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IcranetThe 2009 Scientific ReportPresented toThe Scientific CommitteebyRemo RuffiniDirector of ICRANetICRANet was created by a decision of the Italian Government, ratified unanimously by the Italian Parliament and signed by the President of the Republic of Italy on February 10th 2005. The Republic of Armenia, the Republic of Italy, the Vatican State, ICRA, the University of Arizona and the University of Stanford were the Founding Members. All of them have ratified the Statute of ICRANet (see Enclosure 1). On September 12th 2005 the Board of Governors was established and had its first meeting. Professors Remo Ruffini and Fang Li-Zhi were appointed respectively Director and Chairman of the Board. On December 19th 2006 the Scientific Committee was established and had its first meeting in Washington DC. Prof. Riccardo Giacconi was appointed Chairman and John Mester Co-Chairman. On September 21st 2005 the Director of ICRANet signed with the Ambassador of Brazil Dante Coelho De Lima the adhesion of Brazil to ICRANet. The entrance of Brazil has been unanimously ratified by the Brazilian Parliament. On October 24th 2007 the entrance of Brazil into ICRANet was signed by the President of Brazil Luiz Ignacio Lula Da Silva (details in http://www.icranet.org/). On February 2009 the board renewed the position of Prof. Fang Li-Zhi as the Chairman of the Board. During the 2009, we have:
1) The ICRANet Staff In the establishment of the ICRANet Scientific Staff we have followed the previously adopted successful strategy:
This strategy has created an outstanding research institute with strong connections to some of the most advanced Research Centers in the world. It also promotes the vital connections between all the ICRANet Member Institutions. The Curricula of the ICRANet Staff are given in the Accompanying Document “The ICRANet Staff, Visiting Scientists and Graduate Students at the Pescara Center” PROFESSORS OF THE FACULTY
ADJUNCT PROFESSORS OF THE FACULTY Typically and Adjunct Professor spends at ICRANet a period varying from one month to six months every year and keeps ongoing collaborations for the rest of the year. Typically and Adjunct Professor spends at ICRANet a period varying from one month to six months every year and keeps ongoing collaborations for the rest of the year.
LECTURERS The Lecturers participate in the many schools and meetings organized by ICRANet, as well as in the International Relativistic Astrophysics Ph.D. program (IRAP-PhD), sponsored by ICRANet and ICRA (see below). The Lecture series span from a minimum of a few weeks to the entire year.
RESEARCH SCIENTISTS The research scientists are generally at a post-doctoral level and they are extremely active in all research topics.
SHORT-TERM VISITING SCIENTISTS They include experts who have given essential contributions in ongoing activities at ICRANet.
LONG-TERM VISITING SCIENTISTS They are scientists originating from Countries in which the field of relativistic astrophysics is having signs of new developments.
ADMINISTRATIVE STAFF The administrative and secretarial staff of the Center is:
2) The Seat Agreement (see Enclosure 2a and 2b) The Seat Agreement on the ICRANet Center in Pescara has been signed on September 9th 2009 by the Italian Government and its ratification is currently being discussed by the Italian Parliament. Particularly noteworthy is the exchange and the timing of the messages between the Director of ICRANet and the Under-Secretary of State, His Excellency On. Gianni Letta. 3) Restructuring and securing the ICRANet building in Pescara (see Enclosure 3) The cellars of the Pescara Center were practically not usable and origin of danger for the Center’s activity. We have proceeded to a drastic action of restructuring, sanitizing and putting in security the building. Much to our surprise, in this action we have encountered an unexpected architectural structure underlying the building and overreaching the structure of the building itself: an impressive sequence of arches characterizing this still unexplained structure. The acquired spaces have been dedicated this year to libraries, common discussion rooms and student office space. The work has implied a major effort from an architectural point of view. In addition to the underground office space, we have developed a small amphitheatre in the open air, dedicated to lectures, including public ones, in the summer, spring and autumn. All the area surrounding the Center, which will become extraterritorial as soon as the Seat Agreement will be signed, has been fenced and a global electronic surveillance system has been installed. 4) Restructuring the Seat in Nice: Villa Ratti (see Enclosure 4) We have been very pleased to receive the invitation by the Municipality of Nice to open ICRANet activities in France, in order to maximize our contacts with other European Countries and more generally with Countries all over the world. The appeal for the town of Nice and his splendid surroundings, the existence of a modern and efficient airport, the electronic backbones for internet communications are all important elements which add to the splendid decision of the Nice Municipality to offer the historical Villa Ratti as a seat for ICRANet in Nice. The first stone for the restructuring of the Villa has been laid down on November 23rd 2007. Since, an important finding of wall paintings of circa 1750 occurred in the Villa. They are currently being restored. A large amount of activities is being carried out in renovating the building and the park around. The Villa should be operative in the first half of 2010. See also point 9 below. 5) International Meetings (see Enclosure 5) In celebration of the 2009 Year of Astronomy, a particular intense program of meetings have been organized (see Fig. 1):
In addition, in Pescara there were held:
6) Scientific Agreements (see Enclosure 6) The following Agreements have been signed, updated and renewed by the Director (see Fig. 2):
These collaborations are crucial in order to give ICRANet scientists the possibility to give courses and lectures in the Universities and, vice versa, to provide to the Faculty of such Universities the opportunity to spend research periods in ICRANet institutions.
