Cosmo-pl

cosmo-pl@cosmo.torun.pl

118 discussions

the Universe is old and old age caught up with Allan Sandage :(
by Boud Roukema 19 Nov '10

19 Nov '10

hi everyone, I think I heard at least one conference talk by Sandage. Some of the more senior people here may have known him better. I'll just quote the Wikipedia summary for the younger people among us: Allan Rex Sandage (born June 18, 1926 in Iowa City, Iowa, died November 13, 2010) was an American astronomer. He was Staff Member Emeritus with the Carnegie Observatories in Pasadena, California. He is best known for determining the first reasonably accurate value for the Hubble constant and the age of the universe. http://en.wikipedia.org/wiki/Allan_Sandage pozdr boud

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Postdoc & PhD positions: cosmocoffee many + Dark Cosmology Centre/Niels Bohr Institute
by Boud Roukema 17 Nov '10

17 Nov '10

hi cosmo-pl, There are a lot of cosmology postdoc/PhD announcements that have been recently posted at http://cosmocoffee.info/viewforum.php?f=8 and here's one for Copenhagen. Good luck to the younger generation! pozdr boud ---------- Forwarded message ---------- > Date: Wed, 17 Nov 2010 14:43:23 +0100 > From: Michelle Cumming L?kkegaard <mcl ... > > Subject: Postdoc & PhD positions - Dark Cosmology Centre / Niels Bohr Institute > > > -- Please share widely with your students and colleagues -- > > The Dark Cosmology Centre (DARK), located at the Niels Bohr Institute, University of Copenhagen, announces the following positions: > > Sophie and Tycho Brahe Fellow - prize postdoctoral fellowships, joint with the Texas Cosmology Center (deadline 01 December 2010) > http://dark.nbi.ku.dk/jobs/brahe-fellowships/ > > DARK Fellows - independent postdoctoral fellowships (deadline 01 December 2010) > http://dark.nbi.ku.dk/dark-fellowships/ > > DARK PhD Admissions and Funding - several positions starting in 2011 (deadline 20 December 2010) > http://dark.nbi.ku.dk/jobs/dark-phd/ > > Space Science Center also has post doc and PhD positions available: http://space.ku.dk/jobs > > > Regards, -- > Michelle Cumming L?kkegaard, Centre Coordinator > Dark Cosmology Centre > Niels Bohr Institute, University of Copenhagen > Juliane Maries Vej 30 > 2100 Copenhagen DENMARK > > mcl at dark-cosmology.dk > +45 3532 5933 > http://www.dark-cosmology.dk

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cosmo meetings northern summer 2010
by Boud Roukema 18 Jun '10

