HIP NEWS April 25th 2016
DEPARTMENT OF PHYSICS / HIP JOINT COLLOQUIA / SEMINARS
Tuesday 26 April 2016 at 10.15 in A315
Thomas Konstandin (Desy)
Effective actions in particle physics and cosmology
Abstract: Effective actions are an invaluable tool in particle physics and cosmology. For example, they are used to determine properties of the Higgs or the stability of the vacuum. Other applications include the sphaleron rate in the early universe or the characteristics of the electroweak phase transition. In this talk, I will give an extensive introduction to the topic and finally touch on some advanced questions as infrared problems or gauge-dependence.
Wednesday 27 April 2016 at 14.15 in A315
Steen Hansen (DARK, Copenhagen)
Pancakes in space
Abstract: The cosmological web consists of equilibrated galaxies and clusters of galaxies, one dimensional filaments, two dimensional sheets (also called Zeldovich pancakes) and three dimensional voids.
I will discuss the first detection of two Zeldovich pancakes near the Coma cluster. These sheets/pancakes, which are few Mpc wide and about 10 Mpc long, are very cold structures with velocity dispersion about 100 km/sec. In comparison, groups of galaxies have dispersions around 300 km/sec.
By measuring the departure from a pure Hubble flow of the galaxies belonging to the sheets/pancakes, one can determine the virial mass of the nearby galaxy cluster, and I will discuss how this method complements other methods.
Finnish for international personnel, summer 2016
The summer 2016 course programme is available at helsinki.fi/finnishcourses
S. Hansen 27.4. – 29.4. (FM)
L. Boldizsar 13.4. – 26.4. (EB)
M. Hindmarsh 29.4. – 12.6. (KR)
T. Konstandin 26.4. – 27.4. (OL)
A. Lopez 29.4. – 13.6. (MH, KR)