ICRANet Scientific Report 2008 Print E-mail

Icranet

The 2008 Scientific Report

Presented to

The Scientific Committee

by

Remo Ruffini

Director of ICRANet

ICRANet was created by a decision of the Italian Government, ratified 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. After almost two years, the entrance of Brazil has been unanimously ratified by the Brazilian government. On October 24th 2007 the entrance of Brazil into ICRANet was finally signed by the President of Brazila Luiz Ignácio Lula Da Silva (details here). During the last year, we have:

  1. adjourned and recruited the Scientific Staff of ICRANet, including the Faculty, Lecturers, Research Scientists, visiting Scientists; adjourned and recruited the Administrative Staff of ICRANet;
  2. followed the procedure of the ratification of the Seat Agreement for the ICRANet Center in Pescara; started the procedure, by the letter of the Italian Prime Minister Silvio Berlusconi, for the legal status of International Organization of ICRANet in France;
  3. completed the work of restructuring and acquiring new spaces in the building of Pescara;
  4. started the restructuring of the Seat of ICRANet in Nice: Villa Ratti;
  5. promoted the entrance of additional Members in ICRANet (Hungary and New Zealand);
  6. activated the signed co-operation agreements with Universities and Research Centers, and drafted a new agreement with the State University of Rio de Janeiro (Universidade do Estado do Rio de Janeiro, UERJ) in Brazil;
  7. recruited new students, organized the teaching programs and the Thesis works of the International Relativistic Astrophysics (IRAP) Doctoral program, jointly sponsored by ICRANet and ICRA; delivered the first official diploma;
  8. organized and/or co-sponsored international meetings in Brazil, France, Italy, Taiwan and Vatican;
  9. fostered the lines of research and publication activities which are the objects of the present report.  

1) The ICRANet Staff

 In the establishment of the ICRANet Scientific Staff we have followed the previously adopted successful strategy:

  1. To appoint talented young scientists, as well as senior scientists who have already contributed significantly to those areas which led to the establishment of ICRANet.
  2. To create an adjunct Faculty containing many renowned scientists who have made internationally recognized contributions to the field of relativistic astrophysics and whose research interests are closely related to those of ICRANet. These scientists spend from one to six months at the Pescara Center, thereby linking it with their home institutions.
  3. To develop a program of Lecturers, Research Scientists, Short Term and Long Term Visiting Scientists, necessary to the scientific operations of the Center. 

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.

PROFESSORS OF THE FACULTY

As it is clear from the Accompanying Document “The ICRANet Staff, Visiting Scientists and Graduate Students at the Pescara Center”, where all the Curricula are given, the ICRANet Faculty has not been modified:

ADJUNCT PROFESSORS OF THE FACULTY

The list of adjunct Professors has been adjourned and modified by new appointments:

  • In view of the very successful lectures delivered by Prof. Gerard ’t Hooft at the 3rd Stueckelberg Meeting in July 2008 in Pescara, an offer has been made for him to join our Adjunct Faculty.
  • The “Bernard Rieman ICRANet Chair” has been appointed to Prof. Demetrios Christodoulou, who has collaborated with Remo Ruffini at Princeton, and whose activities on space-time structure and relativistic hydrodynamics are well represented in the recent texts “The Formation of Black Holes in General Relativity” (2008) and “The Formation of Shocks in 3-Dimensional Fluids” (European Mathematical Society, 2008).
  • Professor Felix Aharonian has been appointed of the Benjamin Jegischewitsch Markarjan ICRANet Chair. The work by Prof. Aharonian is well known internationally (see e.g. his book “Very high energy cosmic gamma radiation”, World Scientific, 2004). In addition to his activities at the Dublin Institute for Advanced Studies and at the Max-Planck-Institut für Kernphysik in Heidelberg, the activities of Prof. Aharonian are going to be of great importance in fostering activities with Armenia.
  • Professor Lev Titarchuk has been appointed of the Victor Sobolev ICRANet Chair. His work on accretion of Neutron Stars and Black Holes, already established within ICRANet (see the Scientific Report below), has reached great generality and assumes for ICRANet an important new role by his starting of collaborations with optical observations from the Byurakan Observatory in Armenia.

