# Aktuelle Veranstaltungen

## Kolloquium

Thema:

### Measuring the World - Precision Measurements of Fundamental Properties of Atoms and Nuclei

Datum:

22.05.17

Uhrzeit:

16:15

Ort:

H6

Vortragender:

Prof. Dr. Klaus Blaum

Max-Planck-Institut für Kernphysik, Heidelberg

Inhalt:

The presentation will concentrate on recent applications with exciting results of Penning traps in atomic and nuclear physics with cooled and stored exotic ions. These are high-accuracy mass measurements of short-lived radionuclides, g-factor determinations of the bound-electron in highly-charged, hydrogen-like ions and g-factor measurements of the proton and antiproton. The experiments are dedicated to nuclear-, neutrino- and astrophysics studies in the case of mass measurements on radionuclides, and to the determination of fundamental constants and a CPT test using g-factor measurements.

Ansprechpartner:

J. Schnack

## Kolloquium Mathematische Physik

Thema:

### tba

Datum:

21.04.17

Uhrzeit:

16:15

Ort:

V2-210/216

Vortragender:

Yan Fodorov

King's College London

Inhalt:

Ansprechpartner:

G. Akemann

## Seminar Hochenergiephysik

Thema:

### Asymmetric Dark Matter and Baryogenesis from Pseudoscalar Inflation

Datum:

09.02.17

Uhrzeit:

14:15

Ort:

D6-135

Vortragender:

Eray Sabancilar

Bielefeld

Inhalt:

I will talk about how both the baryon asymmetry of the Universe and the dark matter abundance can be explained within a single framework that makes use of maximally helical hypermagnetic fields produced during pseudoscalar inflation and the chiral anomaly in the Standard Model. I will focus on a minimal asymmetric dark matter model free from anomalies and constraints. The observed baryon and the dark matter abundances are achieved for a wide range of inflationary parameters, and the dark matter mass ranges between 7-15 GeV. The novelty of this mechanism stems from the fact that the same source of CP violation occurring during inflation explains both baryonic and dark matter in the Universe with only two inflationary parameters, hence addressing all the initial condition problems in an economical way.

Ansprechpartner:

D. Bödeker

## Seminar Kondensierte Materie

Thema:

### Quantum Information Processing with spin systems: from modeling to realistic implementations

Datum:

02.02.17

Uhrzeit:

14:15

Ort:

D5-153

Vortragender:

Alessandro Chiesa

Università degli Studi di Parma

Inhalt:

Ansprechpartner:

Jürgen Schnack

## Seminar Mathematische Physik

Thema:

### Induced QCD

Datum:

02.02.17

Uhrzeit:

16:00

Ort:

D5-153

Vortragender:

Robert Lohmeyer

University of Regensburg

Inhalt:

We explore an alternative discretization of continuum SU(Nc) Yang-Mills theory on a Euclidean spacetime lattice, originally introduced by Budzcies and Zirnbauer. In this discretization the self-interactions of the gauge field are induced by a path integral over Nb auxiliary boson fields, which are coupled linearly to the gauge field. The main progress compared to earlier approaches is that Nb can be as small as Nc. In the main part of this talk we (i) extend the proof that the continuum limit of the new discretization reproduces Yang-Mills theory in two dimensions from gauge group U(Nc) to SU(Nc), (ii) derive refined bounds on Nb for non-integer values, and (iii) perform a perturbative calculation to match the bare parameter of the induced gauge theory to the standard lattice coupling. Furthermore, we will present some numerical evidence in support of the conjecture that the induced gauge theory reproduces Yang-Mills theory also in more than two dimensions.

Ansprechpartner:

Gernot Akemann

## Seminar AG Zufallsmatrizen

Thema:

### Radial statistics in the two-dimensional one-component plasma and associated phase transitions

Datum:

25.01.17

Uhrzeit:

14:15

Ort:

V3-201

Vortragender:

Pierpaolo Vivo

King's College London

Inhalt:

The two-dimensional one-component plasma is an ubiquitous model in statistical physics. For special values of the coupling constant $\beta q^2$ (where q is the particles charge and ? the inverse temperature), the model also corresponds to the eigenvalues distribution of normal matrix models. I will discuss several features of the system - in the limit of large number N of particles for generic values of the coupling constant. I show that the statistics of a certain class of radial observables produces a rich phase diagram: their asymptotic behaviour in terms of large deviation functions is calculated explicitly, including next-to-leading terms up to order 1/N. I will discuss a split-off phenomenon associated to atypical fluctuations of the edge density profile, and show explicitly that a failure of the fluid phase assumption of the plasma can break a genuine 1/N-expansion of the free energy. An outlook on the problem of spatially constrained Coulomb gas systems in any dimensions and universality of the associated third-order phase transition will also be offered.

Ansprechpartner:

Mario Kieburg

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