18 Jun '10

Witam cosmo-pl, As usual, there are many cosmo meetings in Europe this northern summer. :) This is slightly edited from two French cosmo/extragalactic mailing lists messages. pozdr boud > ---------- Forwarded message ---------- > Date: Mon, 29 Mar 2010 09:36:20 +0200 > Subject: Diffusion PNCG - mess n° 23 (fwd) > Date: Wed, 19 May 2010 18:59:46 +0200 > Subject: Diffusion PNCG - mess n° 25 1. X?me école de cosmologie 5 - 10 July 2010 in Cargese, Corsica http://www.cpt.univ-mrs.fr/~cosmo/EC2010/EcoleLuminy10.html 2. symposium ?Fundamental Frontiers of Physics" 6 to 9 July, 2010, Paris http://ffp11.gie.im 3. The 14th Paris Cosmology Colloquium 2010 - Chalonge Thursday 22, Friday 23 and Saturday 24 JULY 2010 http://chalonge.obspm.fr/colloque2010.html 4. 35th International Conference on High Energy Physics 22 - 28 July, Paris. http://www.ichep2010.fr/ 5. 8th International Conference on Identification of Dark Matter Montpellier, July 26-30th 2010. http://www.lpta.univ-montp2.fr/idm2010 6. New Directions in Modern Cosmology from 27 Sep 2010 through 1 Oct 2010 http://www.lc.leidenuniv.nl/lc/web/2010/412/info.php3?wsid=412 ----------------------------------------------------------------------- 1. X?me école de cosmologie Nous avons le plaisir de vous annoncer la tenue de la dixi?me école de cosmologie intitulée "Le fond diffus cosmologique ? haute résolution angulaire". Elle se déroulera la semaine du 5 au 10 juillet 2010 ? l'IESC (Carg?se). Avec le lancement réussi du satellite Planck, une nouvelle fen?tre d'?observation s?ouvre en cosmologie. L'objectif scientifique de cette école est de montrer comment cette nouvelle génération de données va permettre la recherche de signatures nouvelles caractérisant les mod?les d'univers primordial. Il ne s?agira pas de traiter les données de Planck, qui ne seront pas publiques ? cette époque, mais d?'explorer les avancés théoriques et phénoménologiques. On présentera la physique du fond diffus cosmologique, en insistant en particulier sur les aspects nouveaux, les plus pertinents pour la confrontation des théories aux observations. Les cours principaux seront assurés par N. Aghanim (IAS) - J.F. Cardoso (LTCI) - A.Challinor (DAMTP) - P. Creminelli (ICTP) - E. Komatsu (TCC) - J. Lesgourgues (LAPTH) - S. Prunet (IAP) - J.-P. Uzan (IAP). Ils seront enrichis par des séminaires/cours annexes, des discussions et des débats contradictoires. siteweb : http://www.cpt.univ-mrs.fr/~cosmo/EC2010/EcoleLuminy10.html NB : Le nombre de places étant limité, les intéressés sont priés de s'y inscrire au plus vite pour que l'on puisse prévoir une logistique adéquate. Les organisateurs F. Bernardeau (CEA/DSM/IPhT) - R. Triay (CPT) - F. Vernizzi (CEA/DSM/IPhT) ----------------------------------------------------------------------- 2. symposium ?Fundamental Frontiers of Physics" The 11th annual international meeting ?Fundamental Frontiers of Physics? will take place in Paris, France from 6 to 9 July, 2010. The deadline for submission of an abstract is the 15th of June and for early registration to ?Fundamental Frontiers of Physics? is the 25th of June, 2010. The Symposium develops around five themes: 1. Big Bang Cosmology / Dark Energy 2. Dark Matter/Astroparticles 3. Particle physics and Fundamental Interactions 4. From Intrication to Quantum Information and Quantum Gas 5. Epistemology, History of Physics Parallel sessions will be organized as mini-workshops consisting mostly of twenty minutes oral presentations. Scientific Committee A. Aspect, Institut d?Optique (Palaiseau) P. Binétruy, APC, Paris Diderot University E. Brezin, ENS (Paris) F. Combes, LERMA (Obs. Paris) J. Iliopoulos, ENS ( Paris) J. Kouneiher, University of Nice/IUFM and LUTH (Obs. Paris) M. Lachi?ze-Rey, APC, Paris Diderot University J. A. Madore, University of Orsay J.-J. Szczeciniarz, HPS, Paris Diderot University Please visit the website of the conference for all relevant information http://ffp11.gie.im ----------------------------------------------------------------------- 3. The 14th Paris Cosmology Colloquium 2010 Ecole Internationale d'Astrophysique Daniel Chalonge THE STANDARD MODEL OF THE UNIVERSE: THEORY AND OBSERVATIONS George Smoot Nobel Prize of Physics and Daniel Chalonge Medal Thursday 22, Friday 23 and Saturday 24 JULY 2010 at the parisian campus of Paris Observatory (HQ), in the historic Perrault building. The Conference is within the astrofundamental physics spirit of the Chalonge School, on recent observational and theoretical progress on the CMB, Inflation, astrophysical dark matter, dark ages, dark energy, and the theory of the early universe with predictive power. In summary, the aim of the meeting is to put together real cosmological data and hard theory predictive approach connected to them in the framework of the Standard Model of the Universe. Topics: Observational and theoretical progress in the CMB, astrophysical dark matter, dark energy, dark ages . Large and small scale structure formation. Inflation in connection with the CMB and LSS data, slow roll and fast roll inflation, quadrupole suppression and initial conditions, low CMB multipoles. CMB polarization. Neutrinos in cosmology. The Meeting is open to all scientists interested in the subject. All Informations about the meeting and registration to it are displayed at : http://chalonge.obspm.fr/colloque2010.html Early Registration is strongly encouraged The format of the Meeting is intended to