The list of the Adjunct Professors of the Faculty reads as follows:

  • Aharonian Felix Albert (Dublin Institute for Advanced Studies, Dublin, Ireland Max-Planck-Institut für Kernphysis,  Heidelberg, Germany
  • Arnett David (Subramanyan Chandrasektar- ICRANet Chair, University of Arizona, Tucson, USA
  • Chechetkin Valeri (Keldysh Institute for Applied mathematics,  Moscow, Russia)
  • Christodoulou Demetrios (Bernard Rieman ICRANet Chair, ETH, Zurich, Switzerland)
  • Coppi Bruno (Massachusetts Institute of Technology, USA
  • Damour Thibault (Joseph-Louis Lagrange- ICRANet Chair, IHES, Bures sur Yvette, France)
  • Della Valle Massimo (Osservatorio di CapodiMonte, Italy)
  • Everitt Francis (William Fairbank-ICRANet Chair, Stanford University, USA)
  • Fang Li-Zhi (Xu-Guangqi-ICRANet Chair, University of Arizona, USA)
  • Greiner Walter (Frankfurt Institute for Advanced Studies, Germany)
  • Jantzen Robert (AbrahamTaub-ICRANet Chair, Villanova University USA)
  • Kleinert Hagen (Richard Feynmann-ICRANet Chair, Freie Universität Berlin, Germany
  • Kerr Roy (Yevgeny Mikhajlovic Lifshitz-ICRANet Chair, University of Canterbury, New Zealand)
  • Misner Charles (University of Maryland, USA)
  • Novello Mario (Cesare Lattes-ICRANet Chair, CBPF Rio de Janeiro, Brazil
  • Panagia Nino (ESA, Space Telescope Science Institute, USA)
  • Pian Elena (INAF – Osservatorio Astronomico Trieste, Italy)
  • Popov Vladimir (ITEP, Russia)
  • Punsly Brian Mathew (California University, Los Angeles USA)
  • Rosquist Kjell (Karl Gustav Jacobi-ICRANet Chair, Stockholm University, Sweden)
  • ’t Hooft Gerard (Nobel Laureate, Institute for Theoretical Physics Utrecht Universiteit, Holland
  • Titarchuk Lev (Victor Sobolev ICRANet Chair, US Naval Laboratory,  University of Ferrara, Italy

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. Much of the success of the ongoing scientific sees their direct participation, as it will be clear in the scientific reports illustrated below.

SHORT-TERM VISITING SCIENTISTS

In the following we list the intense program of visiting scientists. This includes the visit of some outstanding experts who have been the focal center of scientific activity on some of our scientific meetings during one year: e.g. Prof. Abhay Ashtekar (2006 Stueckelberg Lecturer) and Prof. Thomas Thiemann (2007 Stueckelberg Lecturer).

  • Alekseev Georgy (Steklov Mathematical Institute, Russian Academy of Sciences, Russia)
  • Ashtekar Abhay (Institute for Gravitational Physics and Geometry, Penn State University Park, USA)
  • Chardin Gabriel (CNRS, Université d’Orsay)
  • Cirilo-Lombardo Diego (Bogoliubov Lab. of Theoretical Physics, JINR-Dubna)
  • Folomeev Vladimir (National Academy of Sciences of the Kyrgyz Republic)
  • Fraschetti Federico (CEA Saclay, France)
  • Gurovich Victor (Technion, Israel)
  • Pelster Axel (Freie Universitat, Berlin)
  • Thieman Thomas (Max Plank Institut fuer gravitationnsphysik Einstein Institut, Germany)

LONG-TERM VISITING SCIENTISTS

Finally, a special attention is given to scientists originating from Countries in which the field of relativistic astrophysics is having strong signs of important new developments and we are helping them in starting to participate to international researches: e.g., scientists from Colombia, Kazakistan, Kirghizistan, Korea, Libya, Vietnam, Uzbekistan.

