Research project P6/11 (Research action P6)
To improve our understanding of Fundamental Interactions through closer collaboration between Belgian research teams engaged in theoretical or experimental approaches.
Fundamental interactions include electroweak forces, strong interactions, and gravity. Their study aims at unraveling Nature’s mechanisms at their most intimate level, including the origin of the Universe, through work at the boundary of present knowledge. The previous phase of the IAP programme, involving most of the present teams (IAP V/27), has already brought about tighter collaboration between theorists and experimentalists. This was recognized with enthusiasm by a very thorough “ex-post” evaluation, which praised the IAP’s accomplishments with an “excellent” mark on all counts.
A brief description of the theoretical and experimental groups’ activities follows.
-Some groups pursue a theoretical approach (including phenomenological models), with the aim of understanding or predicting the interactions of elementary particles. A fundamental unification of gravity and gauge theories (e.g. through strings) might be the ultimate goal. The predictions of new theories such as extra space dimensions and supersymmetry are just entering our experimental reach, and it is important to be connected to experiments in order to suggest the signatures that can be most efficiently tested.
-The experimental groups work in large international collaborations, using the most powerful accelerators and the latest observational devices to gather the data needed to test such theories or to force a new approach.
New mathematical techniques (within string and brane theory) and phenomenological modelling (in the search for a fundamental origin of masses, flavour mixings, and CP violation) are investigated. These theoretical approaches benefit from interaction with experimental groups.
We give just two examples.
After the LEP programme, which studied the vectors of fundamental interactions, the next step at CERN is the Large Hadron Collider, which will search for unification mechanisms. The prime target, the “Brout-Englert-Higgs” boson, is both the still-missing keystone of the electroweak unification and the latch for opening research into more fundamental extensions. While data taking will start in 2007 or 2008, the search strategy has to be refined well in advance. Among others, a difficult task is to extract the crucial piece of information from an enormous background. Both performing such a selection and interpreting the data necessitate the development of dedicated analysis and modelling tools. This has to start years before the actual data taking, and it requires a sustained dialogue between theorists and experimentalists.
This work benefited from our previous IAP participation, and will fully develop and bear fruit in the current phase.
A similar situation prevails in the IceCube neutrino experiment, located in the Antarctic ice to
detect high-energy signals from cosmic events.
While the "hardware" part of the experimental activities is covered by other sources of funding (FNRS, FWO, and associated funds), the IAP allows us to develop a considerable effort in the interpretation of data, which must be pursued. For this, the contribution of theory groups to help single out the key signals will be developed through the present research contract.
Postdoctoral researchers are an essential link in this research as they bring collaboration and exchange between teams. The structural lack of such postdoctoral positions is, however, a common obstacle that the previous phase of the IAP has helped solve. We paid special attention to post-doc recruiting at the international level and the IAP has increased the visibility of Belgian groups.
With the recent change in European education, the mobility of researchers is considerably increased, already at PhD student level. While this is certainly a benefit, we must expect a fraction of our PhD students to study abroad. We will compensate for this by offering foreign students the opportunity to engage in our internationally well-recognized PhD programmes.
To ensure the highest scientific quality, a central scientific board decides on all hirings supported by the programme.
Outreach is not forgotten, as we consider it a duty to keep the general public informed of this exciting field of research; it is also a way to ensure that top-level students are attracted to the field.
A new task has been added to the present application, (work package 8): a dedicated panel will be set up to consider the experimental and observational perspectives at the 2010 horizon. While two major collaborations (CMS and IceCube) will then be in full data taking, current construction tasks on these and other experiments will have mostly ended, freeing cutting-edge teams for other tasks. It is the purpose of this panel to examine a broad range of options, and advise on the best common strategy to follow to obtain key data to unravel the depths of fundamental interactions. The conclusions of this panel will be made available to the community at large.
The ultimate purpose is to improve our understanding of fundamental interactions; for this, we need
• to develop each group’s potential by additional means, mostly in personnel (post-docs);
• to tighten the collaboration and links between the activities of the groups;
• to train a significant number of young scientists with excellence in their own field and sound knowledge in the others to pursue the quest for understanding physical laws.
