[理论室学术报告] How to talk to a mirror world?-- A new theory for solving the puzzles of dark matter, neutron lifetime, and star evolution
A mirror sector of our universe has been conjectured since Lee and Yang published their seminar work on parity violation. There are many desirable features from such mirror matter that has been predicted. However, no concrete model was successful or compatible with our known universe. A new mirror-matter model is proposed under a spontaneously broken mirror symmetry, which results in oscillations of neutral particles. As it turns out, neutron-mirror neutron (n-n') oscillations become the best messenger between the ordinary and the mirror worlds. The new n-n' model resolves the neutron lifetime discrepancy, i.e., the 1% difference between measurements from "Beam" and "Bottle" experiments. 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. A new theory of evolution and nucleosynthesis in stars based on the new model of n-n' oscillations presents remarkable agreement between the predictions and the observations. For example, progenitor mass limits and structures for white dwarfs and neutron stars, two different types of core collapse supernovae (Type II-P and Type II-L), pulsating phenomena in stars, etc, can all be easily and naturally explained under the new theory. Further tests and applications of the new theory will be discussed as well.
Wanpeng Tan，B.S. from Beijing University, 1994; M.S. from Institute of Theoretical Physics, Chinese Academy of Sciences; Ph.D. from Michigan State University. Currently research associate professor at Institute for Structure and Nuclear Astrophysics (ISNAP), Joint Institute for Nuclear Astrophysics - Center for the Evolution of the Elements (JINA-CEE), and Department of Physics, University of Notre Dame.