Hintergrund-oben
Home | Studies | Research | Facilities | Resources | People | 
  
change language

Upcoming Events

 

Colloquium

Topic:

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

Date:

22.05.17

Time:

16:15

Place:

H6

Guest:

Prof. Dr. Klaus Blaum

Max-Planck-Institut für Kernphysik, Heidelberg

Abstract:

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.

Contact person:

J. Schnack

Colloquium Mathematical Physics

Topic:

tba

Date:

21.04.17

Time:

16:15

Place:

V2-210/216

Guest:

Yan Fodorov

King's College London

Abstract:

Contact person:

G. Akemann

Seminar High Energy Physics

Topic:

Asymmetric Dark Matter and Baryogenesis from Pseudoscalar Inflation

Date:

09.02.17

Time:

14:15

Place:

D6-135

Guest:

Eray Sabancilar

Bielefeld

Abstract:

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.

Contact person:

D. Bödeker

Seminar Condensed Matter

Topic:

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

Date:

02.02.17

Time:

14:15

Place:

D5-153

Guest:

Alessandro Chiesa

Università degli Studi di Parma

Abstract:

Contact person:

Jürgen Schnack

Seminar Mathematical Physics

Topic:

Induced QCD

Date:

02.02.17

Time:

16:00

Place:

D5-153

Guest:

Robert Lohmeyer

University of Regensburg

Abstract:

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.

Contact person:

Gernot Akemann

Seminar AG Zufallsmatrizen

Topic:

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

Date:

25.01.17

Time:

14:15

Place:

V3-201

Guest:

Pierpaolo Vivo

King's College London

Abstract:

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.

Contact person:

Mario Kieburg



  • @ 2008 Uni Bielefeld
  • | Letzte Änderung: 23.11.2011
  •  
  • | Kontakt
  • | Impressum
  • | Druckansicht PDF