner , Lars Hernquist , Neal Katz

Within the established framework of structure formation, galaxies start as systems of low stellar mass and gradually grow into far more massive galaxies. The existence of massive galaxies in the first billion years of the Universe,…

In the local Universe, star formation is typically inefficient both globally and when considered as the fraction of gas converted into stars per local free-fall time. An important exception to this inefficiency is regions of high…

Astrophysics of Galaxies · Physics 2025-04-07 Michael Boylan-Kolchin

The emergence of supermassive black holes (SMBHs) in the early universe remains a topic of profound interest and debate. In this paper, we investigate the formation and growth of the first SMBHs within the framework of Modified Gravity…

Astrophysics of Galaxies · Physics 2024-03-12 Mohammad H. Zhoolideh Haghighi , John Moffat

Recent observations with JWST have identified several bright galaxy candidates at $z\gtrsim 10$, some of which appear unusually massive (up to $\sim 10^{11}\ \rm M_{\odot}$). Such early formation of massive galaxies is difficult to…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-05 Boyuan Liu , Volker Bromm

Observations from the James Webb Space Telescope (JWST) have unveiled several galaxies with stellar masses $M_*\gtrsim10^{10} M_\odot$ at redshifts $7.4\lesssim z\lesssim 9.1$. These remarkable findings indicate an unexpectedly high stellar…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-04 Pei Wang , Bing-Yu Su , Lei Zu , Yupeng Yang , Lei Feng

The James Webb Space Telescope (JWST) has unveiled unexpectedly massive galaxy candidates at high redshifts, challenging standard $\Lambda$CDM cosmological predictions. In this work, we study the predictions of more realistic dark matter…

Astrophysics of Galaxies · Physics 2026-03-17 Saeed Fakhry , Reyhaneh Vojoudi Salmani , Javad T. Firouzjaee

I review the current state of our understanding of the galaxy formation and evolution process from the modeler's perspective. With the advent of the cold dark matter model and the support of fast computers and advanced simulation…

Astrophysics · Physics 2007-05-23 Matthias Steinmetz

A simple model for the dynamics of the Magellanic Stream (MS), in the framework of modified gravity models is investigated. We assume that the galaxy is made up of baryonic matter out of context of dark matter scenario. The model we used…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Hosein Haghi , Sohrab Rahvar

Astrophysical data analysis of the weak-field predictions support the claim that modified gravity (MOG) theories provide a self-consistent, scale-invariant, universal description of galaxy rotation curves, without the need of non-baryonic…

Astrophysics of Galaxies · Physics 2009-08-09 J. R. Brownstein

The equation of motion in the generally covariant modified gravity (MOG) theory leads, for weak gravitational fields and non-relativistic motion, to a modification of Newton's gravitational acceleration law. In addition to the metric…

General Relativity and Quantum Cosmology · Physics 2019-05-24 M. A. Green , J. W. Moffat

We consider the cosmological consequences of a special scalar-tensor-vector theory of gravity, known as MOG (for MOdified Gravity), proposed to address the dark matter problem. This theory introduces two scalar fields $G(x)$ and $\mu(x)$,…

General Relativity and Quantum Cosmology · Physics 2018-02-14 Sara Jamali , Mahmood Roshan , Luca Amendola

The first few cycles of JWST have identified an overabundance of UV-bright galaxies and a general excess of UV luminosity density at $z\gtrsim10$ compared to expectations from most (pre-JWST) theoretical models. Moreover, some of the…

Astrophysics of Galaxies · Physics 2024-12-03 Harley Katz , Alexander P. Ji , O. Grace Telford , Peter Senchyna

A modified gravity (MOG) possesses a light, neutral vector particle called a ``phion'' associated with a vector field $\phi^\mu$, which forms a cold fluid of Bose-Einstein condensates before recombination with zero pressure and zero shear…

Astrophysics · Physics 2007-05-23 J. W. Moffat

Galaxies form and evolve in the context of their local and large-scale environments. Their baryonic content that we observe with imaging and spectroscopy is intimately connected to the properties of their dark matter halos, and to their…

Scalar-tensor theories of gravity that embrace conformal coupling to the scalar curvature are the focal point of cosmology on discussions of inflation and late-time accelerating universe. Although there exists a stringent nucleo-synthesis…

General Relativity and Quantum Cosmology · Physics 2022-04-26 M. Yoshimura

Studies of the molecular interstellar medium that fuels star formation and supermassive black hole growth in galaxies at cosmological distances have undergone tremendous progress over the past few years. Based on the detection of molecular…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-10 Dominik A. Riechers

The James Webb Space Telescope (JWST) has revealed unexpectedly rapid galaxy assembly in the early universe, in tension with models of star and galaxy formation. In the gas conditions typical of early galaxies, particularly their low…

The evolution of the galaxy stellar mass function is especially useful to test the current model of galaxy formation. Observational data have revealed a few inconsistencies with predictions from the $\Lambda {\rm CDM}$ model. For example,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Xi Kang , WeiPeng Lin , Ramin A. Skibba , Dongni Chen