Vacuum Friction on a Rotating Pair of Atoms

Area of Science:

• Quantum Electrodynamics
• Atomic Physics
• Condensed Matter Physics

Background:

• The Casimir effect, arising from quantum vacuum fluctuations, explains London-van der Waals forces between atoms.
• Recent research explores the interaction between rotating matter and the quantum vacuum.

Purpose of the Study:

• To calculate the frictional torque experienced by a rotating pair of atoms due to zero-point radiation.
• To investigate the implications of this atomic-level friction on phenomena like dimer formation.

Main Methods:

• A semiclassical framework based on the fluctuation-dissipation theorem was employed.
• The full electrostatic coupling between induced dipoles in rotating atoms was considered.
• Calculations were performed for the zero-temperature case.

Main Results:

• A braking torque proportional to angular velocity and the cube of the fine-structure constant was identified.
• This torque, while weaker than London-van der Waals forces, is significant enough to promote dimer formation in atomic collisions.
• A novel friction phenomenon at the atomic scale was demonstrated.

Conclusions:

• Zero-point radiation induces a frictional torque on rotating atomic pairs.
• This friction mechanism can influence atomic interactions and dimer formation.
• The findings suggest a new paradigm for understanding irreversibility at the atomic level.