Directed panspermia and extraterrestrial intelligence

The search for the origin of life on our planet raises fascinating questions and a sense of extraterrestrial allure that has captivated astrobiologists and astronomers for decades. The recent discovery of complex organic molecules in samples returned from the Ryugu asteroid has brought back into focus the theory of directed panspermia, a bold hypothesis suggesting … Read more

Meteorites and the Transport of Life

Meteorites, rocky fragments from celestial bodies, have long generated keen interest within the scientific community because of their potential role in the transport of life across the universe. This hypothesis, known as panspermia, proposes that living organisms, or at least complex organic molecules, may have traveled through space to contribute to the origin of life … Read more

The H0 tension in modern cosmology

In brief: Accurate measurements and discrepancies in the Hubble constant: a challenge for modern cosmology The universe expansion is a reality observed for several decades, mathematically formalized by the Hubble-Lemaître law, which describes the linear relationship between the speed of galaxies moving away and their distance, with the Hubble constant (H0) as the proportionality factor. … Read more

Large-scale correlations

As scientific disciplines explore large-scale phenomena, understanding large-scale correlations becomes an unavoidable necessity. These links between variables, discerned in massive datasets, open up unprecedented perspectives in both astrophysics and social or environmental sciences. Analyzing these complex interactions requires not only a deep mastery of statistics and mathematical models but also an ability to interpret fluctuations … Read more

The alignment of galactic spins

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

Cosmic voids and their evolution

In the vastness of the universe, beyond the twinkling of galaxies, lie enormous regions practically devoid of visible matter, the cosmic voids. These areas, true depressions in the large-scale structure of the cosmos, offer a striking contrast to the dense filaments and galactic clusters that compose the cosmic web. Their characteristics, formation, and role in … Read more

Cosmic topological defects

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

Detailed primordial nucleosynthesis

Primordial nucleosynthesis, a fundamental phenomenon marking the chemical genesis of the universe, unfolded during the very first minutes following the Big Bang. It was during this intense phase that the first light atomic nuclei appeared, giving birth to elements that will constitute the fundamental building blocks of cosmic matter. This crucial step conditioned the cosmic … Read more

Cosmological background anisotropies

The cosmic microwave background, often referred to as fossil radiation, is an extraordinary witness of the primordial universe. Originating from the time when the first atoms could form, this radiation reveals the state of the Universe approximately 380,000 years after the Big Bang. However, far from being perfectly uniform, it presents small temperature variations known … Read more

The era of cosmological recombination

In the depths of the cosmos, at a time when the Universe was in a state of transformation, a crucial phenomenon changed the very shape of everything that would become our cosmic environment. This phase, known as the cosmological recombination epoch, marks a decisive turning point in the history of the primordial Universe. Several hundred … Read more