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Perfect Fluid Hydrodynamic Picture of Domain Wall Velocities at Strong Coupling
Romuald A Janik1, Matti Järvinen2,3, Hesam Soltanpanahi1
1Institute of Theoretical Physics, Jagiellonian University, Lojasiewicza 11, 30-348 Krakow, Poland.
Physical Review Letters
|September 2, 2022
Summary
We found a simple hydrodynamic formula to calculate the velocity of domain walls in strongly coupled theories undergoing first-order phase transitions. This formula, based on the equation of state, was validated using gauge/gravity duality.
Area of Science:
- High-energy physics
- Cosmology
- Condensed matter physics
Background:
- First-order phase transitions are crucial in early universe cosmology and condensed matter systems.
- Understanding the dynamics of these transitions, particularly bubble or domain wall velocity, is key to their physical implications.
- Strongly coupled theories present challenges for analytical calculations of phase transition dynamics.
Purpose of the Study:
- To derive a general formula for domain wall velocity in strongly coupled theories with first-order phase transitions.
- To relate this velocity to fundamental properties of the system, specifically its equation of state.
- To test the validity of the derived formula using a theoretical framework like gauge/gravity duality.
Main Methods:
- Application of perfect fluid hydrodynamics to model domain wall dynamics.
- Derivation of a formula for domain wall velocity based on the equation of state.
- Utilizing gauge/gravity duality to perform calculations and comparisons.
Main Results:
- A simple hydrodynamic formula for domain wall velocity was established for strongly coupled theories.
- The velocity was shown to be directly expressible in terms of the equation of state.
- Predictions for domain wall velocities were successfully tested against gauge/gravity duality calculations.
Conclusions:
- The derived hydrodynamic formula provides a powerful tool for analyzing first-order phase transitions in strongly coupled systems.
- The results highlight a universal behavior of domain wall velocities governed by the equation of state.
- Gauge/gravity duality serves as an effective method for validating theoretical predictions in strongly coupled regimes.
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