
Calendar of Physics Talks Vienna
Fermion Pairing and the Effective Scalar Boson of the 2D Conformal Anomaly 
Speaker:  Daniel Blaschke (Los Alamos National Laboratory, Theory Division) 
Abstract:  Quantum fields in a curved background space lead to an anomalous trace of the total energy momentum tensor which can become macroscopic near black hole horizons. In two dimensions, the resulting effective action is the nonlocal Polyakov action. This effective action can be written in a local form by introducing one effective scalar field whose properties may hold the key to a better understanding of quantum effects in the near horizon region. In the present work, we found a curious relationship between tree graphs of stressenergy tensors of this new scalar field, and oneloop graphs of stressenergy tensors in terms of the original quantum fields. In particular, when starting from fermions the new scalar may be interpreted as an "interpolating" field describing intermediate twofermion states. Finally, we compare our results to the chiral anomaly situation known from the Schwinger … 
Date:  Mon, 21.07.2014 
Time:  10:00 
Location:  Institute for Theoretical Physics – Vienna University of Technology, Seminar room 136, Wiedner Hauptstraße 8 – 10, 10th floor, B (yellow tower) 
Contact:  Em.Univ.Prof. DI Dr. Manfred Schweda 
Gauged Linear Sigma Models, disk partition function and nonabelian matrix factorizations 
Speaker:  Mauricio Romo (Kavli IPMU) 
Abstract:  I will explain how the supersymmetric disk partition function Z_{D^2}
of gauged linear sigma models relate to the central charge of objects
in the category of Bbranes of a CalabiYau (CY). The advantage of
this approach is that Z_{D^2} provides an expression at every point
in the quantum corrected moduli space of the CY. The Bbranes in
these models are realized naturally as matrix factorizations,
equivariant under the gauge group. I will explain how to relate them
to more familiar objects such as coherent sheaves on the CY and show
applications of this result to different type of CYs, including more
exotic noncomplete intersections.

Date:  Mon, 21.07.2014 
Time:  14:00 
Duration:  60 min 
Location:  Institute for Theoretical Physics – Vienna University of Technology, Seminar room 136, Wiedner Hauptstraße 8 – 10, 10th floor, B (yellow tower) 
Contact:  Johanna Knapp 
