Seminar of Theory of Relativity and Gravitation
2006/2007 | 2007/2008 | 2008/2009 | 2009/2010 | 2010/2011 | 2011/2012 | 2012/2013 | 2013/2014 | 2014/2015 | 2015/2016 | 2016/2017 | 2017/2018 | 2018/2019 | 2019/2020 | 2020/2021 | 2021/2022 | 2022/2023 | 2023/2024 | 2024/2025 | Seminar homepage
2020-03-13 (Friday)
room 1.40, Pasteura 5 at 11:15 
Włodzimierz Piechocki (NCBJ)Quantum BKL scenario
I will present the quantum model of the asymptotic dynamics underlying the Belinski-Khalatnikov-Lifshitz (BKL) scenario. The classical BKL scenario concerns generic singularity of general relativity. The quantum BKL scenario shows that gravitational singularity can be replaced by quantum bounce that presents a unitary evolution of considered gravitational system. Our results suggest that quantum general relativity, to be constructed, has a good chance to be free from singularities.
2020-03-06 (Friday)
room 1.40, Pasteura 5 at 11:15
Anna Nakonieczna (IFT UW)Gravitational collapse involving the dark sector
2020-02-28 (Friday)
room 1.40, Pasteura 5 at 11:15
Andrzej Rostworowski (UJ)Cosmological perturbations in the Regge-Wheeler formalism
I will discuss linear perturbations of the Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmological model in the Regge-Wheeler formalism which is a standard framework to study perturbationsof spherically-symmetric black holes. In particular, I will show that the general solution of linear perturbation equations can be given in terms of two copies of a master scalar satisfying scalar wave equation on the FLRW background (with a Regge-Wheeler/Zerilli type potential) thus representing two gravitational degrees of freedom, and one scalar satisfying a transport type equation representing matter perturbation. It is expected that the Regge-Wheeler formalism can be easily extended to includenonlinear perturbations, akin to the recent work [Phys. Rev. D 96, 124026 (2017)].
2020-01-24 (Friday)
room 1.40, Pasteura 5 at 11:15
Tomasz Smołka (KMMF)Conserved quantities related to (3+1) decomposition of CYK tensors
Conformal Yano-Killing (CYK) tensor is a generalization of Killing vector to anti-symmetric two-form which describes so called hidden symmetries. (3+1) decomposition of CYK tensor enables one to construct charges from initial data in a new, simple and geometric way. I will present the construction and compare it with traditional ADM approach.
2020-01-17 (Friday)
room 1.40, Pasteura 5 at 11:15
Konrad Topolski (FUW)Particle trapping by gravitational waves
In my talk I will present the results of my undergraduate thesis regarding the phenomenon of massive particle trapping by gravitational Bessel beams. In order to present a coherent story, I will introduce a local, Lorentz-covariant gravitational energy tensor, a quadratic function of the gravitational field, using a framework developed by Luke Butcher. It exhibits many desirable properties which shall be mentioned. I will also describe how various gravitational beams can be obtained (invoking the work of Iwo Białynicki-Birula and Zofia Białynicka-Birula), with a special interest in the Bessel beams (works of my thesis advisor Szymon Charzyński and Iwo Białynicki Birula).
2020-01-10 (Friday)
room 1.40, Pasteura 5 at 11:15
Andrzej Królak (IM PAN)Recent observations of gravitational wave signals by LIGO and Virgo detectors
2019-12-13 (Friday)
room 1.40, Pasteura 5 at 11:15
Giacomo Rosati (UWr)Testing quantum spacetime symmetries with gamma-ray-burst neutrinos and photons
We review some models of quantum-gravity-inspired quantum-spacetimes in which relativistic symmetries are modified (deformed or broken) at the Planck scale so that spacetime itself might behave like a dispersive medium for particle propagation (in-vacuo dispersion). We point out the opportunity of testing experimentally this kind of effects through the observations of astrophysical neutrinos, supposedly emitted by gamma-ray-bursts (GRB), and GRB-photons, showing that the same effect could apply over a wide range of energies.
2019-12-06 (Friday)
room 1.40, Pasteura 5 at 11:15
Krzysztof A. Meissner (IFT UW)Conformal Cyclic Cosmology
2019-11-29 (Friday)
room 1.40, Pasteura 5 at 11:15
Armando Cabrera Pacheco (Universität Tübingen)On the role of sequences of manifolds and convergence in general relativity
2019-11-22 (Friday)
room 1.40, Pasteura 5 at 11:15
László András (Wigner RCP)General Relativity experiment with spin polarized particle beams
The magnetic and electric dipole moment of elementary particles turns out to be a rather interesting observable for obtaining experimental indication on possible Beyond Standard Model (BSM) physics. In order to measure charged particle electric dipole moment (EDM), the so-called "frozen spin" storage ring concept was developed in the last decades. It turns out that due to Earth's gravitational field, general relativity (GR) gives a sizable systematic contribution to the EDM observable in a frozen spin storage ring setting. In this talk we give the outline an experimental possibility for a novel test of GR, using this effect.