Madeleine Finlay speaks to Catherine Heymans, the astronomer royal for Scotland and a professor of astrophysics at the University of Edinburgh, to understand why the expansion rate of the universe rem...

A study published in the Journal of Cosmology and Astroparticle Physics (JCAP) presents a methodology to test the assumption of cosmic homogeneity and isotropy, known as the Cosmological Principle, by...

The image of an extremely rare supernova could solve the mystery of the expansion rate of the universe.

Is it possible to understand the universe without understanding the largest structures that reside in it? In principle, not likely. In practical terms? Definitely not. Extremely large objects can dist...

Something else is influencing the expansion rate of the Universe.

Researchers from the University of Waterloo have proposed a new method to measure the Hubble constant that could help resolve one of modern cosmology's pressing puzzles: the Hubble tension.

The universe’s rapid expansion challenges current models. Scientists explore the KBC void and alternative theories to solve the mystery.

Energía oscura, tensión de Hubble y Euclid y DESI: claves para entender la expansión acelerada del universo, sin mitos, con datos recientes. El universo se expande porque el espacio-tiempo nació ya en...

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For the first time, an international research team led by the Shanghai Astronomical Observatory (SHAO) of the Chinese Academy of Sciences has demonstrated that applying pixelized strong-lensing modeling on a galaxy cluster scale can significantly improve the precision of the inferred Hubble constant (H0)—a key parameter that describes the expansion rate of the universe.

Astronomers have long known that the universe is expanding, but the exact rate of expansion, measured by the Hubble constant, remains a mystery. Multiple methods used to calculate this constant have produced conflicting results, leading to the so-called 'Hubble tension.' Researchers from the University of Illinois and the University of Chicago have developed a new technique that uses gravitational waves—ripples in spacetime caused by black hole collisions—to measure the expansion rate. This approach refines earlier gravitational wave-based methods and promises more accurate measurements as detectors improve. Their findings show that gravitational waves could provide an independent way to measure the Hubble constant, potentially resolving the tension in current estimates. This research could offer insights into the universe's age and composition, and the team hopes to apply it to future data. The method relies on a new concept called the 'stochastic siren,' which uses the background gravitational wave hum from numerous black hole mergers, not detectable individually, to estimate cosmic expansion. This technique may help narrow the range of the Hubble constant and resolve the discrepancies in current cosmological models.

Astronomers have produced one of the most precise measurements of the Hubble constant to date, but t...