Figure 1
Figure 2
7) The International Relativistic Astrophysics Ph.D. (IRAP-PhD) program (see Enclosure 7) Since ICRANet is an intergovernmental research institution, not granting academic degrees, it has sponsored, with ICRA, the establishment of an international relativistic astrophysics (IRAP) Ph.D. program with leading universities of European Countries: ETH Zurich, Freie Universität Berlin, Institut Hautes Etudes Scientifiques, Observatoire de la Côte d’Azur, Université de Nice Sophia Antipolis, Università di Ferrara, Università di Roma “La Sapienza”, Université de Savoie. The students admitted and currently following courses and doing research in such a program are given in the following:
We enclose the Posters of the IRAP-PhD for all the above cycles.
Figure 3
8) The Erasmus Mundus Ph.D. program (see Enclosure 8a and 8b) One of the major success of ICRANet has been to participate in the International competition of the Erasmus Mundus Ph.D. program and the starting of this program from the 2010 (see Fig. 3). The participating institutions are:
The IRAP PHD program intends to create conditions for high level education in Astrophysics mainly in Europe to create a new generation of leading scientists in the region. No single university in Europe today has the expertise required to attain this ambitious goal by itself. For this reason we have identified universities which offers a very large complementarity expertise. Each student admitted to the Ph.D. program will be part of a team inside one of the laboratories of the consortium. Each year they will have the opportunity to visit the other laboratories of the consortium and enlighten themselves with new topics in the forefront research from world leading experts. In this way the students will come in direct contact with some of the leading scientists in the world working in General Relativity, Relativistic Astrophysics and in Quantum Field Theory. In addition to the theoretical centers, we associate experimental and observational center as well. This will provide an opportunity to the Ph.D students to obtain a complete education in theoretical relativistic astrophysics and also an experience on how to carry out a specific astrophysical mission. All the institutions participating in IRAP PhD have an extensive experience in international collaborations including visiting professors, post-doctoral researchers and training of Ph.D. students. All of our partners have enrolled Ph.D. students inside their laboratories in various aspects of astrophysics. 9) Funding by the “Conseil General des Alpes Maritimes” Following the agreement with the Municipality of Nice, ICRANet was given the use of Villa Ratti for its activities in the French territory. It has been essential the financial contribution of the “Conseil General des Alpes Maritimes” of € 500.000 for the restructuring of the building. The agreement has been signed between the Director and the President of “Conseil General des Alpes Maritimes” Eric Ciotti. In addition, to this important financial contribution, we would like to mention the great scientific but also administrative success of the Marcel Grossman Meeting in Paris: the largest one organized this year by ICRANet has been amply self-supporting and gave to ICRANet a considerable economical support. 10) Lines of research We turn now to the research activity of ICRANet, which by Statute addresses the developments of research in Astrophysics in the theoretical framework of Albert Einstein’s theories of special and general relativity. Thanks to an unprecedented developments of observational techniques from the ground, from Space, and even in underground experiments in astroparticle physics, we are today capturing signals never before conceived and received in all the history of homo sapiens. The Einstein theory of relativity, for many years relegated to the boundaries of physics and mathematics, has become today the authentic conceptual and theoretical “backbone” of this exponentially growing field of relativistic astrophysics. As a testimonial of this research topic, I enclose on page 1 of the Report a recent text which has appeared in “The Kerr spacetime”, edited by David L. Wiltshire, Matt Visser and Susan M. Scott (Cambridge University Press, 2009). In it, I trace the exciting developments, which started with the understanding on the nuclear evolutions of stars, and had then led to the discovery of neutron stars, and through the splendid work of Riccardo Giacconi and colleagues, to the first identification of a black hole in our galaxy. I also enclose (see page 79) a recent document I wrote, in the occasion of the April Minsk conference, recalling some of the crucial moments in the developments of relativistic astrophysics in Soviet Union around the historical figure of Ya.B. Zeldovich. In last year report I did recall how in this pursuit we were guided by three major scientific components (see Fig. 4):
Actually, in this year 2009, thanks to a fortunate number of events and conceptual and scientific resonances, a marked evolution of these topics have occurred. New fields of research have sprouted up from the previous ones at the ICRANet Center in Pescara, at ICRA in Rome and at the other Member Institutions. The synergy created by the theoretical developments and the new astrophysical observations have stimulated novel and important results in a vast range of theoretical topics (see Fig. 5). It is so that the Kerr-Newman Black Holes have been sprouting up in three new fields: The Kerr-Newman Black holes (L, M, Q); The solitonic equations of GR; GR solutions with L, M, Q, X. Kerr-Newman Black Holes (L, M, Q): During these years we had the opportunity of the presence in Pescara of Prof. Roy Kerr as ICRANet Adjunct Professor. We have discussed with him the fundamental issues of the uniqueness of the Kerr-Newman Black Hole. In clarifying the classical methods used by him in finding the Kerr-Newman solution there has been also a distinct progress in the collaboration started last year with Dr. Geralico and Dr. Bini. This has led to an important publication, submitted this year, by D. Bini, A. Geralico, R. Kerr, “The Kerr-Shild ansatz revised”. The original Kerr-Schild ansatz has been revised by treating the Kerr-Shild metric as an exact linear perturbation of Minkowski space-time. One of the crucial points of the original derivation by Kerr was the mathematical condition that the congruence of the Kerr-Shild form of the metric had to be geodesics and shear-free. This new derivation clarifies the explicit constraint imposed by the Einstein field equation of second and third orders and how this ansatz appears naturally as a necessary condition as a solution of the Einstein equations. The development
