Research Center for Astronomy

Events

15-20 September 2024

@ Academy of Athens

HERA 24 CONFERENCE

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Tuesday 9 July 2024, 12:00

WEBINAR

The center of mass issue of an extended body moving in a curved spacetime

Georgios Loukes-Gerakopoulos

Astronomical Institute, Czech Academy of Sciences

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Seminars / Webinars

UPCOMING WEΒINAR

Tuesday 9 July 2024, 12:00 (EET)

The center of mass issue of an extended body moving in a curved spacetime

Georgios Loukes-Gerakopoulos

Astronomical Institute, Czech Academy of Sciences

Abstract:

We shall review the problematic of how to define an extended test body in a curved spacetime and focus on the issue regarding its center of mass. We will discuss how an almost century old issue has become again relevant in the era of gravitational wave astronomy. Namely, we shall show how this issue reappears in the case that a stellar compact object inspirals into a supermassive black hole.

 


Past webinar recordings are available here

Past Webinars

Date Speaker Title
25 June 2024 Diego Valencia-Enríquez
Universidad Mariana, Colombia
Orbital Dynamics and Structural Evolution in Barred and Unbarred Disc Galaxy Models
18 June 2024 Francesca Fragkoudi
Institute for Computational Cosmology, Department of Physics, Durham Universitu
Barred galaxies in ΛCDM: Uncovering the formation history and dark matter content of Milky Way-type galaxies
4 June 2024 Athanasios C. Tzemos
RCAAM of the Academy of Athens
Advances in Bohmian Chaos
28 April 2024 Iannis Dandouras
Institut de Recherche en Astrophysique et Planétologie CNRS / Université de Toulouse / CNES, Toulouse, France
Space plasma physics from Moon orbit and from the Moon surface: opportunities provided by the Lunar Gateway programme
24 April 2024 Eugene Vasiliev
Institute of Astronomy, University of Cambridge, UK
Dynamical modelling of barred galaxies
9 April 2024 Francesco Sylos Labini
Enrico Fermi Research Center, Rome, Italy
Rotation curves of the Milky Way and of external galaxies and a new mass model

12 March 2024

Fransisco Gonzalez Montoya
UNAM and University of Leeds
Normally Hyperbolic Invariant Manifolds in the Stormer problem: A generalization of the Unstable Periodic Orbits and its role in the transport in phase space
6 February 2024 Matheus M. A. Paixão
Brazilian Center for Research in Physics
Bohmian Mechanics, chaos, and the Unruh effect
30 January 2024 Henrique Santos Lima
Brazilian Center for Research in Physics
First-principle validation of Fourier’s law: a brief study of classical inertial n-vector models
16 January 2024 Janusz Mlynarczyk
AGH University, Krakow, Poland
Extremely low frequency electromagnetic waves in the Earth-ionosphere waveguide
16 January 2024 A. Burkert
Chair of Theoretical and Computational Astrophysics
Ludwig Maximilians University, Munich
The turbulent dynamics of high-redshift disk galaxies
9 January 2024 A. Nathanail
RCAAM of the Academy of Athens
Short Gamma-ray bursts as binary neutron star mergers, or not?
19 December 2023 I. Contopoulos
RCAAM of the Academy of Athens
Τεχνητή Γενική Νοημοσύνη: Προκλήσεις και Ευκαιρίες
12 December 2023 G. Korkidis
University of Crete
A new probe of Cosmology
28 November 2023 Johan H. Knapen
IAC Tenerife, Spain
Uncovering galaxy history through deep imaging and machine learning
21 November 2023 Sophia Stuber
Max-Planck-Institut für Astronomie, Heidelberg, Germany
Molecular Gas Morphologies in Nearby Main Sequence Galaxies from PHANGS
7 November 2023 Jairo Méndez Abreu
Universidad de La Laguna/Instituto de Astrofísica de Canarias
The barred galaxy population in the distant Universe
31 October 2023 M. Bureau
University of Oxford, UK
Probing the Invisible: Weighing Supermassive Black Holes with ALMA
24 October 2023 S. Hozumi
Shiga University, Otsu, Japan
The origin of the bar properties generated by the bar instability in flat stellar disks
11 July 2023 M. Opher
Astronomy Department, Boston University, Boston, MA, United States
The Heliosphere, a case of a Habitable Astrosphere
29 June 2023 H. Skokos
University of Cape Town, S. Africa
Numerical approaches for investigating the chaotic behavior of multidimensional Hamiltonian systems
20 June 2023 D. Christodoulou
University of Massachussets
A Compendium of Research Projects from the Past Year
23 May 2023 K. Founta
University of Thessaly
Modelling and simulating a combat: Battle of Salamis
16 May 2023 K. Dialynas
Center of Space Research & Technology, Academy of Athens
The science of large scale heliosphere and missions that made it possible
9 May 2023 M. Sormani
Universität Heidelberg
The Galactic centre: structure, dynamics and star formation
4 Apr 2023 E. Floratos
Academy of Athens
Arnol'd cat map lattices

