Angularly excited and interacting boson stars and Q-balls

Abstract

We study angularly excited as well as interacting non-topological solitons, so-called Q-balls and their gravitating counterparts, so-called boson stars in 3+1 dimensions. Q-balls and boson stars carry a non-vanishing Noether charge and arise as solutions of complex scalar field models in a flat space-time background and coupled minimally to gravity, respectively. We present examples of interacting Q-balls that arise due to angular excitations, which are closely related to the spherical harmonics. We also construct explicit examples of rotating boson stars that interact with non-rotating boson stars. We observe that rotating boson stars tend to absorb the non-rotating ones for increasing, but reasonably small gravitational coupling. This is a new phenomenon as compared to the flat space-time limit and is related to the negative contribution of the rotation term to the energy density of the solutions. In addition, our results indicate that a system of a rotating and non-rotating boson star can become unstable if the direct interaction term in the potential is large enough. This instability is related to the appearance of ergoregions.

20 pages including 9 figures; for higher quality figures please contact the authors; v2: minor changes, final version to appear in Phys. Rev. D

References in corpus (7)

• Ergoregion instability of ultra-compact astrophysical objects
• Rotating Boson Stars and Q-Balls II: Negative Parity and Ergoregions
• Gravitational waves from fragmentation of a primordial scalar condensate into Q-balls
• Search for Neutral Q-balls in Super-Kamiokande II
• Supersymmetric Q-balls: A Numerical Study
• Entropy production by Q-ball decay for diluting long-lived charged particles
• Interacting Q-balls

Cited by in corpus (26)

• Dynamical Boson Stars
• Stable Phases of Boson Stars
• Rotating Boson Stars in 5 Dimensions
• Compact Boson Stars
• Geodesic motion in the space-time of a non-compact boson star
• Charged Q-balls and boson stars and dynamics of charged test particles
• Spinning Supersymmetric Q-balls
• Kerr black holes with synchronised scalar hair and boson stars in the Einstein-Friedberg-Lee-Sirlin model
• Regularized Kerr-Newman Solution as a Gravitating Soliton
• Compact (A)dS Boson Stars and Shells
• Glueball condensates as holographic duals of supersymmetric Q-balls and boson stars
• Q-balls in the $U(1)$ gauged Friedberg-Lee-Sirlin model
• Two-Scalar Bose-Einstein Condensates: From Stars to Galaxies
• Rotating multistate boson stars
• Spinning Q-balls in the complex signum-Gordon model
• Symmetry breaking in (gravitating) scalar field models describing interacting boson stars and Q-balls
• Excited oscillons: cascading levels and higher multipoles
• A Newtonian Analysis of Multi-scalar Boson Stars with Large Self-couplings
• Compact, charged boson-stars, -shells in the $\mathbb{C}{P}^N$ gravitating nonlinear sigma model
• Nodal compact $Q$-ball/$Q$-shell in the $\mathbb{C}{P}^N$ nonlinear sigma model
• Phase analyses for compact, charged boson stars and shells harboring black holes in the $\mathbb{C}{P}^N$ nonlinear sigma model
• The virial relation for compact Q-balls in the complex signum-Gordon model
• The virial relation for the Q-balls in the thermal logarithmic potential revisited analytically
• The further estimations of the Q-balls with one-loop motivated effective potential
• Non-topological Domain Walls in a Model with Broken Supersymmetry
• Understanding the Quantized Angular Momentum of Rotating Q-balls