Figure 4
of this entire field is presented in the report “The Kerr-Newman solution” on page 101. The solitonic equations of GR: Prof. Kerr’s presence in Pescara has generated during the year 2009 a conceptual resonance between the work of Prof. Vladimir Belinski, who is an ICRANet Faculty Member, himself and two new graduated students at the University of Rome on alternative derivations of the Kerr-Newman solution by the inverse scattering method. Such an approach is based on a classical paper of 1978 by Belinski and Zacharov. This research has also seen the very effective collaboration of Prof. Alekseev. This activity was presented at the 12th Marcel Grossmann Meeting and has reached a new maturity. There is the distinct possibility that all the exact solutions of the Einstein- Maxwell field equations, which are asymptotically well behaved at infinity, can indeed be found through the solitonic method of Belinski and Zacharov. This topic is being currently vigorously pursued by Belinski, visiting the University of Inje, in Korea, and by Prof. Alekseev in Moscow. This topic is being illustrated in the report “Exact solutions of Einstein and Einstein - Maxwell equations” on page 333. GR solutions with L, M, Q, X: The third independent development, which has been also scientifically very stimulating, has been due to the presence as a visiting professor for one year from the University of Unam in Mexico of Prof. Hernando Quevedo. The unsolved problem of a physical solution in general relativity of an astrophysical object which must be characterized necessarily by four parameters, mass, charge, angular momentum and quadrupole moment, has also been debated for years and it is yet not satisfactorily solved. In 1989 Mashhoon and Quevedo mathematically and formally introduced a solution of the Einstein-Maxwell equation with an arbitrary numbers of multipoles. These solutions, however, have been until now largely unexplored in their physical and astrophysical significance due to their enormous mathematical complexity. The fortunate interaction of Quevedo with the entire group of research at ICRANet has developed in a large number of new scientific ideas on this topic, and various new lines of research have been opened. Among these, the majority of them still ongoing. There has been an important result which has been published by Bini, Geralico, Longo, Quevedo [Class. Quant. Grav., 26 (2009), 225006].
Figure 5
This result has been obtained for the special case of a Mashhooon-Quevedo solution characterized only by mass, angular momentum and quadrupole moment. It has been shown that indeed such a Mashhoon-Quevedo solution can be matched to an internal solution solved in the post-Newtonian approximation by Hartle and Thorne for a rotating star. This result opens the way to the physical interpretation of a Mashhoon-Quevedo solution. Additional work is being done in establishing the limiting radius of applicability of an external solution endowed with higher multipoles. These topics have been the objects of two invited talks by Prof. Quevedo at the MG12 meeting in Paris and two joint papers by Quevedo and Ruffini at the “1st Galileo – Xu Guangqi Meeting”. They are presented in the report “Generalizations of the Kerr-Newman solution” on page 173. In light of all the above, Prof. Hernando Quevedo has been offered the position of Adjunct Professor at ICRANet. In addition to this, the more traditional work led by Prof. Jantzen, ICRANet Adjunct Professor, and Dr. Bini “Symmetries in General Relativity”, has also obtained new significant progress as reported in their report (see page 247). Among them, we mention: 1) In the context of cosmological models, Mixmaster dynamics has been analyzed in terms of curvature oscillations, leading to characteristic spiky behaviours which has been termed as the “electrocardiogram” of the spacetime itself. This work due to Bini, Cherubini, Geralico and Jantzen is very promising in view of its possible generalizations to Gowdy spacetimes. 2) The analysis of motion of particles with structure up to the quadrupole mass moment as described by Dixon's models in black hole and gravitational wave spacetimes. This work has been done by Bini, Geralico, Cherubini, Filippi in collaboration with Ortolani (INFN, Padova) and Fortini (University of Ferrara). Motivated by reaching a deeper understanding of the coupling properties between the test-body parameters (mass, angular momentum, quadrupole moment) and those of the background metric, a large variety of genuine relativistic new effects has been considered. 3) The relativistic extension of the Poynting-Robertson (PR) effect for point radiation sources. This work has been done by Bini, Jantzen and Stella. PR effect consists in absorbing and reemitting radiation by test particles orbiting black holes with superposed radiation field, a fact that causes spiral motion and has very peculiar features when considered in the context of exact General Relativity. Similarly, the Gamma-Ray Bursts topic has been sprouting up two additional new fields: Ultra high energy sources and Supernovae. Gamma-Ray Bursts: The research on GRBs in ICRANet is wide (see report on page 1631) and has been participated by many Members of the Faculty and of the Adjunct Faculty, as well as by many Lecturers, Research Scientists and graduate students. The aim of the report has been to highlight some new results obtained on some prototypical sources and the general conclusions we are reaching in the understanding of the general properties of GRBs and summarizing in a “canonical GRB”. Traditionally, GRBs are divided into two classes, “short” GRBs and “long” GRBs, arranged in a bimodal distribution with a separation around a duration of 2s. In 2001 we proposed that both short and long GRBs are created by the same process of gravitational collapse to a black hole. The energy source is the e+e- plasma created in the process of the black hole formation. The two parameters characterizing the GRB are the total energy Ee± tot of such an e+e- plasma and its baryon loading B defined as B=MBc2/Ee± tot, where MB is the mass of the baryon loading. The e+e- plasma evolves as a self-accelerating optically thick fireshell up to when it become transparent, hence we refer to our theoretical model as the “fireshell model”. We have defined a “canonical GRB” light curve with two sharply different components. The first one is the Proper-GRB (P-GRB), which is emitted when the optically thick fireshell becomes transparent and consequently has a very well defined time scale determined by the transparency condition. The second component is the emission due to the collision between the accelerated baryonic matter and