MacDirectory Magazine

INTERVIEW THE UNIVERSE REVEALED: PHYSICS AND APPLE > A CLOSER LOOK AT THE HADRON PARTICLE COLLIDER AND APPLE’S ROLE IN PHYSICS WORDS BY ALISON FRIEDOW INTERVIEW BY MARKIN ABRAS There’s big news in the science and technology world, and it has little to do with the iPad, iPhone G4 or anything related to Apple. Instead, it has to do with gluinos, photinos, squarks and winos. If these terms leave you scratching your head, it may well be time to put down your iPod and get a quick physics refresher. Just two short months ago, while Steve Jobs was busy introducing the iPad to the world, the largest particle collider ever built — the Large Hadron Particle Collider (LHC) — was making even bigger news. This epic physics machine successfully began crashing subatomic particles, protons to be precise, into one another for the first time. But why does this matter to you? The Hadron Collider, which spans an impressive 17 miles around, is, for the first time in history, creating the potential for physicists to reconstruct and study conditions in the universe that existed before the infamous Big Bang. This means that physicists may now have the opportunity to discover more about these hypothetical particles (the gluinos, photinos, squarks, and winos) that are thought to have existed in the universe prior to the Big Bang. Physicists hypothesize that particles such as these may make up the dark matter that produces the gravity that holds cosmic structures, such as galaxies, together. Researchers contend that the Big Bang created the laws of physics, as the universe cooled billions of degrees in the aftermath of the famed collision. This cooling altered the make-up of particles, but using the Hadron Collider, physicists hope to revisit these conditions, which may possibly lead them to the discovery of the identity of dark matter. The Hadron Collider is also being used for other monumental breakthroughs, such as finding the mysterious particle known as the Higgs boson, a particle thought to instill mass in other particles, but that as of yet has been “missing” or invisible to researchers. CERN, the European Organization for Nuclear Research, is responsible for creating the Hadron Collider. The organization, which is a 20-nation association, aims to discover how the universe works. CERN spent years developing the celebrated Hadron Collider and sponsors many different projects and experiments related to the machine. ATLAS (A Toroidal LHC ApparatuS) is one of the six particle detector experiments that is currently being conducted at the Large Hadron Collider in Switzerland. MacDirectory Publisher Markin Abras caught up with Beniamino Di Girolamo, a physicist with the Atlas Experiment at CERN and a Mac enthusiast, to get more information about the Large Hadron Particle Collider, and to discuss the use of Macs in the scientific world: Markin Abras > How did you first get involved with the ATLAS experiment at CERN? Beniamino Di Girolamo > That happened at the end of 1994 when I started to work on the ATLAS Tilecal hadronic calorimeter. I had started to work in high energy physics a couple of years before, in the field of scintillating fibres used for tracking systems. At that time I was based at Pisa University and INFN. My group was working on novel detectors based on scintillating fibres read out by multi- channel photomultipliers. We participated in a R&D project and my group decided to start to be active in the Tilecal detector, where wave-length shifter MacDirectory 121

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