Exact Results in Quantum Theory & Gravity
Ścisłe rezultaty teorii kwantów i grawitacji
fall 2012
prof. dr hab. Jan Dereziński, prof. dr hab. Jerzy Lewandowski
prof. dr hab. Krzysztof Meissner
Hoża 69, room SDT, fridays 14:15 - < 16:00
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Exact Results in Quantum Theory & GravityŚcisłe rezultaty teorii kwantów i grawitacjifall 2012prof. dr hab. Jan Dereziński, prof. dr hab. Jerzy Lewandowski prof. dr hab. Krzysztof Meissner Hoża 69, room SDT, fridays 14:15 - < 16:00 |
| Date | Speaker | Title | Slides |
|---|---|---|---|
| 12.10.2012 | Marcin Napiórkowski | TBA | |
| 19.10.2012 | | ||
| 26.10.2012 | | ||
| 02.11.2012 | | ||
| 09.11.2012 | | ||
| 16.11.2012 | Igor Khavkine | TBA |
| Date | Speaker | Title | Slides |
|---|---|---|---|
| 07.10.2011 | Marcin Napiórkowski | The Excitation Spectrum for Weakly Interacting Bosons I
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| 14.10.2011 | Marcin Napiórkowski | The Excitation Spectrum for Weakly Interacting Bosons II
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| 21.10.2011 | Michał Artymowski | Inflation driven by the Higgs field
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| 28.10.2011 | Michał Dziendzikowski | Diffeomorphism covariant
representations of quantum observables
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| 04.11.2011 | Michał Wrochna | QFT in external potentials and Hadamard states
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| 11.11.2011 |
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| 18.11.2011 | Jean-Pierre Gazeau | Quantization with (pseudo)-action & angle coherent states
Abstract is available here. | |
| 25.11.2011 | Marcin Kisielowski | On Feynman diagrams for Loop Quantum Gravity
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| 02.12.2011 | Jan Dereziński | Otwarte problemy na temat równania Diraca-Coulomba |
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| 09.12.2011 | Yaser Tavakoli | Singularities in Classical and Quantum Gravity |
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| 16.12.2011 | Michał P. Heller | Warsztaty z AdS/CFT i zastosowań |
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| 11.01.2012 | Rafał Suszek | The Gauge Principle in 2d sigma-models/critical string theory I
ABSTRACT: In these lectures, I shall discuss various geometric and field-theoretic aspects of the Gauge Principle for multi-phase sigma-models with a topological (Wess-Zumino) term, as formulated by K.Gawędzki, K.Waldorf and myself in the framework of gerbe theory and generalised geometry. The focus shall be on universal structures and constructions rather than peculiarities of the 2d setting in hand. Thus, upon recalling some field-theoretic, geometric and categorial prerequisites (the world-sheet description of multi-phase CFT, the 2-category of bundle gerbes with connection, and basic theory of (Lie) groupoids and algebroids), I shall elaborate on the following issues: - a groupoidal/algebroidal description of rigid symmetries, its generalised-geometric interpretation and a nice picture of the local gauge anomaly; - rendering rigid symmetries local - the minimal coupling recipe and beyond; - the Principle of (2-)Categorial Descent, and equivariant structures (bundles, gerbes etc.); - the role of (topologically) non-trivial gauge bundles in the construction of a consistent model on the symmetry coset; - (equivariant-)cohomological classification of obstructions to gauging and inequivalent variants thereof. Time permitting, I shall also outline possible applications of the framework described in an attempt at understanding T-duality (resp. mirror symmetry) for toroidally fibred target spaces, and the (non-)geometry of T-folds. | |
| 13.01.2012 | Rafał Suszek | The Gauge Principle in 2d sigma-models/critical string theory II
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| 20.01.2012 | Magdalena Zych | Quantum interferometric visibility as a witness of general relativistic proper time
ABSTRACT: Current attempts to probe general relativistic effects in quantum mechanics focus on precision measurements of phase shifts in matter-wave interferometry. Yet, phase shifts can always be explained as arising from the Aharonov-Bohm effect, where a particle in a flat space-time is subject to an effective potential. Additionally, all current experiments with matter-waves probe only the Newtonian limit of gravity. Here we propose a quantum effect that cannot be explained without the general relativistic notion of proper time. We consider interference of a clock - a particle with evolving internal degrees of freedom - that will not only display a phase shift but also reduce the visibility of the interference pattern. According to general relativity, proper time flows at different rates in different regions of space-time. In quantum mechanics, there is a tradeoff between the visibility of interference pattern obtained with a single particle in a superposition and the amount of the information about the path taken by the particle. Such a tradeoff is an example of the quantum complementarity principle, first proposed by Niels Bohr. Therefore, the visibility of interference pattern will drop to the extent to which the path information becomes available in the clock. Experimental verification of this gravitationally induced decoherence would thus provide the first test of the genuine general relativistic notion of proper time in quantum mechanics. | |
| 17.02.2012 | Przemysław Majewski | O algebrach łącznych i nie, część pierwsza
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| 24.02.2012 | Przemysław Majewski | O algebrach łącznych i nie, część druga
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| 02.03.2012 | Bogusław Broda | The Ricci dark energy. A "microscopic" approach.
ABSTRACT: The Ricci dark energy is a brand of holographic dark energy which follows from black hole arguments ("phenomenological" approach). Instead we propose some arguments referring to quantum field theory, in the spirit of the traditional interpretation of dark energy as vacuum energy. In spite of the fact that our approach is not much more rigorous than the original one but it permits to estimate the free parameter of the Ricci dark energy which appears to be astonishingly close to observational expectations. | |
| 09.03.2012 | Norbert Bodendorfer | On higher dimensional generalisations of loop quantum
(super)gravity
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| 16.03.2012 | Jakub Mielczarek | Cosmological perturbations at the Planck epoch
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| 23.03.2012 | Emanuele Alesci | Linking canonical and covariant LQG:
New solutions to the Hamiltonian constraint
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| 30.03.2012 | Tomasz Pawłowski | How quantum geometry sees the singularity.
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| 13.04.2012 | Adam Latosiński | What is axion for?
