Conveners
Applications Beyond QCD
- Eigo Shintani
Applications Beyond QCD
- Yasufumi Araki
Arata Yamamoto
(The University of Tokyo)
17/07/2015, 14:00
Applications Beyond QCD
Talk
The complex Langevin method is one hopeful candidate to tackle the sign problem.
This method is applicable not only to QCD but also to nonrelativistic field theory.
We present the simulation results of nonrelativistic condensed matter systems.
Dr
Taro Kimura
(RIKEN)
17/07/2015, 14:20
Applications Beyond QCD
Talk
Topological insulators are a new class of materials which have gapped spectra in the bulk, but are accompanied by topologically protected gapless excitations at the surface (edge) of the system. These phenomena have a close relationship with symmetry and dimensionality of the system through quantum anomalies. We point out that such a surface state is a physical realization of the...
63.
Chiral Magnetic Conductivity in an interacting lattice model of a parity-breaking Weyl semimetal
Mr
Matthias Puhr
(Regensburg University)
17/07/2015, 14:40
Applications Beyond QCD
Talk
With the recent experimental realization of Dirac and Weyl semimetals it has become possible to study the Chiral Magnetic Effect (CME) in clean table-top experiments. We present results of a mean-field study of the static Chiral Magnetic Conductivity (sCMC) in a simple lattice model of a parity-breaking Weyl semimetal. Our model is given by the lattice Wilson-Dirac Hamiltonian with on-site...
Dr
Maksim Ulybyshev
(Regensburg University)
17/07/2015, 15:00
Applications Beyond QCD
Talk
Recent experimental results [Nature Physics, 8 (2012) 550 and Nature 505 (2014) 528] indicate that graphene turns into insulator in sufficiently strong magnetic field. However, the exact nature of this state is still elusive and there are large discrepancies between theoretical predictions and experimental results.
To resolve this discrepancies extensive simulations of graphene in external...
Mr
Denis Boyda
(Far Eastern Federal University)
17/07/2015, 15:20
Applications Beyond QCD
Talk
There was a long time disagreement in literature between theoretical calculations and experimental data about conductor-insulator phase transition in graphene. This contradiction was resolved in the papers [Phys. Rev. Lett. 111, 56801 (2013)] and [Phys. Rev. B 89, 195429 (2014)] where chiral condensate was studied taking into account screening of Coulomb potential by $\sigma$-electrons of...
Dr
Yasufumi Araki
(Institute for Materials Research, Tohoku University)
17/07/2015, 15:40
Applications Beyond QCD
Talk
We study the strong correlation effect from Coulomb interaction in two- and three-dimensional Dirac semimetals. Effective field theory for the interacting Dirac semimetals can be constructed in terms of quantum electrodynamics (QED). We propose a U(1) lattice gauge theory formulation with the internal degrees of freedom, such as spin and orbitals (pseudospin), explicitly. In the strong...
Dr
Alexei Bazavov
(University of California, Riverside/University of Iowa)
18/07/2015, 09:00
Applications Beyond QCD
Talk
We present a gauge-invariant effective action for the Abelian Higgs model in 1+1 dimensions. It is constructed by integrating out the gauge field and then using the hopping parameter expansion. The latter is tested with Monte Carlo simulations for small values of the scalar self-coupling. In the opposite limit, at infinitely large self-coupling, the Higgs mode is frozen and the partition...
Liam Keegan
(CERN)
18/07/2015, 09:20
Applications Beyond QCD
Talk
The mass anomalous dimension for several gauge theories with an infrared fixed point has recently been determined using the mode number of the Dirac operator. In order to better understand the sources of systematic error in this method, we apply it to a simpler model, the massive Schwinger model with two flavours of fermions, where analytical results are available for comparison with the lattice data.
Dr
Yuya Shimizu
(RIKEN Advanced Institute for Computational Science)
18/07/2015, 09:40
Applications Beyond QCD
Talk
We estimate the critical point of the Schwinger model in the theta vaccum by taking the continuum limit of Wilson's lattice formulation. The decorated tensor renormalization group which has been recently proposed by Dittrich et al. is employed for numerical investigation. We compare our numerical results with those of Byrnes et al., which were derived from Kogut-Susskind's lattice formulation...
Mr
Daniel Schmidt
(Theoretisch-Physikalisches Institut, Jena University)
18/07/2015, 10:00
Applications Beyond QCD
Talk
The Thirring model is a four fermion theory with vector interaction. We study it in three dimensions, where it is closely related to QED and other models used to describe properties of graphene. In addition it is a good toy model to study chiral symmetry breaking, since a phase with broken chiral symmetry is present for the model with one fermion flavour. On the other hand, there is no such...
Dr
Takuya Kanazawa
(RIKEN iTHES)
18/07/2015, 10:20
Applications Beyond QCD
Talk
The first lattice formulation of Lifshitz-type gauge theories is presented.
While the Lorentz-invariant Yang-Mills theory is not renormalizable in five dimensions, non-Abelian Lifshitz-type gauge theories are renormalizable and asymptotically free. We construct a lattice gauge action and numerically examine the continuum limit and the bulk phase structure.
Dr
Christopher Monahan
(University of Utah)
18/07/2015, 10:40
Applications Beyond QCD
Talk
The gradient flow has proved a valuable tool to the lattice community, with a range of applications to a variety of lattice calculations, from scale-setting to renormalisation. In this talk, I will focus on the gradient flow as a tool to suppress power-divergent mixing, a consequence of the hypercubic symmetry of the lattice regulator that is a particular difficulty for calculations of high...