the CircumBurst Medium (CBM). This comprises what is usually called the “afterglow”. The relative energetics of the two components is a function of B. For B < 10-5 the GRB is “P-GRB dominated”, since the P-GRB is energetically dominant over the second component. The contrary is true for B larger than such a critical value. Since 2001 it has been a major point of our theoretical model that the long GRBs are simply identified with the peak of this second component. As such, they don’t have an intrinsic time scale: their duration is just a function of the instrumental noise threshold. This prediction has been strongly supported by the Swift observations. It is now clear, therefore, that the duration usually quoted as characterizing the so-called long GRB class is not related to intrinsic properties of the source but it only depends on the instrumental noise threshold. This is quite different from the case of the short GRBs. From the additional work done in 2009 we have strengthen our aim to identify different families of GRBs originating from different precursors, in particular progress has been made in the understanding of Disguised short GRBs. This family was first identified through the source GRB060614 observed by Swift and VLT, a source which has represented the strongest challenge to the traditionally accepted GRB scenario. The first remarkable peculiarity of this GRB is that it is the first nearby long duration GRB clearly not associated with a bright Type Ib/c supernova (SN). This has infringed the commonly accepted collapsar scenario. The second novelty of GRB 060614 is that it challenges the traditional separation between Long Soft GRBs and Short Hard GRBs, not definitely belonging to any of such two classes. Within the fireshell model, we classified this source as belonging to a special class of events, presenting “an occasional softer extended emission lasting tenths of seconds after an initial spikelike emission”, identified by Norris & Bonnell in 2006. The crucial point of these sources is that the time-integrated luminosity of the second component is larger than the one of the P-GRB. In this respect this source is a canonical GRB. The explanation of why its peak luminosity is smaller than the P-GRB one is given by the very small average CBM density, on the order of 10-3 particles/cm3, which has been determined by the theoretical fit. This low density is compatible with a galactic halo environment. We propose that an old binary system is the progenitor of GRB 060614 and well justify the absence of an associated SN Ib/c event. Such a binary system departed from its original location in a star forming region and spiraled out in a low density region of the galactic halo. The prototypes of this disguised short GRB class have been GRB060614 and GRB970228. In 2009 an additional source has been identified as member of this class GRB050509b and the result will be presented orally to the Scientific Committee. All these objects appear to be related to progenitors formed by binary systems of neutron stars or a neutron star and a white dwarf. It is interesting that up to now no real short GRBs has yet been identified. The ones presented in the literature are just “disguised short GRBs”. Very energetic sources. Still a new family of very energetic sources has been identified (GRB 080319B and GRB 050904); both these sources are at an energy of 1054 ergs and they offer unprecedented opportunities since one is located at z ~ 1 and the other at z ~ 6.3: the nearby source allow a most significant highquality data on very short time scale which has allowed to reach a deeper understanding of the instantaneous spectrum vs. the average one. Both of them appear to originate from a collapse of a black hole of 10 solar masses. Still members of this family appears to be GRB 090423 at z ~ 8 and GRB 060607A. A very important by-product of the study of these sources has been the one of evidencing a broadening of the spectral energy distribution within the Fireshell model for highly energetic GRBs (1053-1054 ergs). An oral presentation will be given at the meeting. Additional progress has been accomplished in 2009 in the understanding of GRB-X-ray flares and the plateau emission. GRB060607A has been covered simultaneously, since the onset, both in the X-rays and gamma rays by Swift and in the near IR by the REM telescope. This fortunate situation has allowed to interpret all the near IR data within the well known synchrotron radiation in the afterglow phase, using power-law expansions for the equations of motion. This approach has not been able to study the X- and gamma radiation. Vice versa, our model, which addresses mainly the X- and gamma radiation, has been able to fit all the earliest part of the emission process and, of course, we do not address the IR part since our procedure cannot be applied in that regime. A factor in favour of our approach is that more than 90% of the energy of the source is emitted in the X- and gamma radiation and is therefore more indicative of the nature of the source. It is certainly of great interest to compare and contrast the parameters obtained within the two theoretical approaches. This source is also very interesting, since it presents some very distinct sequence of spiky emissions which may become an ideal probe to infer the structure, the density and the size of the CBM clumps, characterising our approach. This confirms some early works we performed about the nature of flares in GRBs, indeed confirming their origin in the CBM inhomogeneities. The analysis of GRB060607A has offered an additional result: the formalization of a possible scenario to explain the origin of the X-ray plateau from a collision between different subshells within a structured fireshell. An initially faster external subshell, slowed down by the interaction with the CBM, collides with an initially slower inner subshell. The plateau phase of GRBs is supposed to originate from the instabilities developed in this collision. A novel presentation will be given to the Scientific Committee. 