Physics

The mission of Physics is to investigate the fundamentals of our World and of our Universe and to provide an understanding of the basic principles. But there is more than fundamental research going on, apart from eclat spin-offs (see for example the invention of the World Wide Web at CERN); there are a lot of applied research activities which have, or might have, an impact on our daily lives. This complexity is somehow represented in this section in which fundamental and applied physics merge.

The contribution of J.R. Klaus represents a real projection into the future and it is also at the frontier between physics and biology. In his paper (included in the Interdisciplinary section of the Annals) he proposes an interdisciplinary approach to material science, involving biological methods to complement existing physical and chemical coating techniques.

The study presented by Ralf-Hendrik Menk indicates that the application of holographic techniques to X-ray imaging leads to superior image quality and better resolution (even down to atomic scale) with respect to standard imaging techniques. These novel techniques are expected to have an impact on all kind of X-ray imaging, from material testing to medical imaging. Objects almost transparent to standard radiography will became clearly identifiable, at a radiation dose much lower than that used to date, when adequate detection systems are developed. This is very important for all medical applications. In the field of fundamental research, X-ray holography could play a key role in the determination of complex protein structures.

Antonaldo Diaferio in "The Large Scale Distribution of Galaxies" tries to probe, with sophisticated computer simulations, our present understanding of the Universe we live in. As simulation results depend on the adopted cosmological model and on the working hypothesis, their comparison with observation gives an indication of the validity of our current knowledge of the Universe. The Universe as we know it today is not a static and uniform set of galaxies. Due to cosmic expansion, galaxies are moving apart from one another. In addition, galaxies are concentrated in clusters and super-clusters: these have formed as a consequence of initial inhomogeneities in the primitive Universe and of the distribution of the so-called "dark matter", a special kind of matter which is not observable, but accounts for about 90% of the total matter in the Universe. A detailed comparison of the simulation results with real surveys shows that the simulation of the galaxy clustering process is quite accurate. But the investigation is not over yet. Diaferio foresees a full comparison of the simulation of the evolution of galaxies with the data from the space-based Hubble telescope. More exciting results on the formation of the Universe will be coming soon.

In the era of information revolution, physics is playing a key role in providing new technologies for more rapid and more efficient storage of the ever-increasing quantity of information, which is becoming available to us. Magnetic multi-layers and spin-dependent tunnel junctions are emerging as prime candidates for information storage in magnetic recording technology (such as in computers, video and audiotapes). This is a rapidly growing industry with an estimated annual market of $1 billion. In his contribution J.M. de Teresa describes an exciting set of experiments which, for the first time, demonstrate the important role of the insulating barrier in the working of spin-dependent tunnel junctions. The active role of the barrier provides technologists with an additional way to control and improve the performance of these devices. The experiments by J.M. de Teresa also provide an explanation for a long-standing puzzle regarding the transport of electrons in such systems.

Joerg Heber, Maziar Nekovee, Marco Valentini