Classical physics and quantum loops.

Area of Science:

• Quantum Field Theory
• Classical Physics
• Particle Physics

Background:

• The loop expansion in quantum field theory typically associates quantum effects with loops and classical effects with tree diagrams.
• This standard interpretation suggests a clear separation between quantum mechanical phenomena and classical physics.

Purpose of the Study:

• To investigate counterexamples where classical effects originate from loop diagrams.
• To elucidate the connection between these classical terms and the long-range influences of massless particles.

Main Methods:

• Analysis of loop expansion in quantum field theory.
• Identification and examination of specific counterexamples.
• Mathematical derivation of relationships between classical terms and massless particle effects.

Main Results:

• Demonstration that loop diagrams can yield classical effects, contrary to standard assumptions.
• Identification of the specific mechanisms through which classical phenomena arise from quantum loops.
• Quantification of the relationship between classical terms in loop diagrams and the long-range effects of massless particles.

Conclusions:

• The distinction between classical and quantum effects in loop expansion is not absolute.
• Classical effects can be intrinsically linked to quantum processes, particularly involving massless particles.
• Further research into these mixed classical-quantum phenomena is warranted for a complete understanding of quantum field theory.