2009 has offered also the possibility to explore the new family of sources distinctively emitting GeV radiation as pointed out by the AGILE satellite and the Fermi mission. Some preliminary results have been obtained on GRB 080916C and GRB 090902B. The preliminary results point to a new family of sources which has the characteristics of having emission very close to the absolute upper limit for GRB sources introduced by Prof. Ruffini at the MGXII in Paris. These sources appear to have an outstanding high value of the Lorentz factor g ~ 3000. A most active topic of research is being pursued in ICRANet continuing the last year research in the proton-proton collision process. Special attention has been given to the comparison between the Fermi prediction and the data observed in all high energy accelerators: CERN, Brookheaven, etc. Also a progress occurred in 2009 in the topic GRBs as distance indicators. The very frequent detections of GRBs up to very high redshifts make them essential as cosmological indicators, complementary to supernovae Ia, which are observed only up to much smaller redshifts. One of the hottest topics on GRBs is indeed the possible existence of empirical relations between GRB observables, which may lead, if confirmed, to using GRBs as cosmological probes of models universe. The first empirical relation, discovered when analyzing the BeppoSAX so-called “long” bursts with known redshift, was the “Amati relation”. It was found that the isotropic equivalent radiated energy of the prompt emission Eiso is correlated with the cosmological rest-frame νFν spectrum peak energy Ep,i. The existence of the Amati relation has been confirmed by studying a sample of GRBs discovered by Swift. Particular attention was devoted to the study of the outliers of the Amati relation. In particular, two outliers were shown to be indeed consistent with the Amati relation when the canonical GRB scenario is properly applied and the P-GRB is excluded from the Amati relation: the case of GRB050509b and the GRB071227. An oral presentation will be given to the Scientific Committee. In the report “Relativistic effects in Physics and Astrophysics” (see page 1867) it is studied the distribution of the GRB bolometric luminosity over the EQTSs, with special attention to the prompt emission phase. We analyze as well the temporal evolution of the EQTS apparent size in the sky. We use the analytic solutions of the equations of motion of the fireshell and the corresponding analytic expressions of the EQTSs which have been presented in recent works and which are valid for both the fully radiative and the adiabatic dynamics. We find the novel result that at the beginning of the prompt emission the most luminous regions of the EQTSs are the ones closest to the line of sight. On the contrary, in the late prompt emission and in the early afterglow phases the most luminous EQTS regions are the ones closest to the boundary of the visible region. We find as well an expression for the apparent radius of the EQTS in the sky, valid in both the fully radiative and the adiabatic regimes. Such considerations are essential for the theoretical interpretation of the prompt emission phase of GRBs. Ultra high energy sources: In the report on “Magnetohydrodynamics of Black Holes” (see page 2003), it is recalled the collaboration with Brian Punsly, whose second edition of the book on Magnetohydrodynamics published by Springer just appeared with the help of ICRANet. His scientific production sponsored by ICRANet, is well summarized in this report, which is going to appear soon in the second edition of the book by Gursky and Ruffini. Similarly, special attention has been given in fostering the interaction with the Armenian scientists. The most noteworthy action has been the joining of Prof. Felix Aharonian as the new member of the Scientific Committee and his appointment as the Adjunct Professor of ICRANet. Many of the observational work done by Prof. Aharonian are crucial for the theoretical understanding of the ultra high energy sources. Prof. Aharonian is also collaborating in the IRAP PhD program and will report orally to the Scientific Committee. The work on binary X-ray sources, as recalled by Prof. Lev Titarchuk, has signed some new results which are outlined in the report “Discovery of photon index saturation in the black hole binaries” on page 1971. Prof. Titarchuk will not attend the Scientific Committee meeting being a lecturer at the meeting in Christchurch organized by ICRANet. Supernovae: There has been a very clear separatrix between our GRB model and the ones in the current literature, especially the “Collapsar” one. In such a model, all GRBs are assumed to originate from supernovae. This would explain the temporal coincidence observed in some cases between GRBs and supernova events. Within our approach, we assume that core-collapse supernovae can only lead to neutron stars, and we also assume that GRBs are exclusively generated in the collapse to a black hole. Within this framework, supernovae and GRBs do necessarily originate in a binary system composed by an evolved main sequence star and a neutron star. The concept of induced gravitational collapse leads to the temporal coincidence between the transition from the neutron star to the black hole and the concurrent transition of the late evolved star into a supernova. In support of our model, clearly, there is the case of GRB 0606014 which has been already mentioned before. In our opinion, there are two distinct kind of progenitors for GRBs. First, there are the above mentioned binary systems, which are by far the most frequent, which give origin to the less energetic GRBs and are observable only up to redshifts z < 0.5. On the other hand, we assume that the most energetic GRBs do originate from the merging of binary systems formed by two neutron stars or a neutron star and a white dwarf. The very important collaboration we have established with the observational group led by Prof. M. Della Valle has been of the utmost importance. Prof. Della Valle will make the presentation (see report on page 1929) and will also report on the discovery of the most distant GRB at z ~ 8.2. We also recall the collaboration with the IHES on the splendid mathematical procedures developed by Thibault Damour and his school in the analysis of “Relativistic binary systems and gravitational radiation” (see report on page 2065). This research is particularly important for trying to find a coincidence between electromagnetic radiation, high-energy particles, ultra high-energy cosmic rays and gravitational radiation, possible observable for existing or future detectors. Two new graduate students are being devoted to this very important study within the IRAP PhD program with special attention to the study of the physical consequences of the tidal effects in General Relativity when electrodynamical structures are present in the collapsing neutron stars. Similarly, the Relativistic Quantum Field Theory topic has been sprouting up two additional new fields: “Von Kerner Zum Sterner” and Plasma Thermalization. “Von Kerner Zum Sterner”: A multi-year study in ICRA and ICRANet has been devoted to the relativistic Thomas-Fermi equations. The early work was directed to the analysis of superheavy nuclei. In the last three years, a special attention has been given to formulate a unified approach