CPT

Calendar of Physics Talks Vienna

Integrable aspects of the AdS/CFT duality
Speaker:Zoltan Bajnok (Wigner Research Centre, Budapest)
Abstract:I will review the integrable aspects of the duality which relates IIB superstrings on AdS5xS5 to the maximally supersymmetric 4D gauge theory. As the gauge theory is conformal it can be completely characterized by its two and three point functions. The two-point functions are determined by the scaling dimensions, which correspond to the energies of string states. These scaling dimensions also fix the space-time dependence of the three-point functions upto a coupling constant dependent quantity called the three-point coupling, which is related to the annihilation and creation of string states (the string vertex). I will explain, how integrability of the AdS/CFT correspondence can be used to calculate the scaling dimensions and the three-point couplings.
Date: Tue, 25.09.2018
Time: 13:45
Duration: 60 min
Location:Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:S. Fredenhagen

AdS and Cold Atoms
Speaker:Oleg Evnin (Bangkok/Brussels)
Abstract:Taking nonrelativistic limits of field systems in Anti-de Sitter (AdS) spacetime results in variants of the Gross-Pitaevskii equation describing cold atomic gases in harmonic traps (which can be implemented in contemporary terrestrial experiments). This relation underlies the similarities in weakly nonlinear dynamics of these two classes of systems (AdS and atomic gases) whose investigation is normally motivated by rather different physical goals (phenomenology of Bose-Einstein condensation vs. studies of strongly coupled conformal field theories in the context of AdS holography). I will explain how the weakly nonlinear dynamics of such systems is analyzed via the so-called resonant approximation, and present a range of surprising exact results and open questions for the effective nonlinear resonant systems arising from such analysis.
Date: Tue, 25.09.2018
Time: 15:30
Duration: 60 min
Location:Arbeitsgruppe Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock, 1090 Wien
Contact:P.T. Chrusciel, M. Maliborski

Quantum resonant systems, integrable and chaotic
Speaker:Oleg Evnin (Bangkok/Brussels)
Abstract:Resonant systems emerge as weakly nonlinear approximations to problems with highly resonant linearized perturbations. Examples include nonlinear Schrödinger equations in harmonic potentials and nonlinear dynamics in Anti-de Sitter spacetime. The classical dynamics within this class of systems can be very rich, ranging from fully integrable to chaotic as one changes the values of the mode coupling coefficients. I'll report on investigations of quantum infinite-dimensional resonant systems, which are mathematically a highly special case of two-body interaction Hamiltonians (extensively studied in condensed matter, nuclear and high-energy physics). Despite the complexity of the corresponding classical dynamics, the quantum version turns out to be emarkably simple, with the Hamiltonian being block-diagonal in the Fock basis, with all blocks of varying finite sizes. Being solvable in . . .
Date: Wed, 26.09.2018
Time: 14:00
Duration: 90 min
Location:Arbeitsgruppe Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock, 1090 Wien
Contact:P.T. Chrusciel, M. Maliborski

Canonical Energy and Hertz Potentials for Perturbations of Schwarzschild Spacetime
Speaker:Bob Wald (Chicago)
Abstract:I will describe recent results with K. Prabhu that show positivity of the canonical energy of perturbations of Schwarzschild that are obtained from a Hertz potential. We will also show how the energy quantity arising in the Schwarzschild stability proof of Dafermos, Holzegel, and Rodnianski is related to Hertz potentials and canonical energy. Much of the talk will be spent reviewing canonical energy and Hertz potentials.
Date: Thu, 27.09.2018
Time: 15:00
Duration: 60 min
Location:Arbeitsgruppe Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock, 1090 Wien
Contact:P.T. Chrusciel