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| 20.04.2012 | Adam Latosiński | Axion from B-L symmetry
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| 27.04.2012 | Michał Dziendzikowski | Diffeomorphism constraint in LQG
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| 11.05.2012 | Simone Speziale | Twistorial path integral for loop quantum gravity amplitudes
ABSTRACT: The dynamics of loop quantum gravity can be studied in a covariant way using the spin foam formalism, which provides a path integral for spin networks. The most successful spin foam model so far is the EPRL model, and its generalization studied in Warsaw. In my talk, I will discuss how these amplitudes represent histories of discrete geometries. In particular, I will present a new and elegant derivation of the amplitude in terms of twistors, and discuss some of its semiclassical properties. | |
| 18.05.2012 | Piotr Sułkowski | On knots, strings and quantum fields. Part 2: Volume conjecture and emergent geometry ABSTRACT: Volume conjecture relates knot invariants to hyperbolic geometry and the volume of knot complements. In this talk we will present physical formulation of the volume conjecture in terms of Chern-Simons theory, its relations to string theory, and phenomena such as emergent and noncommutative geometry arising in this context, which are currently actively studied. Note: This is the second (albeit self-contained) of the two talks devoted to knots, strings and quantum fields. The first talk will be presented as the "Gravity seminar", also on May 18th. See also: www.stringtheory.pl/seminaria/ | |
| 25.05.2012 | Michał Artymowski | Vector fields in cosmology and quantum cosmology
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| 01.06.2012 | Planck 2012 Conference
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| Date | Speaker | Title |
|---|---|---|
| 18.02.2011 | Michał Dziendzikowski | Geometric framework for constrained hamiltonian systems |
| 25.02.2011 | Marcin Napiórkowski | On the minimization of Hamiltonians over pure Gaussian states ABSTRACT: A Hamiltonian defined as a polynomial in creation and annihilation operators is considered. After a minimization of its expectation value over pure Gaussian states, the Hamiltonian is Wick-ordered in creation and annihillation operators adapted to the minimizing state. I will show that this procedure eliminates from the Hamiltonian terms of degree 1 and 2 that do not preserve the particle number, and leaves only the terms that can be interpreted as quasiparticles excitations. |
| 04.03.2011 | The Third Quantum Gravity and Quantum Geometry School in Zakopane | |
| 11.03.2011 | The Third Quantum Gravity and Quantum Geometry School in Zakopane | |
| 18.03.2011 | Wojciech Kamiński | Własności spektralne operatorów Jacobiego |
| 25.03.2011 | Jędrzej Świeżewski | Między ogólną teorią względności a elektrodynamiką - hamiltonowski
opis pewnej teorii pola ABSTRACT: Teleparallelizm (inaczej zwany TEGR - Teleparallel Equivalent of General Relativity) to sformułowanie teorii grawitacji, które koduje równania Einsteina nie w krzywiźnie koneksji, ale w jej torsji. Podczas mojego wystąpienia sformułuję teorię podobną do TEGR, a następnie przeprowadzę dla niej transformację Legendre'a. Na koniec przeanalizuję otrzymaną algebrę więzów. |
| 01.04.2011 | Adam Latosiński | Lagranżjan Heisenberga-Eulera w granicy silnego pola |
| 08.04.2011 | Katarzyna Rejzner | Local covariance principle and perspectives in quantum gravity
ABSTRACT: The principle of local covariance was originally proposed in the context of quantum field theory on generic spacetime. Later on it turned out that it can also be used to formulate the requirement of background independence in the perturbative approach to quantum gravity. The idea to formulate gravity in the framework of locally covariant field theory was already applied on the classical level and the perspectives for quantization are very promising. In this talk I will present the recent results in this research area and outline the program for future studies. |
| 11.04.2011 - 14.04.2011 | Constructions of Non-Equilibrium Statistical Mechanics Intensive course in the framework of the European Union project Studia Zamawiane Summary: The two-week course prepares for mathematical and theoretical research in current themes of non-equilibrium mesoscopic physics. The formalism uses standard Markov processes for interacting particles in contact with a thermodynamic environment. That environment consists of different macroscopic equilibrium reservoirs driving the system of interest in a non-equilibrium regime under the condition of local detailed balance. The notions of entropy production and of dynamical activity will be introduced as a function of the system's state trajectory, with special emphasis on their role in a fluctuation theory for steady states. In the same context new non-equilibrium variational principles and fluctuation-response relations will be explained. We concentrate on general results and on physical ideas that are described in a simple but precise mathematical language, and which can be inspiring for different scientific disciplines where fluctuations, dissipation and activity combine. General description: Non-equilibrium phenomena are ubiquitous and range from cosmological effects to life processes and small-scale transport phenomena. A unifying mathematical framework is still very much under construction, combining dynamical and statistical theories. Fluctuations are especially important for small systems and the tools of probability theory and of stochastic processes prove relevant for unraveling their structure. As it was and is the case for equilibrium statistical mechanics, also non-equilibrium physics positively stimulates new directions in probability theory and mathematical analysis, enabling for example more easy access to mathematical formulations of questions and answers in the life sciences. Course program: WEEK 1: March 7 - March 10, 2011 (16:15 - 18:15) Introduction to Markov jump and diffusion processes, Master/Fokker-Planck equation, detailed balance (reversibility), generator and semigroup, probabilistic ergodicity; path-integral formalism and stochastic calculus; Examples of non-equilibrium processes and interacting particle systems; Path-dependent analogues of energy, heat, work and entropy fluxes under local detailed balance; Fluctuation symmetries. WEEK 2: April 11 - April 14, 2011 (16:15 - 18:15) Definition and properties of the entropy production functional and of dynamical activity; Variational principles and dynamical fluctuation theory; Fluctuation-response relations and extensions of the (equilibrium) fluctuation-dissipation theorem; Review of open problems and outlook. Lecturer: Christian Maes, Instituut voor Theoretische Fysica, K.U.Leuven. http://itf.fys.kuleuven.be/~christ/pub/publications.html Practical Information: WEEK2 can be followed without attending WEEK1 by those already familiar with Markov processes. Those interested to follow one or both weeks of lectures should contact the organizer Jacek Miękisz [miekisz@mimuw.edu.pl] . There is no registration fee and some grants might be available for financial support of local expenses. All lectures take place at Banacha 2, room 5820 at the Institute of Applied Mathematics and Mechanics, University of Warsaw, Poland. | |
| 15.04.2011 | Romuald Janik | Całkowalność w korespondencji AdS/CFT - wprowadzenie |
| 29.04.2011 | Jakub Mielczarek | Anomaly-free perturbations in loop quantum cosmology |
