Center for Theoretical Physics

About: Center for Theoretical Physics is a facility organization based out in Warsaw, Poland. It is known for research contribution in the topics: Gamma-ray burst & Accretion (astrophysics). The organization has 68 authors who have published 112 publications receiving 1086 citations. The organization is also known as: Centrum Fizyki Teoretycznej PAN & Centrum Fizyki Teoretycznej Polskiej Akademii Nauk.

VIPERS: Stellar population properties of early-type galaxies

Abstract: 1. Center for Theoretical Physics, Al. Lotnikow 32/46, 02-668 Warsaw, Poland; 2. National Center for Nuclear Research, ul. A. Soltana 7, 05-400 Otwock, Poland; 3. INAF Istituto di Astrofisica Spaziale e Fisica Cosmica Milano, via Bassini 15, 20133 Milano, Italy; 4. Astronomical Observatory of the Jagiellonian University, Orla 171, 30-001 Cracow, Poland; 5. The VIPERS Team coauthors are presented at the end of this proceedings

An Operational Notion of Classicality Based on Physical Principles

Abstract: Abstract One of the basic observations of the classical world is that physical entities are real and can be distinguished from each other. However, within quantum theory, the idea of physical realism is not well established. A framework to analyse how observations in experiments can be described using some physical states of reality was recently developed, known as ontological models framework. Different principles when imposed on the ontological level give rise to different theories, the validity of which can be tested based on the statistics generated by these theories. Using the ontological models framework, we formulate a novel notion of classicality termed ontic-distinguishability, which is based upon the physical principles that in classical theories extremal states are physical states of reality and every sharp measurement observes the state of the system perfectly. We construct a communication task in which the success probability is bounded from above for ontological models satisfying the notion of ontic-distinguishability. Contrary to previous notions of classicality which either required systems of dimension strictly greater than two or atleast three preparations, a violation of ontic-distinguishability can be observed using just a pair of qubits and a pair of incompatible measurements. We further show that violation of previously known notions of classicality such as preparation non-contextuality and Bell’s local causality is a violation of ontic-distinguishability.

Probing the accretion disk - jet connection via instabilities in the inner accretion flow. From microquasars to quasars

Abstract: We present various instability mechanisms in the accreting black hole systems which might indicate at the connection between the accretion disk and jet. The jets observed in microquasars can have a persistent or blobby morphology. Correlated with the accretion luminosity, this might provide a link to the cyclic outbursts of the disk. Such duty-cycle type of behavior on short timescales results from the thermal instability caused by the radiation pressure domination. The same type of instability may explain the cyclic radioactivity of the supermassive black hole systems. The somewhat longer timescales are characteristic for the instability caused by the partial hydrogen ionization. The distortions of the jet direction and complex morphology of the sources can be caused by precession of the disk-jet axis.

TGFT condensate cosmology as an example of spacetime emergence in quantum gravity

Abstract: We summarize the main ideas behind TGFT condensate cosmology and sketch the technical steps that bring from the fundamental theory to the effective cosmological dynamics. This framework is presented as an explicit illustration of (and possibly a general template for) the emergence of spacetime from non-spatiotemporal quantum entities in quantum gravity, and the many aspects involved in it.

Dynamics Close to the Glass Transition

Abstract: In spite of enormous efforts, the theoretical understanding of the phenomenon referred to as a glass transition is still fragmentary. Laboratory and computer experiments on supercooled liquid and glass properties close to the transition temperature (T g) show how important a role is played, in these materials, by local geometrical arrangements of constituent particles. In this lecture I shall outline a particular theory of glass transition phenomena focusing on a new dynamical concept — the rheological stress — used to account for several important non-equilibrium properties of a glass and its parent supercooled liquid close to the glass transition T g.