相关论文: Has JWST already falsified dark-matter-driven gala…
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…
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…
Early data from JWST have revealed a bevy of high-redshift galaxy candidates with unexpectedly high stellar masses. An immediate concern is the consistency of these candidates with galaxy formation in the standard cosmological model. In the…
The James Webb Space Telescope (JWST) has unveiled a population of unexpectedly massive and luminous galaxies at redshifts $z \gtrsim 7$, posing a significant challenge to the standard $\Lambda$CDM cosmological paradigm. In this work, we…
Observations with the {\it James Webb Space Telescope} have revealed a high abundance of bright galaxies at redshift, $z\gtrsim 12$, which has been widely interpreted as conflicting with the $\Lambda$CDM model. In Cowley et al. (2018)…
Deep space observations of the James Webb Space Telescope (JWST) have revealed that the structure and masses of very early Universe galaxies at high redshifts (z~15), existing at ~0.3 Gyr after the BigBang, maybe as evolved as the galaxies…
The discovery of massive, high redshift galaxies with the James Webb Space Telescope (JWST) has been argued to challenge $\Lambda$CDM (cold dark matter): such systems would require extremely rare halos and baryon-to-stellar-mass conversion…
The James Webb Space Telescope (JWST) has discovered a surprising abundance of bright galaxy candidates in the very early Universe ($< 500$ Myrs after the Big Bang), calling into question current galaxy formation models. Spectroscopy is…
Early photometric results from JWST have revealed a number of galaxy candidates above redshift 10. The initial estimates of inferred stellar masses and the associated cosmic star formation rates are above most theoretical model predictions…
The James Webb Space Telescope continues to push back the redshift frontier to ever earlier cosmic epochs, with recent announcements of galaxy candidates at redshifts of $15 \lesssim z \lesssim 30$. We leverage the recent GUREFT suite of…
We report the discovery of 15 exceptionally luminous $10\lesssim z\lesssim14$ candidate galaxies discovered in the first 0.28 deg$^2$ of JWST/NIRCam imaging from the COSMOS-Web Survey. These sources span rest-frame UV magnitudes of…
The so-called `impossibly early galaxy' problem, first identified via the Hubble Space Telescope's observation of galaxies at redshifts z > 10, appears to have been exacerbated by the more recent James Webb Space Telescope (JWST) discovery…
We exploit the recent {\it James Webb Space Telescope} (JWST) determination of galaxy UV luminosity functions over the redshift range $z=9-14.5$ to derive constraints on warm dark matter (WDM) models. The delayed structure formation in WDM…
The early-science observations made by the James Webb Space Telescope (JWST) have revealed an excess of ultra-massive galaxy candidates that appear to challenge the standard cosmological model ($\Lambda$CDM). Here, we argue that any…
Recent JWST observations have revealed an unexpected abundance of massive galaxy candidates in the early Universe, extending further in redshift and to lower luminosity than what had previously been found by sub-millimeter surveys. These…
The James Webb Space Telescope (JWST), which has recently become operational, is capable of detecting objects at record-breaking redshifts, $z \gtrsim 15$. This is a crucial advance for observational cosmology, as at these redshifts the…
Surveys with James Webb Space Telescope (JWST) have discovered candidate galaxies in the first 400 Myr of cosmic time. Preliminary indications have suggested these candidate galaxies may be more massive and abundant than previously thought.…
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…
One of the main goals of the JWST is to study the first galaxies in the Universe. We present a systematic photometric analysis of very distant galaxies in the first JWST deep field towards the massive lensing cluster SMACS0723. As a result,…
With the advent of JWST, we can probe the rest-frame optical emission of galaxies at $z>3$ with high sensitivity and spatial resolution, making it possible to accurately characterise red, optically-faint galaxies and thus move towards a…