RIVERSIDE, Calif. -- Supermassive black holes — with masses ranging from millions to billions of times that of our sun — sit at the centers of most large galaxies. Astronomers have observed such black holes to exist as early as 450 million years after the Big Bang, a finding that challenges our understanding of cosmic evolution.
How did these enormous objects form so quickly? This question remains one of the most pressing mysteries in astrophysics.
To help answer it, Hai-Bo Yu, a theoretical physicist at the University of California, Riverside, has received a $260,000 grant from the John Templeton Foundation. His research will investigate how supermassive black holes, or SMBHs, were “seeded” in the early universe.
Seeding refers to the formation of an initial small black hole that grows — either by accreting matter or merging with others — into a supermassive one. The presence of SMBHs at high redshifts implies either an unusually massive initial seed or extremely rapid growth.
“We will investigate a new mechanism for seeding supermassive black holes in the early universe,” Yu said. “The origin of SMBHs and the nature of dark matter are two of the biggest unsolved problems in science. Our goal is to tackle both within a unified theoretical framework.”
Yu’s team proposes that self-interacting dark matter (SIDM) halos — unlike the collisionless dark matter in standard cosmology — can undergo gravitational collapse, forming seed black holes. These seeds could then grow rapidly enough to explain the SMBHs already seen by the James Webb Space Telescope, or JWST, at cosmic dawn.
SIDM models posit that dark matter particles interact via a dark force, allowing them to scatter and conduct heat in the central regions of a dark matter halo, a key condition for halo collapse. Such behavior could offer a natural pathway for early black hole formation.
The three-year project will merge analytical modeling with detailed cosmological simulations to study SMBH evolution in the SIDM framework. Yu’s team will compare its predictions to JWST observations and search for related astrophysical signals in the later universe.
“We expect our work will provide crucial insights into the role of dark matter interactions in shaping both the early and present-day universe,” Yu said.
The John Templeton Foundation, known for supporting research on topics ranging from cosmology to human purpose and ethics, previously funded Yu’s work on SIDM.
“We are deeply grateful for the foundation’s continued and generous support of our research,” Yu said.
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