| 13.05.2011 | Rafał Suszek | An introduction to Conformal Field Theory I ABSTRACT: Conformal field theories (CFT's), that is field theories with a non-anomalous conformal symmetry are ubiquitous in modern theoretical physics - suffice it to mention the minimal models that capture the dynamics of a large class of lattice theories at criticality, the gauged Wess-Zumino-Witten model that describes the continuum limit of a family of spin-chain models, the non-linear sigma model that defines a vacuum of the critical Polyakov string, or - in space-time dimensions higher than 2 - the supersymmetric gauge theories playing a central role in the AdS/CFT correspondence that provides us with precious insights into the physics of strongly-coupled condensed-matter systems. The above, in conjunction with the rich and much-explored structure, as well as a well-developed methodology of CFT, motivates taking a closer look at its generic features - a task to which the present lectures are devoted. In their course, I shall - introduce the conformal algebra and study its (quantum-)field-theoretic realisations; - indicate certain significant ramifications of conformal symmetry in the quantum theory, such as, e.g., the reconstruction of correlation functions; - briefly discuss the conformal (trace) anomaly. Once the general scheme has been laid out, I shall specialise to the particularly well-studied and important case - that of a CFT on a two-dimensional space-time. In this context, I shall - present the fundamental state-operator correspondence; - set up, using basic operator-algebraic techniques (such as, e.g., the OPE), a Hilbert-space description and embed it in the representation theory of the quantum symmetry algebra - the Virasoro algebra; - briefly discuss the concept of a current-algebra extension of the Virasoro algebra; - review chosen aspects of the conformal-bootstrap programme and address the issue of unitarity. I shall conclude the lectures by giving a long list of scandalous yet unavoidable omissions of topics from the forefront of the current research in the field. |
| 20.05.2011 | Rafał Suszek | An introduction to Conformal Field Theory II |
| 27.05.2011 | Przemysław Małkiewicz | The reduced phase space approach to the Kasner universe and the problem of time. |
| 03.06.2011 14:15 | Krzysztof Meissner | Entropia czarnych dziur ABSTRAKT: Przedstawię rozumowanie wskazujące na proporcjonalność entropii czarnych dziur do ich powierzchni i omówię wyprowadzenie współczynnika ich proporcjonalności |
| 03.06.2011 16:15 | Chun-Yen Lin | Gravity from Loop Quantum Gravity |
| 24.06.2011 | Marcin Kisielowski | Spin Foams encoded in Operator Spin Network Diagrams |
| Date | Speaker | Title |
|---|---|---|
| 08.10.2010 | Ryszard Kostecki | Riemannian geometry on the spaces of quantum states, I |
| 15.10.2010 | Przemysław Majewski | Exact solutions for Quantum Field Theory with certain quadratic Hamiltonian ABSTRACT: How to solve evolution equations analytically for a quadratic Hamiltonian with adiabatic factor and the benefits one has from it. |
| 22.10.2010 | Jacek Puchta | Vacuum Friedmann equation out of Spin Foams
ABSTRACT: Spin Foams is a covariant approach to Loop Quantisation of Gravity. So far it has had some physical predictions such as calculation of graviton propagator. A new model, Dipol Cosmology, is an application of Spin Foams' ideas to the cosmological case. The results are very optymistic, because in the classical limit the evolution of the model gives well known Friedmann equation. |
| 29.10.2010 | Wojciech Kamiński | All the 3-connected relativistic BC and EPRL spin-networks are integrable
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| 05.11.2010 | Marcin Kaźmierczak | Is it necessary to employ the Poincare invariance when quantizing
electrodynamics with fermionic matter? ABSTRACT: Standard QFT relies heavily on the Poincare symmetry. This is taken to the extreme in Wigner's definition of particles as unitary irreducible representations of the Poincare group, which is now adopted in many handbooks of QFT, such as the one by Weinberg. Also, more mathematically oriented approaches, e.g. based on Wightman axiomatics, usually use the Poincare symmetry. This state of affairs is unfortunate when one tries to include gravity, in the presence of which the space-time symmetry group may be different from the Poincare, or may not exist at all. Also, when gravity itself is to be quantized in a background independent way, the space-time symmetries cannot be used. It is natural to ask whether it is unavoidable or just convenient to use the Poincare symmetry in QFT. I will present the consequently canonical and Poincare-free quantization of spinor electrodynamics. Some difficulties will appear due to the presence of constraints and spinorial matter. The techniques that will be used to deal with these problems are certainly not a novelty, but they are presented surprisingly rarely in standard treatments of QFT. |
| 12.11.2010 | | |
| 19.11.2010 | Wojciech Kamiński | Young Tableaux and representations of the Sl(n,C) group |
| 26.11.2010 | Marcin Napiórkowski | A simplified proof of the stability of matter
ABSTRACT: I will present a simplified proof of the stability of matter. It differs from the original proof of Lieb and Thirring in that it does not refer to the Thomas-Fermi theory, but uses the so-called Baxter's electrostatic inequality. In part one of my speech I will prove the Lieb-Thirring inequality. In the second part I will show how this combined with Baxter's electrostatic inequality leads to stability of matter. |
| 03.12.2010 | Marcin Napiórkowski | A simplified proof of the stability of matter, part II |
| 10.12.2010 | Przemysław Majewski | Exactly solvable adiabatically perturbed quadratic Hamiltonian ABSTRACT: Some new facts but also some remarks to my last seminar about the exact expression for phase space evolution in this model and its usefulness. Moreover, operator issues connected with defining the formal Hamiltonian as a 'real' operator, direct integrals of Hilbert spaces. Ideas and scattering theory background as motivation for playing with this toy model. Representing phase space dynamics in the full Fock space. |
| 17.12.2010 | Wojciech Kamiński | Renormalization and microlocal analysis |
| 07.01.2011 | Andrzej Dragan | Quantum accelerometer ABSTRACT: Single quantum system, such as Unruh-DeWitt detector, can be used to determine absolute acceleration by local measurements on a quantum field. To show this, we consider two kinematically indistinguishable scenarios: an inertial observer, Bob, measuring the field of an uniformly accelerated cavity, and his non-inertial twin Rob accelerating and making measurements in a stationary cavity. We find that these scenarios can be distinguished in the non-relativistic regime only by measurements on highly excited massive fields, allowing one to detect non-inertialness of the reference frame. |
| 14.01.2011 | Jorma Louko | How often does an accelerated particle detector click? |
| 21.01.2011 | Krzysztof A. Meissner | Light on light scattering in QED ABSTRACT: I will discuss the Schwinger effective action for constant electric and magnetic fields in QED and its generalization to varying fields. |
| Date | Speaker | Title |
|---|---|---|
| 28.05.2010 | Adam Latosiński | Nonperturbative effects in gauge theories |
| 21.05.2010 | Krakowsko-Warszawskie Warsztaty LHC Program warsztatów: 11:30 Tea in the Conference Room of IFT (room 317) 12:00 - 12:55 A. M. Cooper-Sarkar (Oxford): PDF, alpha_s and low-x uncertainties at the LHC 13:05 - 14:00 A. Hoang (Munich): Jets, masses and unstable particles: toward precision measurements at the LHC Both lectures will be in Nowa Aula (room 425/426). 15:45 - 17:15 Shorter contributions and discussion in SDT (room 229/230) 15:45 - 16:15 F. Jegerlehner (DESY Zeuthen): g-2 and new physics 16:15 - 16:45 tba 16:45 - 17:15 tba | |
| 14.05.2010 | Michał Dziendzikowski | Background independent quantizations: point polymer quantization of real vector fields
ABSTRACT: Loop Quantum Gravity is one of the most prominent examples of a quantum theory where elementary variables are polymerlike, i.e. supported on submanifolds of lower dimension than the space manifold of a theory. Therefore similar background independent framework of quantization was needed to matter fields, e.g. scalar field. At first momentum space representation for scalar field was provided in which operators corresponding to momenta are diagonal and field operators exist only in the exponentiated form. Later the modification of this framework, i.e. position space representation was used to address the issue of quantum resolution of black hole singularities in the spherically symmetric part of gravitational phase space. In this talk the generalization of these frameworks to real vector fields will be presented. |
| 07.05.2010 | Antonio Vassallo | Spacetime Substantivalism and General Relativity. Why four dimensions are probably not enough.