28 Mar 2023

P. Erwin
Max-Planck-Institute for Extraterrestrial Physics
Composite Bulges: A Partial Zoology of Beasts that Live at Centers of Galaxy Disks
9 Mar 2023

M. Romero-Gomez
Departament de Fisica Quantica i Astrophysica, University of Barcelona

Dynamics with Gaia in the Maggelanic Clouds
31 Jan 2023

Athanasios C. Tzemos
RCAAM of the Academy of Athens

Ergodicity and Born's rule in multiqubit Bohmian systems
10 Jan 2023

Tassos Bountis
CRANS-Center for Research and Applications in Nonlinear Systems, University of Patras

Long range interactions enhance stability in 1-D Hamiltonian lattices

18 Oct

2022

Thomas Kotoulas
Aristotle University of Thessaloniki

Two-parametric families of orbits created by three-dimensional galactic-type potentials
14 Oct 2022

George Contopoulos
Academy of Athens

(Spirals and bars in galaxies: One-day workshop)

The spiral arms of galaxies (29:51)

14 Oct 2022

Kanak Saha
Inter-University Centre for Astronomy and Astrophysics, India

(Spirals and bars in galaxies: One-day workshop)

Revisiting spiral structures in galaxies (1:21:30)

14 Oct 2022

Lia Athanassoula
Laboratoire d’Astrophysique de Marseille (LAM), Marseille, France

(Spirals and bars in galaxies: One-day workshop)

Understanding the Formation and Evolution of Bars using Simulations (2:24:23)

14 Oct 2022

Christos Efthymiopoulos
Department of Mathematics,
University of Padova, Italy

(Spirals and bars in galaxies: One-day workshop)

Manifolds and spirals under multiple pattern speeds (3:41:07)

14 Oct 2022 P. Grosbol
European Southern Observatory (ESO),
Munich, Germany

(Spirals and bars in galaxies: One-day workshop)

Interaction between spirals and bars in disk galaxies  (4:33)

14 Oct 2022 M. Harsoula
Research Center for Astronomy and Applied Mathematics, Academy of Athens

(Spirals and bars in galaxies: One-day workshop)

The building blocks of the spiral arms in galaxies (1:00:15)

14 Oct 2022 T. Naab
Max-Planck Institut fuer Astrophysik, (MPA),
Munich, Germany

(Spirals and bars in galaxies: One-day workshop)

The formation of galactic star cluster populations (1:45:06)   

14 Oct 2022 P.A. Patsis
Research Center for Astronomy and Applied Mathematics, Academy of Athens

(Spirals and bars in galaxies: One-day workshop)

Open questions about the association of observed structures and orbits in galactic disks (2:21:15)