allow easy and fruitful mutual contact and communication. Sessions last for three full days in the beautiful parisian campus of Observatoire de Paris (built on orders from Colbert and to plans by Claude Perrault from 1667 to 1672). All sessions take place in the historic Perrault building ("Bâtiment Perrault") of Observatoire de Paris HQ, under the portraits of Laplace, Le Verrier, Lalande, Arago, Delambre and Louis XIV. An exhibition will retrace the 19 years of activity of the Chalonge School and George Smoot participation to the School along these 19 years. Informations on the previous Paris Cosmology Colloquia and of the school events are available athttp://chalonge.obspm.fr (lecturers, lists of participants, lecture pdf files and photos during the Colloquia). Chalonge.Ecole(a)obspm.fr http://chalonge.obspm.fr/ ----------------------------------------------------------------------- 4. 35th International Conference on High Energy Physics La 35?me Conférence Internationale de Physique des Hautes Energies, la plus importante au monde dans cette spécialité, aura lieu cet été en France, du 22 au 28 juillet ? Paris. A noter que les astroparticules et la cosmologie y seront largement représentées dans une session dédiée et dans les exposés pléniers. Site web : http://www.ichep2010.fr/ ----------------------------------------------------------------------- ----------------------------------------------------------------------- 5. 8th International Conference on Identification of Dark Matter This is the second circular announcing the *** 8th International Conference on Identification of Dark Matter *** that will be held in Montpellier, July 26-30th 2010. We are glad to announce that we will extend abstract submission until MAY 30th 2010 Please refer to http://www.lpta.univ-montp2.fr/idm2010 for further information on travel and accommodation, registration, payments, and abstract submission. See also at the end of this email. We encourage abstract submission from graduate students and posdoctoral fellows. We would appreciate if you could bring this announcement to their attention, and diffuse it to your scientific communities and research departments. Looking forward to seeing you in Montpellier, The local organizing committee Please feel free to contact us if you have questions regarding IDM 2010 (idm2010com(a)lpta.univ-montp2.fr). ----------------------------------------------------------------------- 6. New Directions in Modern Cosmology New Directions in Modern Cosmology from 27 Sep 2010 through 1 Oct 2010 Scientific organizers: T.M. Nieuwenhuizen, ITFA, UvA, R.E. Schild, Harvard CfA F. Sylos Labini, Enrico Fermi Center, Rome R. Durrer, Univ Geneva Aim and description This workshop concentrates on the discussion of recent cosmological observations which present challenges to the standard LCDM model. These observations include: the large scale flows, the sizes and amplitude of galaxy large scale structures, the systematic effects biasing the analysis of CMB data and the lack of large-angle correlations, the anisotropy of the Hubble flow, the evolution of galaxy size, and the failure to find the sub-halo building blocks left over from the primordial fluctuation spectrum. Last and not least, it is disturbing that in the LCDM model 95% of the Universe have not been observed 'directly'. While each of these observations can be seen as an anomaly that the model would possibly explain, the bulk of them calls for a more careful analysis of the model foundations, particularly the amount and role of dark substances. From the theoretical side it is known that the role of hydrodynamics can be more important that often assumed. Moreover recently there has been a considerable theoretical effort to develop a coherent picture in General Relativity which appropriately takes into account matter inhomogeneities. By connecting and discussing different approaches and results, this workshop, aims to advance our comprehension of the large scale universe. Progress can be hoped for by combining insights from various groups of researchers studying different observational and theoretical problems. The workshop offers a unique opportunity to discuss conceptual and methodological problems of the present cosmological paradigm. Central questions are posed from observational and theoretical perspectives: - Galaxy Structures on large scales: How large are galaxy fluctuations on 100 Mpc/h scale? Do we see the predicted anti-correlations in the two-point correlation function? - Is there a systematic problem in the CMB large angle correlations? Is there true evidence for a galaxy-CMB cross correlation? - Are large scale flows at odds with LCDM predictions? - What is the role of joint effects of gravity and hydrodynamics in the theory of structure formation? - What is the role of large density inhomogeneities in General Relativity? Which effects can be observed? We of course cannot expect to obtain answers to any of those questions during this workshop but we can discover how expertise from different fields can be combined to fruitfully address them. The diversity in the background of the participants guarantees that new questions will arise and new approaches will be formulated. The central role of the workshop will be to stimulate and coordinate this interaction. http://www.lc.leidenuniv.nl/lc/web/2010/412/info.php3?wsid=412 -----------------------------------------------------------------------

