• Corpus ID: 252567989

Gravitational waves and primordial black holes from chirality imbalanced QCD first-order phase transition with $\mathcal {P}$ and $\mathcal {CP}$ violation

@inproceedings{Shao2022GravitationalWA,
  title={Gravitational waves and primordial black holes from chirality imbalanced QCD first-order phase transition with \$\mathcal \{P\}\$ and \$\mathcal \{CP\}\$ violation},
  author={Jing Shao and Mei Huang},
  year={2022}
}

• Jing Shao, Mei Huang
• Published 28 September 2022
• Physics

The chirality imbalance in QCD is spontaneously induced by a repulsive axial-vector interaction from the instanton anti-instanton pairing at high temperature above the chiral phase transition, and vanishes at low temperature. Phase transition of the chirality imbalance is always a first-order one in the early universe with P and CP violation. The spectra of gravitational waves and the formation of the primordial black holes from this first-order phase transition is investigated in this work, and the effect of a strong magnetic field is also analyzed. The gravitational waves produced by chirality imbalance can be detected by LISA, Taiji and DECIGO, with the peak energy density locating in the range of 10 − 11 to 10 − 9 and the peak frequencies lying in the range of 10 − 5 Hz to 10 − 2 Hz. The spectrum with larger axial vector coupling strength and stronger magnetic field has higher peak energy density and lower peak frequency. According to this trend, the gravitational waves spectra might also be able to be detected by SKA, IPTA and EPTA. Based on the mechanism of postponement of the false vacuum decay, it is scarcely possible to form PBHs in our model with typical parameters because the phase transition completes in an extreme short time and thus the false vacuum energy density decays sharply.