  • Aksenov Alexey (Institute for Theoretical and Experimental Physics, Moscow, Russia)
  • Arkhangekskaja Irene (Moscow Engineering Physics Institute, Russia)
  • Boshkayev, Kuantay (Al-Farabi Kazakh National University, Kazakhstan)
  • Fimin Nicolaj (Keldysh Institute for Applied Mathematics, Moscow)
  • Hoang Ngoc-Long (IPE, Hanoi, Vietnam)
  • Kim Jik Su (Pyongyang Astronomical Observatory Kim Il Sung University, Korea)
  • Lee Hyung Won (School of Computer Aided Sciences, Inje University)
  • Mohamed Gadri (University of Tripoli, Libya)
  • Mosquera Cuesta Hermann (CBPF, Brasil and ICRANet)
  • Ri Chang Hyok (Pyongyang Astronomical Observatory Kim Il Sung University,Korea)
  • Sepulveda Alonso (Universidad de Antioquia, Colombia)
  • Song Doo Jong (National Institute of Astronomy Korea)
  • Torres Sergio (Centro Internacional de Fisica, Bogotà, Colombia)
  • Wiltshire David (University of Canterbury, New Zealand)
  • Zalaletdinov Roustam (Dept. of Theoretical Physisc, Institute of Nuclear Physics Uzbek Academy of Sciences, Uzbekistan)

ADMINISTRATIVE STAFF

The administrative and secretarial staff of the Center is

2) The Seat Agreement

The Seat Agreement on the ICRANet Center in Pescara has been signed on November 12th 2007 by the Director of ICRANet and the Director General for Cultural Affairs at the Italian Foreign Ministry (see Enclosure 2a and 2b). It is waiting for final ratification by the Italian Parliament.The Italian Prime Minister Silvio Berlusconi has recently sent a special note to the Foreign Minister of France Monsieur Bernard Kouchner with reference to the recognition of the international status of ICRANet in French territories (see Enclosure 3). This action is crucial to make full operative the ICRANet Seat in Nice. 

3) Restructuring and securing the ICRANet building in Pescara

In the recent past, the cellars underlying the Center had been submitted to vandalisms, leading in three cases to fire hazards. These cellars were practically not usable and origin of danger for the Center’s activity. For this reason, 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: a very impressive sequence of arches characterizing this ancient, unexpected, and still unexplained structure. These works have been completed on November 10th 2008. The acquired spaces are dedicated 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. Pictures illustrating the new structures are given in Enclosure 4.

4) Restructuring the Seat in Nice: Villa Ratti

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 an extremely 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 (see Enclosure 5). The works have started on November 11th 2008.

5) New members of ICRANet

Special attention has been given to the entrance of new Members in ICRANet. The Director has been pursuing the preliminary steps toward the adhesion of New Zealand to ICRANet, in order to foster the formation of a research group around Prof. Roy Kerr and establish direct contacts with the scientists in the southern hemisphere. Following the indications of the Italian Foreign Ministry, the Director had a meeting with the Hungarian Ambassador in Rome H.E. Miklos Merényi and the good news has been reached of the interest of Hungary in joining ICRANet. Discussions started.

6) Agreements with Universities and Research Centers

In addition to the previous agreements already signed with Universities in Italy and France, an Agreement with the State University of Rio de Janeiro (Universidade do Estado do Rio de Janeiro, UERJ) has been submitted for signature (see Enclosure 6). These collaborations are crucial in order to give to ICRANet scientists the possibility to give courses and lectures in the Universities and, vice versa, to provide to the Faculty of these Universities the opportunity to spend research periods in ICRANet institutions.

7) The International Relativistic Astrophysics Ph.D. (IRAP-PhD) program

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:

Third Cycle    2004-07

Fourth Cycle  2005-08

Fifth Cycle     2006-09

Cycle    2007-2010

Seventh Cycle 2008-2011

  • Belvedere Riccardo (Italy)
  • Ferrara Walter (Italy)
  • Han Wenbiao (China)
  • Lops Caterina (Italy)
  • Luongo Orlando (Italy)
  • Martinelli Matteo (Italy)
  • Pandolfi Stefania (Italy)
  • Vidotto Francesca (Italy)
  • Taj Safia (Pakistan)

We enclose the Posters of the IRAP-PhD for all the above cycles (see Enclosure 7). On November 21st 2008 is planned the first distribution of the Ph.D. Diplomas in a solemn ceremony at the University of Nice Sophia Antipolis by the President of the University and Prof. Riccardo Giacconi. Prof. Riccardo Giacconi, President of ICRANet Scientific committee, will deliver a Lecture in that occasion.