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2 cosmo meetings lato 2010
by Boud Roukema 02 Mar '10

02 Mar '10

witam cosmo-pl Here are two northern summer 2010 cosmo meetings in Paris. The second one is Chalonge - which means you don't get to present your own work, at best you can ask questions/discuss. pozdr boud ---------- Forwarded message ---------- > Date: Mon, 1 Mar 2010 14:35:31 +0100 > Message SF2A No 412 - 01/03/10 > > Sur le web: http://www.sf2a.asso.fr/spip.php?rubrique7 > http://www.sf2a.asso.fr/spip.php?article226 > --------------------------------------------------------------------------- > 4. The 11th annual international meeting 'Fundamental Frontiers of > Physics', 6 - 9 July 2010, Paris > --------------------------------------------------------------------------- > > The Symposium develops around five themes: > - Big Bang Cosmology / Dark Energy > - Dark Matter/Astroparticles > - Particle physics and Fundamental Interactions > - From Intrication to Quantum Information and Quantum Gas > - Epistemology, History of Physics > > Parallel sessions will be organized as mini-workshops consisting > mostly of twenty minutes oral presentations. > > The deadline for submission of an abstract is the 15th of June and for > early registration to 'Fundamental Frontiers of Physics' is the 25th > of June, 2010. > > Please visit the website of the conference : http://ffp11.gie.im > for all relevant information. > > Transmis par Sarodia Vydelingum > > --------------------------------------------------------------------------- > 5. The 14th Paris Cosmology Colloquium 2010: "The Standard Model of > the universe: theory and observations", 22 - 24 July 2010, Paris > --------------------------------------------------------------------------- > > The Conference is within the astrofundamental physics spirit of the > Chalonge School, on recent observational and theoretical progress on > the CMB, Inflation, astrophysical dark matter, dark ages, dark energy, > and the theory of the early universe with predictive power. > > In summary, the aim of the meeting is to put together real > cosmological data and hard theory predictive approach connected to > them in the framework of the Standard Model of the Universe. > > Topics: Observational and theoretical progress in the CMB, > astrophysical dark matter, dark energy, dark ages . Large and small > scale structure formation. Inflation in connection with the CMB and > LSS data, slow roll and fast roll inflation, quadrupole suppression > and initial conditions, low CMB multipoles. CMB > polarization. Neutrinos in cosmology. > > The Meeting is open to all scientists interested in the subject. All > Informations about the meeting and registration to it are displayed at > this URL : http://chalonge.obspm.fr/colloque2010.html. > > Early Registration is strongly encouraged. > > The format of the Meeting is intended to allow easy and fruitful > mutual contact and communication. > > Sessions last for three full days in the beautiful parisian campus of > Observatoire de Paris (built on orders from Colbert and to plans by > Claude Perrault from 1667 to 1672). All sessions take place in the > historic Perrault building ("Batiment Perrault") of Observatoire de > Paris HQ, under the portraits of Laplace, Le Verrier, Lalande, Arago, > Delambre and Louis XIV. > > An exhibition will retrace the 19 years of activity of the Chalonge > School and George Smoot participation to the School along these 19 > years > > Informations on the previous Paris Cosmology Colloquia and of the > school events are available at this URL : http://chalonge.obspm.fr > (lecturers, lists of participants, lecture pdf files and photos during > the Colloquia). > > Transmis par l'Ecole Daniel Chalonge (http://chalonge.obspm.fr/)

