The cosmological entropy is at the heart of modern astrophysical research, promoting a deeper understanding of the growing disorder that structures the Universe. For over a century, this notion, intimately linked to the second law of thermodynamics, has prompted physicists to ponder the ultimate fate of the cosmos. Today, advances in quantum cosmology, particularly through … Read more
Modern cosmology is experiencing a fascinating epoch where the foundations of our understanding of the universe are constantly being questioned. At the heart of the debates are the alternative cosmological models, which propose different and sometimes radical views compared to the standard model based on the Big Bang theory. In 2025, the quest to decipher … Read more
Very high energy gamma rays play a crucial role in understanding the most extreme and violent astrophysical phenomena in the Universe. This electromagnetic radiation, the most energetic known, is emitted by cosmic objects such as pulsars, supernova remnants, and relativistic jets. Recent studies conducted from observatories like HAWC or large ground-based telescopes now allow us … Read more
In the vastness of the observable universe, a paradox arises for physicists: why does matter dominate antimatter when the fundamental laws of physics seem to favor an almost perfect symmetry between the two? This cosmic imbalance, called matter-antimatter asymmetry, has intrigued particle physics specialists for decades. At the heart of this enigma, CP violation appears … Read more
In the ever-expanding universe, galactic halos stand out as fascinating structures enveloping our familiar galaxies. These vast spherical regions are primarily composed of dark matter, an invisible substance that cannot be directly detected but whose gravitational influence is crucial for understanding modern cosmology. The study of galactic halos allows us to decipher the large-scale organization … Read more
The cosmic microwave background (CMB) presents itself as an almost perfect and captivating imprint of what the Universe was like in its early moments, a true echo of the Big Bang enveloping the cosmos. This incessant radiation, invisible to the naked eye, has traversed nearly 14 billion years of expansion to provide us with crucial … Read more
Since the discovery of pulsars, these rapidly rotating neutron stars that emit periodic radio impulses, humanity has found in these celestial objects one of the most fascinating astrophysical phenomena. Among them, millisecond pulsars stand out for their unique ability to combine extreme rapid rotation and unparalleled temporal precision, rivaling even the most sophisticated atomic clocks … Read more
The Drake equation, formulated in 1961 by astronomer Frank Drake, remains an essential pillar in the field of astrophysics and astrobiology. This mathematical tool aims to quantify the number of potentially communicative advanced civilizations within our galaxy. From its inception, this sophisticated relationship has paved the way for a rigorous scientific approach to the search … Read more
In the vast universe, the rotation of galaxies continues to fascinate astronomers who seek to understand the mechanisms behind this fundamental movement. The orientation of galaxies, often perceived as random, actually reveals a more subtle organization. The alignment of galactic spins – the preferred direction in which galaxies rotate – has become a key area … Read more
In the vast field of cosmology, topological defects emerge as silent witnesses of the first fractions of seconds of the primordial universe. These unique structures, often stable, would have formed during cosmic phase transitions, crucial moments when the universe saw its fundamental symmetries break. These breaks left behind singular configurations of matter and energy, which, … Read more