Topic: 
Vorstellung der Arbeitsgruppen 
Date: 
21.10.19 
Time: 
16:15 
Place: 
H6 
Guest: 
Arbeitsgruppen der Physik 
Abstract: 

Contact person: 
Topic: 
Relativistic hydrodynamics, heavyion collisions, dynamical black holes and resurgent series 
Date: 
18.10.19 
Time: 
16:15 
Place: 
V3201 
Guest: 

MaxPlanckInstitute for Gravitational Physics, Potsdam 

Abstract: 
The past 12 years has constituted the golden age for theoretical studies of relatativistic hydrodynamics. The experimental motivation for these developments came from ultrarelativistic heavyion collision at RHIC and LHC accelerators in which the paradigm of stronglyinteracting medium modelled hydrodynamically became the working horse for explaining the data. These experimental and phenomenological developments have come handinhand with theoretical progress in understanding relativistic hydrodynamics as an effective description embedded in quantum field theory. In my colloquium I will review the line of thought based on AdS/CFT (holography), an approach to study stronglycoupled quantum field theories using gravitational techniques, focusing on understanding the limits of applicability of relativistic hydrodynamics in farfromequilibrium quantum field theory. A beautiful spinoff of this analysis is understanding hydrodynamic gradient expansion as a part of a transseries, which encodes, through resurgence, information about genuinely nonequilibrium excitations of a collective state of matter. Based on a series of works reviewed in arXiv:1610.02023 and arXiv:1707.02282, as well as some later / ongoing work. 
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Topic: 
Quark Mass Definition and Extraction from (2+1+1)Flavor Lattice QCD 
Date: 
24.10.19 
Time: 
14:15 
Place: 
D6135 
Guest: 

American Physical Society 

Abstract: 
I summarize a new heavy quark mass definition, the minimal renormalon subtracted (MRS) mass by the TUM QCD collaboration. It is based on the relation between the heavy quark mass and heavylight meson masses in heavy quark effective theory. The Fermilab Lattice, MILC, and TUM QCD collaborations then used this new method to extract heavy quark masses using (2+1+1)flavor HISQ ensembles of the MILC collaboration including ensembles with physical light quarks. I end with showing results on heavylight pseudoscalar meson decay constants obtained in a similar analysis. 
Contact person: 
Topic: 
tba 
Date: 
31.10.19 
Time: 
14:15 
Place: 
D5153 
Guest: 
Christian Eidecker 
Bielefeld University 

Abstract: 

Contact person: 
Topic: 
Critical behaviour and characteristic polynomials of nonHermitian random matrices 
Date: 
23.05.19 
Time: 
16:15 
Place: 
D5153 
Guest: 

University of Sussex 

Abstract: 
I will discuss some recent developments regarding the normal matrix model. In particular my interest will be in certain critical models where the limiting support of the eigenvalues can radically change its topology by slightly adjusting an external parameter. I will discuss how aspects of the model can be explicitly mapped to the study of expectations of characteristic polynomials of nonHermitian random matrices (e.g. Ginibre or truncated unitary). Many of these averages are related to Painlevé transcendents, and by exploiting this, a precise and nontrivial asymptotic expansion of partition functions can be calculated in the critical models. This is joint work with Alfredo Deaño (University of Kent). 
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Topic: 
Spectral radius of random matrices with independent entries 
Date: 
23.10.19 
Time: 
16:15 
Place: 
V3201 
Guest: 
Johannes Alt 
University of Geneva 

Abstract: 
We consider random n x n matrices X with independent and centered entries and a general variance profile. We show that the spectral radius of X converges with very high probability to the square root of the spectral radius of the variance matrix of X when n tends to infinity. We also establish the optimal rate of convergence, that is a new result even for general i.i.d. matrices beyond the explicitly solvable Gaussian cases. The main ingredient is the proof of the local inhomogeneous circular law [arXiv:1612.07776] at the spectral edge. This is joint work with L\'{a}szl'{o} Erd\'"os and Torben Kr\"uger. 
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