ABSTRACT: In this talk I will argue that, within General Relativity, spacetime has an ambiguous ontological status due to a flawed or incomplete description. In the end, I will consider a generalization of the theory that seems to mitigate the problem. |
| 30.04.2010 | Frank Hellmann | TQFTs, State Sums and Geometry, part II (Some) geometry |
| 23.04.2010 | Frank Hellmann | TQFTs, State Sums and Geometry
ABSTRACT: I review the state sum definition of TQFTs and show in which contexts Geometry can arise in these. |
| 16.04.2010 | Marcin Kisielowski | The EPRL Spinfoam Model, part II |
| 09.04.2010 | Marcin Kisielowski | The EPRL Spinfoam Model |
| 26.03.2010 | Michał Wrochna | Holomorphic families of Shroedinger operators
ABSTRACT: The concept of analytic functions with values in unbounded operators was first motivated by pertubation theory in quantum mechanics. It has led to considerable results valuable in this particular context. Recent results show it plays an independant role in describing other properties of Schroedinger operators. This motivates the need for a more general mathematical theory, involving surprising features. |
| 19.03.2010 | Michał Wrochna | Decay rates in QED
ABSTRACT: In the literature, various methods are used to compute decay rates of excited states in QED. In the simpliest cases, lower-rank calculations motivate the belief that they lead to the same results. However, there is no such evidency in general and it is not even clear if the most common method is adequate from a conceptual point of view. We will discuss the problem on the example of two-photon decay processes in the excited hydrogen atom. In particular. we will make use of the Gell-Mann, Low and Sucher formula and compare it with alternative approaches. |
| 12.03.2010 | Przemysław Malkiewicz | Reduced phase space quantization applied to cosmology
ABSTRACT: I will use an alternative method, so called reduced phase space quantization, to construct a quantum theory of flat FRW universe with massless scalar field. The spectra of volume and energy density operators will be presented. Then, I will show how to apply these results to Bianchi I universe. |
| 05.03.2010 | ||
| 26.02.2010 | Konwersatorium Matematyczne pt. Spinory i twistory Wykłady rozpoczną się o godzinie 14:15 na wydziale MIM UW (ul. Banacha 2) w sali 5440 (IV piętro). Program sesji: 14:15 - 15:15 Andrzej Trautman: Algebry Clifforda i spinory. Troche historii, fizyki i geometrii 15:15-15:45 (przerwa na kawę) 15:45 - 16:45 Maciej Dunajski: Teoria twistorów i równania różniczkowe | |
| 19.02.2010 | Marcin Kaźmierczak | Quantum fields corresponding to faithful representations of the Poincare group and Poincare gauge theory of gravity II |
| 22.01.2010 | Catherine Meusburger | Quantum group and Hopf algebra symmetries in (2+1)-gravity
ABSTRACT: We discuss the role of quantum group and Hopf algebra symmetries in (2+1)-gravity. In particular, we comment on the question which quantum groups are relevant for (2+1)-gravity and show that quantum group symmetries are also present in (2+1)-dimensional loop quantum gravity. Part of thhe talk is based on joint work with K. Noui and B. J. Schroers. |
| 15.01.2010 | Krakowsko-Warszawskie Warsztaty LHC Program warsztatów: 11:30 Tea in the Conference Room of IFT (room 317) 12:00 A. de Roeck (CERN - CMS): Exotica with 200 pb-1 13:00 O. Buchmueller (Imperial College - CMS): Supersymmetry with 200 pb-1 Both lectures will be in Nowa Aula (room 425/426). 14:00 - 15:30 Joint lunch 15:30 - 18:00 Shorter contributions and discussion in SDT (room 229/230) 15:30 M. Olechowski (Warsaw) (40'): Light gluinos? 16:10 M. Steinhauser (Karlsruhe) (20'): Finite top quark mass effects in NNLO Higgs boson production 16:30 Tea break (15') 16:45 M. Szleper (Warsaw) (40'): First physics from CMS 17:25 End | |
| 08.01.2010 | Bianca Dittrich | Canonical kinematics and dynamics for simplicial geometries |
| 18.12.2009 | Piotr Sulkowski | New connections between two- and four-dimensional quantum field theories
ABSTRACT: This year remarkable relations have been discovered between four-dimensional, supersymmetric quantum gauge theories, and two-dimensional conformal field theories. As it turns out, various exact quantities computed for certain theories in both these classes are equal to each other. These quantities include four-dimensional partition functions on one hand, and two-dimensional correlators (three-point functions, conformal blocks) on the other hand. There is a growing computational and conceptual evidence that these relations are true in a very general context. I will discuss how this conjecture could be proved by relating both classes of theories in question to matrix models and non-commutative Riemann surfaces, and sketch the associated string theory interpretation. |
| 11.12.2009 | VIII Sympozjum
Istytutu Fizyki Teoretycznej
Wykłady rozpoczną się o godzinie 15:00 w Auli IFT(425),ul. Hoża 69 Program sympozjum: Piątek, 11 XII 2009 15.00 - 15.05 Otwarcie Sympozjum - Prof. Marek Napiórkowski 15.05 - 15.40 Wręczenie Nagrody im. Prof. S. Pieńkowskiego i Nagród Wydziału Fizyki 15.40 - 16.25 Prof. Ewa Sikora (Instytut Biologii Doświadczalnej im. M. Nenckiego PAN): Telomeraza - eliksir nieśmiertelności? 16.25 - 17.00 Dr Andrzej Dragan: Drugie życie komputera kwantowego 17.30 - 18.05 Prof. Wojciech Satuła : Symetria izobaryczna w jądrach atomowych 18.05 - 18.40 Dr Paweł Jakubczyk : Funkcjonalna grupa renormalizacji dla kwantowych zjawisk krytycznych 18.50 - 19.05 mgr Agata Chęcińska : Zaszumione kanały kwantowe i łamanie splątania 19.05 - 19.20 mgr Maciej Zalewski : Efekty oddziaływania tensorowego w jądrowej strukturze jednocząstkowej 19.20 - 19.35 mgr Piotr Nowakowski : Siły Casimira w dwuwymiarowym pasku Isinga Sobota, 12 XII 2009 9.30 - 10.05 Prof. Mikołaj Misiak: Współczynnik Wilsona dla procesów zmieniających zapach 10.05 - 10.40 Prof. Marek Olechowski: Ciemna materia 10.50 - 11.25 Prof. Paweł Nurowski : Wyjątkowa grupa Liego G2 11.25 - 12.00 Dr Andriy Panasyuk (KMMF) : O geometrii struktur bihamiltonowskich i ich zastosowaniu w teorii układów calkowalnych 12.30 - 12.45 mgr Anna Kamińska : Supersymetryczne modele naruszenia symetrii elektrosłabej 12.45 - 13.00 mgr Dorota Sokołowska: Ewolucja Wszechświata po złamaniu symetrii elektrosłabej 13.00 - 13.15 mgr Wojciech Kamiński: Piany spinowe jako model czasoprzestrzeni 13.20 Spotkanie przy kawie uczestników sympozjum | |
| 04.12.2009 | Ewa Infeld | Introduction to Group Field Theories
ABSTRACT: I will give a light-hearted introduction to Group Field Theories: what the idea is, how they work and what they are good for. |
| 27.11.2009 | Michele Arzano | Fun from none: deformed Fock space and hidden entanglement
ABSTRACT: Attempts to go beyond the framework of local quantum field theory include scenarios in which the action of external symmetries on the quantum fields Hilbert space is deformed. A common feature of these models is that the quantum group symmetry of their Hilbert spaces induces additional structure in the multiparticle states which in turns reflects a non-trivial momentum-dependent statistics. In certain particular models which might be relevant for quantum gravity the richer structure of the deformed Fock space allows for the possibility of entanglement between the field modes and certain ''planckian'' degrees of freedom invisible to an observer that cannot probe the Planck scale. |
| 20.11.2009 | Andrzej Herdegen | Electrically charged quantum particles: a C*-algebraic model
ABSTRACT: Charged particles cannot be separated from the electromagnetic field surrounding them and, when scattered, they produce long-range radiation. Related to these experimental facts are difficulties in the mathematical modelling of elementary particles like electrons. A C*-algebraic model of electrons and radiation will be discussed. It avoids the complexity of the full theory, but allows the study of the ``dressing'' of electrons with the electromagnetic field by an analysis of its representations. |
| 13.11.2009 | Marcin Kaźmierczak |
Quantum fields corresponding to faithful representations of the Poincare
group and Poincare gauge theory of gravity
