[Note: This web-page is being updated continuously: current status: 26.09.15] LOCATION and TIME: Observatoire astronomique de Strasbourg, Universite de Strasbourg, CNRS UMR 7550, Sept. 21st - 25th 2015 Below are provided 1.BACKGROUND/MOTIVATION 2.HOW TO REGISTER 3.PARTICIPANTS 4.HOTELS 5.PROGRAMME 6.PHANTOM WIKI
ORGANISERS: Benoit Famaey (Strasbourg) and Pavel Kroupa (Bonn)
1.BACKGROUND / MOTIVATION: Galaxy-scale data seem to be in accordance with the hypothesis that the extrapolation of Newtonian gravitation by orders of magnitude below the Solar system space-time curvature breaks down completely, and that collisionless astronomical systems behave according to space-time scale-invariant dynamics, as postulated by Mordehai Milgrom (2015). The classical theories of dynamics and gravitation underlying this symmetry, often referred to as MOND theories, show a richer dynamical behaviour with new phenomena which appear non-intuitive to a Newtonian mind. Very successful analytical results have been obtained in this dynamics framework, such as accounting for the hitherto not understood properties of polar-ring galaxies (Lueghausen et al. 2013), accounting for the Bullet cluster (Angus, Fmaey & Zhao 2006; Angus & McGaugh 2008) and the properties of disk galaxies (MOND reviews by Scarpa 2006; Famaey & McGaugh 2012;Trippe 2014) and elliptical galaxies (Sanders 2000; Milgrom & Sanders 2003; Scarpa 2006).
But little understanding of the dynamical behaviour of live Milgromian systems has been gathered. Live calculations, i.e. simulations of galaxies, are required in order to test, to possibly refine or to falsify this approach. The implications for fundamental physics are major in any case!
A series of Milgromian-dynamics workshops is planned to begin remedying this situation.
With this first “Phantom of Ramses” (PoR) meeting, the aim is to bring together the pioneers who have been daring footsteps into applying Milgromian dynamics to simulate live galaxies. First simulations of galaxies within MOND have been achieved with the first Milgromian Nbody code without gas (Brada & Milgrom 1999). Tiret & Combes (2007) re-visited this problem with their own code. The PhD thesis of Tiret is available here (in French). For spheroidal geometries MOND simulations have become possible with the NMODY code by Nipoti, Londrillo & Ciotti (2007), see e.g. the application of this code to the phase-transition of spheroidal systems on radial orbits (Wu & Kroupa 2013). A MOND code has also been developed for studies of cosmological structure formation by Ilinares, Knebe & Zhao (2008). While being highly successful in their ability to represent observed galaxies, all of these attempts have died-off due to a lack of long-term sustainability.
Now much more involved and more numerous studies has become possible with the first publicly available Milgromian dynamics computer code including star formation, i.e. baryonic physics (Lueghausen, Famaey & Kroupa 2015) with which even full-scale simulations of cosmological structure formation have become achievable, PoR being an official patch to Teyssier’s RAMSES code. A similar computer code (RAyMOND) has been developed independently by a Chilean research group (Candlish, Smith & Fellhauer 2015).
Because non-linear Milgromian dynamics is largely non-intuitive for researchers trained to think within the framework of linear Newtonian gravitation, this group of pioneers needs to find the chance to discuss, in as great depth as is required, the issues arising with initialising, setting-up and evolving Milgromian galaxies in virial equilibrium, including gas dynamics and star formation. The first scientific results which have already been achieved with the PoR code will be discussed at this occasion, but research related to Milgromian dynamics (e.g. by adoption of zeroth-order approximations by adding dark matter particles to Newtonan systems) will also be discussed.
The meeting will take place at the Observatoire astronomique de Strasbourg. We are planning a whole week for this event, whereby there will be one to two (at most three) presentations per day interrupted with long discussion breaks to dwell upon problems that have been encountered and that may need solutions. Also, the breaks are intended to allow new persons to learn using PoR. The meeting will take place in the *MEETING ROOM* (with a capacity of about 20) at the Observatoire, and the presentations can be of any duration, but must have a break after the first 45 minutes if longer. After the last presentation each day discussions may continue at will, and Strasbourg offers many excellent culinary opportunities for the evening entertainments.
2.HOW TO REGISTER / IF INTERESTED: Please register by sending an e-mail to Benoit Famaey <benoit.famaey_at_astro.unistra.fr> and to Pavel Kroupa <pavel_at_astro.uni-bonn.de>. Note that this meeting does not have invited talks. The attendance is limited to 20.