8) International Meetings

In addition to the above teaching and research activities, a maximum effort has been made by ICRANet in promoting international meetings:

In addition, we have sponsored:

Similar activity is expected to be further extended in forthcoming years:

  • The 12th Marcel Grossmann Meeting to be held in Paris from July 12th to July 18, 2009. This meeting will occur as one of the high points of the celebration of the 2009 Year of the Astronomy, recently announced by UNESCO under the proposal of the Italian government (see Enclosure 8).
  • The First Galileo-Xu Guangqi Meeting to be held in Shanghai, China, from October 26th to October 30th, 2009
  • The Sobral Meeting to be held in Fortaleza and Sobral, Brazil, from May 26th to May 29th, 2009
  • The International Conference in Honor of Ya. B. Zeldovich 95th Anniversary to be held in Minsk, Belarus, from April 20th to April 23rd, 2009 (see Encloure 8).
  • The 6th Sino-Italia Workshop to be held in Pescara from June 25th to July 3rd, 2009.
  • The 11th Italo-Korean Meeting to be held in Korea in October 2009.
  • Two meetings celebrating the United Nations Year of Astronomy 2009 in Armenia and New Zealand.

9) Lines of research

We turn now to the research activity of ICRANet, which statutory address the developments of research in Astrophysics in the theoretical framework assigned by Albert Einstein in the 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. I hereby enclose (see page 1) a recent text of mine which is being printed in these days in the festschrift book of Roy Kerr. 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.In this pursuit we are supported by three major scientific components (see Fig. 1):

 

figure1
Figure 1

 

  1. The knowledge made possible by general relativity and especially by the Kerr solution and its electrodynamical generalization in the Kerr-Newman black hole. This allows for the first time to have a theoretical framework in which to formulate the equations of motion of the gravitational collapse.
  2. The great knowledge gained in relativistic quantum field theories originating from particle accelerators, colliders and nuclear reactors from laboratories distributed worldwide. Both the developments of general relativity mentioned above and the understanding of quantum field theory give us an unprecedented tool to interpret the signal originating in the “moment of gravitational collapse” leading to the birth of a black hole, gaining information on that vast “terra incognita” in ultrarelativistic regimes never explored.
  3. The splendid facilities orbiting in space, from the Chandra to the XMM, to the Swift and Fermi missions as well as many other satellites, the VLT and Keck telescopes on the ground, as well as the radio telescope arrays offer us the possibility, for the first time, of the observations of the most transient and energetic sources in the universe: the Gamma-Ray Bursts (GRBs). These sources involves energies up to 1054 ergs emitted on a very short time scale on the order of a few seconds followed by a tail decreasing both in intensity and in energy.

Starting from these premises, an expanding frontier of knowledge is occurring in relativity, in quantum field theory, in astroparticle physics and in astrophysics. ICRANet is devoted a special effort to this program of research in its Pescara Center, also in collaboration with ICRA in Rome and the other Member Institutions. The synergy created by the theoretical developments and astrophysical observations recalled above have stimulated novel and important results in a vast range of theoretical topics (see Fig. 2).

 

figure2

 

Figure 2 

Kerr-Newman Black Holes: During these years we had the fortunate opportunity of the presence in Pescara of Prof. Roy Kerr and to discuss with him the fundamental issues of the uniqueness of the Kerr-Newman Black Hole. This issue has led to an important new result which is described in section 10, “The Kerr-Schild Ansatz Reprised”, of the report on page 79, led by Prof. Roy Kerr in collaboration with Dr. A. Geralico and Dr. D. Bini. Particular attention has also been given to the exact two-body solutions for Reissner-Nordström Black Holes. This topic has represented very important conceptual developments in the exact solutions of the Einstein-Maxwell system, and it has given explicit form for the equilibrium configuration of a system formed by a black hole and a naked singularity. The details are given in the report on page 1049, led by Prof. V. Belinski. Still on this topic of the equilibrium of a naked singularity in the field of a black hole, additional results have been given in the report on page 1669, led by Dr. D. Bini. These last results have been obtained using a perturbative technique, and are compared and contrasted to the exact solutions presented in the previous report. Still in this last report, many general relativistic effects, relevant for accretion processes and equations of motion in astrophysics, have been obtained by studying the motion of particles with structure (dipolar, quadrupolar) on certain given backgrounds of interest for astrophysics (black hole, gravitational waves). These researches have been made possible by the great expertise of the group on gravitoelectromagnetism and space-time splitting techniques in general relativity. Particularly interesting is also the work by this group describing the metric of a uniformly accelerating and rotating black hole, as well as a novel interpretation of the Lifshitz-Khalatnikov parametrization of Kasner indices and re-interpreted -in a gauge invariant way- the pulsatile behavior of certain cosmological spacetimes when approaching the singularity.

