28 August 2016 to 4 September 2016
Europe/Athens timezone

Towards overcoming the Monte Carlo sign problem with tensor networks - the case of the two-flavour Schwinger model with chemical potential

30 Aug 2016, 16:00
30m
Alexandros II (Makedonia Palace)

Alexandros II

Makedonia Palace

Section A Focus Subsection: Emergent gauge fields and chiral fermions Section A: Focus Subsection

Speaker

Dr Krzysztof Cichy (Goethe University Frankfurt)

Description

The study of lattice gauge theories with Monte Carlo simulations is hindered by the infamous sign problem that appears under certain circumstances, in particular at non-zero chemical potential. So far, there is no universal method to overcome this problem. However, recent years brought a new class of non-perturbative Hamiltonian techniques named tensor networks, where the sign problem is absent. In previous work, we have demonstrated that this approach, in particular matrix product states in 1+1 dimensions, can be used to perform precise calculations in a lattice gauge theory, the massless and massive Schwinger model. We have computed the mass spectrum of this theory, its thermal properties and real-time dynamics. In this work, we extend our calculations to the case of two flavours and non-zero chemical potential. We are able to reliably reproduce known analytical results for this model, thus demonstrating for the first time that tensor networks can tackle the sign problem of a lattice gauge theory at finite density.

Primary author

Dr Krzysztof Cichy (Goethe University Frankfurt)

Co-authors

Dr Hana Saito (University of Tsukuba) Prof. J. Ignacio Cirac (Max Planck Institute for Quantum Optics) Dr Karl Jansen (DESY) Dr Mari Carmen Banuls (Max-Planck-Institute fo Quantum Optics) Mr Stefan Kühn (Max Planck Institute for Quantum Optics)

Presentation materials