8 Sep 2022 Malcolm Hillebrand
Department of Mathematics and Applied Mathematics University of Cape Town
Biophysical chaos: Bubbles in DNA molecules
20 Jul 2022 Suraj Dhiwar
Prime Minister's Research Scholar, Department of Physics, IIT Guwahati, India
Star Formation Quenching in L* Ellipticals
18 Jul 2022 Samik Mitra
Prime Minister's Research Scholar, Department of Physics, IIT Guwahati, India
Properties of general relativistic magneto-hydrodynamics accretion flows around black holes in steady-state limit (Watch here)
12 Jul 2022 Christos Efthymiopoulos
University of Padova, Department of Mathematics
The information approach to the interpretation of quantum mechanics (Watch here)
5 Jul 2022 Kanak Saha
Inter-University Centre for Astronomy and Astrophysics, Pune, India
Growth and survival of bars in disk galaxies (Watch here)
28 Jun 2022 Georgios Loukes-Gerakopoulos
Astronomical Institute of the CAS, Czech Republic
Celestial Mechanics of Extreme Mass Ratio Inspirals (Watch here)
14 Jun 2022 Matthaios Katsanikas
Research Center for Astronomy and Applied Mathematics, Academy of Athens
Stickiness in 3D rotating galactic potentials (Watch here)
9 Jun 2022 Makrina Agaoglou
Instituto de Ciencias Matematicas, Madrid, Spain
Transport processes on a Potential Energy Surface with four wells, four index-1 saddles and an index-2 saddle (Watch here)
24 May 2022 Susanna Parenti
Institut d'Astrophysique Spatiale, France
Validation of a wave heated 3D MHD coronal-wind model using Polarized Brightness and EUV observations (Watch here)
17 May 2022 Konstantina Zouloumi
Research Center for Astronomy & Applied Mathematics & Department of Astrophysics, Astronomy and Mechanics, University of Athens
NAAF determination of the multiple pattern speeds and the manifolds in a simulation of a barred spiral galaxy (Watch here)
3 May 2022 Antonios Tsokaros
University of Illinois at Urbana-Champaign, USA
Numerical general relativity and astrophysics in the era of multimessenger astronomy (Watch here)
18 Apr 2022 Stavros Pastras
Research Center for Astronomy and Applied Mathematics, Academy of Athens
& Department of Physics, Section of Astrophysics, Astronomy and Mechanics, University of Athens
Gasflows in barred spiral galaxies by means of two different hydrocodes (Watch here)
12 Apr 2022 Spyridon Aleiferis
UK Atomic Energy Authority, Culham Science Centre, Abingdon, UK
Taming of the stars: how to control fusion plasmas (Watch here)
31 Mar 2022 Evangelos Melas
University of Athens, Department of Economics
Asymptotic symmetries and representation theory in General Relativity in three and four space-time dimensions (Watch here)
29 Mar 2022 Georgios Doulis
Institute of Theoretical Physics, University of Jena, Germany
Entropy as shock indicator in neutron star merger simulations (Watch here)
15 Mar 2022 Dimitris Stamatellos
Jeremiah Horrocks Institute for Mathematics, Physics & Astronomy, University of Central Lancashire, Preston, UK
The formation and evolution of disc-instability planets (Watch here)
10 Mar 2022 Damianos Iosifidis
Aristotle University of Thessaloniki
Perfect Hyperfluids (Watch here)
8 Mar 2022 Antonios Nathanail
University of Athens, Department of Physics
Still observing light from the binary neutron star merger first detected in 2017 (Watch here)
3 Mar 2022 Karnesis Nikolaos
Aristotle University of Thessaloniki, School of Physics
Detecting Gravitational Waves from space (Watch here)
22 Feb 2022 Athanasios C. Tzemos
Research Center for Astronomy and Applied Mathematics of the Academy of Athens
Chaos and Bohmian Quantum Potential (Watch here)
15 Feb 2022 Ioannis Contopoulos
Research Center for Astronomy and Applied Mathematics of the Academy of Athens
Quantum Interference: reality or an illusion of the detector? (Watch here)
8 Feb 2022 Charis Anastopoulos
Department of Physics, University of Patras
Gravitational effects in macroscopic quantum systems (Watch here)
1 Feb 2022 Konstantinos N. Gourgouliatos
Department of Physics, University of Patras
Magnetic Field Evolution in Neutron Star Crusts: Hall effect and beyond ( Watch here)
18 Jan 2022 Athanasios C. Tzemos
Research Center for Astronomy and Applied Mathematics of the Academy of Athens
Born's rule in the case of 3 entangled Bohmian qubits (Watch here)
11 Jan 2022 Constantinos Kalapotharakos
University of Maryland and Astrophysics Science Division, NASA/Goddard Space Flight Center, USA
Interpreting the Thermal and Non-Thermal High-Energy Emission in Multipolar Field Pulsar Magnetospheres (Watch here)
14 Dec 2021 Thorsten Naab
Max-Planck-Institute for Astrophysics, Garching, Germany
The GRIFFIN project - towards realistic simulations of galactic star cluster populations (Watch here)
7 Dec 2021 Ivan Minchev
Leibniz-Institut für Astrophysik Potsdam (AIP)
Modeling the Galactic disk in the age of Gaia (Watch here)
30 Nov 2021 Edoardo Legnaro
Research Center for Astronomy and Applied Mathematics of the Academy of Athens and University of Thessaloniki
Analytic Theory for Secular Lunisolar Resonances (Watch here)
9 Nov 2021 Dimitri A. Gadotti
ESO – European Southern Observatory
Nuclear discs in external galaxies and the Milky Way: building "bulges" without mergers (Watch here)
26 Oct 2021 Demosthenes Kazanas
NASA Goddard Space Flight Center, Corresponding Member of the Academy of Athens
Gravity beyond Einstein? Yes, but in which direction? (Watch here)
13 Jul 2021 Dimitris Christodoulou
University of Massachusetts
Major-Body Clustering in the Solar System (Watch here)
24 Jun 2021 Panos A. Patsis
Research Center for Astronomy and Applied Mathematics of the Academy of Athens
Building blocks of 3D, X-shaped bulges and thick spirals
(Watch here)
8 Jun 2021 George Contopoulos
Research Center for Astronomy and Applied Mathematics of the Academy of Athens
Μια συνοπτική έκθεση της Φιλοσοφίας της Φυσικής και των Μαθηματικών
(Διαθέσιμη μαγνητοσκοπημένη)
1 Jun 2021 Christos Efthymiopoulos
Department of Mathematics Tullio Levi-Civita, University of Padua
(Work in collaboration with Rita Mastroianni)
Secular dynamics for exoplanetary systems with two planets in mutually inclined orbits
(Watch here)
13 May 2021 Athanasios C. Tzemos
Research Center for Astronomy and Applied Mathematics of the Academy of Athens
Born's Rule in the case of two entangled Bohmian qubits
(Watch here)
22 Apr 2021 Costis Gontikakis
Research Center for Astronomy and Applied Mathematics of the Academy of Athens
Study of the emission measure during a solar flare observed with IRIS spectrograph (Watch here)