ABSTRACT: In standard quantum field theory, the Hilbert spaces of one-particle states correspond to irreducible unitary representations of the universal covering of the Poincare group, whereas quantum fields are classified by finite-dimensional representations of the universal covering of the Lorentz group. For a given field, these representations need to be connected vie Weinberg consistency conditions. I will investigate the possibility of using finite-dimensional faithful representations of the Poincare group to classify quantum fields. Is it possible to develop a consistent theory of the associated particles? If yes, will they differ from standard ones? This questions will be addressed. I will also consider the inclusion of gravity, interpreted as a gauge theory of the Poincare group, to the field theories constructed in this way. The new feature is that the translational gauge fields enter the covariant derivative of matter fields. Also, the so called Poincare coordinates, that are normally hidden within the cotetrad (together with translational gauge fields) will now manifest themselves explicitly. |
| 6.11.2009 | Krakowsko-Warszawskie Warsztaty LHC Wykłady odbędą się w Auli IFT(425),ul. Hoża 69 Program warsztatów: 11:30 herbata w Sali Konferencyjnej IFT (p.317) 12:00 T. Nakada (CERN): Experimental programme at the LHCb (przerwa 10') 13:00 A. Buras (TU w Monachium): FCNC processes waiting for the next decade Oba wykłady będą w Nowej Auli (p.425/426). 14:00 - 15:30 Wspólny obiad 15:30 - 18:00 Short contributions: M. Szczekowski (20'): Warsaw participation in LHCb A. Ukleja (20'): High level trigger Z. Guzik (15'): Time and fast control system for LHCb (przerwa 5') M. Różańska (30'): Comparison of the discovery potential at Belle and at the LHCb G. Polok (20'): Cracow participation in LHCb (1) M. Witek (20'): Cracow participation in LHCb (2) M. Misiak (20'): Wilson coefficients for flavour changing processes | |
| 30.10.2009 | Jacek Puchta | Rachunek zaburzeń na dynamicznej czasoprzestrzeni |
| 23.10.2009 | Sympozjum Marek-fest dedykowane profesorowi Markowi Demiańskiemu Wykłady rozpoczną się o godzinie 16:00 w Auli IFT(425),ul. Hoża 69 Program sympozjum: Piątek, 23 października 16:00 - 16:30 Andrzej Staruszkiewicz: Termodynamika i Teoria Względności - reminiscencje z okazji pracy A.Curir and M. Demiański, "Note on Thermodynamics of Event Horizons", Acta Physica Polonica B10(1979)763-765 16:30 - 17:00 Maciej Przanowski: Od zespolonej grawitacji do hipotezy Ossermana 17:00 - 17:30 Przerwa 17:30 - 18:00 Andrzej Woszczyna: Teoria Lifszyca-Chałatnikowa jako opis zaburzeń niezależnych od cechowania 18:00 - 18:30 Michał Heller: Kosmologia wczoraj i dziś - Przeżywanie kawałka historii Sobota, 24 października 10:00 - 10:30 Andrzej Królak: Czarne dziury i kosmiczna cenzura 10:30 - 11:00 Stanisław Bajtlik: Topologia Wszechświata 11:00 - 11:30 Przerwa 11:30 - 12:00 Jerzy Kowalski-Glikman: Kwantowa grawitacja? Czemu nie? 12:00 - 12:30 Janusz Gil: Czego nie wiemy o pulsarach 12:30 - 13:00 Przerwa 13:00 - 13:30 Roman Juszkiewicz: Nieliniowy rachunek zaburzeń w kosmologii 13:30 - 14:00 Zakończenie | |
| 16.10.2009 | Konwersatorium Matematyczne pt. Całki Feynmana Wykłady rozpoczną się o godzinie 14:15 na wydziale MIM UW (ul. Banacha 2) w sali 5440 (IV piętro). Program sesji: 14:15 - 15:15 Iwo Białynicki-Birula: Od Huygensa do Feynmana 15:15-15:45 (przerwa na kawę) 15:45 - 16:45 Krzysztof Gawędzki: Rachunek całek po drogach 16:45 - 17:00 (przerwa) 17:00 - 18:00 Rafal Latała: Calka Feynmana i miara Wienera | |
| 9.10.2009 | Jan Dereziński | Sekrety elektrodynamiki kwantowej II |
| 2.10.2009 | Jan Dereziński | Sekrety elektrodynamiki kwantowej I
ABSTRACT: During the last decades there has been a significant progress in our understanding of mathematical structure of various physical problems, especially in quantum theory and quantization of space-time geometry. Physics has inspired some of the most interesting and profound results in modern mathematics. Yet many of these results remain unknown in our community. They often concern the most fundamental problems many of us came across while studying and often felt they were not properly explained. We dedicate our seminar to these results. We hope it will attract specialists in the field as well as those of students who would like to broaden their understanding of quantum theory, field theory and statistical physics or are merely fascinated by the elegance and efficiency of modern mathematical apparatus when applied to physics. |
| Date | Speaker | Title |
|---|---|---|
| 29.05.2009 | Adam Latosiński | TBA |
| 22.05.2009 | Wojciech Kamiński | Kwantowe więzy |
| 15.05.2009 | Michał Dziendzikowski | Techniki uśredniania po grupie w rozwiązywaniu kwantowych więzów II |
| 24.04.2009 | Michał Dziendzikowski | Techniki uśredniania po grupie w rozwiązywaniu kwantowych więzów |
| 17.04.2009 | Adam Sawicki | Opis separowalności (splątania) stanów kwantowych przy użyciu odwzorowań dodatnich |
| 3.04.2009 | Ryszard Kostecki | Geometria Riemannowska i dualna na przestrzeniach miar probabilistycznych |
| 27.03.2009 | Michał Dziendzikowski | Struktury semianalityczne w wybranych zagadnieniach LQG |
| 20.03.2009 | Jacek Puchta | Aksjomaty Wightmana, spin i statystyka II |
| 13.03.2009 | Jacek Kopeć | Stany KMS. Nierówności autokorelacyjne i twierdzenie Pusza-Woronowicza II |
| 6.03.2009 | Jacek Kopeć | Stany KMS. Nierówności autokorelacyjne i twierdzenie Pusza-Woronowicza |
| 27.02.2009 | Konwersatorium Matematyczne pt. Symetrie w matematyce i fizyce. Grupy kwantowe Wykłady rozpoczną się o godzinie 14:15 na wydziale MIM UW (ul. Banacha 2) w sali 5440 (IV piętro). Program sesji: 14:15 - 15:15 Stanislaw Lech Woronowicz: Symetrie w matematyce i fizyce 15:15-15:45 (przerwa na kawę) 15:45 - 16:45 Tomasz Maszczyk: Grupy kwantowe wedlug Drinfelda-Jimbo 16:45 - 17:00 (przerwa) 17:00 - 18:00 Piotr Mikołaj Sołtan: Zwarte grupy kwantowe | |
| 20.02.2009 | Jacek Puchta | Aksjomaty Wightmana, spin i statystyka I STRESZCZENIE: Celem moich wystąpień jest udowodnienie dwóch twierdzeń o kwantowych teoriach pola spełniających aksjomaty Wightmana. Na pierwszym seminarium przedstawię te aksjomaty oraz udowodnię kilka faktów z teorii dystrybucji na wielowymiarowych przestrzeniach zespolonych. Na drugim seminarium korzystając z tych lematów udowodnię, że każda kwantowa teoria pola posiada operator CPT oraz pokażę związek spinu cząstek ze statystyką, jakiej podlegają. |
| 23.01.2009 | Marcin Kisielowski | Równanie falowe na rozmaitościach lorentzowskich STRESZCZENIE: W swoim wystąpieniu zaprezentuję zastosowanie teorii dystrybucji Riesza do znajdowania lokalnego rozwiązania równania falowego na globalnie hiperbolicznych rozmaitościach lorentzowskich. Przedstawię rozwiązanie fundamentalne dla ogólnego przypadku operatorów normalnie hiperbolicznych wyrażone przy pomocy wyżej wspomnianych dytrybucji oraz współczynników Hadamarda. |
| 16.01.2009 | Adam Balcerzak | Warunki zszycia Israela w teorii grawitacji czwartego rzędu dla Wszechświatów membranowych |
| 9.01.2009 | Michał Dziendzikowski | Dyfeomorficznie współzmiennicze reprezentacje algebry holonomii-strumieni STRESZCZENIE: Procedura kwantyzacji kanonicznej opiera się na wyborze dwóch podstawowych elementów, jakimi są: tzw. kwantowa *-algebra elementarnych obserwabli i jej *-reprezentacja. Wybór ten definiuje kinematykę danej teorii. W przypadku niezależnej od struktury tła kwantyzacji kanonicznej pól cechowania, w szczególności teorii grawitacji, algebra elementarnych obserwabli nosi również nazwę algebry holonomii-strumieni. Kinematyka w tym przypadku opiera się na klasycznej już konstrukcji *-reprezentacji wspomnianej algebry, dokonanej przez Ashtekara i Lewandowskiego. Konstrukcja ta dzięki swej naturalności i matematycznej urodzie szybko zdobyła uznanie i pozwoliła uzyskać nowe fizycznie interesujące rezultaty. Niezależność od struktury tła przejawia się tutaj w odpowiednio zdefiniowanej dyfeomorficznej współzmienniczości tej reprezentacji. Znacznym osiągnięciem ostatnich lat było sformułowanie i udowodnienie tzw. twierdzenia LOST o jednoznaczności reprezentacji Ashtekara-Lewandowskiego. W trakcie tego seminarium zamierzam przybliżyć zagadnienia związane z konstrukcją *-reprezentacji algebry holonomii-strumieni, w szczególności przedyskutować pokrótce twierdzenie LOST oraz przedstawić dwa krótkie przykłady reprezentacji nierównoważnych ze standardową. |
| 19.12.2008 | --- | Zapraszamy na szóstą sesję Konwersatorium Matematycznego pt.