Fireball vs. Fireshell: One of the major issues in determining the initial conditions to be adopted for the description of GRBs is the understanding of the ground state of the electron-positron-photon plasma giving rise to the phenomenon and of its possibility to reach an initial state of thermal equilibrium. Two different models exist in the literature, which lead to very different scenarios. A first model, proposed by Cavallo & Rees, purported that the electron-positron pairs tends to annihilate on a very short time scale, leading to an increase of the density of photons around 0.5 MeV. This led to the “Fireball” model, in which the hot gas “pushes” on the baryonic component of the fireball, much like in a traditional atomic bomb, following the Sedov-Taylor scenario. An opposite model, the one which the ICRANet group have followed, assumes that the electron-positron plasma can reach a thermal equilibrium on a very short time scale and evolves into a “Fireshell” with practically zero temperature inside and reaching ultrarelativistic velocities due to the acceleration processes of the gradual annihilation of the electron-positron pairs in the plasma. This acceleration stops when the plasma becomes transparent. The proof of the correctness of this approach is in the report on page 137 led by Prof. G. Vereshchagin.

Fireshell Transparency: The crucial issue to estimate the rate of collisions of a shell of baryons and electrons moving at an ultrarelativistic velocity (Lorentz gamma factor g~200) interacting with the Interstellar medium is the determination of the effective cross section and the identification of the leading phenomena which determines such a cross section. Usually the electrons and protons of the beams are considered to move ballistically. In a totally new approach, which has been led by Prof. G. Vereshchagin, Dr. N. Fimin and Prof. V. Chechetkin has been the analysis of the stability of such a motion. It has been proved that in a characteristic time related to the plasma oscillation the system undergoes to a sudden transition between the proton and electron components. The total energy of the slab undergoes equipartition between the protons, the electrons and the newly created electromagnetic fields. This process is not only collisionless but the total novelty is that it is also shockless. This radically new result is presented in the report on page 137 led by Prof. G. Vereshchagin and will likely affect the further theoretical studies of the processes occurring in GRBs, Active Galactic Nuclei and Supernova remnants.

Massive Nuclear Cores: 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. The consequences of this is that an electric field close to the critical value Ec = me2c3/(eh) 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 being currently analysed is how to implement the Thomas-Fermi equations within general relativity, and how to generalize to the electrodynamical case the classical Tolman-Oppenheimer-Volkov equation of equilibrium. We are using, in this process, all the knowledge and the collaboration of the two schools of Prof. W. Greiner and of Prof. V. Popov. 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. Such a problem is being currently studied. The results of this program, led by myself in close collaboration with Prof. Greiner, Prof. Popov and Prof. ’t Hooft, is presented in the report on page 281.

Breit-Wheeler: 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 to be published by Physics Reports, led by myself, Prof. G. Vereshchagin and Prof. S.-S. Xue. Such a report is presented on page 387. 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 = me2c3/(eh). 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 analysis, among the many new results, we have imposed a new limit on the transparency of high-energy sources in cosmology. The transparency limit as a function of the cosmological redshift offer high-energy cosmological sources due to the Breit-Wheeler process. These results will be presented together with the report by Prof. H. Kleinert on page 1463.

The canonical GRB: The research on GRBs in ICRANet is extremely wide (see report on page 699) and has been participated by many Members of the Faculty, of the Adjunct Faculty, as well as Lecturers and Research Scientists. The aim is this report has been only to highlight some new results obtained on some prototypical sources and the general conclusions we are reaching on understanding the general properties of GRBs. Traditionally, GRBs are divided into two classes, “short” GRBs and “long” GRBs, arranged in a bimodal distribution with a separation around a duration of 2 s. 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. A 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. As we will see in the next presentation, they coincide with the P-GRBs and, consequently, their time scale is intrinsic to the characteristic of the source. Prof. C.L. Bianco will present these results (see report on page 699).

