Projects / Programmes
Theoretical physics of nuclei, particles and fields
January 1, 2019
- December 31, 2027
| Code |
Science |
Field |
Subfield |
| 1.02.02 |
Natural sciences and mathematics |
Physics |
Theoretical physics |
| 1.07.00 |
Natural sciences and mathematics |
Computer intensive methods and applications |
|
| Code |
Science |
Field |
| P210 |
Natural sciences and mathematics |
Elementary particle physics, quantum field theory |
| Code |
Science |
Field |
| 1.03 |
Natural Sciences |
Physical sciences |
| 1.01 |
Natural Sciences |
Mathematics |
B mesons, lepton universality, leptoquarks, dark matter, Higgs boson, collider physics, Majorana neutrinos, top quark, phase transitions, unification, supersymmetry, quantum field theory on the lattice, exotic hadrons, theories beyond the Standard Model, quasilinearization, nonperturbative methods.
Data for the last 5 years (citations for the last 10 years) on
April 18, 2024;
A3 for period
2018-2022
| Database |
Linked records |
Citations |
Pure citations |
Average pure citations |
| WoS |
477 |
16,683 |
15,460 |
32.41 |
| Scopus |
526 |
18,797 |
17,447 |
33.17 |
Researchers (34)
Organisations (2)
Abstract
We will construct models, which unify all fundamental interactions, contain light leptoquarks with masses in the TeV range, and can address the observed violations of lepton universality in BaBar, Belle, and LHCb experiments. We will study the influence of light leptoquarks on processes of neutrino scattering on nucleon targets which are being investigated by the IceCube experiment in order to explain the observed excesses in the high energy neutrino spectrum. We plan to study the phenomenology of unified theory through proton decay, fermion masses and mixing angles. We will consider such and similar theories also from the theoretical point of view by searching among others the asymptotic limits at high energy and the behaviour at strong couplings.
We will develop analyses for assessing the discovery potential of new physics related to neutrino mass origin at present and future hadronic and leptonic colliders. We will investigate the prospects for Majorana neutrino detection, including careful detector simulation with a resulting sensitivity and future outlook. We will develop a reliable theoretical framework for computing bounce solutions with an arbitrary number of scalar fields and investigate the thermal behaviour of simple scenarios related to neutrino mass origin. We will determine the nature of the transition, relation to collider signals and possible cosmological observables, such the power spectra of gravitational waves.
We will develop a novel strategy to test LFU in top decays, applicable to top pair production at both hadron and lepton colliders. We will propose spin-polarization observables optimized in sensitivity to pseudoscalar Yukawa coupling between the Higgs and the top quark.
The coupled-channel scattering in the relevant channels will be investigated using quantum chromodynamics on the lattice. We will determine the properties of the hadronic resonances, which are formed in these channels. Using quantum field theory on the lattice, we will investigate various strongly-coupled theories beyond the Standard Model, where Higgs boson and dark matter are composed of new unknown fermions f. We will determine masses and decay widths of resonances f f-bar , which can decay via this new strong interaction. We will develop numerical algorithms of our quasilinearization method, “QLM”, which provides nonperturbative, iterative and quadratically convergent solution of nonlinear differential equations, with the goal of extending the applicability and improving the numerical efficiency of QLM primarily in quantum mechanics.
Significance for science
The new results from the LHC, the super flavour factory (BelleII), as well as several smaller experiments of particle and also astroparticle physics will in the coming decade most probably fundamentally deepen our understanding of the basic laws of physics and their application to the early universe. Therefore, the proposed research program, combining in a novel way the measurements of these, has a high potential impact. Finally, it shall possibly open new avenues of experimental measurements both at the LHC as well as in low energy precision and astroparticle experiments.
In fundamental particle physics we are faced with many alternative extensions of the Standard model, however each of them is merely a hypothesis. In order to systematically narrow down possible hypotheses it crucial that we devise for each hypothesis an experiment that will be able to falsify it. The models with leptoquarks we will study are, in this context, some of the sensible hypotheses and by exposing them to experimental checks in a way we have devised in this program we can either say, in what way the leptoquark scenarios should be realized, or we can conclude that leptoquarks are not an acceptable hypothesis.