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Moriond 2010 Cosmology (fwd)
by Boud Roukema 28 Dec '09

28 Dec '09

Moriond 2010 Cosmology Dear colleague, The next Rencontres de Moriond meeting devoted to Cosmology will be organized in La Thuile (Valle d'Aosta, Italy), March 13-20, 2008. Registration is open on http://moriond.in2p3.fr/J10/ where more details can be found (including abstract submission) The main topics covered in the conference are summarized at the end of this message looking forward to welcom you in La Thuile, with our best regards, the organizing committee ------- 1. Clusters / SZ effect Cosmology with clusters Optical detection and self calibration methods X-ray clusters Hydrodynamical simulations SZ Clusters Radio galaxies clusters 2. CMB / Polarization WMAP Planck Polarization measurements 3. Reionization / Radio Numerical simulations LOFAR: foregrounds GMRT Other projects (MWA ...) 4. Dark Energy / Dark Matter SNLS BAO / SDSS Weak lensing Cluster Mass Profile 5. Dark Matter: accelerator searches Direct search at the LHC Direct search with underground detectors Indirect seraches (Fermi / Gamma-ray astronomy) 6. Theory Modified gravity Dark energy models Primordial universe / Inflation 7. Herschel Herschel Science Demonstration Phase Initial Results --

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Grasscosmofun'09, Szczecin (Poland), 14-19.09.2009
by mpdabfz＠wmf.univ.szczecin.pl 01 Jun '09

01 Jun '09

Dear Collegue, This is the second announcement for the GRASSMANNIAN CONFERENCE IN FUNDAMENTAL COSMOLOGY (Grasscosmofun'09), Szczecin (Poland), 14-19.09.2009 which is to celebrate a bicentennial of birth of Hermann Guenter Grassmann who used to live in Szczecin in the 19th century. Details: http://cosmo.fiz.univ.szczecin.pl The early registration deadline is the 15th of June. Late registration is 31st of July. We encourage you to register and to submit abstracts for selection to oral presentations. Schedule: morning - plenary sessions; afternoon - 2 parallell sesions Preliminary programme see: http://cosmo.fiz.univ.szczecin.pl/?q=node/77 Conference publication will be in a special volume of the "Annalen der Physik" (Berlin). Invited speakers include: John D. Barrow, Univ. Cambridge, UK Martin Bojowald, Univ. Penn State, USA Robert R. Caldwell, Dartmouth College, Hanover, USA (to be confirmed) Michael Heller, Copernicus C. for Interdisciplinary Studies, Krakow, Poland Nemanja Kaloper, Univ. of California at Davis Claus Kiefer, Univ. Cologne, Germany Marek Kowalski, Humboldt University, Berlin, Germany Anthony Lasenby, Cavendish Laboratory, Cambridge, UK Renate Loll, Univ. Utrecht, The Netherlands Hermann Nicolai, Albert Einstein Institute, Golm, Germany David Polarski, Univ. Montpellier, France Alexei Starobinsky, Landau Institute, Moscow, Russia Alexander Zheltukhin, Kharkov Institute of Physics and technology Contact: gcosmo09(a)wmf.univ.szczecin.pl tel. +48 91 444 12 48 fax: +48 91 444 12 26 We are looking forward to seeing you in Szczecin! With best regards from the OC, Mariusz P. Dabrowski (chairman)

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Grassmanian Conference in Fundamental Cosmology
by mpdabfz＠wmf.univ.szczecin.pl 03 Feb '09

