2019 Nobel FOR PHYSICS GOES TO THE UNDERSTANDING OF THE UNIVERSE
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The 2019 Nobel Prize for Physics was awarded on October 8th “for contributions to our understanding of the evolution of the universe and Earth's place in the cosmos" with one half to James Peebles "for theoretical discoveries in physical cosmology", the other half jointly to Michel Mayor and Didier Queloz "for the discovery of an exoplanet orbiting a solar-type star." In detail, Pebbles has developed a theoretical framework on which our modern conception of the history of the universe is based, from the Big Bang to the present.
Comment by Antonio Masiero, Vice-President of the INFN
“The theoretical physicist James Peebles is one of the great architects of the theoretical construction that describes the universe from its origin to its subsequent evolution, known as the cosmological model of the hot Big Bang. Crucial, in particular, were his contributions in the prediction and description of the oldest visible memory of the big bang, the cosmic background radiation, then experimentally discovered by the nobel prizes Arno Penzias and Robert Wilson. Equally fundamental were his contributions to the introduction of a dominant component of matter in the universe completely different from ordinary matter composed of atoms. It is the "cold" dark matter, a particular new type of matter that would be the basis of the formation of the great cosmic structures (galaxies, clusters of galaxies), and therefore also of our own life. In recent years he has also studied the form of energy (which is neither matter nor radiation) which has provided 3/4 of the entire energy of the universe, dark energy, sometimes denoted by the letter lambda: from here came the big bang model called Lambda-CDM and of which Peebles is undoubtedly one of the founding fathers".
The gravitational observatories VIRGO (in operation in Italy at the European Gravitational Observatory, EGO), LIGO (two twin detectors in Louisiana and in the state of Washington, USA) and the Japanese KAGRA (in Kamioka, prefecture of Gifu) have signed a scientific collaboration agreement that covers scientific collaboration, including joint observation of gravitational waves and data sharing, for the coming years.
ExaNeSt, the precursor of an exascale computer all made in Europe, has been successfully tested. Italy is taking part in the project with INFN, the National Institute of Astrophysics (INAF) and a group of SMEs (Small and Medium Enterprises). High performance computing (HPC) is one of the fundamental pillars of global scientific and technological research and a key factor to support the digital revolution associated with big data. Making an exascale computer means producing a supercomputer capable of performing billions of billions of operations per second (exaflops) and all the software tools to use it. Europe has long been working to make this supercomputer a reality thanks to the European Horizon 2020 program through projects like ExaNeSt. In just over three years from the end of 2015, ExaNeSt built the first prototype with high computing performance and high energy efficiency: energy consumed to solve a computational problem on this new platform is 3 to 10 times lower than that required by traditional HPC platforms. A result that went far beyond expectations thanks to an innovative liquid cooling system, the implementation of a high-performance dedicated network architecture, and a new type of computational accelerators based on programmable components. A ‘computational laboratory’ of this type is a decisive platform for preserving and improving the competitive capacity at the industrial level, for enhancing security strategies and cybersecurity, and obviously for responding to the scientific research challenges over the next decade.
In September 2019, at the KAON 2019 conference in Perugia and at a seminar at CERN, in Geneva, the collaboration of the NA62 experiment at CERN, in which INFN physicists and technologists participate, presented its new results on the very rare decay of a charged kaon into a pion, a neutrino and an anti-neutrino. The results show two events recorded in the data gathered by the experiment in 2017 and add to one decay event recorded in the 2016 dataset.In addition to these events, the NA62 collaboration presented new measures, obtained with unprecedented sensitivity, of the decay of a neutral pion into particles that are invisible to the experiment, like neutrinos or not yet known particles.At the moment, the collaboration is analysing the data collected in 2018 and the experiment is getting ready for the new data-acquisition phase that will start in 2021, with an upgrade of the experimental apparatus aimed mainly at the reduction of the background, in order to perform high-precision measurements of the very rare kaon decay. The aim is to discover any anomalies in this process, to find behaviours that the Standard Model does not predict. The rare processes represent, in fact, a privileged access channel to what physicists define as New Physics, the physics that we do not yet know and that goes beyond our current theories.The results obtained so far on over 2000 billion kaon decays are in line with the predictions of the Standard Model. However, by analyzing ever larger and ever more sensitive samples of data, divergences could emerge. The NA62 collaboration, led by the Italian Cristina Lazzeroni of the University of Birmingham, involves around 200 physicists in Europe, the United States, Canada, Mexico, and Russia, and INFN’s commitment to the project stands out. Around one third of the participants are INFN researchers: more than 70 physicists and technologists contribute in a decisive way to the success of the experiment with important responsibilities both for the detector and for the experiment’s complex data acquisition system
