Wednesday Colloquium



07.12.2011

"Strong gravitational lenses as standard rulers in cosmology"

Marek Biesiada (Department of Physics, Silesian University, Katowice)

The accelerating expansion of the Universe is a great challenge for both physics and cosmology. Its discovery was possible because of the advances in the extragalactic distance measurements. While standard candles most notably Type Ia supernovae kicked off the issue, it is clear that statistical standard rulers like the Baryon Acoustic Oscillations are playing an increasingly important role. I will show that strongly gravitationally lensed systems with known central velocity dispersion of the lens, are good candidates for a new class of individual standard rulers - Einstein radius being standardized by stellar kinematics. This approach, pursued recently by us, is becoming attractive in light of ongoing lens surveys like SLACS based on different protocols than older searches.


14.12.2011

"Measurements of neutrino velocity - past, present and future"

Katarzyna Grzelak (Institute of Experimental Physics, Warsaw University)

The OPERA experiment has recently presented the result on the measurement of neutrino velocity. Neutrinos from CERN were measured to arrive at the Gran Sasso Laboratory about 60ns earlier than expected assuming they travel with the speed of light. The details of the OPERA analysis and the recent updates will be presented together with the description of previous measurements of neutrino velocity and plans for the verification of the OPERA result.


21.12.2011

"What was the last Nobel Prize in Physics given for?"

Stanisław Bajtlik (NCAC, Warsaw)