Model standardowy teorii cząstek: historia ,fizyka, matematyka. Wykłady rozpoczną się o godzinie 14:15 na wydziale MIM UW (ul. Banacha 2) w sali 5440 (IV piętro). Program sesji: 14:15-15:15 Andrzej Kajetan Wroblewski: Od mezonów do kwarków. 15:15-15:45 (przerwa na kawę) 15:45-16:45 Piotr Chankowski: Kwantowa teoria pola: od teorii Fermiego i elektrodynamiki do teorii standardowej i dalej. 16:45-17:00 (przerwa) 17:00 - 18:00 Krzysztof Meissner: Symetrie w fizyce cząstek elementarnych. |
| 12.12.2008 | Marcin Kazmierczak | Problem mierzalności parametru Immirziego STRESZCZENIE: Pętlowa grawitacja kwantowa powstała w konsekwencji próby kanonicznego skwantowania pola grawitacyjnego. Wyjściową, klasyczną teorią jest w tym podejściu teoria Einsteina-Cartana, zmodyfikowana poprzez dodanie tak zwanego członu Holsta do grawitacyjnego lagrangianu, dzięki któremu upraszcza się struktura więzów. Człon ten nie zmienia próżniowych równań pola, co usprawiedliwia jego dodanie. Jeśli jednak w czasoprzestrzeni obecna jest materia ze spinem, dodatek zaczyna mieć znaczenie. W swoim wystąpieniu rozważę włączenie fermionów do teorii Einsteina-Cartana z członem Holsta. W teorii tej, w odróżnieniu od standardowej ogólnej teorii względności, obecne są punktowe oddziaływania między fermionami o grawitacyjnym (geometrycznym) pochodzeniu. Stałe sprzężenia tych oddziaływań zależą od parametru Immirziego, będącego odwrotnością stałej multiplikatywnej poprzedzającej człon Holsta. Także związki między materią fermionową i torsją czasoprzestrzeni zależą od parametru Immirziego. Podczas seminarium postaram się odpowiedzieć na pytanie, czy wspomniane wyżej fakty mogą umożliwić zaprojektowanie eksperymentów, nie odwołujących się do pełnej kwantowej teorii pola grawitacyjnego, mających na celu ustalenie ograniczeń na wartość parametru Immirziego. Możliwość taka byłaby niezwykle interesująca, ponieważ wartość parametru daje się określić na gruncie teoretycznym, dzięki porównaniu wzoru na entropię czarnej dziury otrzymanego w ramach pętlowej grawitacji ze wzorem Bekensteina-Hawkinga. |
| 5.12.2008 | --- | --- |
| 28.11.2008 | Jerzy Lewandowski | Rozwiązania kwantowych więzów: przykłady kosmologiczne |
| 21.11.2008 | Mariusz P. Dabrowski | Egzotyczne osobliwosci kosmologiczne w kontekście teorii fundamentalnych. |
| 14.11.2008 | Wojciech Kamiński | Mikrolokalna analiza i pewne jej zastosowania - cz.II |
| 7.11.2008 | Wojciech Kamiński | Mikrolokalna analiza i pewne jej zastosowania |
| 31.10.2008 | --- | --- |
| 24.10.2008 | Krzysztof Pachucki | Perturbacyjna teoria efektów nieadiabatycznych w molekułach |
| 17.10.2008 | Adam Latosiński | Regularyzacja przez rozmycie pól |
| 10.10.2008 | Krzysztof Pachucki | Oddziaływanie van der Waalsa i Casimira-Poldera |
| 3.10.2008 | Michał Jówikowski | Stała regularyzacyjna operatora objętości |
| Date | Speaker | Title |
|---|---|---|
| 6.06.2008 | Diana Kaminski (University of Hamburg) | The theory of self-adjoint extensions and forms |
| 31.05.2008 | Krzysztof Meissner | Neutrinos, axions and conformal symmetry |
| 30.05.2008 | Thomas Flacke (University of Michigan) | Non-minimal universal extra dimensions and new dark matter candidates ABSTRACT: Models with universal extra dimensions, in which all standard model fields are propagating in the extra dimensions, have a rich and well-studied phenomenology. It is known, that UED models allow for an extensive set of operators beyond the Minimal UED model. However, those operators have not been taken into account in most phenomenological studies. I will provide a review of the UED setup and its phenomenology. In order to indicate the importance to study effects of non-minimal UED operators, I will show how their inclusion can change the UED dark matter candidate from a Kaluza-Klein photon to a Kaluza-Klein Z boson, providing a new WIMP dark matter candidate. |
| 16.05.2008 | Wojciech Kamiński | Analytical aspects of Loop Quantum Cosmology |
| 9.05.2008 | Andrzej Hryczuk | Effective Schwinger action |
| 25.04.2008 | Łukasz Szulc | Simplified Loop Quantum Cosmology |
| 18.04.2008 | Jan Dereziński | Scattering theory in nonrelativistic quantum theory III |
| 11.04.2008 | Jan Dereziński | Scattering theory in nonrelativistic quantum theory II |
| 4.04.2008 | Jan Dereziński | Scattering theory in nonrelativistic quantum theory I ABSTRACT: My minicourse is devoted to scattering theory for a certain class of Hamiltonians motivated by nonrelativistic quantum field theory. The plan of my minicourse is as follows: - Basic abstract scattering theory. - Scattering of 2-body Schr\"odinger operators. - Second quantization. - Nonrelativistic QED. - Scattering of Hamiltonians of QFT. - Scattering of van Hove Hamiltonians. - Spectrum of Pauli-Fierz Hamiltonians. - Scattering of Pauli-Fierz Hamiltonians I. - Representations of the CCR. - Scattering of Pauli-Fierz Hamiltonians II. |
| 28.03.2008 | Marcin Kisielowski | Wave equation and quantum fields on curved space-time ABSTRACT: In my talk I will present the construction of algebra of local observables for Klein-Gordon field on globally hyperbolic manifolds. It will be an exmaple of implementation of Haag-Kastler axioms generalised to Lorentzian manifolds. ABSTRAKT: W swoim wystąpieniu przedstawię konstrukcję algebry lokalnych obserwabli dla pola Kleina-Gordona na globalnie hiperbolicznych rozmaitościach. Będzie to przykład realizacji aksjomatów Haaga-Kastlera uogólnionych do lorentzowskich rozmaitości. |
| 14.03.2008 | ||
| 7.03.2008 | Jacek Wojtkiewicz | Czterysta dwunaste rozwiązanie dwuwymiarowego modelu Isinga: całki
grassmanowskie. ABSTRAKT: Będzie o tym, że gdy jeden obiekt z drugim antykomutuje i po takich obiektach się całkuje, to sumę statystyczną modelu Isinga tak się formułuje i tą metodą ścisłe rozwiązanie tegoż się uzyskuje. Metodę tę za krótką i zgrabną uznaję. Przekonaj się słuchaczu, mówię prawdę, czy baję. |
| 29.02.2008 | Adam Latosiński | Znaczenie lokalności w rachunku zaburzeń kwantowej teorii pola ABSTRACT: Wychodząc od warunków na lokalność, zamierzam pokazać możliwość sukcesywnej konstrukcji macierzy S w postaci formalnego szeregu przy zmiennej mocy oddziaływania, oraz przejście do granicy adiabatycznej stałej na czasoprzestrzeni mocy oddziaływania. |
| 22.02.2008 | Wojciech De Roeck | Proof of diffusion in a quantum model with Hamiltonian dynamics ABSTRACT: We consider a quantum particle on a lattice coupled to a large reservoir. We show that for sufficiently small coupling, the motion of the particle satisfies a central limit theorem, implying diffusive behaviour. Our technique is an expansion around a scaling limit, in which the particle satisfies a Boltzmann-like equation. |
| Date | Speaker | Title |
|---|---|---|
| 25.01.2008 | Jacek Puchta | States of low energy on RW space-time - part 2 ABSTRACT: Na pierwszej części wystąpienia zaprezentowane zostały tzw. stany niskoenergetyczne na przestrzeni FRW. Na drugiej części pokazane będzie fizyczne uzasadnienie takiej konstrukcji. Stany niskoenergetyczne posiadają własność Hadamarda. Przedstawię definicję stanów Hadamarda oraz omówię szkic dowodu, że stany niskoenergetyczne leżą w tej klasie. |
| 18.01.2008 | Jacek Kopeć | States of low energy in Robertson-Walker spacetime - part 1 ABSTRACT: In my talk I will present H.Olbermann's approach to constructing class of physical states of Klein-Gordon field on Robertson-Walker spacetimes. This is done by minimizing the energy measured by an isotropic observer moving along a timelike curve which gives this construction quite clear physical motivation. It occures that explicit expresion depending on smearing function can be given. |
| 11.01.2008 | Jan Gutt | Birdtracks: Group Theory according to P. Cvitanovi\'c ABSTRACT: Physics provides a number of graphical calculi, where mathematical expressions are represented by graphs undergoing a set of transformation rules. Prominent examples are Feynman diagrams and Penrose's binors, whose representation-theoretic flavour suggests using similar methods for general calculations in group theory. A collection of such techniques and related constructions has been developed by P. Cvitanovi\'c under the name of "birdtracks". I will present some of their applications. |
| 21.12.2007 | Jan Dereziński | Excitation spectrum of the Bose gas and supefluidity - part 3 |
| 21.12.2007 | Jan Dereziński | Excitation spectrum of the Bose gas and supefluidity - part 2 |
