Gravity has been tested extremely well inside the solar system. On cosmic scales, direct tests are harder. This study pushes ...

Scientists rely on two methods to measure the expansion of the universe: extrapolating from Cosmic Microwave Background (CMB) ...

For the last several years, cosmology – the study of the universe as a whole – has been facing a major tension. The two main ...

(via Sabine Hossenfelder) In the Big Bang Theory, the cosmic microwave background — microwave-range radiation that floats through the entire universe at a steady 2.7 Kelvin — is evidence that a hot ...

Gravity, as most people understand it, is the familiar force that pulls a falling apple toward Earth. But for astronomers and ...

Generally speaking, black holes are regions of spacetime where matter is compressed into a tiny space. Dark matter, meanwhile ...

Cosmological expansion is widely treated as a proven fact. It is not proven. For nearly a century, cosmology has told a ...

Black holes that formed before the Big Bang could still exist today as ‘cosmic fossils’, potentially helping to explain the ...

The clearest pictures yet of the newborn cosmos strengthen the prevailing model of the universe but deepen a mystery about its expansion rate. Measurements of this rate, known as the Hubble constant, ...

Scientists are reeling from an unexpected blow after news that a much anticipated future observatory—designed to decipher the earliest moments of cosmic history—won’t be able to proceed with its ...