[Paper Review] Some notes on the phenomenological description of particle creation and its influence on the space-time metrics

V. A. Berezin|arXiv (Cornell University)|Apr 14, 2014

Relativity and Gravitational Theory3 citations

TL;DR

This paper proposes a phenomenological framework to describe particle creation by external fields, including gravitational fields, using effective field theory techniques. It derives a modified energy-momentum tensor that accounts for particle production, leading to a self-consistent modification of the space-time metric via semi-classical Einstein equations, thereby providing a covariant description of non-conservative processes in curved spacetime.

ABSTRACT

The method is proposed for the phenomenological description of particle creation by external fields (in the presence of gravitational field or without it)

Motivation & Objective

• To develop a phenomenological description of particle creation in the presence of external fields, including gravity.
• To address the lack of a consistent covariant framework for non-conservative particle production in quantum field theory in curved spacetime.
• To derive a modified energy-momentum tensor that incorporates particle creation effects.
• To study the back-reaction of particle production on the space-time geometry.
• To establish a semi-classical framework where particle creation influences the space-time metric through effective stress-energy terms.

Proposed method

• Formalism based on effective field theory to model particle creation as a source term in the energy-momentum tensor.
• Incorporation of particle production rates via a phenomenological source function in the semi-classical Einstein equations.
• Use of a covariant derivative condition to ensure consistency with general covariance in the presence of particle creation.
• Derivation of a modified stress-energy tensor that includes non-conservative contributions due to particle production.
• Solution of the semi-classical Einstein equations with the effective source to determine metric corrections.
• Application of the formalism to scenarios with external electromagnetic or gravitational fields, including de Sitter and FRW backgrounds.

Experimental results

Research questions

• RQ1 How can particle creation by external fields be consistently described in a covariant manner within a semi-classical gravity framework?
• RQ2 What is the effective energy-momentum tensor that accounts for particle production in curved spacetime?
• RQ3 How does particle creation influence the space-time metric through back-reaction effects?
• RQ4 What are the implications of non-conservative particle production for the dynamics of cosmological models?
• RQ5 Can a phenomenological model reproduce known results in particle creation (e.g., in de Sitter space) while preserving general covariance?

Key findings

• The paper derives a modified energy-momentum tensor that includes non-conservative contributions due to particle creation, preserving general covariance.
• The effective source term in the semi-classical Einstein equations correctly accounts for particle production rates in external fields.
• The formalism reproduces known results in de Sitter space, confirming consistency with established particle creation phenomena.
• Metric corrections due to particle creation are shown to be non-trivial and dependent on the particle production rate and background geometry.
• The framework allows for a consistent description of particle creation in both flat and curved spacetime, including gravitational and electromagnetic fields.
• The method provides a phenomenological bridge between quantum field theory in external fields and classical gravity, enabling study of back-reaction effects.