Description:

Astronomers reconstruct the life stories of cosmic phenomena by comparing vast populations frozen in a single moment, i.e. a human lifetime, or perhaps a PhD. Fast Radio Bursts (FRBs) are marked by their remarkable diversity—some repeat, others flash only once; some glow through persistent radio sources (PRS), some display exquisite polarization patterns—may not point to diverse origins, but rather to different evolutionary stages of a single underlying process.

I propose that FRBs are unified as a transient phase in the life cycle of compact objects. They begin with a cataclysm—a hypernova-like explosion that leaves behind a highly magnetized, rapidly spinning compact object. In the aftermath, as the surrounding plasma cloud expands and thins, coherent radio bursts begin to emerge as repeating FRBs. Over time, both the central engine and its environment evolve: magnetic fields decay, energy reservoirs dwindle, and the bursts grow fainter and rarer, eventually slipping below the detection threshold of surveys. In this evolutionary view, the familiar categories—“repeater,” “non-repeater,” “sporadic source,” or even “dormant FRB”—are merely snapshots along a continuum. They represent not fundamentally distinct kinds of objects, but different moments in the shared life of an extraordinary astrophysical phenomenon. With FAST and the Cosmic Antennae (being built), we are catching them in the acts.

 Di Li, Professor, Tsinghua University

Host: Wen-fai Fong