相关论文: JWST early Universe observations and {\Lambda}CDM …
The James Webb Space Telescope (JWST) is reporting massive high redshift galaxies that appear challenging from the $\Lambda$CDM perspective. Interpreted as a cosmological problem, this necessitates the Planck collaboration underestimating…
Determining reliable ages for old stellar objects at different redshifts offers a powerful means to constrain cosmology without relying on a specific cosmological model: this is known as the cosmic clocks method. Globular clusters (GCs),…
Observations of the high redshift universe provide a promising avenue for constraining the nature of the dark matter (DM). This will be even more true with the advent of the James Webb Space Telescope (JWST). We run cosmological simulations…
We use data on the high-redshift evolution of the size distribution and luminosity function of galaxies to constrain the relationship between their star formation efficiency and starburst lifetime. Based on the derived scaling relations, we…
If the Universe is dominated by cold dark matter and dark energy as in the currently popular LCDM cosmology, it is expected that large scale structures form gradually, with galaxy clusters of mass M > ~10^14 Msun appearing at around 6 Gyrs…
The massive and bright galaxies observed by the James Webb Space Telescope (JWST) at high redshifts ($z > 6$) have challenged our understanding of the Universe. This may require revisiting the physics of galaxy formation and evolution, or…
The growth of structure probes the re-ionization history and quasar abundance in the Universe, constituting an important probe of the cosmological predictions. Halos are not directly observable, however, so their mass and evolution must be…
Studies of the distant Universe are providing key insights into our understanding of the formation of galaxies. The advent of the James Webb Space Telescope (JWST) has significantly enhanced our observational capabilities, leading to an…
The distribution of dark matter halo masses can be accurately predicted in the $\Lambda$CDM cosmology. The presence of a single massive halo or galaxy at a particular redshift, assuming some baryon and stellar fraction for the latter, can…
The JWST discovery of a number of super-early (redshift $z>10$), blue galaxies requires these systems to be essentially dust-free in spite of their large stellar masses. A possible explanation is that dust is evacuated by radiatively-driven…
The concordance (LambdaCDM) model reproduces the main current cosmological observations assuming the validity of general relativity at all scales and epochs, the presence of cold dark matter, and of a cosmological constant, equivalent to a…
An unprecedented array of new observational capabilities are starting to yield key constraints on models of the epoch of first light in the Universe. In this Letter we discuss the implications of the UV radiation background at cosmic dawn…
The current hierarchical merging paradigm and $\Lambda$CDM predict that the $z \sim 4-8$ universe should be a time in which the most massive galaxies are transitioning from their initial halo assembly to the later baryonic evolution seen in…
We have investigated the properties of a bright K-band selected sample of early-type galaxies in the Hubble Deep Field, as representative of the field galaxy population. This dataset is unique as for the morphological information on faint…
Early JWST observations reveal an unexpectedly abundant population of high-redshift candidate massive galaxies at $z \gtrsim 7$, and recent DESI measurements show a preference for dynamical dark energy, which together present a significant…
Using a semi-analytic galaxy-formation model, we study analogues of 8 recently discovered JWST galaxies at $z>{\sim}12$. We select analogues from a cosmological simulation with a $(311{\rm cMpc})^3$ volume and an effective particle number…
We provide a review of our current knowledge of galaxies throughout the first billion years of cosmic history. This field has undergone a transformation in the last two years following the launch of $\textit{JWST}$, and we aim to deliver an…
The high-redshift galaxy UV luminosity function (UVLF) has become essential for understanding the formation and evolution of the first galaxies. Yet, UVLFs only measure galaxy abundances, giving rise to a degeneracy between the mean galaxy…
Recent photometric detections of extreme $(z>10)$ redshift galaxies from the JWST have been shown to be in strong tension with existing simulation models for galaxy formation, and in the most acute case, in tension with $\Lambda CDM$…
We compare properties of high-redshift galaxies observed by JWST with hydrodynamical simulations, in the standard cold dark matter model and in warm dark matter models with a suppressed linear matter power spectrum. We find that current…