Gravity: Where Do We Stand?
Total Page:16
File Type:pdf, Size:1020Kb
Gravity: Where Do We Stand? The logo of the SIGRAV School “Gravity: Where Do We Stand?” has been composed from a number of pictures from internet and the Group of Experimental Gravitation at IAPS-INAF. It is meant to symbolize various facets in gravitational physics research. Roberto Peron thanks Andrea Reale for his help in putting together the material. Roberto Peron • Monica Colpi • Vittorio Gorini Ugo Moschella Editors Gravity: Where Do We Stand? Editors Roberto Peron Vittorio Gorini Istituto di Astrofisica e Planetologia Spaziali Dipartimento di Scienza e Alta Tecnologia Istituto Nazionale di Astrofisica Università degli Studi dell’Insubria Roma Como Italy Italy Monica Colpi Ugo Moschella Dipartimento di Fisica G. Occhialini Dipartimento di Scienza e Alta Tecnologia Università degli Studi di Milano-Bicocca Università degli Studi dell’Insubria Milano Como Italy Italy ISBN 978-3-319-20223-5 ISBN 978-3-319-20224-2 (eBook) DOI 10.1007/978-3-319-20224-2 Library of Congress Control Number: 2015949236 Springer Cham Heidelberg New York Dordrecht London © Springer International Publishing Switzerland 2016 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made. Printed on acid-free paper Springer International Publishing AG Switzerland is part of Springer Science+Business Media (www.springer.com) In Memoriam Stefano Braccini (1964–2011) Stefano Braccini sadly left us in February 2011, at a time when he was working hard on the Advanced Virgo project, studying and imagining how to achieve the best possi- ble sensitivity and secure the beginning of Gravitational Wave Astronomy. Stefano graduated in Physics in 1992, with supervisors Carlo Bradaschia and Jean-Yves Vinet, with a thesis work on the effect of diffused light in the Virgo arms and in the central area. Subsequently he studied as Perfezionando at the Scuola Normale under the supervision of Adalberto Giazotto, until the discussion of his PhD thesis in 1996. During that time he dedicated himself to the development of the Seismic Superattenuator, a characteristic feature of the Virgo interferometer that allowed then unprecedented performance in the 10 and 100 Hz detection band. Following the thesis work, Stefano took the responsibility of completing the design of the full mirror suspension and following the construction of the nine Superattenuators, ensuring the coordination of the Rome and Pisa groups. He then worked on the commissioning of the interferometer, engaging a never-ending battle against noise. High-quality data were collected in 2009, demonstrating the fitness of Virgo for listening to the sky for years. This paved the way toward the second generation of interferometers whose development Stefano devoted many efforts to, and several of his thoughts are now integrated in the design. Stefano took the leadership of the Pisa Virgo group in 2007, leading with enthusiasm the efforts on the detector and on the data analysis side, with special attention to rotating neutron star signals. He also dedicated much energy to the Istituto Nazionale di Fisica Nucleare (INFN), of which he was a researcher and then senior researcher. In particular, acting as referee for astroparticle exper- iments he was rapidly appreciated for his interest and passion for many other fields of physics research. We will remember Stefano for his achievements and his scientific and human integrity, his generosity. One way he would have liked is that we work harder than ever toward the detection of gravitational waves. Francesco Fidecaro Università di Pisa, Pisa, Italy v vi In Memoriam Angioletta Coradini (1946–2011) Angioletta Coradini was an astrophysicist and a planetary scientist. Born in Rovereto on July 1st, 1946 she graduated in Physics from Rome University in 1970; she started her career as a planetary scientist during the pioneering times of lunar samples and from then on she devoted her whole life and tremendous energy to Planetary Science and, later, to Solar System Space science and exploration. The range of her scientific interests and activities in Planetary Sciences was broad and spanned from her early study in the sta- tistical classification of lunar samples to theoretical problems in the field of Solar System formation and evolution; such as mod- elling of processes of grain accretion for planetesimals growth in gaseous disks, formation of giant planets and their satellites, and models of the thermal evolution of solid bodies in the Solar System. She published more than 200 scientific papers, many of them reference works in their respective fields. At the end of the 1980s, her personal Space Era started, and she directed her interest and energy to the field of Space Science and instrument design: a fleet of imaging spectrometers built under her responsibility are evidence of her dedication and still are flying the empty spaces of the Solar System on board spacecraft to Mars, to Venus, to the comets, to the icy realm of Jupiter and beyond. Angioletta formed a generation of planetary scientists, inspired and led her younger colleagues with her energy and optimism, and promoted the development of a Planetary Science community in Italy from scratch with her enthusiasm and her charisma. She was a generous and warm person, always ready to forget many animated discussions with the breaking of her infectious smile. As an enthusiastic and a passionate scientist, Angioletta was deeply curious of science and of the world in general, and did not stop at the questions and puzzles posed by her field, but was always ready to be diverted and interested by something for her completely new and unknown, a new challenge to respond to, a new book to study. This is why we want to remember her in this book: the SIGRAV School at Villa Olmo delved in scientific topics far from her field, but she sponsored and promoted it with all her energy and passion. To Angioletta we devote this effort and this book. Priscilla Cerroni Istituto di Astrofisica e Planetologia Spaziali (IAPS-INAF), Roma, Italy In Memoriam vii Simeone Peron (1935–2012) Simeone Peron, here with his son Roberto Preface The SIGRAV (Italian Society of Relativity and Gravitation) Graduate School in Contemporary Relativity and Gravitational Physics has become a traditional meet- ing point in Italy for research in the field of general relativity and gravitational physics. The 2009 (VIIIth) edition of this School—Gravity: Where Do We Stand?— has been envisaged as an exploration path of gravitation, seen as a pervasive phenomenon acting at all scales, from the microscopic (the realm of a still-to- be-discovered satisfactory quantum theory of gravitation) to laboratory and Solar System experiments, up to astrophysical phenomena and cosmological scenarios. Each step of this path turns out to be full of insight, full of ideas, full of dis- coveries. This is not by chance for at least three reasons. First, as stated above, gravitation seems to play a major role in a whole range of important phenomena, from the build-up of spacetime itself (an oxymoron, we may say) to the formation and evolution of astrophysical structures, up to the very origin and evolution of the universe. Second, we have had, for almost a century, an amazing theory (general rel- ativity) whose structure, and especially consequences, we are still exploring. Third, today we have at our disposal an ever-increasing amount of experimental data, from various techniques, and we can confidently speak about precision tests. The School was attended by more than 50 students from all over the world and the lecturers, all outstanding scientists, were able to cover a substantial part of current research areas, from foundations to frontiers. The days of the School—also thanks to the beautiful venue of Villa Olmo, on Lake Como—have been nice and relaxed. As is customary for the school, after the end of this edition we started working on the preparation of the related book. This took a considerable amount of time, also due to new chapters which we have added to meet the suggestions by the book referees (whom we thank for their advice). All contributions were fully updated to the time the book went to print and we are finally able to offer the text to the attention of the reader. This is also the place to remember two persons who are not among us anymore. Stefano Braccini has been a passionate and competent lecturer, and as such con- tributed to the success of the School. The news of his untimely passing filled us with ix x Preface dismay. Angioletta Coradini, at that time Director of Istituto di Fisica dello Spazio Interplanetario (IFSI-INAF), was a passionate supporter of the School. All of us miss such a great person, as well as a first-class scientist. On paper ...Thereader can find a remembrance of them by Francesco Fidecaro and Priscilla Cerroni.