03 Feb '09

Szanowni Panstwo, W imieniu Komitetu Organizacyjnego zapraszam do udzialu w konferencji "Grassmannian Conference in Fundamental Cosmology", ktora odbedzie sie w dniach 14-19 wrzesnia 2009 roku w Szczecinie. Pelna informacja na temat konferencji znajduje sie na stronie Szczecinskiej Grupy Kosmologicznej: http://cosmo.fiz.univ.szczecin.pl Na tej stronie otwarta jest tez rejestracja uczestnikow. Szczegolowe zapytania mozna kierowac na adres Komitetu Organizacyjnego: gcosmo09(a)wmf.univ.szczecin.pl Z powazaniem, Mariusz P. Dabrowski Tematyka konferencji: - Supersymmetry and superstrings. - String and M-theory cosmology. - Brane cosmology. - Inflation and large-scale structure. - Extra dimensions. - Supernovae. - Cosmic Microwave Background. - Early Universe. - Phantom cosmology and exotic singularities. - Dark energy. - Quantum gravity and cosmology. - Loop quantum gravity and cosmology. - Non-standard gravities and cosmology. - Dualities. - Nonperturbative structures Zaproszeni wykladowcy: John D. Barrow Univ. Cambridge, UK Martin Bojowald Univ. Penn State, USA Robert R. Caldwell Dartmouth College, Hanover, USA (to be confirmed) Ruth Dürrer Univ. Geneve, Switzerland Michael Heller Vatican Observatory & Copernicus C. for Interdisciplinary Studies, Kraków, Poland Nemanja Kaloper Univ. California at Davis, USA Claus Kiefer Univ. Cologne, Germany Marek Kowalski Humboldt University, Berlin, Germany Anthony Lasenby Cavendish Laboratory, Cambridge, UK Renate Loll Univ. Utrecht, The Netherlands Hermann Nicolai Albert Einstein Institute, Golm, Germany David Polarski Univ. Montpellier, France Alexei Starobinsky Landau Institute, Moscow, Russia David Wands Univ. Portsmouth, UK

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galaxy formation etc. WORKSHOP NOVICOSMO 2008, SISSA, Trieste, 20-22 October 2008
by Boud Roukema 05 May '08

05 May '08

witam cosmo-pl, A "late summer" extragalactic/cosmo meeting: galaxy formation etc. WORKSHOP NOVICOSMO 2008, SISSA, Trieste, 20-22 October 2008 http://www.novicosmo.org/ pozdr boud

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sf2a : vos dernieres nouvelles (fwd)
by Boud Roukema 16 Apr '08

