EXTREME. In search of particles

A permanent exhibition to discover the tools
and work of those who explore the infinitely small

"EXTREME. In search of particles" is a permanent exhibition designed and produced by Museum in partnership with CERN - European Organization for Nuclear Research, and INFN - National Institute of Nuclear Physics.
The exhibition allows us to catch a glimpse of a fascinating research area, which explores the texture of matter in its most minute components.

In this search of the fundamental building blocks of our universe, thousands of scientists from dozens of nationalities converge around extremely large structures and ever more powerful machines. What do these researchers do? What equipment do they use? What will they explore in the near future? Are elementary particles "used" only in these large laboratories?

The exhibition sheds light on what happens in the laboratories of two of the largest research centres for particle physics. Visitors find small and large scale objects with a clear historical value, along with multimedia and interactive installations.


The narrative of the exhibition starts with the presentation of a research method that is common in many scientific disciplines: the observation and study of traces, which help us recognize and reconstruct a specific event. We use traces because they are what is left once the event has already taken place, or when the event was very fast, impossible to detect with the available instruments, or rare and hidden. Behind the introductory wall, there is a video installation on the theme of traces. The installation presents the research method used to investigate elementary articles and shows the parallelism with other scientific fields (zoology, pathology investigation, climate change, study of fossils, study of solar activity, geology, etc). Images are coupled with short sentences that help identify the revealed traces. Facing this video installation is a second installation, also created by N!03 studio but with an holographic technique, showing the recon- struction of an event (a collision between particles) obtained thanks to the study of the traces left by the particles themselves.

In this area visitors meet the protagonists of particle research: detectors. A picturesque display frames a number of historical and contemporary objects connected to important phases of Italian and international physics research. A prototype of a section of the UA1 (the experiment through which Carlo Rubbia and Simon van der Meer received the Nobel Prize in 1984), the vertex detector of the Delphi experiment (operating between 1989 and 2000 at LEP - LHC’s predecessor), a historical cloud chamber used in the Department of Physics of the University of Milan in the 1950s, components of detectors used in experiments carried out today by CERN and INFN, such as the photomultiplier for the Borexino experiment at INFN laboratories in Gran Sasso. Each displayed object is accompanied by a caption that explains its function and, in some cases, by a more extensive story told through images and documents. In parallel, the story of some of the major experiments now in progress at CERN (ATLAS, CMS, LHCb, ALICE) and at the Gran Sasso National Laboratories (DARKSIDE, BOREXINO, CUORE) lets you know the detectors currently in use, their sizes and the investigations in which they are involved.

Amid the devices and images from laboratories, is the sculpture “Atlas Remeshed” by David Angheleddu. “Atlas Remeshed” is an artist’s view of the famous “Atlas Experiment” conducted in the LCH accelerator at CERN in 2012, which made it possible for us to experimentally confirm the existence of the subatomic particle called the Higgs boson, theorized in 1964. The actual experimental data were interpreted in order to provide a fixing of this historical event. By means of four blue trajectories, the sculpture represents the so-called signature of the Higgs boson, meaning the tracks of the two muons and the two electrons generated from the collision between two protons.The other tracks, not significant for the experiment, are represented by a volume obtained through a computer graphics process called “Remeshing”, which produces a visual representation of the proximity relationships among the described trajectories. It is by means of this choice of interpretation, which creates a contrast between the sharpness of the four trajectories and the extension of the geometric shape, that we may easily grasp the signature of the Higgs boson. The work was created digitally and printed with a 3D printer. From this model the enlarged object on display has been created, using a specially developed sculpture procedure and assembly.


