Black holes

Postdoctoral research Wenxuan Jia PhD '24 and his colleagues at the Laser Interferometer Gravitational-Wave Observatory (LIGO) have developed a way to reduce the impact of quantum noise by squeezing the laser light used in the detectors, enabling scientists to double the number of gravitational waves they can find, reports Karmela Padavic-Callaghan for New Scientist. “We realized that quantum noise will be limiting us a long time ago,” says Jia. “It’s not just a fancy [quantum] thing to demonstrate, it’s something that really affects the actual detector.” 

MIT physicists have found that “the presence of a tiny black hole speeding through the solar system could be identified by the gentle gravitational nudge it exerted on the Earth and other planets, which would alter their orbital paths by no more than a few feet,” reports Noah Haggerty for The Los Angeles Times. “It’s just fantastic that the most conceptually conservative response is to say, ‘It’s just super tiny black holes that were made a split second after the Big Bang,’” says Prof. David Kaiser. “It’s not inventing new forms of matter that have not yet been detected. It’s not changing the laws of gravity.”

A new study by MIT researchers suggests that miniscule black holes could briefly wobble the orbit of Mars and that these tiny black holes may pass through our solar system once every decade or so, reports Jess Thomson for Newsweek. “The researchers modeled the orbits of every large body in the solar system,” writes Thomson, “and found that tiny wobbles in the orbit of Mars could indicate one of the asteroid-mass black holes passing through.”

Science News reporter Emily Conover spotlights a new study by MIT researchers that proposes a new method to search for microscopic primordial black holes, which, if they exist, “could explain some or all of the universe’s dark matter.” The researchers suggest that when a primordial black hole passes close to a planet, it could “produce noticeable effects despite its tiny size.”
 

Prof. Christoph Kehle and his colleagues have demonstrated “that there is nothing in our known laws of physics to prevent the formation of an extremal black hole,” reports Steve Nadis for Quanta Magazine. The mathematical proof is “beautiful, technically innovative and physically surprising,” says Princeton University Professor Mihalis Dafermos. It hints at a potentially richer and more varied universe in which “extremal black holes could be out there astrophysically.”

PBS Space Time host Matt O’Dowd highlights research by Prof. David Kaiser and graduate student Elba Alonso-Monsalve delving into the composition of primordial black holes and potentially confirming the existence of color-charged black holes. “It may stand to reason, that colorful black holes were once the most natural thing in the world,” O’Dowd muses. 

Researchers at MIT have discovered the composition of primordial black holes, “potentially discovering an entirely new type of exotic black hole in the process,” reports Jacopo Prisco for CNN. “We were making use of Stephen Hawking’s famous calculations about black holes, especially his important result about the radiation that black holes emit,” says Prof. David Kaiser. “These exotic black holes emerge from trying to address the dark matter problem — they are a byproduct of explaining dark matter.”

Researchers at MIT have “analyzed how primordial black holes with a trait known as color charge could have formed in the soup of particles that composed the early universe,” reports Leah Crane for New Scientist. “They’re not really colors,” explains Prof. David Kaiser. “If we zoomed in with a microscope we wouldn’t see colors with our eyes, but it’s a way of accounting for the fact that nature seems to only allow color-neutral combinations.” 

Prof. Netta Engelhardt talks to New Scientist’s Thomas Lawton about the possibility of singularities existing outside black holes. Theorists can now probe singularities from a deeper perspective, using insights into the possible quantum foundations of gravity. This new approach “flips the script” on how we think about singularities, says Engelhardt.

MIT astronomers measured a black hole’s spin for the first time by tracking the X-ray flashes produced by a black hole following a tidal disruption event, reports Interesting Engineering’s Mrigakshi Dixit. “The spin value of a black hole tells us about how it evolved over the age of the universe,” explains Research Scientist Dheeraj Pasham. 

MIT astronomers have found a new way to measure how fast a black hole spins, observing the aftermath of a black hole tidal disruption event with a telescope aboard the International Space Station, reports Laura Baisas for Popular Science. “The only way you can do this is, as soon as a tidal disruption event goes off, you need to get a telescope to look at this object continuously, for a very long time, so you can probe all kinds of timescales, from minutes to months,” said Research Scientist Dheeraj Pasham.

Astronomers at MIT and elsewhere have determined how to measure the spin of a nearby supermassive black hole using a new calculation method, reports Isaac Schultz for Gizmodo. The team “managed to deduce a supermassive black hole’s spin by measuring the wobble of its accretion disk after a star has been disrupted—a polite word for torn up—by the gigantic object,” explains Schultz. “They found the black hole’s spin was less than 25% the speed of light—slow, at least for a black hole.” 

Researchers at MIT have discovered that a previously witnessed supermassive black hole has “a smaller companion black hole zipping around it, kicking up dust every time it goes by,” reports John Wenz for Astronomy. This discovery “shakes up our thinking of what the environment at the core of the galaxy looks like,” explains Wenz. “Instead of a simple disk of matter surrounding the central black hole, steadily swirling across its event horizon, the centers of galaxies could host multiple black holes of different sizes, leading to more complex feeding behavior.”

Astronomers from MIT and other institutions have found that periodic eruptions from a supermassive black hole located in a galaxy about 800 million light-years from Earth could be caused by a, “second, smaller black hole slamming into a disk of gas and dust, or ‘accretion disk,’ surrounding the supermassive black hole, causing it to repeatedly ‘hiccup’ out matter,” writes Rob Lea for Space.com. 

Senior Research Scientist Lisa Barsotti speaks with MIT Technology Review reporter Sophia Chen about how she and her colleagues developed a new device that uses quantum squeezing to help the LIGO detectors identify more celestial events, such as black hole mergers and neutron star collisions. “With these latest squeezing innovations, installed last year, the collaboration expects to detect gravitational waves up to 65% more frequently than before,” Chen explains.