Cosmo-torun

cosmo-torun@cosmo.torun.pl

328 discussions

CDMS II: 2 events, P=23%, Fig 3 looks good and Fig 5 agrees with DAMA/LIBRA
by Boud Roukema 18 Dec '09

18 Dec '09

hi cosmo-torun, http://cdms.berkeley.edu/ http://cdms.berkeley.edu/results_summary.pdf http://cdms.berkeley.edu/0912.03592v2.pdf CDMS II: 2 events, P=23%, Fig 3 looks good and Fig 5 agrees with DAMA/LIBRA. There was big blog rumour about this - the significance is still low, but the results look cool to me. :) LDM and DAMA/LIBRA/CDMS particles will probably have to co-exist. There's a bit of discussion here: http://cosmocoffee.info/viewtopic.php?t=1487 And here's an article that totally ignores DAMA/LIBRA, presumably because DAMA/LIBRA is an Italian, not USA, experiment: http://www.sciencenews.org/view/generic/id/50960/title/Experiment_detects_p… pozdr boud

1 0

cfalib: we should get Krasinski - Inhomogeneous Cosmological Models
by Boud Roukema 07 Dec '09

07 Dec '09

Hi Karolina, Could we please put: Inhomogeneous Cosmological Models Andrzej Krasinski Cambridge University Press 1997 ISBN 978-0521481809 on our list of priority books whenever there's some budget money that needs to be spent? (Sometimes at the end of the year there is money that will be lost if it doesn't get spent.) It seems we don't have this book anywhere in the UMK library system. The Universe is certainly inhomogeneous - UMK would not exist if the Universe were perfectly homogeneous (since LSS and galaxies and planets would not exist). The question is not *if* the Universe is inhomogeneous, the question is *how important* the inhomogeneity is, i.e. to what degree assuming a perfectly homogeneous model and then adding perturbations is a good enough approximation to reality. pozdr boud

2 1

textbook by Paddy: "Gravitation" (CUP)
by Boud Roukema 13 Nov '09

13 Nov '09

hi Cfalib, cosmo-torun, i think that Cfalib should order Paddy's new book on gravitation for our library, depending on when there's money available. Often at the end of the year there's budget money that needs to be spent, and the book doesn't seem very expensive anyway (though "c." probably means "circa" = $\sim$, which maybe means they'll increase the price if the book gets good reviews or if people pre-order it?). See the summary at GRTOC.pdf - link below. Any thoughts? pozdr boud > Gravitation: Foundations and Frontiers > T. Padmanabhan > > [To be published by Cambridge University Press, January 2010.] > > The book can be ordered from this site: > http://www.cambridge.org/uk/catalogue/catalogue.asp?isbn=9780521882231 > > DESCRIPTION: > > This is a comprehensive advanced level textbook on Gravitation. The front > matter (table of contents etc.) is available as a pdf file here: > > http://www.iucaa.ernet.in/~paddy/books/GRTOC.pdf > > Covering all aspects of gravitation in a contemporary style, this advanced > textbook is ideal for graduate students and researchers in all areas of > theoretical physics. The 'Foundation' section develops the formalism in six > chapters, and uses it in the next four chapters to discuss four key > applications - spherical spacetimes, black holes, gravitational waves and > cosmology. The six chapters in the 'Frontier' section describe cosmological > perturbation theory, quantum fields in curved spacetime, and the Hamiltonian > structure of general relativity, among several other advanced topics, some of > which are covered in-depth for the first time in a textbook. The modular > structure of the book allows different sections to be combined to suit a > variety of courses. Over 200 exercises are included to test and develop the > reader's understanding. There are also over 30 projects, which help readers > make the transition from the book to their own original research. > > HIGHLIGHTS: > > * Develops the formalism and uses it to discuss four key applications - > spherical spacetimes, black holes, gravitational waves and cosmology. > > * Describes several advanced topics, some of which are covered in-depth for the > first time in a textbook. > > * Different sections can be easily combined to meet the needs of a variety of > courses.