16 Apr '08

hi cosmo-pl, A few interesting (last minute!) conference annoncements, and one (ASTRONET) which is for people willing to invest time in astropolitics (grants, long term big ground or space telescope projects). pozdr boud > ---------- Forwarded message ---------- > Date: Tue, 8 Apr 2008 18:25:10 +0200 > ... SF2A cesr fr > > Message SF2A No 337 - 8/04/08 > Sur le web: http://www.sf2a.asso.fr/spip.php?article108 > --------------------------------------------------------------------------- > 5. Rencontres de Blois: Challenges in Astroparticle Physics (18-23 mai) > --------------------------------------------------------------------------- > > Sujet: Colloque international sur les derniers resultats et projets > dans le domaine d'Astroparticules. > > Le colloque sera un melange de papiers invites, et de contributions, > sur tout aspect, theorique et experimental, des astroparticules, de > l'astronomie gamma et de l'astronomie neutrino. > > Les contributions de jeunes chercheurs sont particulierement bienvenues. > > Transmis par Ludwik Celnikier international conference on the latest results and projects in astroparticles - a mix of invited papers, contributions on theoretical and experimental aspsects of astroparticles, gamma astronomy and neutrino astronomy http://blois.in2p3.fr/2008/ - deadline yesterday! > --------------------------------------------------------------------------- > 6. Dark Energy and Dark Matter: Observations, Experiments and Theories > --------------------------------------------------------------------------- > > The Centre de Recherche Astrophysique de Lyon (CRAL) and Institut de > Physique Nucleaire de Lyon (IPNL) are making the second announcement > for the second international conference in the CRAL/IPNL Conference > Series: "Dark Energy and Dark Matter: Observations, Experiments and > Theories" to be held July 7-11, 2008 in the city of Lyon, France. > > Registration and abstract submission is open and the deadline has been > extended to April 25, 2008. The full scientific rational and many > more information are available on: http://cralconf.univ-lyon1.fr/2008 > > Transmis par Antoine Bouchard > --------------------------------------------------------------------------- > 8. The Early Phase of Star Formation (date limite 1er mai) > --------------------------------------------------------------------------- > > Second announcement of the conference EPoS 2008: The Early Phase of > Star Formation 2008 - The Future of the Field > > The Early Phase of Star Formation 2008 - The Future of the Field > July 28 - August 1, 2008 > Max-Planck Society Conference Center Ringberg Castle, Germany > Registration Deadline: ***** 1st of May, 2008 ***** > Organized by J. Steinacker & A. Bacmann > > The conference focuses on early low- and high-mass star formation. > > The topics covered are:triggered star formation, clustered star > formation, cores, chemistry, collapse, fragmentation, jets, > competitive accretion, giant molecular clouds, binarity, magnetic > fields, initial mass function, turbulence, and early phases of disks. > > EPoS 2008 aims to explore the future of the field. Special attention > will be paid to the observational and theoretical perspectives > promising substantial progress in the field. More information & > registration: http://www.mpia.de/homes/stein/EPoS2008/ > > Transmis par Aurore Bacmann > --------------------------------------------------------------------------- > 7. ASTRONET Symposium - Second Announcement > --------------------------------------------------------------------------- > > Registration is now open for the ASTRONET Infrastructure Roadmap > Symposium to be held in Liverpool, U.K. on the dates of 16-19 June > 2008. > > Further information can be obtained at: http://www.astro.livjm.ac.uk/~airs2008/ > > IMPORTANT DEADLINES > * Application for financial support: 30 April 2008 > * Abstract Submission: 23 May 2008 > * Registration: 29 May 2008 > > REGISTRATION > > Registration for the symposium can be made online through the > following website: http://www.ljmu.ac.uk/conferences/93776.asp > Registration is free of charge and covers the cost of the venue, > coffee breaks and lunches, and the conference dinner and other social > events. Please note that the number of participants will be capped at > 400. Register early to avoid disappointment. > > FINANCIAL SUPPORT > > Limited funds will be available for supporting participants from less > privileged European countries and/or at the early stages of their > careers. More details on eligibility and how to apply are available > at: http://www.astro.livjm.ac.uk/~airs2008/Support.html. > > ABSTRACTS > > This meeting will focus specifically on the first draft of the > ASTRONET Infrastructure Roadmap, which will be made publicly available > by the beginning of May 2008. We now invite short contributions on > facilities and infrastructures within the following themes related to > the Infrastructure Roadmap: > > * High energy astrophysics, astroparticle physics and gravitational waves > * UVOIR and radio/mm facilities > * Solar telescopes, solar system missions, laboratory studies > * Theory, computing facilities and networks, Virtual Observatory > * Education, recruitment and training, public outreach, industrial links > > The principal aim of this call is to obtain feedback on the ASTRONET > Infrastructure Roadmap prior to its final publication in the Autumn of > 2008. In order to submit an abstract you must register in the first > instance. You will then receive an email with further instructions. > > ACCOMMODATION > > Please book your accommodation as soon as possible after you have > registered. We are aware of at least one other large conference is > being held in the exact same venue and period of time. Thus, demand > for accommodation in the immediate vicinity of the Arena and > Convention Centre (ACC) Liverpool will almost certainly be very > high. Leaving your booking until late may result in a longer journey > to the ACC Liverpool each day. > > Transmis par Jean-Marie Hameury

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http://arxiv.org/abs/0708.0530
by Bogusław Broda 08 Feb '08