| 14.12.2007 | Jan Dereziński | Excitation spectrum of the Bose gas and supefluidity ABSTRACT: Superfluidity of the Bose gas at low temperatures is one of the most amazing phenomena in physics. I will try to convince the audience that it suggests a number of intriguing questions in mathematical physics. We know few rigorous results on this subject. Our understanding of this phenomenon is based mainly on beautiful but merely heuristic arguments due to Bogoliubov, as well as to Bijls and Feynman. These arguments will be the main topic of my talks. STRESZCZENIE: Nadciekłość gazu bozonów w niskich temperaturach to jedno z najbardziej zdumiewających zjawisk w fizyce. Sprobuję przekonać słuchaczy, że zjawisko to prowadzi do niezwykle intrygujących pytań w fizyce matematycznej. Niewiele ścisłych rezultatów znamy na ten temat, nasz jego obraz jest głównie oparty na pięknych ale jedynie heurystycznych argumentach pochodzących od Bogoliubowa oraz od Bijlsa i Feynmana, o których zamierzam opowiedzieć. |
| 7.12.2007 | --- | --- |
| 30.11.2007 | Ryszard Kostecki | General relativity histories ABSTRACT: I will present the histories approach to General Relativity, developed by Savvidou. |
| 23.11.2007 | Ryszard Kostecki | Quantum histories ABSTRACT: Quantum histories programme, proposed and developed by Griffiths, Omnes, Gell-Mann and Hartle, aims at space-time description of quantum theory, which includes the subsequent nonunitary measurements on the equal footing with unitary evolution. I will discuss the histories projection operator approach to quantum histories, developed by Isham, Linden and Savvidou. My final aim is to present the discovery of Savvidou that quantum histories enable to define well-defined self-adjoint quantum action operator, which encodes two types of time evolution, and leads to two different notions of time in quantum theory. |
| 16.11.2007 | Przemysław Majewski |
C*-algebra of the canonical commutation relations and its place in QFT
ABSTRACT: During my talk I will define and describe the C*-algebra of CCR, sometimes also called the Weyl algebra. I will show its properties as well as its applications to Lorentz-covariant quantization of simple QFT theories - scalar field and vector field. |
| 9.11.2007 | Jacek Wojtkiewicz | On the universality classes of 2d metal-insulator transition ABSTRACT: In 2005, the metal-insulator transition in BEDT-TTF salts [complicated organic compound] have been discovered. It turned out that critical exponents characteristic for this transition [delta = 2, gamma = 1, beta = 1] didn't fit to any known universality class. In other words, new universality class have been discovered. Shortly after, M. Imada has given a convincing explanation of observed values of critical exponents. In my talk, I would like to give a simplified version of Imada reasoning. |
| 2.11.2007 | --- | --- |
| 26.10.2007 | Krzysztof Meissner | Conformal anomaly in quantum field theory STRZESZCZENIE: Omowiona zostanie anomalia w bezmasowej teorii \phi^4 w czterech wymiarach, ktora klasycznie jest niezmiennicza ze wzgledu na skalowanie Weyla i jej zwiazek z nieznikajacym sladem tensora energii-pedu. |
| 19.10.2007 | --- | --- |
| 12.10.2007 | Jonathan Engle (CPT Marseille) | Spin-foam models with weakened simplicity constraints |
| 5.10.2007 | Benjamin Bahr (AEI Potsdam) | Gauge-invariant coherent states for Loop Quantum Gravity ABSTRACT: The usual complexifier coherent states provide a tool for investigating the semiclassical limit of LQG. However, these states are purely kinematical, i.e. do not satisfy any of the constraints. But if one wants to work on the gauge- or Diff-invariant level, coherent states that satisfy the Gauss- and/or the Diff-constraint are desirable. In this talk I will, as a first step into this direction, describe the projection of the complexifier coherent states on the gauge-invariant Hilbert space and demonstrate their semiclassical properties. This will show that these gauge-invariant coherent states are the appropriate tool for adressing semiclassical issues in the gauge-invariant sector. |
| Date | Speaker | Title |
|---|---|---|
| 8.06.2007 | Chris Fewster | Energy Inequalities in Quantum Field Theory |
| 1.06.2007 | Krzysztof Meissner | Effective action in QFT 2 |
| 25.05.2007 | Krzysztof Meissner | Effective action in QFT |
| 18.05.2007 | Marcin Domagała | Spin foams 2 |
| 27.04.2007 | Rafał R. Suszek | Landscape with a background gerbe / Pejzaż z wiechciem w tle ABSTRACT: Propagation of the string in a compact simple Lie group G, as captured by the relevant nonlinear two-dimensional sigma-model - the Wess-Zumino-Witten (WZW) model, is highly constrained by the requirement of a non-anomalous conformal symmetry. The latter necessitates - in addition to the standard Killing-form metric - the presence of a specific torsion field in the WZW target group manifold, coupled geometrically to the world-sheet swept by the string. Rendering this coupling well defined in the topologically non-trivial geometry of G calls for the introduction of a differential geometric structure termed a (bundle) gerbe, with the torsion field as the fundamental object - the curvature of the gerbe. In my talk, I shall present those elements of the general construction which are indispensable for understanding the ongoing project of classification of consistent WZW models based on the notion of the associated torsion gerbe. Time permitting, I shall also discuss the intricate role that the gerbe plays in determining the strictly non-classical geometry of the group - as probed by the open string - encoded in the spectral data of the supersymmetric extension of the WZW model for world-sheets with boundaries. The talk is based on the results of a collaboration with K. Gawędzki, A. Recknagel, and K.Waldorf. An outline of the talk: I Nonlinear sigma-models and conformal symmetry in the Lagrangean description of the string. II Strings on Lie groups - the WZW torsion gerbe and twisted gluon fields. III A sketch of the reconstruction of the dynamics of twisted gluon fields, based on the WZW spectral triple. STRESZCZENIE: Propagacja struny w zwartej prostej grupie Liego G, opisywana przez odpowiedni nieliniowy dwuwymiarowy model sigma Wessa-Zumino-Wittena, jest poddana więzom nieanomalnej symetrii konforemnej. Symetria ta wymaga - obok standardowej metryki Killinga - obecności szczególnego pola torsji w rozmaitości grupowej, w której zanurzony jest model WZW, sprzęgającego się geometrycznie do powierzchni świata zakreślanej przez strunę. Próba ścisłego zdefiniowania tego sprzę żenia w topologicznie nietrywialnej geometrii G czyni koniecznym wprowadzenie struktury różniczkowej, zwanej wiechciem (na wiązce), dla której obiektem fundamentalnym jest pole torsji - krzywizna wiechcia. W swoim wykładzie przedstawię te elementy konstrukcji ogólnej, które są nieodzowne dla zrozumienia bieżącego projektu klasyfikacji konsystentnych modeli WZW opartego na pojęciu stowarzyszonego wiechcia torsyjnego. Jeśli czas mi na to pozwoli, przedyskutuję także intrygującą rolę, jaką wiecheć odgrywa w rekonstrukcji ściśle nieklasycznej geometrii grupy G - w jej obrazie otwartostrunowym - zapisanej w danych widmowych supersymetrycznego rozszerzenia modelu WZW dla powierzchni świata z brzegiem. Treść wykładu jest oparta na wynikach uzyskanych we współpracy z K. Gawędzkim, A. Recknagelem i K. Waldorfem. Plan wykładu: I Nieliniowe modele sigma i symetria konforemna w opisie lagranżowskim struny. II Struny na grupach Liego - wiecheć torsyjny WZW i zwichrowane pola gluonowe. III Szkic rekonstrukcji dynamiki zwichrowanych pól gluonowych z trójki widmowej WZW. |
| 20.04.2007 | Marcin Domagała | Spin foams |