which, on one side, describes the superheavy nuclei and, on the other, what we have called “Massive Nuclear Cores”. These last ones are systems of about 1057 nucleons, kept together in beta equilibrium and at nuclear density due to the effect of self gravity. The most surprising result has been that the analytic treatment used by Prof. Popov and his group in their classical work on superheavy nuclei can be scaled to the Massive Nuclear Core regime in presence of gravity. The consequences of this is that an electric field close to the critical value Ec = me 2c3/(e) can be found on the surface layer of such Massive Nuclear Cores. This fortunate result has triggered an enormous interest and opens what it can be considered a new approach to the electrodynamics of neutron stars. The main issue has been to implement the Thomas-Fermi equations within general relativity, and how to generalize to the electrodynamical case the equations of equilibrium. We are using, in this research, the collaboration of three Adjunct Professors. In particular, Prof. V. Popov for his classical work on this topic with Ya.B. Zeldovich. In the last Stueckelberg meeting, Prof. G. ’t Hooft has forcefully expressed the opinion that a more general structure of the electromagnetic field in the massive nuclear cores must exists, in order to transfer to the electromagnetic component the gravitational energy of the process of gravitational collapse. Particularly important exchanges occurred with Prof. D. Arnett in the occasion of the discussion of the Ph.D. Thesis of J. Rueda in Rome on December 2009. The results of this program is presented in the report “Critical fields in heavy Nuclei and massive nuclear cores” on page 429. Relativistic Quantum Field Theory: A major effort in the last four years has been made to review the electron-positron creation and annihilation processes in physics and astrophysics, in a report published in Physics Reports by Profs. R. Ruffini G. Vereshchagin and S.-S. Xue. Such a report is presented on page 619. In the report there are reviewed the conceptual developments which led Dirac to describe the system e+e- ® 2g, Breit Wheeler to describe the system 2g ® e+e- and the classical papers of Sauter, Euler, Heisenberg and Schwinger to the analysis of vacuum polarization and pair creation in an overcritical electric field Ec = me 2c3/(e). In addition three ultrarelativistic processes have been in depth reviewed. They deal with (1) the vacuum polarization process in the field of a Kerr- Newman black hole; (2) the feedback of the electron-positron pair creation on the overcritical electric field; and (3) the thermalization process of the created e+e- plasma. This reports, with more than 500 references, gives the background necessary to initiate the study of the quantum field theory description of the electrodynamical approach in the process of gravitational collapse. It is interesting that, in the preparation of this report, among a variety of new results, we have imposed a new limit on the transparency of high-energy sources in cosmology. Details are given in the report “Electron-positron pairs in physics and astrophysics” on page 559. Still in this topic, a vast application of relativistic quantum field theoretical approach to astrophysical phenomena, led by Prof. H. Kleinert, have been summarized in the report “Applied quantum field theory” on page 923, with a vast number of ongoing collaborations with scientists at ICRANet and leading institutions worldwide. The report on “Cosmology and non linear relativistic field theory” on page 949 covers the activity in this field led by Prof. Novello in the ICRANet Center in Rio de Janeiro (Brazil). The main lines of research of ICRANet developed at ICRA-BR by Prof. Mario Novello , Ceasre Lattes adjunct Professor of ICRANet, and his group during 2009 are: 1. Bouncing Cosmology, 2. Effective Geometry in non-linear Electrodynamics, including a non-gravitation Black Hole, 3. Cyclic Magnetic Universe, 4. Higgs mechanism without Higgs boson, 5. Spinor theory of Gravity, 6. The Spectrum of Scalar Fluctuations Using Quasi- Maxwellian Formalism, 7. Gravitational Waves in Singular and Bouncing FLRW Universes. The list of important publications is attached in the complete report. The participation of three graduate students from Brazil, each year, is planned in the IRAP PhD and the Erasmus Mundus program starting 2010. Still on Relativistic Quantum Field Theory there is the Report “Quantum Gravity and Unification Theories” on page 2201. The investigations on Quantum Gravity and Unification Theories were devoted to analyze the basic principles of these approaches and some specific applications in a cosmological setting. Over 2009, the topic research lines have been the following: Canonical Quantum Gravity without the time gauge; The problem of time in Quantum Gravity; Quantum suppression of weak anisotropies; Quantum behavior of the Universe for small oscillations; Regularization and Quantization of Einstein-Cartan theory; Brown-Kuchar approach in 5D Kaluza-Klein model; Test Particle Dynamics; Coupling with matter: Papapetrou approach; Geodesic deviation; Massive test particles motion in Kaluza-Klein gravity. In particular, it can be regarded as outstanding: the possibility to infer a SU(2) gauge structure for the Hamiltonian formulation of gravity, which allows to apply canonical quantization procedures in a generic local Lorentz frame; the predicted suppression of Universe anisotropies after the quantum to classical transition; the study of modified stable circular orbits surrounding a 5-dimensional Black Hole. Finally, there is the report on “Early Cosmology and Fundamental General Relativity” on page 2331. In these lines of research, general aspects of the Early Universe dynamics and Fundamental General Relativity approaches are discussed. In particular, during 2009, the activities were concentrated on the following main topics: Dissipative Cosmologies; Jeans instability of gravitational perturbations; Extended Theories of Gravity; Interaction of neutrinos and primordial GWs; Coupling between Spin and GWs; The role of Plasma Physics in Accretion disk morphology; Gravitational polarizability of black holes. It is remarkable to have outlined, on the one hand how the cosmological neutrinos can modulate the spectrum of stochastic cosmological GWs at the scale of the nHz, and on the other one how it is possible to reconcile the crystalline structure of a plasma disk with its accreting properties. Large scale structures: Such a topic has led to a variety of new results which are summarized in the report “Theoretical Astroparticle Physics” on page 1333. Astroparticle physics is a new field of research emerging at