Spectral functions and critical dynamics of the O(4) model from classical-statistical lattice simulations
Abstract
We calculate spectral functions of the relativistic O (4) model from real-time lattice simulations in classical-statistical field theory. While in the low and high temperature phase of the model, the spectral functions of longitudinal (σ) and transverse (π) modes are well described by relativistic quasi-particle peaks, we find a highly non-trivial behavior of the spectral functions in the cross over region, where additional structures appear. Similarly, we observe a significant broadening of the quasi-particle peaks, when the amount explicit O (4) symmetry breaking is reduced. We further demonstrate that in the vicinity of the O (4) critical point, the spectral functions develop an infrared power law associated with the critical dynamics, and comment on the extraction of the dynamical critical exponent z from our simulations.
- Publication:
-
Nuclear Physics B
- Pub Date:
- January 2020
- DOI:
- 10.1016/j.nuclphysb.2019.114868
- arXiv:
- arXiv:1908.00912
- Bibcode:
- 2020NuPhB.95014868S
- Keywords:
-
- High Energy Physics - Lattice;
- Condensed Matter - Statistical Mechanics;
- High Energy Physics - Phenomenology;
- Nuclear Theory
- E-Print:
- Nucl. Phys. B 950, 114868 (2020)