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Calendar of Physics Talks Vienna
| The holographic (quark-)gluon-plasma |
| Speaker: | Karl Landsteiner (Autonoma Univ. Madrid) |
| Date: | Tue, 14.08.2007 |
| Time: | 14:00 |
| Location: | Institut f�r Theoretische Physik, TU Wien, Seminarraum 136, Wiedner Hauptstr. 8-10, 10th floor |
| Contact: | rebhana at tph dot tuwien.ac.at |
| Spacetime Emergence in the Robertson-Walker Universe from a Matrix model |
| Speaker: | Rene Meyer |
| Abstract: | Using a novel, string theory-inspired formalism based on a Hamiltonian
constraint, we obtain a conformal mechanical system for the spatially flat
four-dimensional Robertson-Walker universe. Depending on parameter
choices, this system describes either a relativistic particle in the
Robertson-Walker background, or metric fluctuations of the
Robertson-Walker geometry. On that basis we derive a tree-level matrix
model in this time-dependent background by comparing with 2-brane
dynamics. Imposing the Hamiltonian constraint of the matrix model forces
the spacetime geometry to be fuzzy near the cosmological singularity,
while the classical Robertson-Walker geometry emerges as the universe
expands. From our approach we also derive the temperature of the D0 branes
described by the matrix model, and show that they interpolate between a
radiation and a matter dominated era. |
| Date: | Thu, 16.08.2007 |
| Time: | 15:00 |
| Location: | Seminar room Institute for Theoretical Physics, Vienna University of Technology |
| Contact: | Daniel Grumiller |
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