3.PARTICIPANTS (preliminary): Garry Angus (Brussel, Belgium) Indranil Banik (St. Andrews, UK) Christian Boily (Strasbourg, France) Joerg Dabringhausen (remotely from Concepcion, Chile) Benoit Famaey (Strasbourg, France) [SOC] Martin Feix (Paris, France) Hector Flores (Paris, France) Alistair Hodson (St. Andrews, UK) Rodrigo Ibata (Strasbourg, France) Tereza Jerabkova (Praha, Czech Rep.) Pavel Kroupa (Bonn, Germany) [SOC] Fabian Lüghausen (Bonn, em.; tbc) Marcel Pawlowski (Cleveland, USA) Florent Renaud (Surrey, UK) Jean-Babtiste Salomon (Strasbourg, France) Ingo Thies (Bonn, Germany) Guillaume Thomas (Strasbourg, France) Yanbin Yang (Pairs, France) HongSheng Zhao (St. Andrews, UK)
Conference Photo (24.09.2015): Left to right: Yanbin Yang, Indranil Banik, Ingo Thies, Guillaume Thomas, Garry Angus, Jean-Babtiste Salomon, Tereza Jerabkova, HongSheng Zhao, Rodrigo Ibata, Marcel Pawlowski, Hector Flores, Alistair Hodson, Florent Renaud, Benoit Famaey, Fabian Lueghausen, Pavel Kroupa
5.PROGRAME: The programme, abstracts and list of participants are available here as a pdf file: PoR_Programme.pdf PROGRAM (with downloadable presentations): First Workshop on Progress in Modelling Galaxy Formation and Evolution in Milgromian dynamics — first results achieved with the Phantom of Ramses (PoR) code. At the Observatoire astronomique de Strasbourg, 21.09.-25.09.2015. PoR-code talks are scheduled for the afternoons allowing for discussion and learning time. A few scientific talks relevant to the mass-deficit problem are scheduled for the mornings. ******* Sunday, 20th September evening, approximately 18:00- Meet for drink and food at Au Brasseur ******* Monday, 21st September 10:00 MORNING COFFEE 10:30 Welcome/Introduction/First presentation and discussion: Setting the scene: 1. Kroupa_PoR.pdf: Why is the dark-matter approach ill-fated? (Pavel Kroupa) 2. Famaey.pdf: The basics of Milgromian dynamics/MOND (Benoit Famaey) LUNCH (12:15-14:45) 15:00-16:15 1. Lueghausen_PoR.pdf: The PoR code (Fabian Lueghausen) 2. Thies_PoR.pdf: Setting up a stable disc galaxy in PoR (Ingo Thies) 16:30 AFTERNOON TEA 17:00-18:00 Open Discussion ******* Tuesday, 22nd September 10:00 MORNING COFFEE 10:45-11:15 (30 minutes) Angus_PoR.pdf: The DiskMass Survey’s implications for MOND, CDM and itself (Garry Angus) LUNCH (12:15-14:45) 14:45-15:15 (30 minutes) Banik.pdf: The External Field Effect In QUMOND: Application To Tidal Streams (Indranil Banik) 16:10 AFTERNOON TEA 16:30 Thomas_PoR.pdf: Simulating Tidal Streams with PoR (Guillaume Thomas) PoR Movie (dSph Sgr, slide 19 in presentation): YouTubelink 17:00-18:00 Open Discussion - decision to set up PhantomWIKI ******* Wednesday, 23rd September 10:00 MORNING COFFEE 10:45-11:15 Yang_PoR.pdf: (30 minutes) Reproducing properties of MW dSphs as descendants of DM-free TDGs (Yanbin Yang) MEETING PHOTO (12:15) LUNCH (12:20-14:45) 14:15-14:45 Angus2_PoR.pdf: The sub-subhalo connection to M31’s plane of satellites (Garry Angus) 14:45-15:15 Pawlowski_PoR.pdf: (30 minutes) Small-scale problems of cosmology and how modified dynamics might address them (Marcel Pawlowski) 16:00 AFTERNOON TEA 16:30 Renaud_PoR.pdf: Gravitation-triggered star formation in interacting galaxies (Florent Renaud) 17:30-18:00 Open Discussion 18:30-- Workshop dinner at Au Brasseur ******* Thursday, 24th September 10:30 MORNING COFFEE 10:45-11:15 Hodson_PoR.pdf: (30 minutes) EMOND (Extended MOND) and effective galaxy cluster masses (Alistair Hodson) 11:30-12:00 Preliminary results on QMOND forces between point masses (HongSheng Zhao) LUNCH (12:15-14:45) 14:45-15:15 Salomon_PoR.pdf: The tangential motion of the Andromeda System (Jean-Babtiste Salomon) 15:15-15:45 Dabringhausen_PoR.pdf: Early-type galaxies in Milgromian dynamics (Joerg Dabringhausen, remotely from Concepcion, Chile) 16:15 AFTERNOON TEA 16:45-17:15 Banik2_PoR.pdf: Evidence for Dynamical Heating in The Local Group (Indranil Banik) 17:15-18:00 Open Discussion ******* Friday, 25th September 10:00 MORNING COFFEE 10:30-12:00 Kroupa_IMF_Strasbrourg.pdf Main Seminar of the Observatory: Is the stellar IMF a probability distribution function, or is star formation highly regulated? (Pavel Kroupa) LUNCH (12:15-14:45) 15:00 Final discussion and FAREWELL
6.PHANTOM WIKI PhantomWIKI This wiki is dedicated to supporting the research making use of the “Phantom of RAMSES” (PoR) patch.