Identification of New physics model responsible for the observed lepton universality violation would be a major breakthrough. Even if the scale of New Physics model is beyond the reach of LHC the sole structure of low-energy effects would immensely facilitate narrowing down the correct New Physics model and also our understanding of physical laws at the smallest scales.
Understanding the nature of neutrino mass origin is one of the remaining scientific goals after discovery of oscillations and the Higgs boson. Devising searches for new phenomena, at colliders as well as other precision based experiments, is a crucial task needed to understand the capabilities of existing searches and to develop new ones. Proposing new channels and determining their sensitivity in standard prompt as well as in elusive channels with soft and/or displaced final states remains an important challenge.
Extended Higgs sectors received renewed attention after the discovery of the Higgs boson. They may offer insights into electroweak symmetry breaking, nature of neutrino masses and their origin, connection to dark matter as well as to dynamics in the early universe. Developing reliable and robust calculations to characterize vacuum stability and phase transitions in the early universe is a formidable task for models with many scalar fields; making progress on this front can provide a boost to the theoretical, phenomenological and cosmological communities.
Both unification and supersymmetry are possible physically motivated theories beyond the standard model. By comparing the model predictions with the experimental data (fermion masses and mixing angles, proton decay) we can check the validity of different versions of such theories: supersymmetric or not, with groups SU(5), SO(10), E6, and similar. At the same time, we can check the logical and mathematical consistence of such and similar supersymmetric theories nine the limit of strong couplings, where the perturbative approach fails.
Discoveries of the exotic hadrons near thresholds indicate that their existence might critically depend on the nearby thresholds and consequently on the strong coupling between the threshold channel with other channels. If our planned lattice simulations will support or disprove this hypothesis, we will be in better position to reliably predict yet-undiscovered exotic hadrons. This will be of great value for forthcoming experiments Belle 2, LHCb, BESIII and PANDA. The proof for the existence of the exotic hadrons Z_c = c c-bar u-bar d and Z_b = b-bar b d-bar u within lattice QCD would be an important scientific achievement, which is not available at present yet. Also a more solid understanding of the coupled-channel scattering in relation to conventional hadrons is eage
Significance for the country
Basic research on fundamental constituents of nature are part of the foundations for the sociological and cultural development of any advanced modern society. Recent developments in theoretical and phenomenological understanding of matter at smallest scales provide an opportunity to participate in the cutting edge research that requires extensive knowledge of theoretical physics. This know-how transfers to all the aspects of an educated society by teaching and mentoring students and creating public awareness of such open fundamental issues.
Moreover, testing theoretical predictions and carrying out the proposed searches requires international efforts, such as the LHC at CERN, where Slovenia is now becoming a member state. The country taking part in this enterprise can actively stimulate the progress in fundamental physics (in form of funding and people resources) and at the same time profits from exchange of new knowledge between local scientists and the international community, a process that has positive impact on the quality of knowledge that is passed to next generations at universities and schools.
Researchers which are also university teachers at the Faculty of Mathematics and Physics have the opportunity to share latest research findings with major-years students. Active participation at international conferences is a good evidence on the level of science in Slovenia. Researchers of the program have the opportunity to occasionally present our work to wider public (Stefan days at IJS, Science on street) in the form of public lectures, which leads to increased interest in science and in increased scientific culture of general public.
For example, Slovenian research using chromodynamics on the lattice affirmed Slovenia among those countries who contribute original and relevant achievements in the filed of hadronic physics. In view of many interesting experimental discoveries of unusual hadrons, it is important to stay actively involved in this interesting and vivid area of science. These endeavors have lead to close connections of our researchers with forthcoming experiments, where our members are actively involved as theory coordinators in relation to experiments Belle and PANDA. Our work and achievements have inspired students and other members of the younger generation, which is of more general importance for the society. The treasury of knowledge will be widened further by extending our expertise to the lattice studies of the strongly-coupled theories beyond the Standard Model.
Most important scientific results
Interim report
Most important socioeconomically and culturally relevant results
Interim report