08 Feb '08

Compilation of various pieces of original remarks and answers ============================================== REMARK: ... the cosmological constant with its usual Planck scale value is present in Eq. 11 of the manuscript. Then, in going on to Eq. 24, a subtraction is introduced (the square root of the metric determinant is replaced by the square root minus one). This constitutes the usual ad hoc subtraction of the bare cosmological constant. ANSWER: ... at first sight, the subtraction could seem ad hoc, but it is not quite so. (i) Standard argument: it follows from generally accepted rules of quantum field theory, e.g. in the path-integral formalism it corresponds to a normalization of measure; (ii) Our argument: the "one" (constant) corresponds to a contribution without any external lines, i.e. it does not influence external fields by construction, and therefore it should be excluded. REMARK: Following Eq. 24, the expression is expanded about the present time, and a residual is obtained which vanishes today but which has a similar time-dependence as that of dark energy. Hence, a connection with dark energy is postulated. However, the expansion about a fixed time does not make sense. There is nothing special about the present time which allows a subtraction to be linked with the present time. ANSWER: In principle, we could expand about any fixed time. It is only a technical assumption. But to obtain present experimental values (e.g. density) we should use present experimental data (e.g. the present Hubble constant). REMARK: The purpose of this paper is to derive the contribution to the vacuum energy of the universe from the single loop of a free quantum matter field, in order to achieve better understanding of the cosmological constant problems. Needless to say that this calculation has been approached previously in many different ways. Authors adopt a very simple approach and postulate that the mentioned quantum loop should be cut-off at the Planck scale. Then, using the Schwinger-DeWitt expansion and taking only the massless scalar field case they notice that only the a0 coefficient gives contribution to the proper cosmological constant. Furthermore, they notice that making the expansion of the metric around the flat background, the first order term can be eliminated by the coordinate transformation and therefore end up with the second order term which is a product of the squares of the Hubble parameter H and the cut-off parameter, that is the Planck mass. As a result they arrive at the induced cosmological constant which has a ”correct” order of magnitude. ANSWER: Ideologically, our work consists of two parts. The first part presents the very idea, whereas the second part presents a realization of that idea. We do not insist that the realization proposed is the best and final one. REMARK: Despite the above scheme looks appealing, it has obvious weak points. For instance, if authors incorporate the field with the mass M, the next Schwinger-DeWitt term a_1 will produce contribution which will be a product of the squares of the mass M and the Planck mass. Indeed, even for neutrino this contribution will be 60 orders of magnitude greater than the ”correct” value. The origin of this occurences is that the scheme suggested by the authors is not correct from the quantum field theory viewpoint. In fact, after the effective action is calculated, one can not perform the expansion around the flat background, because the cosmological constant term should be covariant, exactly as other terms in the effective action of gravity. The explanation of the coordinate dependence of the linear in H term is that the effective action of gravity is covariant and therefore can not include terms which are odd in metric derivatives. The discussion of this point has been given recently in gr-qc/0801.0216, where one can also find many other references on the subject. ANSWER: A massive field with the mass M poses a problem. We can propose the following two independent solutions of that problem: a “theoretical” and a “technical” one. The “theoretical” solution would assume, rather a widely accepted idea, that the mass of a particle is not a fundamental entity but rather a derived one. In principle, all masses in the standard model are generated via the Higgs mechanism. According to this point of view we could legitimately assume that all masses should be neglected at this stage. The “technical” solution instead would order us to treat the M^2 part of the a_1 coefficient analogously to the a_0 coefficient. In fact, functional dependence on metric field, and only metric dependence matters, in the both terms is identical. The only difference resides in coefficients and consists in different powers of M and s (UV cutoff), i.e. we have M^0 s^-2 and M^2 s^-1, respectively. Therefore, actually the contribution of M^2 part of a_1 would be even less than that of a_0. REMARK: ... the cosmological constant problem is much deeper than the conflict between the calculation based on the Planck cut-off and the observable value. At the first place this problem involves the fine-tuning between the induced and vacuum components of the cosmological constant, as it is explained, e.g., in [2]. ANSWER: Firstly, the huge value of the vacuum energy density is a very annoying feature in itself, and, it seems, it is desirable to explain it somehow, independently of the further issue of the cosmological constant. Secondly, there is an old and a bit controversial idea of induced gravity. Intriguingly, it appears that it also yields a correct order of magnitude of the coefficient in front of the Hilbert–Einstein gravitational action. But one of the arguments against that idea says that the huge value of the cosmological constant invalidates the very idea, at least in its Sakharov’s version (demand one-loop dominance in Visser’s classification [7]), i.e. when there are only induced terms, without bare ones. Now, the tamed cosmological term and the Hilbert–Einstein gravitational action with the purely induced coefficient (only) of a correct order of magnitude, both would fit the Sakharov’s version of induced gravity idea consistently.

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