Vacuum polarization in a one-dimensional effective   quantum-electrodynamics model
        - URL: http://arxiv.org/abs/2411.07246v2
 - Date: Mon, 10 Mar 2025 10:49:42 GMT
 - Title: Vacuum polarization in a one-dimensional effective   quantum-electrodynamics model
 - Authors: Timothée Audinet, Umberto Morellini, Antoine Levitt, Julien Toulouse, 
 - Abstract summary: We study a one-dimensional effective QED model of the hydrogen-like atom with delta-potential interactions.<n>This model resembles the three-dimensional effective QED theory with Coulomb interactions while being substantially simpler.
 - Score: 0.0
 - License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
 - Abstract:   With the aim of progressing toward a practical implementation of an effective quantum-electrodynamics (QED) theory of atoms and molecules, which includes the effects of vacuum polarization through the creation of virtual electron-positron pairs but without the explicit photon degrees of freedom, we study a one-dimensional effective QED model of the hydrogen-like atom with delta-potential interactions. This model resembles the three-dimensional effective QED theory with Coulomb interactions while being substantially simpler. We provide some mathematical details about the definition of this model, calculate the vacuum-polarization density, and the Lamb-type shift of the bound-state energy, correcting and extending results of previous works. We also study the approximation of the model in a finite plane-wave basis, and in particular we discuss the basis convergence of the bound-state energy and eigenfunction, of the vacuum-polarization density, and of the Lamb-type shift of the bound-state energy. We highlight the difficulty of converging the vacuum-polarization density in a finite basis and we propose a way to improve it. The present work could give hints on how to perform similar calculations for the three-dimensional effective QED theory of atoms and molecules. 
 
       
      
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