is dark matter made of black holes? NASA telescope may prove 50 year-old theory

new technology to explore a decades-old theory

last week on december 25th, 2021, NASA launched its james webb space telescope, marking the successor to the famous hubble telescope as the agency’s new flagship mission in astrophysics. the telescope will provide higher resolution and sensitivity over its predecessor, allowing scientists to observe some of the most distant events and objects in the universe, including the formation of the first galaxies (see designboom’s coverage of the JWST’s protective sunshield here).

along with its deployment, researchers have proposed that the james webb space telescope might allow for the exploration of one of stephen hawkings’ most controversial theories first proposed in the 1970s — that the invisible substance dark matter could be made of black holes which had formed in the first fraction of a second after the big bang.

image courtesy of arianespace, ESA, NASA, CSA, CNES

is dark matter made up of primordial black holes?

these so-called primordial black holes can range in size from tiny ones smaller than the head of a pin to supermassive ones spanning billions of miles. a new model of the universe, that these black holes make up the vast majority of black matter, has been proposed by astrophysicists at yale (see coverage here), the university of miami, and the european space agency (ESA).

the team awaits new data from NASA‘s recently launched james webb space telescope which may prove the theory to be true. this discovery would transform scientists’ understanding of the origins and nature of black holes — which have been observed — and dark matter — which has never been directly observed.

james webb space telescope, primary mirror segment | image © NASA/MSFC/david higginbotham

the new study, slight modified from hawkings’

this study, which has been accepted for publication in the astrophysical journal, harkens back to the early theory by physicists stephen hawking and bernard carr. the two had argued that in the earliest moments after the big bang, tiny fluctuations in the density of the universe may have created an undulating landscape with ‘lumpy’ regions that had extra mass — areas that would then collapse into black holes.

yale professor of astronomy and physics priyamvada natarajan explains the newer, slightly modified study, proposing that if most of the primordial black holes were ‘born’ at a size approximately 1.4 times the mass of earth’s sun, they may potentially account for all dark matter.

further, the JWST may prove or disprove the existence of primordial black holes in the near future, with the help of ESA’s laser interferometer space antenna (LISA) mission announced for the 2030s. if dark matter is made up of primordial black holes, more stars and galaxies would have formed around them in the early universe. precisely the epoch that the james webb telescope will be able to see. meanwhile, LISA will be able to pick up gravitational wave signals from early mergers of primordial black holes.