Analytical computation of quantum corrections to a nontopological soliton within the saddle-point approximation

Kovtun, Andrei (2022): Analytical computation of quantum corrections to a nontopological soliton within the saddle-point approximation. In: Physical Review D, Bd. 105, Nr. 3, 36011

Abstract

Nonrelativistic scalar field theory with an attractiveself-interaction possesses nontopological extended solutions with a finite energy in both finite and infinite-volume cases, namely, bright solitons. The analytical form of the solution itself is well known, though analytical studying of the quantum fluctuations in this background still requires more thorough investigation, for instance, analytical computation of quantum corrections to this background within the saddle-point approximation. In the present work this gap is filled. Both the 2-point Green's function and quantum corrections to the background are analytically computed and properly renormalized by means of the momentum cutoff procedure. It is deduced that quantum corrections are indeed small provided that the particle number is large. Also, we see that perturbation modes of the continuum spectrum at bright soliton background generate a gap in the energy spectrum. Moreover, it turns out that the whole spectrum is continuous modulo zero-modes, which is similar to Sine-Gordon solitons.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 2470-0010
• Sprache: Englisch