the intersection of particle physics, astrophysics and cosmology. Our group focused on several topics with two major directions of research: a) electron-positron plasma in astrophysics and b) neutrinos and large scale structure formation in cosmology. Electron-positron plasma appear relevant for GRBs, but also for the Early Universe, in laboratory experiments with ultraintense lasers etc. We study both nonequilibrium effects such as thermalization and associated timescales, as well as dynamical effects such as accelerated expansion in the optically thick regime. Relativistic numerical codes are designed and widely implemented in this research. The basic outcomes include: determination from the first principles of relaxation timescales of optically thick electronpositron plasma with baryonic loading in the wide range of plasma parameters; conclusion that deviations from a simple "frozen radial profile" in spatial distributions of energy and matter densities of expanding electron-positron plasma with baryonic loading are possible. The last conclusion imply in particular the possibility to recover the spatial distribution of matter and energy in the process of collapse of a GRB progenitor to a black hole. Neutrinos were considered as the best candidate for dark matter as the evidence for rotation curves of galaxies became manifest. The central role of massive neutrinos of a few eV was then discussed from a conceptual point of view changing from the description of the physical properties by a continuous function to a new picture introducing a selfsimilar fractal structure. This approach has been relevant, since the concept of homogeneity and isotropy formerly apply to any geometrical point in space and leads to the concept of a Universe observer-homogeneous. The role of massive neutrinos was also applied to cosmological nucleosynthesis. In the recent years, an alternative approach to the structure formation in the Universe was developed using an yet undetermined neutral particle with a mass in the keV range. The approach of the massive neutrinos is a typical top-down approach, starting from the largest structures and reaching the halos of galaxies by successive fragmentations. The keV approach, on the contrary, starts from relatively small structures in a typical bottom-up approach. Recent observations of clusters of 1015 solar masses at a redshift z=1.2 reopen this entire topic of research. The topic of large scale structure of the Universe, treated in the last part of the Report, have been further developed in the work of Prof. Einasto, presented in Paris in the occasion of his receiving the Marcel Grossmann award is summarized in the Report “Cosmology group of Tartu Observatory” on page 1525. Prof. Einasto has been appointed as a new Adjunct Professor starting from 2009. A particularly important set of contributions, critically analyzing the effect of inhomogeneity and anisotropy in a Friedmann Cosmology affecting the entire interpretation of the acceleration of the Universe, have been developed in Pescara by David Wiltshire on sabbatical from the University of Christchurch. See the Reports “Average observational quantities in the timescape cosmology” on page 1557 and “Gravitational energy as dark energy: Average observational quantities” on page 1579. The Report on “Cosmology and Large Scale Structures” on page 1589 manifests the progress made by the ICRANet group at the University of Arizona. It deals with two different topics. A. Turbulence behavior of cosmic baryon gas. With hydrodynamic simulation sample of the LCDM universe produced by the WENO algorithm, we show that the intermittency of the velocity field of cosmic baryon fluid at redshift z=0 in the scale range from the Jeans length to about 16h-1 Mpc can be extremely well described by the She- Lévĕque's scaling formula, which is used to describe a fully developed turbulence. We also found that the non-Gaussian features of the cosmic baryon fluid and Ly-a transmitted flux of quasar absorption spectrum can be well described by a log-Poisson hierarchy. B. Wouthuysen-Field coupling. With a state-of-the-art numerical method, we show that the resonant scattering of Ly-a photons with neutral hydrogen atoms will lock the color temperature of the photon spectrum around the Ly-a frequency to be equal to the kinetic temperature of hydrogen gas. The time scales of the onset of Wouthuysen-Field coupling, the profile of frequency distribution of photons in the state of local thermal equilibrium, the effects of the expansion of the universe on the Wouthuysen-Field coupling in a optical thick halos have also been found. These results are essential for studying the 21 cm signal from high redshift sources. In collaboration with Campus Biomedico in Rome there are ongoing researches on galactic structures. The Reports “Self Gravitating Systems, Galactic Structures and Galactic Dynamics” on page 2141 and “Hamiltonian Dynamical Systems and Galactic Dynamics” on page 2169 are focused on analytical and numerical methods for the study of classical self-gravitating fluid/gaseous masses. A series of papers of this group have been devoted in the past to the generalization of the classical theory of ellipsoidal figures of equilibrium using virial methods. The research activities of the group have focused subsequently on functional methods for obtaining equilibrium solutions for polytropic self-gravitating systems that rotate and have a non uniform vorticity. The group has recently published a novel and important result in the context of analogous geometry theory. It is well known that the wave equation for the perturbations of given a perfect barotropic and irrotational Newtonian fluid can be rewritten as an “effective General Relativity”. They have extended this result including the possibility for the fluid to be selfgravitating. This work opens the path for a new interpretation of classical Lane-Emden theory in terms of curved space-time techniques. We recall the successful attempt of applying methodologies developed in Relativistic Astrophysics and Theoretical Physics to researches in the medicine domain. The Report “Interdisciplinary Complex Systems” on page 2183 adopts analytical and numerical methods for the study of problems of nonlinear dynamics focusing on biological systems and using a theoretical physics approach. It is well established both numerically and experimentally that nonlinear systems involving diffusion, chemotaxis, and/or convection mechanisms can generate complicated time-dependent spiral waves, as in happens in chemical reactions, slime molds, brain and in the heart. Because this phenomenon is global in Nature and arises also in astrophysics with spiral galaxies, the goal of