GRBs without supernova: A source which has represented the strongest challenge to the traditionally accepted GRB scenario is GRB 0606014, observed by Swift and VLT. 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. We also advance the possibility that the short GRBs coincide with the P-GRBs of this new class of sources whose prototypes are GRB 060614 and GRB 970228, The presentation will be given by Dr. L. Caito (see report on page 699).

P-GRB dominated GRBs: One of the most cogent issues on the GRB structure is if it may exists any P-GRB dominated GRB, namely a GRB in which the emission from the P-GRB is the predominant one. The reason is that all the GRBs we have fitted since now have a baryon loading larger than the critical value which distinguish the afterglow-dominated GRBs from the P-GRB dominated ones. The best candidate for this is GRB 050509B. We present the preliminary results of two different analyses, and we conclude that GRB 050509B may well be a P-GRB dominated GRB, with a very high peak energy (about 817 keV). The new missions Fermi-GLAST and AGILE will be important in determining the existence of this possible GRB class. The presentation is given by a graduate student from Brazil, G. De Barros (see report on page 699).

GRB X-Ray Flares: 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. From these results it appears necessary to further expand our treatment to a real 3-dimensional CBM description. Dr. M.G. Bernardini will present this topic (see report on page 699).

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 nFn spectrum peak energy Ep,i. The existence of the Amati relation has been confirmed by studying a sample of GRBs discovered by Swift. We present a theoretical interpretation of the Amati relation within our fireshell model. We construct a set of “gedanken” GRBs by scaling the fit of GRB 050315 to different values of the energy Ee±tot but keeping the same baryon loading and CBM distribution. The Amati relation is confirmed. Dr. M.G. Dainotti will present these results (see report on page 699).

Ultrarelativistic beaming: Using the exact analytic expressions for the equations of motion and the EQTS structure in the fireshell model, we present the distribution of the afterglow bolometric luminosity over the visible region of a single EQTSs. The computation is separately performed over different selected EQTSs encompassing all the afterglow regimes, from the prompt emission all the way to the latest phases. From this general treatment, one of the most interesting conclusions is that, if the luminosity is maximum along the line of sight, GRB afterglows would appear as point-like or circle-like sources in the sky, while, if it is maximum at the boundaries of the visible region, they would appear as rings. These results are presented in the report on page 995, led by Prof. C.L. Bianco.

GRBs and 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 importancy. Prof. Della Valle will make the presentation (see reports on page 699 and 1749).

In addition to these researches, still at the ICRANet Center in Pescara and at the ICRA Center in Rome, there is a large activity on the unification of fundamental interactions.

Early Cosmology and Fundamental General Relativity: In the report on page 1211, lead by Prof. Giovanni Montani, they are discussed fundamental features of the very early Universe dynamics. The presence in ICRA of Prof. Vladimir Belinski since 1991 allowed to develop a research group involved in problems concerning relativistic cosmology, especially in view of the study of chaotic cosmologies. This line of research achieved in recent years many important scientific successes, as a proper a characterization of a generic inhomogeneous Universe in the context of statistical and quantum mechanics (see “Chaos covariance of the Mixmaster model”), or the proper hydrodynamical treatment of a viscous Universe near the cosmological singularity (see “Dissipative Cosmology”). An additional line of research concerns the viability of an extended f(R) theory of General Relativity; in particular it is remarkable the result obtained for a non-analytic power-law theory which outlined weak field features which pass the Solar System test (as discussed in “Extended Theories of Gravity”).

Quantum Gravity, Quantum Fields and Unification Theories: In the report on page 1297, lead by Prof. Giovanni Montani, they are discussed different topics concerning the settings and the applications of a quantum geometrical theory. Particular attention is devoted to the role of boost invariance in a canonical quantization of the gravitational field, as well as to the implementation of extended quantization procedures to the mini-superspace. The main result obtained in this first research line is the formulation of a new action for General Relativity which outlines the local Lorenz invariance (as discussed in “Canonical Quantum Gravity without the time gauge”) in the first order approach. The second line of research faced the implementation of extended quantization procedures to describe the quantum evolution of cosmological models (see “Minisuperspace and Generalized Uncertainty Principle” and “Polymer Quantum Cosmology”). Finally, it has been performed a novel analysis of the Kaluza-Klein model, based on a phenomenological re-interpretation of multi-dimensional dynamics.