| 30.03.2007 | Karol Kozłowski | Correlation functions of the boundary XXZ model ABSTRACT: The algebraic Bethe ansatz (ABA) is a very powerful tool to derive the spectrum of many one dimensional lattice integrable models. Maillet et al. showed that it is also fitted for the computation of correlation functions of periodic spin chains, such as the XXZ spin-1/2 periodic chain. Yet, most of the physically relevant spin chains have other types of boundary conditions. Sklyanin developed an ABA suited for the diagonalization of boundary hamiltonians. In this talk, after a short introduction to the ABA, I will present the general method we developed to obtain exact expressions for the correlations functions of the boundary XXZ spin-1/2 chain subject to longitudinal magnetic fields at the boundaries. We were able to recast, in the thermodynamic limit, the so-called elementary blocks of m adjacent operators as m-fold integrals. These results are similar to the ones obtained in the bulk model. In the end of the this talk, I will present some cases where the integrals can be separated thus leading to results in a closed form. This is a joint work with N. Kitanine, J-M. Maillet, G. Niccoli, N. Slavnov and V. Terras. STRESZCZENIE: Algebraiczny Ansatz Bethego (AAB) stanowi bardzo skuteczną metodę otrzymywania spektrum wielu jednowymiarowych dyskretnych modeli całkowalnych. Maillet et al. znaleli metodę opartą na AAB która pozwala obliczyć funkcje korelacji periodycznych sieci spinowych typu XXZ, lecz większość sieci spinowych występujących w fizyce ciała stałego posiada warunki brzegowe łamiące symetrię translacji. Sklyanin zbudował wersję AAB umożliwiającą diagonalizację tzw. hamiltonianów brzegowych. W moim seminarium chciałbym przedstawić jak, w ramach konstrukcji Sklyanina, udało nam się stworzyć metodę pozwalającą obliczyć funkcje korelacji brzegowego modelu XXZ w którym brzegi odziaływują z wzdłużnym polem magnetycznym. Otrzymaliśmy, biorąc granicę pół nieskończonej sieci, reprezentację tzw. bloków elementarnych m sąsiednich operatorów, jako m-wymiarowe całki. Nasze wyniki mają strukutrę zblizoną do modelu periodycznego. Zakończę seminarium przedstawiając kilka przypadków gdy całki się separują i można otrzymać wynik w zwartej formie. Ta praca została wykonana w kolaboracji z N. Kitanine, J-M. Maillet, G. Niccoli, N. Slavnov i V. Terras. |
| 23.03.2007 | --- | --- |
| 16.03.2007 | Jan Dereziński | Open quantum systems and the weak coupling limit, part 4 |
| 9.03.2007 | Jan Dereziński | Open quantum systems and the weak coupling limit, part 3 |
| 2.03.2007 | Jan Dereziński | Open quantum systems and the weak coupling limit, part 2 |
| 23.02.2007 | Jan Dereziński | Open quantum systems and the weak coupling limit, part 1 ABSTRACT: We dedicate these lectures to study several aspects of mathematical description of dynamics of small quantum systems interacting with the environment. In particular we will consider: 1. Dilatations of semigroups. 2. Weak coupling limit for Fiedrichs Hamiltonian - toy-model of open quantum systems 3. Completely positive maps 4. Completely positive semigroups and Lindblad generators 5. Quantum Langevin (stochastic) dynamics as a dilatation of the completely positive semigroup 6. Small quantum system interacting with the (positive temperature) bosonic gas See also: http://www.fuw.edu.pl/~derezins/mars-slides.pdf. STRESZCZENIE: Ten cykl wykladow jest powtorzeniem minikursu, ktory wyglosilem w styczniu b.r. w Marsylii na szkole zimowej Nonequilibrium phenomena in statistical mechanics. Poswiecony jest roznym aspektom matematycznego opisu dynamik malych ukladow kwantowych oddzialujacych z otoczeniem. Oto lista tematow, ktore beda poruszone: 1. Dylatacje polgrup. 2. Granica slabego sprzezenia dla Hamiltonianow Friedrichsa - model-zabawka otwartych ukladow kwantowych. 3. Odwzorowania calkowicie dodatnie (c.p.). 4. Polgrupy c.p. i generatory Lindblada - podstawowy formalizm fenomenologicznego opisu ukladow kwantowych oddzialujacych z otoczeniem. 5. Kwantowa dynamika Langevin'a (stochastyczna) jako dylatacja polgrupy c.p. 6. Maly uklad kwantowy oddzialujacy z gazem bozonow. 7. Granica slabego sprzezenia. 8. Formalizm kanonicznych zwiazkow komutacyjnych. 9. Gaz bozonow o dodatniej gestosci/temperaturze. 10. Maly uklad kwantowy oddzialujacy z gazem bozonow o dodatniej gestosci/temperaturze. Patrz rowniez http://www.fuw.edu.pl/~derezins/mars-slides.pdf. |
| 26.01.2007 | Krzysztof Meissner | Coleman-Weinberg mechanism in the Standard Model |
| 19.01.2007 | --- | --- |
| 12.01.2007 | Ryszard Kostecki | Ponzano-Regge reloaded, part 2 |
| 5.01.2007 | Ryszard Kostecki | Ponzano-Regge reloaded |
| 15.12.2006 | Ryszard Kostecki | Ponzano-Regge model for 2+1 quantum gravity |
| 8.12.2006 | Jacek Wojtkiewicz | On animals, their herds, groups and gangs, or on cluster expansions, part 2 |
| 24.11.2006 | Johannes von Brunnemann | Towards Singularity Avoidance in Loop Quantum Gravity |
| 17.11.2006 | Jerzy Lewandowski | Is the Loop Quantum Gravity program complete? - part 2 |
| 10.11.2006 | Jerzy Lewandowski | Is the Loop Quantum Gravity program complete? |
| 3.11.2006 | Jacek Wojtkiewicz | On animals, their herds, groups and gangs, or on cluster expansions ABSTRACT: The partition function Z is a fundamental object in statistical mechanics and (euclidean) quantum field theory. Often it can be expressed as a sum over geometrical objects, called polymers, contours or animals. Instead of Z itself, one uses its logarithm ("pressure", "free energy"). However, a naive attempt to establish radius of convergence of resulting series gives zero (in the thermodynamic limit). It is necessary to rearrange the series in order to cancel terms with opposite signs. It is a subject of cluster expansions. I will try to present one of many existing proofs of cluster expansion due to R. Dobrushin. (All terms, appearing in the title, are fully legitimated as they appear in original R.D. paper). STRESZCZENIE: Terminy z tytułu nie są nadużyciami, Są bowiem z pracy R. Dobrushina cytatami. Praca ta zajmuje się rozwinięciami Klastrowymi i ich dowodami. Motywacja rozwinięć dana jest takimi argumentami: Suma statystyczna za fundamentalną wielkość słusznie uchodzi, Ale w zastosowaniach często zlogarytmować ją przychodzi. Natomiast gdy zbieżnosci szeregu powstałego się dowodzi, I gdy się do granicy TD przychodzi, To zerowy promień zbieżnosci się otrzymuje, Gdy się zbiezność bezwzględna naiwnie ustanowić próbuje. Trzeba więc wyrazy rozwinięcia przegrupować, Aby człony niejednakowego znaku nawzajem skasować. Tym sie teoria rozwinięć klastrowych zajmuje. Postaram sie pokazać jak dowód R. Dobrushina pracuje. |
| 27.10.2006 | Maciej Dunajski | Solitons and topology |
| 20.10.2006 | Jan Dereziński | Toy models of renormalisation for operators |
| 13.10.2006 | Marcin Domagała | 2+1 Quantum gravity - part II |
| 6.10.2006 | Marcin Domagała | 2+1 Quantum gravity - part I |
| Date | Speaker | Title |
|---|---|---|
| 21.06.2006 | Sylvain Golenia | Positive commutators and the spectrum of Pauli-Fierz Hamiltonian of atoms and molecules ABSTRACT: In this talk we will explain how positive commutators technics can provide some refine informations on the spectrum (absence of eigenvalue, nature of the spectral measure...) of a Pauli-Fierz Hamiltonian for small coupling constants. In a first part, we will show a positive commutator estimate far from the thresholds. In a second part, we will show how to obtain such an estimate at a threshold under a Fermi-golden-rule assumption. We follow the approach of Bach, Frohlich, Sigal, Soffer. |
| 9.06.2006 | Piotr Sułkowski | Dualities in topological quantum string and field theories |
| 5.05.2006 | Laurent Freidel | |
| 28.04.2006 | Jarosław Korbicz | A remark on a group-theoretical formalism for quantum mechanics and the correspondence principle. ABSTRACT: We sketch a group-theoretical framework, based on the Heisenberg-Weyl group, encompassing both quantum and classical statistical descriptions of mechanical systems. We re-define in group-theoretical terms the kinematical arena and the state-space of the system, achieving a unified quantum-classical language and a novel version of the correspondence principle. We also briefly discuss the structure of observables and dynamics within our framework. |
| 21.04.2006 | Sylvain Golenia | Positive commutators and the spectrum of Pauli-Fierz Hamiltonian of
atoms and molecules ABSTRACT: In this talk we will explain how positive commutators technics can provide some refine informations on the spectrum (absence of eigenvalue, nature of the spectral measure...) of a Pauli-Fierz Hamiltonian for small coupling constants. In a first part, we will show a positive commutator estimate far from the thresholds. In a second part, we will show how to obtain such an estimate at a threshold under a Fermi-golden-rule assumption. We follow the approach of Bach, Frohlich, Sigal, Soffer. |
| 7.04.2006 | Jerzy Lewandowski | Spin-Foam as Feynman Graph of Group Field Theory, part II |
| 31.03.2006 | Jerzy Lewandowski | Spin-Foam as Feynman Graph of Group Field Theory, part I |
| 24.03.2006 | Wojciech Kaminski | Spinfoams, quantum groups and topological invariants, part V |
| 17.03.2006 | Wojciech Kaminski | Spinfoams, quantum groups and topological invariants, part IV |
| 10.03.2006 | Wojciech Kaminski | Spinfoams, quantum groups and topological invariants, part III |
| 3.03.2006 | Wojciech Kaminski | Spinfoams, quantum groups and topological invariants, part II |
| 24.02.2006 | Wojciech Kaminski | Spinfoams, quantum groups and topological invariants |