Seminars in 2020

Date Speaker Title
3 Mar 2020 Anastasios Anastasiadis
National Observatory of Athens / IAASARS
Unveiling Current Challenges in Space Weather Forecasting: The SAWS-ASPECS tool
25 Feb 2020 Vasileios Basios
Université Libre de Bruxelles, Interdisciplinary Centre for Nonlinear Phenomena & Complex Systems (Cenoli-ULB) & Département de Physique des Systèmes Complexes et Mécanique Statistique
Labyrinth Chaos: Conservative, non-Hamiltonian Chaos without Attractors
18 Feb 2020 Elias Koulouridis
National Observatory of Athens / IAASARS
Tracing the Universe: X-ray surveys and cosmology
11 Feb 2020 Costis Gontikakis
Research Center for Astronomy and Applied Mathematics of the Academy of Athens
Moss, the trace of hot loops in EUV, an ongoing research
28 Jan 2020 Athanassios C. Tzemos
Research Center for Astronomy and Applied Mathematics of the Academy of Athens
Chaos and ergodicity in the trajectories of two entangled Bohmian qubits
21 Jan 2020 George Dimopoulos
National Observatory of Athens
Coronal properties of Sy I Active Galaxies
14 Jan 2020 Panos A. Patsis
Research Center for Astronomy and Applied Mathematics of the Academy of Athens
Some open issues in Galactic Dynamics and the contribution of Image Processing in resolving them

A list of all previous seminars from 2008 to 2020 is available here.

Seminars List booklet

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