Jyväskylä Cosmology Group
Seminars and Visitors Schedule
We regularly host international researchers visiting our cosmology group. Our canonical slot for cosmology seminars is Tuesdays at 13:00. We also have regular weekly meetings to discuss the latest results on our field.
NEXT SCHEDULED TALKS
Jan 22 (Tue), 13:00 in FL244 Abhishek Atreya CAPSS, Bose Institute
In this talk we focus on the self interacting dark matter (SIDM) paradigm which can provide us with a consistent explanation of certain astrophyiscal observations that are in conflict with the cold dark matter (CDM) paradigm. We will make use of the constraints on SIDM cross-sections from astrophysical observations, to estimate the mean free path of the dark matter particles. Assuming thermalization within this volume we estimate the shear viscosity (η) and bulk viscosity (ζ) of SIDM, within kinetic theory formalism. The dissipation due to viscosity affects the solution of Einstein's equation through energy conservation. In a simplified model, we calculate this change and try to argue that σ/m constraints on SIDM provide us with sufficient viscosity to contribute significantly to the observed cosmic acceleration at present epoch. We next calculate H(z) and q(z) within the simplified model, and perform χ2 analysis, using the the cosmic chronometer data, to estimate the best fit model parameters . The best fit values also explain type IA supernova data quite well.
RECENT VISITORS
2018
Aug 27 - Aug 31: Kalle Ala-Mattinen (University of Helsinki)
Aug 27 - Aug 31: Kimmo Tuominen (University of Helsinki)
Jun 18 - Jun 19: Gianmassimo Tasinato (University of Swansea)
Jun 7 - Jun 8: Daniel Cutting (University of Sussex)
May 7 - May 17: Thomas Garratt (University of Würzburg)
May 7 - May 11: Werner Porod (University of Würzburg)
Apr 16 - Apr 18: Tommi Markkanen (Imperial College)
Mar 13: David Weir (Helsinki University / HIP)
Jan 15 - Jan 19: Thomas Garratt (University of Würzburg)
2017
Nov 16 - Nov 21: James Cline (McGill University)
Nov 16: Giuseppe Fanizza (University of Zurich)
Oct 18 - Oct 27: Tomo Takahashi (Saga University, Japan)
Oct 1 - Oct 5: Kazunori Kohri (KEK, Japan / The University of Oxford)
Jun 13 - Jun 16: Tomislav Prokopec (Utrecht University)
May 23 - May 26: Tommi Markkanen (King's College, London)
May 22: Stefano Camera (INFN, Torino)
Apr 24 - Apr 25: Christian Byrnes (University of Sussex)
Apr 6 - Apr 7: Francesco Montanari (Helsinki Institute of Physics)
Feb 1 - Feb 2: Venus Keus (Helsinki University)
Jan 24 - Jan 31: Tomo Takahashi (Saga University, Japan)
2016
Dec 8 - Dec 9: Aurora Meroni (Nordita/HIP)
Nov 28 - Dec 2: Stephen Stopyra (Imperial College, London)
Oct 24 - Oct 28: Thomas Garratt (University of Würzburg)
Oct 17 - Oct 21: James Cline (McGill University)
Sep 18 - Sep 24: Alexey Golovnev (St. Petersburg State University)
Sep 18 - Sep 24: Tomi Koivisto (Nordita)
Sep 1: David Weir (Stavanger University)
May 25 - May 27: Martin Krssak (Sao Paulo State University)
May 23 - May 27: Tomi Koivisto (Nordita, Stockholm)
May 12 - May 13: Mark Hindmarsh (University of Sussex/University of Helsinki)
May 10 - May 13: Tomo Takahashi (Saga University, Japan)
May 2 - May 4: Tommi Markkanen (Kings College, London)
Apr 12 - Apr 15: Tommi Tenkanen (University of Helsinki)
Mar 17 - Mar 18: Thomas Jacques (SISSA)
Mar 3 - Mar 8: Jonathan White (KEK, Japan)
2015
Dec 2 - Dec 5: James Cline (McGill University)
Nov 15: Mikko Laine (University of Bern)