this research activity has been to clarify the role of this universal spiralling pattern. The group has studied numerically the nonlinear partial differential equations of the theory (Reaction-Diffusion) using finite element methods. The group has recently published a novel and important result: an electromechanical model of cardiac tissue, on which spiral moves and causes the domain to deform in space and time. This model is a real breakthrough in the context of theoretical biophysics, leading to new scenarios in the context of computational cardiology. Complementary to these physical and astrophysical large effects of general relativity, particular attention in ICRANet is given to follow and to propose the theoretical framework of high-precision tests of general relativity from space around the Earth in collaboration with the Stanford University (see Report “Fundamental Physics in Space and Required Technologies” on page 2449). A graduate student Valerio Ferroni is approaching his thesis discussion and will present an oral report at the meeting. In addition to all these scientific activities, ICRANet is very sensitive to promote publications and translations of classical textbooks in all languages. In this sense, we recall the ongoing translation into Vietnamese and Arabic of the text “Gravitation and Spacetime” by Hans Ohanian and Remo Ruffini, which has been already published in English, Italian, Korean and Chinese. Finally we recall the completion of the book “Fermi and Astrophysics” which promises to reconstruct the worldlines of Enrico Fermi in the domain of general relativity, with special attention to the period spent at “La Sapienza” (see report on page 2445). In Fig. 6 there are presented in blue the topics of selected oral presentations to the Scientific Committee on December 14th–15th, 2009. “Solitons in Einstein Maxwell Theory” will be presented by Prof. Vladimir Belinski; “e+e- plasma” by Prof. She-Sheng Xue; “Unified Theories”
Figure 6
by Dr. Giovanni Montani; “Theoretical Astroparticle Physics” by Prof. Gregory Vereshchagin; “Canonical GRBs” by Prof. Carlo Luciano Bianco; “The Amati relation” by Prof. Lorenzo Amati; “GRB Dynamics” by Dr. Gustavo De Barros; “GRB injection” by Dr. Maria Grazia Bernardini; “GRBs at z≈8” and “GRBs and Supernovae” by Prof. Massimo Della Valle; “1054 erg GRBs” by Dr. Barbara Patricelli; “Disguised short” by Dr. Letizia Caito; “UHE Astrophysics” by Prof. Felix Aharonian; “Large Scale Structure of the Universe” by Prof. Jaan Einasto; “A Novel Approach to Neutron Stars” by Dr. Jorge Rueda; “Quevedo Solution” by Prof. Donato Bini; “Astrophysics and Biomedicine” by Dr. Christian Cherubini. Acknowledgements I am very happy to express, on behalf of all the Members of ICRANet and myself, our profound gratitude to the Italian Prime Minister Silvio Berlusconi, to the Italian Foreign Minister Franco Frattini and to the Minister of Economy and Finances Giulio Tremonti. A personal sign of gratitude goes to Gianni Letta, the Under-Secretary of State to the President, for his multi-year support of ICRANet, since its first establishment. A sign of gratitude goes to Min. Plen. Francesco Maria Greco, to Min. Plen. Vincenza Lomonaco and to Prof. Immacolata Pannone as well as to the Ragioneria Generale of the Ministry of Economy and Finances, for their daily attention in the activities of ICRANet. A special recognition goes to the activities of the many Ambassadors and Consuls who have greatly helped in the intense series of activities carried out in 2009 by ICRANet in Belarus, Brazil, France, China, Korea and New Zealand. This year has been marked by the restructuring of the seat of Villa Ratti in Nice and by the completion of the seat in Pescara. We are grateful to the Mayor of Pescara, Luigi Albore-Mascia, to the Minister-Mayor of Nice, Christian Estrosi, to the Adjunct for Science, Research and Culture, Dr. Agnes Rampal, and to the President of the Conseil Général des Alpes-Maritimes, Eric Ciotti, for their generous support in granting to ICRANet the logistics of the Centers in their respective townships. We are equally very grateful to the Brazilian Institutions, the Foreign Minister of Brazil, the Minister of Science of Brazil, the Governor of the State of Cearà, the Mayor of Rio for their essential support in the establishment of the ICRANet seat in Brazil. A special sign of gratitude goes to Minister Roberto Amaral and to Prof. Francisco José Amaral Vieira for their continuous support. All this work could not have been achieved without the help of all Members institutions of ICRANet. In this Year of Astronomy we would like to acknowledge and to express our deep gratitude to UNESCO and to the Vatican Observatory for the many strategic collaborations which have made these celebrations scientifically, culturally and spiritually very successful. Clearly, a special mention of satisfaction goes to all the Scientific Institutions and Research Centers which have signed with us a collaboration agreement which include BSU (Belarusian State University, Belarus), Cearà State (Brazil), ENEA (National Agency for new technologies, energy and the economic sustainable development, Italy), ICTP (The Abdus Salam International Center for Theoretical Physics, Italy), INFN (National Institute for Nuclear Physics, Italy), LeCosPa (Leung Center for Cosmology and Particle Astrophysics, Taiwan), NAS (National Academy of Science, Armenia), Nice University Sophia Antipolis (France), Physics Department of University of Rome “Sapienza” (Italy), UERJ (Rio de Janeiro State University, Brazil). ICRANet, as sponsor of the IRAP-PhD program, expresses its gratitude to AEI – Albert Einstein Institute – Potsdam (Germany), Berlin Free University (Germany), CBPF – Brazilian Centre for Physics Research (Brazil), Ferrara University (Italy), Indian centre for space physics (India), Nice University Sophia Antipolis (France), Observatory of the Côte d'Azur (France), Rome University – “Sapienza” (Italy), Savoie University (France), Shanghai Astronomical Observatory (China), Stockholm University (Sweden), Tartu Observatory (Estonia), for their joint effort in creating this first European Ph.D. program in Relativistic Astrophysics which has obtained the official recognition of the Erasmus Mundus program of the European Community. Finally, thanks goes to the Physics Department and to the Rector of the University of Rome “Sapienza” for all the collaboration in the teaching, in the electronic links and in the common research. A special mention of gratitude, of course, goes to the administrative, secretarial and technical staff of ICRANet and ICRA for their essential and efficient daily support.
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