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Electrical conductivity of hot QCD matter
W Cassing1, O Linnyk, T Steinert
1Institut für Theoretische Physik, Universität Giessen, 35392 Giessen, Germany.
Physical Review Letters
|May 21, 2013
Summary
Hot Quantum Chromodynamics (QCD) matter exhibits significant electric conductivity, surpassing that of copper and silver even near its critical temperature. This conductivity shows a distinct temperature dependence, dropping in the hadronic phase and stabilizing at higher temperatures.
Area of Science:
- Nuclear Physics and High-Energy Physics
- Quantum Chromodynamics (QCD) Matter Studies
Background:
- Understanding the properties of hot and dense nuclear matter is crucial for comprehending the early universe and heavy-ion collisions.
- Electric conductivity is a key transport property that probes the nature of matter under extreme conditions.
Purpose of the Study:
- To investigate the electric conductivity of hot Quantum Chromodynamics (QCD) matter across various temperatures.
- To analyze the temperature dependence of electric conductivity within the off-shell parton-hadron-string dynamics transport approach.
Main Methods:
- Utilized the off-shell parton-hadron-string dynamics transport approach.
- Simulated interacting partonic, hadronic, or mixed systems in a finite box with periodic boundary conditions.
- Calculated electric conductivity σ(0) by studying the system's response to an external electric field.
Main Results:
- Observed a significant temperature dependence in the ratio of electric conductivity to temperature (σ(0)/T).
- Found that the ratio drops in the hadronic phase, exhibits a minimum near the critical temperature (T(c)), and stabilizes above ~5T(c).
- Demonstrated that QCD matter near T(c) possesses higher electric conductivity than conventional conductors like copper or silver at room temperature.
Conclusions:
- The electric conductivity of hot QCD matter is strongly dependent on temperature.
- QCD matter near its critical temperature is an exceptionally good electric conductor.
- These findings provide insights into the transport properties of deconfined quarks and gluons.
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