International PhD studies in Fundamental Problems of Quantum Gravity and Quantum Field Theory

Faculty of Physics of the Unversity of Warsaw is conducting an international PhD program "International PhD Studies in Fundamental Problems of Quantum Gravity and Quantum Field Theory" supported by the Foundation for Polish Science, International PhD Programme (MPD) co-financed by the European Union within the European Regional Development Fund.

The program offers:

 

Quantum Field Theory and General Relativity are the only widely accepted, truly fundamental theories of Nature. The former describes physics at the smallest scale, the latter deals with physics at astronomical scales and together they account for nearly every phenomenon at any scale ever observed. All the other physical theories from Newtonian mechanics to the theory of superfluidity can be eventually traced back to one (or both) of the fundamental theories. In addition, General Relativity and Quantum Electrodynamics (a model example of a Quantum Field Theory) are the two most precisely tested theories in physics. These theories are perhaps the greatest accomplishments of the twentieth century's physics.

Despite being so immensely successful and universal, the two fundamental theories suffers from fundamental difficulties. Attempts to formulate a quantum field theory in presence of gravitational field have not provided satisfactory generic results yet.

Just as the Quantum Field Theory experiences serious problems in the presence of gravity, the General Relativity (a purely classical theory) breaks down in the presence of quantum-mechanical matter. It is widely believed that the only way to solve this problem is to reformulate General Relativity in a quantum manner. An important step in this direction has already been done when the Ashtekar-Lewandowski Quantum Loop Gravity theory has been formulated. The group of prof. Jerzy Lewandowski (who is one of PhD supervisors within this project) at the University of Warsaw is one of the leading centers in this field. During the last two decades fundamental structures of this theory have been recognized and important ,,toy-models’’ constructed. Nevertheless, the theory contains many unsolved problems of fundamental importance and requires  further efforts which could, probably, lead to realistic models, describing interaction of gravity with quanta in a satisfactory way. The University of Warsaw faculty is supported by prof. Jerzy Glikman-Kowalski (University of Wrocław) who is a supervisor of one of the PhD projects.

One of the most important targets for this project is to strengthen efforts directed towards construction of quantum gravity and quantum field theory in the presence of gravity.

An application of quantum field theory to describe electromagnetic, weak and strong interactions resulted in a construction of the Standard Model (SM) of fundamental interactions, a quantum gauge field theory. The electroweak sector of the SM has been tested and confirmed at an impressive level of precision. Nevertheless, still some fundamental problems remain. Within electroweak theory the hierarchy problem triggered an intensive research focusing on extending the SM so that the Higgs boson mass is protected against large (quadratically divergent) radiative corrections. Lack of a candidate for dark matter is another drawback of the SM which provides a continuous impulse to go beyond the SM, such that the observed abundance of the dark matter is properly predicted. Also the issue of CP-violation in the context of baryon generation is still an open problem. Those issues are supposed to be investigated within this project in the course of PhD studies under supervision of  prof. Bohdan Grzadkowski from the University of Warsaw. He and his foreign partners form an experienced team which has already proposed and investigated various ideas which could eventually ameliorate the aforementioned problems. One of the most promising candidates for the extension of the SM  is provided by supersymmetric theories, in particular supersymmetric Grand Unified Theories (GUT). Within such theories, the strong, weak and electromagnetic interactions unify into a single one at very high energies. Unification constraints on fermion masses and flavour-violating Yukawa couplings are of crucial importance. Studying those constraints is the research topic of one of the projects supervised by prof. Mikołaj Misiak from the University of Warsaw. It is a part of the common effort of many researchers find the simplest supersymmetric GUT which satisfies all the existing phenomenological requirements. Recently, an interesting class of supersymmetric GUTs has been constructed and named F-GUTs (F taken from F-theory: an avatar of string theory). The models provide all necessary physical ingredients: supersymmetry breaking sector, dark matter candidates and interesting neutrino sector. The research in this direction will be supervised by prof. Jacek Pawelczyk from the University of Warsaw. The theory of strong interactions, QCD, is again a successful theory, however the very fundamental problems of quark confinement and hadronic bound states definitely require deeper understanding. Those issues will be investigated within this project applying a framework based on the similarity renormalization group procedure for Hamiltonians that was originally formulated by Głazek and Wilson and subsequently developed by Głazek and his students in the University of Warsaw in application to QCD. Prof. Stanisław Głazek is a supervisor within this project.

The foreign partners involved into this project are world-famous specialists in the Quantum Field Theory and Quantum Gravity.  Some of them are pioneers in the work covered by topics proposed in the PhD projects. Among them are laureates of prestigious awards such as J.J. Sakurai Prize, Dirac Prize and Shaw Prize. Their scientific institutes have long tradition of cooperation with researchers from all over the world and in teaching students and young researchers. They are leading centers in research areas covered by the proposed topics. They employ many renown researchers including Nobel Prize laureates. Students working within the program will get a unique training and gain experience working in multi-national teams which will be invaluable in their prospective work.