2 1

workshop next week Fri 20.11.2009
by Boud Roukema 12 Nov '09

12 Nov '09

hi all, i forgot to announce a research workshop yesterday (2 days before Friday), so IMHO the best is to wait till Fri next week. i'll do my best to announce something by Wednesday... Any volunteers? Please volunteer directly on the list :) or at least tell me by another method. pozdr boud

1 0

PROPOSAL: cosmo coffee workshop Fri 13:00 26.09.2009 - conference inspirations
by Boud Roukema 29 Oct '09

29 Oct '09

hi everyone, i propose one cosmo coffee research-level workshop before the semester starts: 13:00 Fri 26.09.2009 @KRA Unless there are other volunteers, i propose that we have a loose discussion based on what people find interesting from these online conference notes: http://cosmo.torun.pl/Cosmo/InvisibleUniverse2009 (done) http://cosmo.torun.pl/Cosmo/GrassmannCosmoFun2009 (to do next week) Bartek, Agnieszka, Zbyszek - if you take laptops to GrassCosmoFun or otherwise have web access during the meeting, then feel free to add to these notes. Having multiple wiki-edits of notes on a talk while it takes place could be particularly interesting... pozdr boud

1 2

Invisible Universe meeting - random notes
by Boud Roukema 01 Jul '09

01 Jul '09

hi cosmo-torun, i'm making some notes during some of the talks at the Invisible Universe meeting. See http://cosmo.torun.pl/Cosmo/InvisibleUniverse2009 and use arXiv.org to find the related papers! pozdr boud

1 0

some notes after today's talk - LDM
by Boud Roukema 22 May '09

22 May '09

witam cosmo-torun * circular polarisation from synchrotron processes? Kennett & Melrose, 1998, PASA, 15, 211 http://www.atnf.csiro.au/pasa/15_2/kennett/paper/node3.html > In some sources it may be that the relativistic > particles are electron-positron pairs (e.g., Wilson & > Weiler 1997). Electrons and positrons contribute with > the same sign to the linearly polarized component and > with the opposite sign to the circularly polarized > component. If the distributions of electrons and > positrons are the same the wave modes can have no > circular component and, more importantly, the intrinsic > circular polarization from the synchrotron radiation > sums to zero. So if we have different distributions of electrons and positrons, then we get a circular polarisation component. i'm sure there must be more basic texts on this subject... pozdr boud

2 9

non-baryonic dark matter now detected at 8.2 sigma: DAMA/NaI + DAMA/LIBRA - Bernabei et al. ArXiv:0804.2741
by Boud Roukema 20 May '09

20 May '09

witam cosmo-torun, The DAMA detections of nbDM seem to be getting even stronger! Bernabei et al. ArXiv:0804.2741 now have their annual modulation signal of non-baryonic dark matter from the Galactic DM Halo detected "at 8.2 sigma CL": DAMA/NaI + DAMA/LIBRA. Figures 2, 4 and 8 are especially impressive. Savage et al. have a nice article ArXiv:0808.3607 showing the regions of parameter space for WIMPS for which are consistent with both the DAMA detection and all the non-detections in other experiments. E.g. spin-dependent, proton-only couplings for a particle mass of about 5-9 GeV are one region compatible with all the data. This doesn't stop LDM (light dark matter) *also* being a correct hypothesis for nbDM - multiple DM particles may contribute together to non-baryonic DM. pozdr boud

1 1

cosmo talk = ? Fri 10 april && DE as a continuity condition Fri 17 April
by Boud Roukema 17 Apr '09

17 Apr '09

hi cosmo-torun, i haven't seen an announcement for a talk tomorrow (Fri 10 April), will there be one? Anyway, i propose for 16.00 Fri 17 April: Dark Energy as a spatial continuity condition (arXiv:0904.0975) Moze byc? pozdr boud

2 2

dark energy from continuity, finiteness and homogeneity (nothing exotic)
by Boud Roukema 07 Apr '09

07 Apr '09

witam wszystkim na cosmo-torun, If space is flat and compact, then dark energy does not require any exotic explanation, it's just a stretching effect required by the assumptions of homogeneity and continuity. http://arxiv.org/abs/0904.0975 Geometry rather than exotic particle physics or modifications of gravity. Enjoy. :) pozdr boud

1 0

← Newer
1
...
4
5
6
7
8
9
10
...
33
Older →

Jump to page:

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

Cosmo-torun