Experiments related to particle physics must be conducted in specific places, isolated as much as possible or shielded from disturbing elements, such as cosmic rays. For this reason the devices are placed, for example, in especially created underground caves as in the Gran Sasso National Laboratories, or under water or in Space.
When the “background noise” produced by the particles not under study has been eliminated, scientists speak of cosmic silence.
Through a parallel with the visual and sound environmental noise, the exhibition invites to experience first-hand the cosmic silence, entering a colourless and completely soundproofed space created with cutting-edge panels. Next to this installation, inspiring images show “extreme” research places such as the Gran Sasso National Laboratories and Space detectors. On display is also a lead ingot , found along with other items in the wreck of a Roman ship and used for insulation in the CUORE experiment, which will be further shielded by tonnes of lead ingots from the Roman era. In fact, the ancient Roman processing of the material removed the small percentage of uranium that was present in the lead, and after 2000 years the ingots have lost much of their residual natural radioactivity. This makes them an “ultra-pure” material, idea for shielding research apparatuses.

Research also takes place in more common spaces such as offices, and in less traditional ones such as cafeterias, where researchers take the opportunity to talk with colleagues in a context where titles and seniority matter less. In this panorama, the virtual space takes on a special role: the hundreds of research institutions that work together are connected by a computer network. The World Wide Web was invented at CERN at the end of the 1980s, and it is the natural offspring of this need to exchange data and information among researchers. Through an installation based on the photographic research of Andri Pol , who documented for more than two years the daily work at CERN, the exhibition also tells about the daily life of physicists, engineers and technicians working on experiments. At the center an exhibit, part of the installation “Research Professionals”, presents five lockers. Through the direct testimony of researchers at CERN and INFN, interviewed during an oral documentation project conceived and produced by the Museum, the world of particle research can be seen with the eyes of those who live in it. An intimate look that through an iconic phrase and an object chosen by the respondents, shows the “human” dimension of this reality, while helping to retrace some historical steps and changes in paradigms. To help visitors in the interpretation, the interviews are combined with five types of professional figures: theoretical physicist, experimental physicist, engineer, computer scientist, “builder.” Italian-speaking visitors can also sit and listen to the complete interviews from which the iconic phrases have been extrapolated.


The particles Jukebox

The particles Jukebox is an installation created by Mammafotogramma from a real 1950s jukebox. Each button is associated with one of the main known particles classified in the Standard Model, the physics theory that effectively explains their characteristics and interactions. Visitors can access a control panel where each button is associated with the name of a particle, together with its mass, electric charge, and composition (displayed with a mandala type visual effect). Each button/particle activates a sequence of 2 well-known songs written in specific years/periods, providing visitors with a more direct tool to position research on subatomic particles on a familiar timeline. So here is the Higgs boson with “I get Around” by Beach Boys - 1964 and “Gangnam Style” by PSY - 2012. For each piece of music, as well as the year, title and author of the song, there is a brief accompanying text about the particle. One song is associated to the year in which the existence of the selected particle was predicted; the other song is associated with the year in which the particle was experimentally discovered.


The Extra-dimension installation - curated by INFN Communication Office and created by CamerAnebbia - allows visitors to think about a world in which the number of possible dimensions is broader than the four that we all know about. Through a projection game, visitors approach a mirror (actually a monitor) and gradually see their reflection disappear and reappear redistributed in space in the form of unrecognizable shapes. A contemporary and technological Picasso.

Dark matter

The installation Dark matter is an interactive multimedia installa- tion created by Streamcolors that suggests that the existence and behaviour of what we “see” in the Universe is actually determined by something which we do not see (dark matter). Visitors are faced with the image of a Galaxy. On a horizontal plane they can virtually design a shapeless mass of dark colour, which represents the dark matter. As visitors act on the shapeless mass, moulding it, the image of the galaxy changes in real time following a projection of how dark matter would actually react.

Creative collisions,

A serious game developed by Digital Tales, in which two players cooperate to experience what would happen if you could make everyday objects collide at speeds close to those of light. A dice, a walnut, a pen launched against each other at these speeds may create other objects with a much larger mass, such as a bicycle or a blender. If the impact is perfect, players will witness the creation of surreal objects that will quickly decay and turn again into real objects.