At the Library, we periodically set up a “themed display” showcasing books and documents from our collection that are linked to a particular theme or anniversary. For May 2026, we have chosen dark matter.

Astronomers and astrophysicists gaze at the sky, trying to understand what exists in the Universe, discovering billions of galaxies and wondering why it looks the way it does. Galaxies are not distributed randomly throughout the Universe; they follow a structure determined by the force of gravity and the presence of dark matter, a form of matter invisible to telescopes, which does not emit electromagnetic radiation and whose (presumed) existence can today only be detected indirectly, precisely through its gravitational effects.

In 1933, Fritz Zwicky first hypothesised the existence of dark matter, but it only entered the scientific debate from the 1970s onwards, thanks to observations of the Andromeda galaxy gathered by astronomers Vera C. Rubin and Kent Ford: the two scientists measured the rotational speed of stars at the galaxy’s periphery, finding a value surprisingly high compared to the predictions of Newtonian gravity. The most plausible explanation for the anomaly was to accept the existence of a form of invisible matter.

Today it is known with certainty that dark matter accounts for approximately 85% of the total mass of the universe and 27% of the mass-energy balance.Over 

Over the past few decades, theoretical physicists have proposed a wide range of models that attempt to explain it: one of the most popular models posits the existence of so-called WIMPs (weakly interacting massive particles), hypothetical particles that are relatively heavy and interact weakly and which, for various reasons, would have characteristics almost perfectly suited to constituting dark matter. Understanding the nature of dark matter will lead us to an ever-deeper and better understanding of the formation and evolution of the Universe.

SOURCE: https://www.infn.it/fisica/fisica-delluniverso/materia-oscura/

edited by Serena Musante and Roberta Scordamaglia - CAeB

The list of books that were displayed in the Thematic Showcase:

Aspetti astrofisici della materia oscura / Marco Roncadelli
Dark matter in the universe / edited by John Bahcall, Tsvi Piran, Steven Weinberg
The dark matter problem : a historical perspective / Robert H. Sanders
Sources and detection of dark matter and dark energy in the universe : proceedings of the 8 th. UCLA symposium : Marina del Rey, California 20-22 february 2008 / editor David B. Cline