Not all matter in the universe is visible. The mass of matter that cannot be “seen” by direct observatops of its emitted or absorbed electromagnetic radiation is called dark matter. In the current lambda-Cold Dark Matter (ΛCDM) paradigm, the most accepted “theory to model the Universe in large scales”, so-called baryonic (visible) matter assembles where […]
“The last star will slowly cool and fade away. With its passing, the universe will become once more a void, without light or life or meaning.” So warned the physicist Brian Cox in the recent BBC series Universe. The fading of that last star will only be the beginning of an infinitely long, dark epoch […]
They were not killed by delinquents who’d had a life of trauma, nor by sadists sunk in the abysses of sex. Their executioners were not barbarians inhabited by notions of genocides, nor slaves to sects that annul reason. They were not killed by the madness that cities sometimes engender. The horror was the handiwork – […]
No matter how elegant your theory is, experimental data will have the last word. Observations of the retrograde motion of the planets were fundamental to the Copernican revolution, in which the sun replaced Earth at the centre of the solar system. And the unusual orbit of Mercury provided a spectacular confirmation of the theory of […]
Where is the half of the ordinary matter in the universe not observed yet? Computer simulations of cosmological galaxy formation predict the existence of large intercluster filaments of hot and low-density gas, the so-called cosmic web. For the first time, ESA’s Planck satellite has observed one of such filaments in the merging cluster pair A399-A401 […]