A number of challenges to the standard Λ CDM model have been emerging during the past
few years as the accuracy of cosmological observations improves. In this review we discuss …

The simplest ΛCDM model provides a good fit to a large span of cosmological data but
harbors large areas of phenomenology and ignorance. With the improvement of the number …

Measurement of the distances to nearby galaxies has improved rapidly in recent decades.
The ever-present challenge is to reduce systematic effects, especially as greater distances …

We present a measurement of the Hubble constant (H 0) and other cosmological parameters
from a joint analysis of six gravitationally lensed quasars with measured time delays. All …

The H0LiCOW collaboration inferred via strong gravitational lensing time delays a Hubble
constant value of km s− 1 Mpc− 1, describing deflector mass density profiles by either a …

We present a new and independent determination of the local value of the Hubble constant
based on a calibration of the tip of the red giant branch (TRGB) applied to Type Ia …

▪ The Hubble parameter, H 0, is not an univocally defined quantity: It relates redshifts to
distances in the near Universe, but it is also a key parameter of the ΛCDM standard …

We present a blind time-delay strong lensing (TDSL) cosmographic analysis of the doubly
imaged quasar SDSS 1206+ 4332. We combine the relative time delay between the quasar …

Multiply imaged time-variable sources can be used to measure absolute distances as a
function of redshifts and thus determine cosmological parameters, chiefly the Hubble …

One of the most exciting and pressing issues in cosmology today is the discrepancy
between some measurements of the local Hubble constant and other values of the …