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 …

Astronomical observations reveal a major deficiency in our understanding of physics—the
detectable mass is insufficient to explain the observed motions in a huge variety of systems …

The European Space Agency's Planck satellite, which was dedicated to studying the early
Universe and its subsequent evolution, was launched on 14 May 2009. It scanned the …

We present cosmological parameter results from the final full-mission Planck measurements
of the cosmic microwave background (CMB) anisotropies, combining information from the …

We present cosmological parameter results from the final full-mission Planck measurements
of the CMB anisotropies. We find good consistency with the standard spatially-flat 6 …

The isotropy of the late Universe and consequently of the X-ray galaxy cluster scaling
relations is an assumption greatly used in astronomy. However, within the last decade, many …

The Square Kilometre Array (SKA) is a planned large radio interferometer designed to
operate over a wide range of frequencies, and with an order of magnitude greater sensitivity …

Observations reveal a “bulk flow” in the local Universe which is faster and extends to much
larger scales than are expected around a typical observer in the standard ΛCDM cosmology …

This biennial Review summarizes much of particle physics. Using data from previous
editions, plus 2158 new measurements from 551 papers, we list, evaluate, and average …

The blackbody radiation left over from the Big Bang has been transformed by the expansion
of the Universe into the nearly isotropic 2.73 K cosmic microwave background. Tiny …