For decades, Type Ia supernovae have played a pivotal role in the discovery and study of dark energy—the mysterious force responsible for the accelerating expansion of the Universe. To do so, cosmologists compare two quantities: the redshift, i.e., the photon’s wavelength stretch caused by the geometrical expansion of the Universe ; and the Supernovae brightness […]
A new study presents a methodology to test the assumption of cosmic homogeneity and isotropy, known as the Cosmological Principle, by leveraging weak gravitational lensing—a light distortion effect described by general relativity—in astronomical images collected by new observatories such as the Euclid Space Telescope. Finding evidence of anomalies in the Cosmological Principle could have profound […]
Wandering black holes, a class of black holes that are not anchored to the centres of galaxies, are a fascinating yet elusive aspect of our universe. These black holes are not formed by the typical processes that create stellar black holes, which occur when massive stars run out of fuel and collapse under their own […]
A team of researchers has successfully demonstrated nonlinear Compton scattering (NCS) between an ultra-relativistic electron beam and an ultrahigh intensity laser pulse using the 4-Petawatt laser at the Center for Relativistic Laser Science (CoReLS) within the Institute for Basic Science at Gwangju Institute of Science and Technology (GIST), Korea. The innovation is the use of […]
The term FGK star designates a star the spectrum of which makes it either an F-type star (yellow-white, a bit hotter than then Sun ), a G-type star (yellow, similar to the Sun), or a K-type star (orange, a bit cooler than the Sun). FGK stars come in a variety of sizes but segregating them […]
Supermassive black holes exist at the centre of most galaxies, and modern telescopes continue to observe them at surprisingly early times in the universe’s evolution. It’s difficult to understand how these black holes were able to grow so big so rapidly. But with the discovery of a low-mass supermassive black hole feasting on material at […]
Author: Richard Massey, Professor of extragalactic astrophysics (dark matter and cosmology), Durham University In recent decades, we’ve learnt huge amounts about the universe and its history. The rapidly developing technology of telescopes – both on Earth and in space – has been a key part of this process, and those that are due to start […]
Made famous in 1995 by NASA’s Hubble Space Telescope, the Pillars of Creation in the heart of the Eagle Nebula have captured imaginations worldwide with their arresting, ethereal beauty. Now, NASA has released a new 3D visualization of these towering celestial structures using data from NASA’s Hubble and James Webb space telescopes. This is the […]
The emergence of detector technologies with sensitivity to lower energies and improved resolution invites a shift of emphasis in particle-decay searches for massive neutral bosons: the kinematic limit of these reactions remains an unexplored realm where cosmologically-relevant particles may be waiting to be discovered. A case that illustrate this is the charged lepton flavour violating […]
early galaxy problem Author: Rajendra Gupta, Adjunct professor, Physics, L’Université d’Ottawa/University of Ottawa Early universe observations by the James Webb Space Telescope (JWST) cannot be explained by current cosmological models. These models estimate the universe to be 13.8 billion years in age, based on the big-bang expanding universe concept. My research proposes a model that […]