Séminaires généraux

Neutron lifetime anomaly and consistent origin of dark matter and baryon asymmetry

by Wanpeng Tan (University of Notre Dame)

Salle de réunion Bât.108 (IJCLab)

Salle de réunion Bât.108



Originated from Lee and Yang's seminal work on parity violation, a rather exact mirror matter model is proposed using spontaneous mirror symmetry breaking, which results in oscillations of neutral particles [1-5]. As it turns out, neutron-mirror neutron (n-n') oscillations become one of the best messengers between the ordinary and the mirror worlds. The new n-n' model resolves the neutron lifetime anomaly, i.e., the 1% difference between measurements from "Beam" and "Bottle" experiments [1]. The picture of how the mirror-to-ordinary matter density ratio is evolved in the early universe into today's observed dark-to-baryon matter density ratio (~5.4) is gracefully demonstrated [1].

More intriguingly, a natural extension of the new model applying kaon oscillations in the early universe shows a promising solution to the long-standing baryon asymmetry problem with new insights for the QCD phase transition and B-violation topological processes [3]. A consistent picture for the origin of both baryon asymmetry and dark matter can then be depicted with kaon and neutron oscillations under the new model. Based on this model, a new theory - extended Standard Model with Mirror Matter (SM^3) [6] is developed for an elegant solution to dark energy and a foundation for addressing consistently and quantitatively many other celebrated puzzles: evolution of stars [2], ultrahigh energy cosmic rays [4], unitarity of the CKM matrix [5], etc. Last but not least, various laboratory measurements using current technology are proposed to test the new theory [5].

[1] https://arxiv.org/abs/1902.01837 [Phys. Lett. B 797, 134921 (2019)]

[2] https://arxiv.org/abs/1902.03685

[3] https://arxiv.org/abs/1904.03835 [Phys. Rev. D 100, 063537 (2019)]

[4] https://arxiv.org/abs/1903.07474

[5] https://arxiv.org/abs/1906.10262

[6] https://arxiv.org/abs/1908.11838