Synopsis: Star chime could reveal small black holes

Smallish black holes left behind from the early universe might cause detectible vibrations as they pass through the sun or other stars.
Synopsis figure
M. Kesden and S. Hanasoge, Phys. Rev. Lett. (2011)

In theory, black holes come in all sizes, not just the star- and galaxy-scale objects that astronomers have already seen. In particular, smaller “primordial” black holes might have formed from density fluctuations in the first seconds after the big bang. In addition to providing a window into the universe in its earliest moments, these remnants could be the cold dark matter that makes up about a quarter of its present mass.

Previous observations rule out abundant black holes smaller than 10-16 or larger than 10-7 times the mass of the sun, but intermediate sizes could still account for cold dark matter. In Physical Review Letters, Michael Kesden at New York University and Shravan Hanasoge at Princeton University, New Jersey, propose that these medium-sized black holes could be detected when they pass through a star. Although the black hole will hardly be affected, it will leave lingering acoustic vibrations in the star, analogous to the ringing of a bell.

The hard part will be distinguishing this ringing from the ambient vibrations caused by turbulent fluid motion. But the researchers calculated that a black hole passing through a star like the sun excites modes with higher frequencies and larger spatial scales than turbulence does, making it easily noticeable. Unfortunately, the researchers also estimate that we would need millions of years to see such an event in our particular star. As an alternative, simultaneous but less detailed monitoring of many other stars could also reveal primordial black holes. – Don Monroe


Features

More Features »

Announcements

More Announcements »

Subject Areas

AstrophysicsCosmology

Previous Synopsis

Fluid Dynamics

Stop! Slippery water

Read More »

Next Synopsis

Superconductivity

Rare pressure

Read More »

Related Articles

Viewpoint: Dark Matter Still at Large
Cosmology

Viewpoint: Dark Matter Still at Large

No dark matter particles have been observed by two of the world’s most sensitive direct-detection experiments, casting doubt on a favored dark matter model. Read More »

Viewpoint: New Clues as to Why Boyajian’s Star is Dimming
Statistical Physics

Viewpoint: New Clues as to Why Boyajian’s Star is Dimming

A statistical analysis links a star’s mysterious brightness fluctuations to internal nonequilibrium phenomena, rather than structures orbiting around the star. Read More »

Viewpoint: Searching for Baby Planets in a Star’s Dusty Rings
Astrophysics

Viewpoint: Searching for Baby Planets in a Star’s Dusty Rings

Images of gaps in the dust and gas around a young star provide the best evidence to date that these gaps host newly formed planets. Read More »

More Articles