Turbulence behaviour of cosmic baryon gas: Progress on cosmology and large scale structure of the universe have been accomplished at the University of Tucson by Prof. Fang Li-Zhi and his school (see report page 1635). Particularly relevant is the work on turbulence behaviour of cosmic baryon gas. Since the pioneering work of Zel’dovich and his colleagues on 1989, it has been believed that cosmic baryon fluid should show turbulence-like behaviour in the non-linear regime. However, this feature has not been captured for a long time. It is because the turbulence of cosmic baryon fluid is the so-called Burgers’ turbulence. In order to study this behaviour, a numerical method has been developed to provide high order precision for both the smooth part of the solution and the sharp shock transitions. With the hydrodynamic simulation sample of the LCDM universe produced by the WENO (Weighted Essentially Non-Oscillatory) algorithm, Fang and his colleagues show that the intermittency of the velocity field of cosmic baryon fluid can be well described by the She-Levueque’s universal scaling formula, which is used to describe a fully developed turbulence. They found that the non-Gaussian features of the cosmic baryon fluid, governed by the Navier-Stokes equation in expanding universe, can be well described by a log-Poisson hierarchical cascade, which is a random multiplicative process (RMP) yielding the She-Levueque’s scaling. They also show that the observed samples of transmitted flux of quasar’s absorption spectrum are in good agreement with all the log-Poisson RMP’s predictions, including the hierarchical relation, the order dependence of the intermittent exponent, the moments, and the scale-scale correlation.

Determination of Black Hole Masses in Galactic Black Hole Binaries using Scaling of Spectral and Variability Characteristics: Similarly, special attention has been given in fostering the interaction with the Armenian scientists by the work of Prof. Lev Titarchuk, which are going to be further expanded with the interactions created by Prof. Felix Aharonian joining the ICRANet as Adjunct Professor. See the report by Prof. Titarchuk on page 1867.

Cosmology and Non Linear Relativistic Field Theory: The joining of Brazil to ICRANet, and the development of ICRA-BR, has registered as well the results presented in the very extensive report by Prof. M. Novello on page 1481.

Precision Attitude and Translation Control Design and Optimization: In addition 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 page 1939). Having reviewed these contributions from the ICRANet Member Institutions, we turn now to active collaborations ongoing on specific topics with other scientists and research centers. In particular, we recall the activity carried out in collaboration with the Campus Biomedico in Rome.

Interdisciplinary Complex Systems: Theoretical Physics Methods in Medicine: We recall the successful attempt of applying methodologies developed in Relativistic Astrophysics and Theoretical Physics to researches in the medicine domain. The report on page 1415, led by Prof. S. Filippi, 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. In 2008 the group has 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.

Self Gravitating Systems, Galactic Structures and Galactic Dynamics: Still in collaboration with Campus Biomedico in Rome there are ongoing researches on galactic structures. The report on page 1431, led by Prof. S. Filippi, is 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. In 2008 the group has 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 self-gravitating. This work opens the path for a new interpretation of classical Lane-Emden theory in terms of curved space-time techniques.

Relativistic Binary Systems and Gravitational Radiation: 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 1135). 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.

Magnetohydrodynamics of Black Holes: Finally, we mention 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 his report on page 1809, which is going to appear soon in the second edition of the book by Gursky and Ruffini.

Fermi and Astrophysics: 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 1937). 

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, to the Director General Gherardo La Francesca, to Cons. Barbara Bregato and to Prof. Immacolata Pannone, as well as to the Ragioneria Generale of the Italian Ministry of Treasure, for their economical support and continuous attention to our scientific activities. We are also very grateful to the Municipality of Pescara, the Municipality of Nice, and the Conseil Général des Alpes-Maritimes for their generous support in granting to ICRANet the logistics of the Centers in their respective townships. We are also very grateful to the Brazilian Institutions, currently working in the establishment of the ICRANet Seat in Brazil. 

 

 
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